RU2792670C2 - Communication system, communication terminal device and communication node - Google Patents

Abstract

FIELD: radio communications.

SUBSTANCE: communication system comprises a user device and base stations, respectively, configured to perform wireless communication with the user device, wherein the base stations include a main base station and a secondary base station that configure dual connectivity for the user device, while the secondary base station is configured with a permission setting related to a transmission to the secondary base station in the uplink without a permission.

EFFECT: technical result is communication with low latency.

20 cl, 68 dwg

Description

Technical field

[0001] The present invention relates to a communication system, etc., in which radio communication is performed between a communication terminal device such as a user equipment device and a base station device.

State of the art

[0002] The 3rd generation partnership project, a standardization organization for a mobile communication system, develops communication systems, which are referred to as long-term evolution (LTE), regarding radio sections, and system architecture evolution (SAE), regarding the overall system configuration, including including a core network and a radio access network, which are also collectively referred to as a network hereinafter (eg, see Non-Patent Documents 1 to 5). This communication system is also referred to as the 3.9 generation (3.9G) system.

[0003] In LTE, as an access scheme, orthogonal frequency division multiplexing (OFDM) is used in the downlink direction and single carrier frequency division multiple access (SC-FDMA) is used in the uplink direction. In addition, unlike wideband code division multiple access (W-CDMA), LTE does not provide circuit switching, but only provides a packet communication system.

[0004] The decisions made in 3GPP regarding the frame configuration in the LTE system described in Non-Patent Document 1 (Chapter 5) are described with reference to FIG. 1. FIG. 1 is a diagram illustrating the configuration of a radio frame used in an LTE communication system. When referring to FIG. 1, one radio frame is 10ms. The radio frame is divided into ten subframes of the same size. The subframe is divided into two slots of the same size. The first and sixth subframes contain the downlink synchronization signal per radio frame. Synchronization signals are classified into Primary Synchronization Signal (P-SS) and Secondary Synchronization Signal (S-SS).

[0005] Non-Patent Document 1 (Chapter 5) describes 3GPP decisions regarding channel configuration in an LTE system. It is assumed that the Closed Subscriber Group (CSG) cell uses exactly the same channel configuration as the non-CSG cell.

[0006] A Physical Broadcast Channel (PBCH) is a channel for downlink transmission from a base station device (hereinafter, may simply be referred to as "base station") to a communication terminal device (hereinafter, may simply be referred to as "communication terminal"), such as user equipment (hereinafter may simply be referred to as "user equipment"). The BCH transport block is displayed in four subframes within a 40ms interval. There is no explicit signaling indicating a 40ms time reference.

[0007] The Control Format Indicator Physical Channel (PCFICH) is a channel for downlink transmission from a base station to a communication terminal. The PCFICH notifies the number of Orthogonal Frequency Division Multiplexing (OFDM) symbols that are used for the PDCCH from the base station to the communication terminal. PCFICH is transmitted per subframe.

[0008] A Physical Downlink Control Channel (PDCCH) is a channel for downlink transmission from a base station to a communication terminal. The PDCCH notifies resource allocation information for the Downlink Shared Channel (DL-SCH), which is one of the transport channels described below, of resource allocation information for the Paging Channel (PCH), which is one of the transport channels, described below, and hybrid automatic repeat request (HARQ) information that is related to the DL-SCH. The PDCCH carries an uplink scheduling grant. The PDCCH carries a positive acknowledgment (Ack)/negative acknowledgment (Nack) which is an uplink transmission response signal. The PDCCH is also referred to as the L1/L2 control signal.

[0009] A Physical Downlink Shared Channel (PDSCH) is a channel for downlink transmission from a base station to a communication terminal. The Downlink Shared Channel (DL-SCH), which is a transport channel, and the PCH, which is a transport channel, are mapped to the PDSCH.

[0010] A Physical Multicast Channel (PMCH) is a channel for downlink transmission from a base station to a communication terminal. A Multicast Channel (MCH), which is a transport channel, is mapped to the PMCH.

[0011] The Physical Uplink Control Channel (PUCCH) is a channel for uplink transmission from a communication terminal to a base station. PUCCH carries Ack/Nack, which is a downlink transmission response signal. The PUCCH carries a Channel Quality Indicator (CQI) report. CQI is quality information indicating the quality of received data or channel quality. In addition, the PUCCH carries a scheduling request (SR).

[0012] A Physical Uplink Shared Channel (PUSCH) is a channel for uplink transmission from a communication terminal to a base station. An uplink shared channel (UL-SCH), which is one of the transport channels, is mapped to the PUSCH.

[0013] The Hybrid ARQ Indicator Physical Channel (PHICH) is a channel for downlink transmission from a base station to a communication terminal. The PHICH carries an Ack/Nack, which is an uplink transmission response signal. The Physical Random Access Channel (PRACH) is a channel for uplink transmission from a communication terminal to a base station. PRACH carries the random access preamble.

[0014] The downlink reference signal (RS) is a known symbol in the LTE communication system. The following five types of downlink reference signals are defined as: cell-specific reference signal (CRS), MBSFN reference signal, data demodulation reference signal (DM-RS), which is a UE-specific reference signal, positioning reference signal (PRS), and channel status information signal (CSI-RS). Physical layer measurement objects at the communication terminal include received reference signal powers (RSRP).

[0015] The transport channels described in Non-Patent Document 1 (Chapter 5) are described. Broadcast channel (BCH), among the downlink transport channels, is broadcast over the entire base station (cell) coverage. The BCH is mapped to the Physical Broadcast Channel (PBCH).

[0016] Hybrid ARQ (HARQ) retransmission control is applied to a downlink shared channel (DL-SCH). Broadcast DL-SCH can be carried out over the entire coverage of the base station (cell). DL-SCH supports dynamic or semi-static resource allocation. Semi-static resource allocation is also referred to as persistent scheduling. The DL-SCH supports Discontinuous Reception (DRX) for a communication terminal to provide power savings to the communication terminal. The DL-SCH is mapped to the Physical Downlink Shared Channel (PDSCH).

[0017] The Paging Channel (PCH) supports DRX for the communication terminal to provide energy savings to the communication terminal. It is required to broadcast the PCH over the entire coverage of the base station (cell). The PCH is mapped to physical resources such as a physical downlink shared channel (PDSCH) that can be used dynamically for traffic.

[0018] A multicast channel (MCH) is used to broadcast over the entire coverage of a base station (cell). The MCH supports Multimedia Broadcast/Multicast Service (MBMS) SFN services (MTCH and MCCH) combining in multi-cell transmission. The MCH supports semi-static resource allocation. MCH is mapped to PMCH.

[0019] Hybrid ARQ (HARQ) retransmission control is applied to an uplink shared channel (UL-SCH) among uplink transport channels. UL-SCH supports dynamic or semi-static resource allocation. The UL-SCH is mapped on the Physical Uplink Shared Channel (PUSCH).

[0020] The random access channel (RACH) is limited to control information. RACH is associated with the threat of conflict. The RACH is mapped to the Physical Random Access Channel (PRACH).

[0021] HARQ is described. HARQ is a technique for improving the communication quality of a channel by combining automatic retransmission request (ARQ) and error correction (forward error correction). The advantage of HARQ is that error correction functions efficiently by retransmission even for a channel whose link quality varies. In particular, it is also possible to further achieve quality improvement in retransmission by combining the reception results of the first transmission and the reception results of the retransmission.

[0022] An example of a retransmission method is described. If the receiver cannot successfully decode the received data, in other words, if a cyclic redundancy check (CRC) error occurs (CRC=NG), then the receiver sends a "Nack" to the transmitter. The transmitter that received the "Nack" retransmits the data. If the receiver successfully decodes the received data, in other words, if no CRC error occurs (CRC=OK), the receiver sends an "Ack" to the transmitter. The transmitter that received "Ack" transmits the following data.

[0023] The logical channels described in Non-Patent Document 1 (Chapter 6) are described. The Broadcast Control Channel (BCCH) is a downlink channel for broadcasting system control information. The BCCH, which is a logical channel, is mapped to a broadcast channel (BCH) or a downlink shared channel (DL-SCH), which is a transport channel.

[0024] The Paging Control Channel (PCCH) is a downlink channel for transmitting paging information and system information change notifications. The PCCH is used when the network does not know the cell location of the communication terminal. The PCCH, which is a logical channel, is mapped to a paging channel (PCH), which is a transport channel.

[0025] The Common Control Channel (CCCH) is a channel for transmitting control information between communication terminals and a base station. CCCH is used when the communication terminals do not have an RRC connection to the network. In the downlink direction, the CCCH is mapped on a downlink shared channel (DL-SCH), which is a transport channel. In the uplink direction, the CCCH is mapped on an uplink shared channel (UL-SCH), which is a transport channel.

[0026] The Multicast Control Channel (MCCH) is a downlink channel for point-to-multipoint transmission. The MCCH is used to transmit MBMS control information for one or more MTCHs from a network to a communication terminal. The MCCH is only used by the communication terminal during MBMS reception. The MCCH is mapped to a Multicast Channel (MCH), which is a transport channel.

[0027] A dedicated control channel (DCCH) is a channel that transmits dedicated control information between a communication terminal and a network on a point-to-point basis. DCCH is used when the communication terminal has an RRC connection. The DCCH is mapped on the uplink shared channel (UL-SCH) on the uplink and mapped on the downlink shared channel (DL-SCH) on the downlink.

[0028] A dedicated traffic channel (DTCH) is a point-to-point communication channel for transmitting user information to a dedicated communication terminal. DTCH exists on the uplink as well as the downlink. The DTCH is mapped on the uplink shared channel (UL-SCH) on the uplink and mapped on the downlink shared channel (DL-SCH) on the downlink.

[0029] A Multicast Traffic Channel (MTCH) is a downlink channel for transmitting traffic data from a network to a communication terminal. MTCH is a channel that is used by the communication terminal only during MBMS reception. MTCH is mapped to a multicast channel (MCH).

[0030] CGI is a global cell identifier. ECGI is the E-UTRAN Global Cell Identifier. In LTE, a Closed Subscriber Group (CSG) cell has been introduced, and Advanced Long Term Evolution (LTE-A) and Universal Mobile Telecommunications System (UMTS) are described below.

[0031] A Closed Subscriber Group (CSG) cell is a cell in which subscribers who are allowed to use are specified by the operator (hereinafter referred to as a "cell for specific subscribers"). These subscribers are allowed to access one or more cells of the public land mobile communications network (PLMN). One or more cells that the specified subscribers are allowed to access is referred to as "CSG cell(s)." Note that access is limited in PLMN.

[0032] A CSG cell is a part of a PLMN that broadcasts specific CSG identification data (CSG ID) and broadcasts TRUE in the CSG indication. Authorized subscriber group members who have registered in advance access the CSG cells using the CSG ID, which is access authorization information.

[0033] Broadcast transmission of the CSG ID is carried out by the cell or cells of the CSG. In the LTE communication system, there are many CSG IDs. CSG IDs are used by communication terminals (UEs) to make it easier for CSG-associated members to access.

[0034] The locations of communication terminals are tracked based on an area composed of one or more cells. The locations are tracked to ensure tracking of the locations of the communication terminals and the call of the communication terminals, in other words, the incoming call of the communication terminals even in the idle state. An area for tracking the locations of communication terminals is referred to as a tracking area.

[0035] In 3GPP, base stations are being developed, which are referred to as Home-Node-B (Home-NB; HNB) and Home-e-Node-B (Home-eNB; HeNB). HNB/HeNB is a base station for, for example, home, corporate or commercial service access in UTRAN/E-UTRAN. Non-Patent Document 2 discloses three different modes of access to HeNB and HNB. In particular, an open access mode, a closed access mode, and a hybrid access mode are disclosed.

[0036] In addition, Long Term Evolution Enhanced (LTE-A) specifications are considered 3GPP Revision 10 (see Non-Patent Documents 3 and 4). LTE-A is based on the LTE radio communication system and is capable of adding several new techniques to the system.

[0037] With respect to the LTE-A system, carrier aggregation (CA) has been developed in which two or more component carriers (CCs) are aggregated to support wider bandwidths up to 10MHz. Non-Patent Document 1 describes CA.

[0038] In the case where the CA is configured, the UE has one RRC connection to the network (NW). In an RRC connection, one serving cell provides NAS mobility information and security input. This cell is referred to as a primary cell (PCell). In the downlink, the carrier corresponding to the PCell is the downlink primary component carrier (DL PCC). In the uplink, the carrier corresponding to the PCell is the uplink primary component carrier (UL PCC).

[0039] Secondary cell (SCell) is configured to form a group of serving cells with PCell, in accordance with the capabilities of the UE. In the downlink, the carrier corresponding to the SCell is a secondary downlink component carrier (DL SCC). In the uplink, the carrier corresponding to the SCell is an uplink secondary component carrier (UL SCC).

[0040] A serving cell group of one PCell and one or more SCells is configured for one UE.

[0041] New techniques in LTE-A include a wider bandwidth support technique (wider bandwidth expansion) and a Coordinated Multipoint Transmission and Reception (CoMP) technique. CoMP, which is developed for LTE-A in 3GPP, is described in Non-Patent Document 1.

[0042] In addition, the use of small eNBs (hereinafter also referred to as "small scale base station devices") configuring small cells is being developed in 3GPP to meet huge traffic in the future. In an exemplary development methodology, a large number of small eNBs are installed to configure a large number of small cells that increase spectral efficiency and communication capacity. Specific techniques include dual connectivity (abbreviated as DC) by which a UE communicates with two eNBs through a connection to them. Non-Patent Document 1 describes DC.

[0043] With reference to eNBs that implement dual connectivity (DC), one may be referred to as a master eNB (abbreviated as MeNB) and the other may be referred to as a secondary eNB (abbreviated as SeNB).

[0044] The traffic flow of the mobile network is increasing, and the communication speed is also increasing. It is expected that communication speeds will further increase when LTE and LTE-A are fully operational.

[0045] In order to obtain more advanced mobile communication, a fifth generation radio access system (hereinafter also referred to as "5G") is being developed, the service launch of which is scheduled for 2020 and beyond. For example, in Europe, an organization called METIS summarizes the requirements for 5G (see Non-Patent Document 5).

[0046] The 5G radio access system requirements show that the system capacity must be 1000 times higher, the data rate must be 100 times higher, the data latency must be lower by a ratio of one in ten (1/10) and the number of simultaneously connected there should be 100 times more communication terminals than those in the LTE system in order to further reduce power consumption and cost of the device.

[0047] To meet such requirements, 5G standards as Revision 15 are being studied in 3GPP (see Non-Patent Documents 6 to 10). Techniques regarding 5G radio communication sections are referred to as "New Radio Access Technology" ("New Radio Communication" abbreviated as NR), and several new techniques are being developed (see Non-Patent Documents 11, 15 and 16). Examples of such developments include DC using LTE and NR, and sharing of frequency resources between LTE and NR (see Non-Patent Documents 12 and 13).

Prior Art Documents

Non-Patent Documents

[0048] Non-Patent Document 1: 3GPP TS36.300 V14.3.0

Non-Patent Document 2: 3GPP S1-083461

Non-Patent Document 3: 3GPP TR 36.814 V9.2.0

Non-Patent Document 4: 3GPP TR 36.912 V14.0.0

Non-Patent Document 5: "Scenarios, requirements and KPIs for 5G mobile and wireless system", ICT-317669-METIS/D1.1

Non-Patent Document 6: 3GPP TR 23.799 V14.0.0

Non-Patent Document 7: 3GPP TR 38.801 V14.0.0

Non-Patent Document 8: 3GPP TR 38.802 V14.1.0

Non-Patent Document 9: 3GPP TR 38.804 V14.0.0

Non-Patent Document 10: 3GPP TR 38.912 V14.0.0

Non-Patent Document 11: 3GPP RP-172115

Non-Patent Document 12: 3GPP TS37.340 V1.0.2

Non-Patent Document 13: 3GPP R1-1701527

Non-Patent Document 14: 3GPP R1-1712747

Non-Patent Document 15: 3GPP TS 38.211 V1.0.0

Non-Patent Document 16: 3GPP TS 38.300 V1.1.1

Non-Patent Document 17: 3GPP TS 36.304 V14.4.0

Non-Patent Document 18: 3GPP TS 36.331 V14.4.0

Essence of the Invention

Problems to be solved by the invention

[0049] NR discussed DC using eNB and gNB. NR requires communication with low latency and high reliability. Since the transmission destination of the uplink transmission data from the UE is determined according to the capacity of the uplink data buffer when configuring the DC, the UE cannot always transmit the uplink data to the low latency base station during communication requiring low latency. . Thus, the waiting time for uplink data transmission increases.

[0050] A control technology for sharing the same frequencies between LTE and NR has been discussed. The UE communicates with the eNB and/or gNB by switching transmitters and/or receivers between NR and LTE. Because timings in LTE and NR overlap with respect to sharing between LTE and NR, the UE has problems in that it is unable to receive synchronization from the eNB and/or gNB and communicate in LTE and NR.

[0051] In view of the problems, one of the objects of the present invention is to provide a communication system, etc. with low latency and high reliability at NR.

Problem Solver

[0052] The present invention provides, for example, a communication system including: a communication terminal device; and a plurality of nodes configured to connect with the communication terminal device for radio communication and provide a split radio channel (bearer) for the communication terminal device, wherein the communication terminal device is configured to perform an uplink transmission to the uplink transmission node among the plurality of nodes, and an uplink transmission node is determined by an uplink transmission node determination process in which a node that provides uplink transmission from a communication terminal device with a lower latency among the plurality of nodes is determined as an uplink transmission node.

[0053] The present invention provides, for example, a communication terminal apparatus configured to perform radio communication with a plurality of nodes that provide a split radio channel, wherein the communication terminal apparatus is configured to perform an uplink transmission to an uplink transmission node selected by a process determining an uplink transmission node, and an uplink transmission node determination process is a process for determining, as an uplink transmission node, a node that provides an uplink transmission from a communication terminal device with a lower latency among the plurality of nodes.

[0054] The present invention provides, for example, a communication node configured to provide a split radio channel to a communication terminal device together with another communication node, wherein the communication node is configured to operate as an uplink transmission node to be used by the terminal device for uplink transmission, having been selected by an uplink transmission node determination process, and the uplink transmission node determination process is a process for determining, as an uplink transmission node, a node that provides uplink transmission from the terminal device links with lower latency among multiple nodes.

Results of the Invention

[0055] The present invention may provide a communication system, etc. with low latency and high reliability at NR.

[0056] The objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when considered in conjunction with the accompanying drawings.

Brief Description of Drawings

[0057] FIG. 1 is a diagram illustrating a radio frame configuration for use in an LTE communication system.

Fig. 2 is a block diagram showing the general configuration of an LTE communication system 200 discussed by 3GPP.

Fig. 3 is a block diagram showing the configuration of the user equipment 202 shown in FIG. 2, which is a communication terminal according to the present invention.

Fig. 4 is a block diagram showing the configuration of the base station 203 shown in FIG. 2, which is the base station according to the present invention.

Fig. 5 is a block diagram showing the configuration of an MME according to the present invention.

Fig. 6 is a flowchart showing a summary of the operation that is performed by a communication terminal (UE) in the LTE communication system from cell search to idle state.

Fig. 7 shows the concept of a cell configuration when macro eNBs and small eNBs coexist.

Fig. 8 illustrates an exemplary sequence for the MN to configure for the UE which node the uplink transmission is addressed to, according to the first embodiment.

Fig. 9 illustrates an exemplary sequence for a UE to determine an uplink transmission node, in accordance with the first embodiment.

Fig. 10 illustrates an exemplary sequence for a UE to determine an uplink transmission node using a threshold, according to the first embodiment.

Fig. 11 illustrates an exemplary sequence for a UE to determine an uplink transmission node using a threshold, according to the first embodiment.

Fig. 12 illustrates an exemplary sequence for an SN to perform unauthorized transmission with a split radio channel, according to the first modification of the first embodiment.

Fig. 13 illustrates an exemplary sequence for an SN to perform unauthorized transmission with a split radio channel, according to the first modification of the first embodiment.

Fig. 14 illustrates another exemplary sequence for an SN to perform unauthorized transmission with a split radio channel, according to the first modification of the first embodiment.

Fig. 15 illustrates another exemplary sequence for an SN to perform unauthorized transmission with a split radio channel, according to the first modification of the first embodiment.

Fig. 16 illustrates another exemplary sequence for an SN to perform unauthorized transmission with a split radio channel, according to the first modification of the first embodiment.

Fig. 17 illustrates another exemplary sequence for an SN to perform unauthorized transmission with a split radio channel, according to the first modification of the first embodiment.

Fig. 18 illustrates an exemplary sequence for MNs and SNs to perform unauthorized transmission with a split radio channel, according to the first modification of the first embodiment.

Fig. 19 illustrates an exemplary sequence for MNs and SNs to perform unauthorized transmission with a split radio channel, according to the first modification of the first embodiment.

Fig. 20 illustrates another exemplary sequence for an SN to perform unauthorized transmission with a split radio channel, according to the first modification of the first embodiment.

Fig. 21 illustrates another exemplary sequence for an SN to perform unauthorized transmission with a split radio channel, according to the first modification of the first embodiment.

Fig. 22 illustrates another exemplary sequence for an SN to perform unauthorized transmission with a split radio channel, according to the first modification of the first embodiment.

Fig. 23 illustrates another exemplary sequence for an SN to perform unauthorized transmission with a split radio channel, according to the first modification of the first embodiment.

Fig. 24 illustrates an exemplary sequence for configuring the transmission without permission when duplicating packets, in accordance with the second embodiment.

Fig. 25 illustrates an exemplary sequence for configuring the transmission without permission when duplicating packets, in accordance with the second embodiment.

Fig. 26 illustrates an exemplary sequence for configuring the transmission without permission when duplicating packets, in accordance with the second embodiment.

Fig. 27 illustrates an exemplary sequence for configuring duplication of packets in an uplink communication in which an unauthorized transmission has been configured according to the second embodiment.

Fig. 28 illustrates an exemplary sequence for configuring duplication of packets in an uplink communication in which non-granted transmission has been configured according to the second embodiment.

Fig. 29 illustrates an exemplary sequence for configuring duplication of packets in an uplink communication in which non-granted transmission has been configured according to the second embodiment.

Fig. 30 illustrates an exemplary sequence for notifying the activation of duplication of packets and the activation of a configuration for permissive transmission through the same signaling, and performing duplication of packets and configuration of permissive transmission, according to the second embodiment.

Fig. 31 illustrates an exemplary sequence for notifying the activation of duplication of packets and the activation of a configuration for permissive transmission through the same signaling, and performing duplication of packets and configuration of permissive transmission, according to the second embodiment.

Fig. 32 illustrates an example in which the uplink preemption indication is performed with an area in frequency resources other than that to be used for transmitting and receiving downlink user data according to the third embodiment.

Fig. 33 illustrates an example in which the uplink preemption indication is performed by the PDCCH, according to the third embodiment.

Fig. 34 illustrates an example in which a predetermined code is used as information indicating the occurrence of preemption according to the first modification of the third embodiment.

Fig. 35 illustrates an example of reordering of SS blocks in an SS burst in NR, according to the fourth embodiment.

Fig. 36 is a timing diagram illustrating the transmission of SS blocks in NR that do not overlap with non-MBSFN signals in LTE, according to the fourth embodiment.

Fig. 37 illustrates an example in which an offset is provided at a frame boundary between LTE and NR, according to the fourth embodiment.

Fig. 38 illustrates an example of changing the spacing of the SS pulse burst to NR, according to the fourth embodiment.

Fig. 39 is a sequence diagram illustrating a procedure when a main base station issues a single TX/double TX instruction to the UE, according to the fifth embodiment.

Fig. 40 is a sequence diagram illustrating information notification regarding the SCell when the SCell is activated/deactivated according to the fifth embodiment.

Fig. 41 illustrates an exemplary PUCCH transmission in LTE and NR in the same subframe with one TX, according to the first modification of the fifth embodiment.

Fig. 42 is a sequence diagram for the UE to determine the path loss in SUL with the downlink measurement signal from the base station NR, according to the sixth embodiment.

Fig. 43 illustrates an example of FL-DMRS preemption for an eMBB UE, according to the seventh embodiment.

Fig. 44 illustrates an example of FL-DMRS preemption for an eMBB UE, according to the seventh embodiment.

Fig. 45 illustrates an example of FL-DMRS preemption when FL-DMRS and add-DMRS are configured for the eMBB UE, according to the seventh embodiment.

Fig. 46 illustrates an example of FL-DMRS preemption when only FL-DMRS is configured in one slot for the eMBB UE, according to the seventh embodiment.

Fig. 47 illustrates an exemplary process flow for preempting FL-DMRS when only FL-DMRS is configured in a slot for an eMBB UE, according to the seventh embodiment.

Fig. 48 illustrates an exemplary process flow for preempting FL-DMRS when only FL-DMRS is configured in a slot for an eMBB UE, according to the seventh embodiment.

Fig. 49 illustrates an example of FL-DMRS preemption when only FL-DMRS is configured in one slot for the eMBB UE, according to the seventh embodiment.

Fig. 50 illustrates an example of FL-DMRS preemption when only FL-DMRS is configured in one slot for the eMBB UE, according to the seventh embodiment.

Fig. 51 illustrates an example of FL-DMRS preemption when only FL-DMRS is configured in one slot for the eMBB UE, according to the seventh embodiment.

Fig. 52 illustrates an example of FL-DMRS preemption when only FL-DMRS is configured in one slot for the eMBB UE, according to the seventh embodiment.

Fig. 53 illustrates an exemplary preemption when FL-DMRS, add-DMRS and PUCCH, and/or SRS are configured for the eMBB UE, according to the second modification of the seventh embodiment.

Fig. 54 illustrates an exemplary preemption when FL-DMRS, add-DMRS and PUCCH, and/or SRS are configured for the eMBB UE, according to the second modification of the seventh embodiment.

Fig. 55 illustrates an exemplary preemption when FL-DMRS, add-DMRS and PUCCH, and/or SRS are configured for the eMBB UE, according to the second modification of the seventh embodiment.

Fig. 56 illustrates an example of FL-DMRS preemption when only FL-DMRS is configured in one slot for the eMBB UE, according to the second modification of the seventh embodiment.

Fig. 57 illustrates an exemplary displacement method when an incremental SRS is configured according to the second modification of the seventh embodiment.

Fig. 58 illustrates an exemplary preemption method when an additional PUCCH is configured, according to the second modification of the seventh embodiment.

Fig. 59 illustrates an example of SR preemption configuration according to the third modification of the seventh embodiment.

Fig. 60 illustrates an exemplary method for preempting data retransmission for URLLC UEs per slots for eMBB UEs, according to the fourth modification of the seventh embodiment.

Fig. 61 illustrates an exemplary method for preempting data retransmission for URLLC UEs per slots for eMBB UEs according to the fourth modification of the seventh embodiment.

Fig. 62 illustrates an exemplary method for preempting data retransmission for URLLC UEs per slots for eMBB UEs according to the fourth modification of the seventh embodiment.

Fig. 63 illustrates an exemplary method for preempting data retransmission for URLLC UEs per slots for eMBB UEs, according to the fourth modification of the seventh embodiment.

Fig. 64 illustrates a method for multiplexing a PDCCH for an eMBB UE with a slot for a URLCC UE according to the fifth modification of the seventh embodiment.

Fig. 65 illustrates a method for multiplexing a PDCCH for an eMBB UE with a slot for a URLLC UE according to the fifth modification of the seventh embodiment.

Fig. 66 illustrates an example of resource preemption for the PDSCH when only FL-DMRS is configured in one slot for the eMBB UE, according to the sixth modification of the seventh embodiment.

Fig. 67 illustrates an example of resource preemption for PUSCH when only FL-DMRS is configured in one slot for the eMBB UE, according to the sixth modification of the seventh embodiment.

Fig. 68 illustrates an example of configuring a plurality of incremental DMRSs in a UL, according to the sixth modification of the seventh embodiment.

Description of Implementation Options

[0058] First Embodiment

Fig. 2 is a block diagram showing the general configuration of an LTE communication system 200 as discussed in 3GPP. Here, FIG. 2. The radio access network is referred to as an evolved universal terrestrial radio access network 201 (E-UTRAN). The user equipment device 202 (hereinafter referred to as "user equipment (UE)"), which is a communication terminal device, is configured to perform radio communication with the base station device 203 (hereinafter referred to as "base station (E-UTRAN Node-B: eNB) ”) and transmits and receives signals via radio.

[0059] Here, "communication terminal device" covers not only a user equipment device such as a mobile phone terminal device, but also a stationary device such as a sensor. In the following description, "communication terminal apparatus" may simply be referred to as "communication terminal".

[0060] E-UTRAN consists of one or more base stations 203, provided that the control protocol for user equipment 202, such as radio resource control (RRC), and user planes (hereinafter also referred to as "U-planes"), such such as Packet Data Convergence Protocol (PDCP), Radio Link Control (RLC), Medium Access Control (MAC), or Physical Layer (PHY) are terminated at the base station 203.

[0061] The control protocol for radio resource control (RRC) between the user equipment 202 and the base station 203 performs, for example, broadcast, paging, and RRC connection administration. The states of the base station 203 and the user equipment 202 in RRC are classified into RRC_IDLE and RRC_CONNECTED.

[0062] In the RRC_IDLE state, public land mobile network (PLMN) selection, system information (SI) broadcast, paging, cell reselection, mobility, and the like are performed. In the RRC_CONNECTED state, the user equipment has an RRC connection, and is capable of transmitting and receiving data to and from the network. In the RRC_CONNECTED state, for example, handover (HO) and neighbor cell measurement are performed.

[0063] The base stations 203 are classified into eNBs 207 and Home-eNBs 206. Communication system 200 employs an eNB group 203-1 including a plurality of eNBs 207 and a Home-eNB group 203-2 including a plurality of Home-eNBs. 206. A system composed of an evolved packet core (EPC) which is a core network and E-UTRAN 201 which is a radio access network is referred to as an evolved packet system (EPS). EPC being a core network and E-UTAN 201 being a radio access network may be collectively referred to as a "network".

[0064] The eNB 207 is connected to an MME/S-GW unit 204 (hereinafter also referred to as an "MME unit") including a Mobility Management Entity (MME), Serving Gateway (S-GW), or MME and S-GW, through the S1 interface, and control information is reported between the eNB 207 and the MME unit 204 . A plurality of MMEs 204 may be connected to one eNB 207. The eNBs 207 are connected to each other via the X2 interface, and control information is reported between the eNBs 207.

[0065] The Home-eNB 206 is connected to the MME 204 via the S1 interface, and control information is reported between the Home-eNB 206 and the MME 204. Many Home-eNB 206 is connected to one block 204 MME. Alternatively, Home-eNBs 206 connect to MMEs 204 via a Home-eNB Gateway (HeNBGW) 205 . The home-eNB 206 is connected to the HeNBGW 205 via the S1 interface, and the HeNBGW 205 is connected to the MME unit 204 via the S1 interface.

[0066] One or more Home-eNBs 206 are connected to one HeNBGW 205 and information is communicated between them via the S1 interface. The HeNBGW 205 is connected to one or more MMEs 204 and information is communicated between them via the S1 interface.

[0067] MME units 204 and HeNBGW 205 are upper layer entities, specifically upper nodes, and manage connections between user equipment (UE) 202 and eNB 207 and Home-eNB 206, which are base stations. Blocks 204 MME configure EPC, which is the core network. Base station 203 and HeNBGW 205 configure E-UTRAN 201.

[0068] In addition, the following configuration is under study in 3GPP. An X2 interface is provided between the Home-eNBs 206. In other words, the Home-eNBs 206 are connected to each other via the X2 interface, and communication of control information is carried out between the Home-eNBs 206. The HeNBGW 205 acts as the MME 204 for the Home-eNB 206.

[0069] The interfaces between the Home-eNB 206 and the MMEs 204 are the same, which are S1 interfaces, both when the Home-eNB 206 connects to the MME 204 via the HeNBGW 205, and when it directly connects to the block 204 MME.

[0070] The base station device 203 may configure one cell or multiple cells. Each cell has a range, which is predetermined as a coverage, in which the cell can communicate with the user equipment 202, and communicate with the user equipment 202 within the coverage. In the case where the base station device 203 configures a plurality of cells, each cell is configured to communicate with the user equipment 202.

[0071] FIG. 3 is a block diagram showing the configuration of the user equipment 202 in FIG. 2. The transmission process in the user equipment 202 shown in FIG. 3. First, the transmission data buffer block 303 stores control data from the protocol processing block 301 and user data from the application block 302 . The data that is stored in the transmission data buffer block 303 is passed to the encoding block 304 and undergoes an encoding process such as error correction. There may be data output from the transmit data buffer block 303 directly to the modulation block 305 without an encoding process. The data encoded by the coding block 304 is modulated by the modulation block 305 . The modulated data is converted to a baseband signal, and the baseband signal is output to a frequency converting section 306 and then converted to a radio transmission frequency. Thereafter, the transmission signal is transmitted through the antenna 307 to the base station 203.

[0072] The user equipment 202 executes the receiving process as follows. The radio signal from the base station 203 is received through the antenna 307. The received signal is converted from a radio reception frequency into a baseband signal by a frequency conversion section 306 and then demodulated by a demodulation section 308 . The demodulated data is passed to a decoding block 309 and subjected to a decoding process such as error correction. Of the pieces of decoded data, control data is passed to the protocol processing block 301, and user data is passed to the application block 302 . A number of user equipment processes 202 are controlled by the control unit 310 . This means that although not shown in FIG. 3, the control unit 310 is connected to individual units 301 to 309.

[0073] FIG. 4 is a block diagram showing the configuration of the base station 203 in FIG. 3. The transmission process in the base station shown in FIG. 4. The EPC communication unit 401 performs data transmission and reception between the base station 203 and the EPC (such as the MME unit 204), HeNBGW 205 and the like. The other base station communication unit 402 performs data transmission and reception to and from the other base station. The EPC communication unit 401 and the other base station communication unit 402 each transmit and receive information to and from the protocol processing unit 403 . The control data from the protocol processing unit 403 and the user data and control data from the EPC communication unit 401 and the other base station communication unit 402 are stored in the transmission data buffer unit 404 .

[0074] The data stored in the transmission data buffer block 404 is passed to the encoding block 405, and then an encoding process such as error correction is performed on the data. There may be data output from the transmit data buffer block 404 directly to the modulation block 406 without an encoding process. The encoded data is modulated by modulation block 406 . The modulated data is converted to a baseband signal, and the baseband signal is output to a frequency conversion section 407 and then converted to a radio transmission frequency. Thereafter, the transmission signal is transmitted via antenna 408 to one or more user equipments 202.

[0075] The reception process in the base station 203 is executed as follows. A radio signal from one or more user equipments 202 is received via an antenna 408. The received signal is converted from a radio reception frequency to a baseband signal by a frequency conversion unit 407 and then demodulated by a demodulation unit 409 . The demodulation data is passed to decoding block 410 and then subjected to a decoding process such as error correction. Of the pieces of decoded data, control data is passed to the protocol processing unit 403, the EPC communication unit 401, or the other base station communication unit 402, and the user data is passed to the EPC communication unit 401 and the other base station communication unit 402. The control of a number of processes of the base station 203 is carried out by the block 411 control. This means that although not shown in FIG. 4, the control unit 411 is connected to the individual units 401 to 410.

[0076] FIG. 5 is a block diagram showing the configuration of the MME. Fig. 5 shows the configuration of the MME 204a in the MME block 204 shown in FIG. 2 described above. The PDN GW communication unit 501 performs data transmission and reception between the MME 204a and the PDN GW. The base station communication unit 502 performs data transmission and reception between the MME 204a and the base station 203 via the S1 interface. In the case where the data received from the PDN GW is user data, the user data is passed from the PDN GW coupler 501 to the base station coupler 502 via the user plane coupler 503, and then transmitted to one or more base stations 203. In when the data received from the base station 203 is user data, the user data is passed from the base station communicator 502 to the PDN GW communicator 501 via the user plane communicator 503, and then transmitted to the PDN GW.

[0077] In the case where the data received from the PDN GW is control data, the control data is passed from the PDN GW communication unit 501 to the control plane control unit 505 . In the case where the data received from the base station 203 is control data, the control data is passed from the base station communication unit 502 to the control plane control unit 505 .

[0078] The HeNBGW communication unit 504 is provided when a HeNBGW is provided that performs data transmission and reception between the MME 204a and the HeNBGW 205 via an interface (IF) according to the type of information. The control data received from the HeNBGW communicator 504 is passed from the HeNBGW communicator 504 to the control plane control 505 . The processing result of the control plane control block 505 is transmitted to the PDN GW via the PDN GW communication block 501 . The processing results of the control plane control unit 505 are transmitted to one or more base stations 203 via the S1 interface via the base station communication unit 502, and transmitted to one or more HeNBGW 205 via the HeNBGW communication unit 504 .

[0079] The control plane control unit 505 includes the NAS security unit 505-1, the SAE radio bearer control unit 505-2, and the idle state mobility management unit 505-3, and performs the entire process for the control plane (hereinafter also referred to as "C- plane"). The NAS security unit 505-1 provides, for example, non-access layer (NAS) message security. The SAE radio bearer control unit 505-2 manages, for example, a system architecture evolution (SAE) radio bearer. The idle state mobility management unit 505-3 performs, for example, idle state mobility management (LTE-IDLE state, which is also simply referred to as idle), idle state paging signal generation and management, adding, deleting, updating, and searching for a tracking area. one or more user equipments 202 that it serves, and administration of a list of tracking zones.

[0080] The MME 204a distributes the paging signal to one or more base stations 203. In addition, the MME 204a performs idle state mobility management. When the user equipment is in the idle state and the active state, the MME 204a administers the tracking area list. The MME 204a starts the paging protocol by sending a paging message to a cell that belongs to the tracking area in which the UE is registered. The idle mobility manager 505-3 may administer the CSG of the Home-eNB 206 to be connected to the MME 204a, the CSG ID, and the white list.

[0081] The following describes an example of a cell search method in a mobile communication system. Fig. 6 is a flowchart showing a summary of the operation that is performed by a communication terminal (UE) in the LTE communication system from cell search to idle state. When the cell search is started in Step ST601, the communication terminal synchronizes the slot timing and the frame timing through the Primary Synchronization Signal (P-SS) and Secondary Synchronization Signal (S-SS) which are transmitted from the neighboring base station.

[0082] P-SS and S-SS are collectively referred to as a synchronization signal (SS). Synchronization codes that one-to-one correspond to PCI assigned per cell are assigned to synchronization signals (SS). At present, the number of PCI is designed according to 504 options. 504 PCI variants are used for synchronization and PCI of synchronized cells are detected (indicated).

[0083] Next, in Step ST602, the user equipment detects a cell specific reference signal (CRS), which is a reference signal (RS) transmitted from the base station on a per cell basis, and measures the received reference signal power (RSRP). Codes that one-to-one correspond to PCI are used for the RS reference signal. Separation from another cell is provided by correlation using a code. The code for the RS of the cell is calculated from the PCI indicated in Step ST601 so that the RS can be detected and the power of the received RS can be measured.

[0084] Next, in Step ST603, the user equipment selects the cell with the best received RS quality, eg, the cell with the highest received RS power, i. the best cell of one or more cells that have been detected prior to Step ST602.

[0085] Next, in Step ST604, the user equipment receives the PBCH of the best cell and obtains the BCCH, which is broadcast information. A Master Information Block (MIB) containing cell configuration information is mapped to the BCCH via the PBCH. Accordingly, the MIB is obtained by receiving the BCCH by receiving the PBCH. Examples of the MIB information include a downlink (DL) system bandwidth (also referred to as a transmission bandwidth configuration (dl-bandwidth)), the number of transmission antennas, and a system frame number (SFN).

[0086] Next, in Step ST605, the user equipment receives the DL-SCH of the cell based on the cell configuration information in the MIB, to thereby obtain a System Information Block (SIB) 1 of the BCCH broadcast information. SIB1 contains cell access information, cell selection information, and scheduling information on other SIBs (SIBk; k is an integer equal to or greater than two). In addition, SIB1 contains a tracking area code (TAC).

[0087] Next, in Step ST606, the communication terminal compares the TAC of the SIB1 received in Step ST605 with the Tracking Area Identification (TAI) TAC fragment in the Tracking Area List already possessed by the communication terminal. The tracking area list is also referred to as the TAI list. TAI is identification information for identifying tracking areas and consists of a country mobile code (MCC), a mobile network code (MNC) and a tracking area code (TAC). MCC is the country code, MNC is the network code. TAC is the tracking area code number.

[0088] If the comparison result of Step ST606 indicates that the TAC received in Step ST605 is the same as the TAC included in the list of tracking areas, then the user equipment enters the cell dormant operation. If the comparison shows that the TAC received in Step ST605 is not included in the list of tracking areas, then the communication terminal requires the core network (EPC) including the MME to change the tracking area per cell to perform tracking area update (TAU) .

[0089] The core network configuring device (hereinafter also referred to as "core network side device") updates the tracking area list based on the identification number (such as UE-ID) of the communication terminal transmitted from the communication terminal along with the TAU request signal. The core network side device transmits the updated tracking area list to the communication terminal. The communication terminal rewrites (updates) the TAC list of the communication terminal based on the received tracking area list. Thereafter, the communication terminal enters the cell dormant operation.

[0090] The widespread use of smart phones and tablet terminal devices has exploded cellular radio traffic, causing fear of a shortage of radio resources worldwide. Thus, in order to increase the spectral efficiency, cell size reduction was designed to further the spatial separation.

[0091] In a conventional cell configuration, a cell configured by an eNB has a relatively wide range coverage. Conventionally, the cells are configured such that coverages of a relatively wide range of a plurality of cells configured by a plurality of macro eNBs cover a certain area.

[0092] When the cell size is reduced, the cells configured by the eNB have a narrow range coverage compared to the coverage of a cell configured by a conventional eNB. Thus, in order to cover a certain area, as in the usual case, more reduced-size eNBs are required than conventional eNBs.

[0093] In the description below, "macro cell" refers to a relatively wide coverage cell such as a cell configured by a conventional eNB, and "macro eNB" refers to an eNB that configures a macro cell. "Small cell" refers to a relatively narrow coverage cell such as a reduced cell, and "small eNB" refers to an eNB that configures a small cell.

[0094] The macro eNB may be, for example, the "global base station" described in Non-Patent Document 7.

[0095] A small eNB may be, for example, a low power node, a local node, or a hotspot. Alternatively, a small eNB can be a pico eNB that configures a pico cell, a femto eNB that configures a femto cell, a HeNB, a Remote Head Unit (RRH), a Remote Radio Unit (RRU), a Remote Radio Equipment (RRE), or a Relay Node (RN) . In yet another alternative, the small eNB may be a "local base station" or a "home base station" described in Non-Patent Document 7.

[0096] FIG. 7 shows the concept of a cell configuration in which macro eNBs and small eNBs coexist. A macro cell configured by a macro eNB has a relatively wide range coverage 701. The small cell configured by the small eNB has a coverage 702 whose range is narrower than that of the macro eNB coverage 701 (macro cell).

[0097] When multiple eNBs coexist, the cell coverage configured by the eNB may be included in the cell coverage configured by another eNB. In the cell configuration shown in FIG. 7, as indicated by "704" or "705", the small cell coverage 702 configured by the small eNB may be included in the macro cell coverage 701 configured by the macro eNB.

[0098] As indicated by "705", a coverage 702 of a plurality of, for example, two small cells may be included in a coverage 701 of one macro cell. A user equipment (UE) 703 is included, for example, in a small cell coverage 702 and communicates through the small cell.

[0099] In the cell configuration shown in FIG. 7, as indicated by "706", macro cell coverage 701 configured by macro eNBs can overlap with small cell coverages 702 configured by small eNBs in a complex manner.

[0100] As indicated by "707", the coverage 701 of a macro cell configured by a macro eNB does not necessarily overlap the coverages 702 of small cells configured by small eNBs.

[0101] In addition, as indicated by "708", coverage 702 of a large number of small cells configured by a large number of small eNBs can be configured in coverage 701 of one macro cell configured by one macro eNB.

[0102] In uplink transmission using a split radio channel using dual connectivity (DC), whether uplink data should be transmitted to a secondary node (SN) (see Non-Patent Document 12) is determined according to the capacity of the uplink data buffer communications in the UE. The master node (MN) (see Non-Patent Document 12) notifies the UE of the capacity threshold of the uplink data buffer. The UE compares the capacity of the uplink data buffer with a threshold. The UE transmits uplink data to the MN when the capacity of the uplink data buffer is less than or equal to a threshold, and transmits uplink data to the MN and SN when the capacity of the uplink data buffer is greater than the threshold.

[0103] However, for example, by applying such a method to uplink data requiring low latency, the UE performs an uplink transmission to the MN when the capacity of the uplink data buffer is less than a threshold. For example, even though the SN supports a short symbol length (duration) and the uplink transmission using the SN results in low latency characteristics, the UE has to perform the uplink transmission with the MN and has a problem that it is unable to obtain low latency characteristics.

[0104] The solution to the problem is disclosed below.

[0105] It is possible to configure with which node the UE performs uplink transmission. The MN notifies the UE of the node information for uplink transmission. The node for uplink transmission is an MN or an SN. Alternatively, nodes for uplink transmission are both MNs and SNs. For example, the base station ID may be used as node information for uplink transmission.

[0106] The node information for uplink transmission may be cell group information. The cell group information may be master cell group (MCG) and/or secondary cell group (SCG) information. The node information for uplink transmission may be cell information, and the cell information may be a cell ID. The UE indicates a cell to be used for uplink transmission.

[0107] Although the Description mainly describes a UE communication recipient as a node or a communication node, a UE communication recipient may be a cell group, a base station, or a cell, unless specifically mentioned.

[0108] Node information notification for uplink transmission should be done via RRC signaling. For example, information about nodes for uplink transmission may be included in an RRC Connection Reconfiguration (RRCConnectionReconfiguration) message to notify it. Node information notification for uplink transmission may be performed, for example, during the DC setup process.

[0109] The SN notifies the MN of information for determining which uplink transmission node from the UE is in use (hereinafter, may be referred to as uplink transmission node determination information). The uplink transmission node determination information may be latency characteristics information. The uplink transmission node determination information may be radio configuration information to be supported. The uplink transmission node determination information may be information about a communication service to be supported. The uplink transmission node determination information may be load state information or resource usage state information. The uplink transmission node determination information may be radio propagation environment information. The SN may notify the uplink transmission node determination information via Xn signaling or X2 signaling. The SN may notify the uplink transmission node determination information, for example, during the DC setup process.

[0110] The SN may notify the uplink transmission node determination information, for example, in the process of adding the SgNB. For example, the SN may include uplink transmission node determination information in the SgNB Add Request Acknowledgment to notify the information. The MN may configure an uplink transmission node for the UE at DC start. In addition, the SN may notify the uplink transmission node determination information, for example, in the process of modifying the SgNB. For example, the SN may include uplink transmission node determination information in the SgNB modification request acknowledgment to notify the information. When starting the process in response to a request from the SN, the SN may include the uplink transmission node determination information in the required modification notification of the SgNB to notify the information. The MN may configure the uplink transmission node for the UE while modifying the configuration of the SN.

[0111] Seven examples of uplink transmission node determination information are described below.

[0112] (1) Subcarrier spacing (SCS) to be supported by the SN, which may be a symbol duration.

[0113] (2) Information about whether the SN supports non-granted uplink transmission.

[0114] (3) QoS of the communication service to be supported by the SN; The QoS of the uplink communication service may be used. Information indicative of QoS may be used, such as QoS profile, QCI, latency, and packet error loss rate.

[0115] (4) SN RRC configuration.

[0116] (5) Radio configuration of the SN, such as AS configuration, MAC configuration and PHY configuration, etc.

[0117] (6) The number of symbols in the slot to be supported by the SN, which may be information about whether the SN supports a slot with fewer symbols than normal.

[0118] (7) Combinations of items (1) to (6) above.

[0119] The MN may determine an uplink transmission node for the UE. The MN may determine with which node the UE performs uplink transmission using the uplink transmission node determination information. For example, the MN determines a node with a shorter symbol duration than that of its own node as an uplink transmission node for the UE using the symbol duration information to be supported by the SN that is obtained from the SN. When the symbol durations match each other, the MN determines both NBs as uplink transmission nodes for the UE. For example, configuring uplink data requiring low latency characteristics thus allows the UE to transmit uplink data to a node that supports a shorter symbol duration and transmit uplink data with low latency.

[0120] As another example, the MN determines a node that supports non-grant transmission as an uplink transmission node for the UE using information about whether to support non-grant transmission received from the SN. When both nodes support non-granted transmission, the MN determines the nodes as uplink transmission nodes for the UE. For example, configuring uplink data requiring low latency performance thus allows the UE to perform grantless transmission that does not require any SR and transmit low latency uplink data.

[0121] The MN may request notification of the uplink transmission node determination information from the SN. The MN may notify the request via Xn signaling or X2 signaling. The MN may notify the request, for example, during the DC installation process. The MN may notify the request, for example, in the process of adding an SgNB. The MN may include the request in the SgNB add request to notify of the request. The MN may configure an uplink transmission node for the UE at DC start. The MN may notify the request, for example, in the process of modifying the SgNB. For example, the MN may include a request in an SgNB modification request to notify of the request. The MN may configure an uplink transmission node for the UE.

[0122] The UE may notify the MN of the information to determine which uplink transmission node from the UE is being used. Examples of the uplink transmission node determination information that the UE needs to notify the MN include the QoS that is required by the communication service. The uplink transmission node determination information may be the QoS required by the uplink communication service. The uplink transmission node determination information may be information indicating QoS, such as QoS profile, QCI, desired latency, and packet transmission error loss rate. The uplink transmission node determination information may include information for identifying the UE. Examples of information for identifying a UE include an identifier.

[0123] The UE may notify the uplink transmission node determination information via RRC signaling. The UE may include uplink transmission node determination information in messages such as RRC Connection Request (RRCConnectionRequest), RRC Connection Setup Complete Message (RRCConnectionSetupComplete), RRC Connection Reestablishment Request (RRCConnectionReestablishmentRequest), RRC Connection Reestablishment Complete Message (RRCConnectionReestablishmentComplete) to notify about information. By using such RRC messages as listed in these examples, the MN can use the information when configuring the DC for the UE.

[0124] The MN may request notification of the uplink transmission node determination information from the UE. The MN may notify the request via RRC signaling. The MN may include the request in messages such as an RRC Connection Setup (RRCConnectionSetup) and an RRC Connection Reestablishment (RRCConnectionReestablishment) message to notify the request. The MN may configure an uplink transmission node for the UE.

[0125] The CN may notify the MN of the information to determine which uplink transmission node from the UE is being used. Examples of the uplink transmission node determination information that the CN may notify the MN include the target UE ID and the QoS that the uplink communication service of that UE requires. The uplink transmission node determination information may be the QoS required by the uplink communication service. The uplink transmission node determination information may be information indicating QoS, such as QoS profile, QCI, desired latency, and packet transmission error loss rate. The CN may advertise the information via S1 signaling or NG-C signaling.

[0126] The MN may request the CN to notify the uplink transmission node determination information. The MN may notify the request via S1 signaling or NG-C signaling. The MN may configure an uplink transmission node for the UE.

[0127] FIG. 8 illustrates an exemplary sequence for the MN to configure for the UE which node the uplink transmission is addressed to. In the example in FIG. 8 MgNB is MN and SgNB is SN. In Step ST801, the UEs, the MgNBs, and the SgNBs perform a DC setup process using a split radio channel. In the example in FIG. 8, the uplink data transmission node is not configured according to the buffer capacity of the uplink data in the UE. During the DC setup process, the MgNB may notify the UE of information indicating a method for configuring an uplink transmission node. The MgNB can advertise the information through RRC signaling. The MgNB may include information in the RRC Connection Reconfiguration message to notify the information. The UE applies the notification-obtained configuration method. In the example in FIG. 8 The MgNB determines the uplink transmission node and notifies the UE of information indicating a method for configuring the uplink transmission node.

[0128] The example in FIG. 8 also illustrates a method for determining an uplink transmission node using SgNB SCS information. In Step ST802, the MgNB requests SCS information from the SgNB from the SgNB. In Step ST803, the SgNB notifies the MgNB of the SCS information to be supported by its own SgNB in response to a request from the MgNB. The SgNB may notify support information for each cell. The SgNB may advertise the SCS information to be maintained per cell. The SgNB may associate the SCS information with the cell ID to notify them.

[0129] In Step ST804, the MgNB compares the SCS to be supported by its own node with the SCS to be supported by the SgNB, and determines the node that supports the smaller SCS as the uplink transmission node. The example in Fig. 8 illustrates the case where the SgNB supports a smaller SCS than that of the MgNB. The MgNB defines the SgNB as the uplink transmission node.

[0130] Here, the MgNB may use the QoS information of the communication service of the UE that was obtained earlier. The MgNB may obtain QoS information of the communication service from the CN or the UE. The CN may notify the MgNB of the QoS information of the communication service in the radio bearer setup process for the communication service of the UE. The QoS information of the communication service may be included in the radio bearer information to perform the DC setup process.

[0131] The MgNB may determine as an uplink transmission node a node that supports a smaller SCS so that QoS is performed. For example, when a communication service of a UE requires low latency characteristics, the MgNB may determine an SgNB that supports a smaller SCS as an uplink transmission node. In Step ST805, the MgNB notifies the UE of information about the SgNB that is determined as the uplink transmission node.

[0132] The SgNB information includes node information, base station information, cell group information, and cell information. The MgNB associates these pieces of information to identify the SgNB with information indicating that the SgNB has been identified as an uplink transmission node to notify the UE.

[0133] In Step ST806, the UE starts the uplink transmission process for the SgNB, which is the uplink transmission node notified from the MgNB. When uplink data appears at the UE, the UE transmits an SR to the SgNB in Step ST807. The MgNB shall notify, during the DC setup process, the UE of the SR configurations in the MgNB and SgNB. The UE may transmit the SR to the cell when the MgNB notifies the cell information for uplink transmission in Step ST805.

[0134] In Step ST808, the SgNB notifies the UE of the permission for uplink communication (uplink scheduling information). In Step ST809, the UE transmits uplink data to the SgNB in accordance with the uplink grant. The UE may jointly notify the Buffer Status Report (BSR). The UE transmits uplink data by repeating the processes of Steps ST808 and ST809 until no uplink data remains.

[0135] Therefore, the UE can transmit DC uplink data to the SgNB that the MgNB has configured as an uplink transmission node regardless of the capacity of the uplink data buffer. For example, in a case where uplink data requiring low latency occurs, even when the data is small in size, the UE may transmit uplink data to an SgNB that supports a smaller SCS. With DC, a lower latency is achieved.

[0136] Previously disclosed is a method for an MN to notify a UE of uplink transmission node information. Another method is revealed. The MN may notify the UE of information for determining an uplink transmission node.

[0137] The MN needs to notify, via RRC signaling, the UE of the information to determine the uplink transmission node. For example, the MN may include information in an RRC Connection Reconfiguration (RRCConnectionReconfiguration) message to notify the information. The MN may notify the information, for example, during the DC installation process.

[0138] Seven examples of information for a UE to determine an uplink transmission node are described below.

[0139] (1) A subcarrier spacing (SCS) to be supported by each node, which may be a symbol duration.

[0140] (2) Information about whether each node supports non-granted uplink transmission.

[0141] (3) QoS of a communication service to be supported by each node; The QoS of the uplink communication service may be used. Information indicative of QoS may be used, such as QoS profile, QCI, latency, and packet error loss rate.

[0142] (4) RRC configuration of each node.

[0143] (5) The radio configuration of each node, such as AS configuration, MAC configuration and PHY configuration, etc.

[0144] (6) The number of symbols in the slot to be supported by the SN, which may be information about whether the SN supports a slot with fewer symbols than normal.

[0145] (7) Combinations of items (1) to (6) above.

[0146] These pieces of information may be associated with an MN or SN. Whether these pieces of information are from the MN or the SN can be identified. These pieces of information may be associated with each node. These pieces of information may be associated with, for example, a base station identifier. It can be identified which node or base station these pieces of information are from. These pieces of information may be associated with an MCG or an SCG. Whether these pieces of information are from the MCG or the SCG can be identified. Moreover, these pieces of information can be associated with a cell. These pieces of information may be associated with, for example, a cell ID. It can be identified which cell these pieces of information are from.

[0147] The SN may notify the UE of the information for the UE to determine the uplink transmission node. The SN may provide notification via RRC signaling. For example, the SN may include a notification in an RRC Connection Reconfiguration (RRCConnectionReconfiguration) message to provide a notification.

[0148] The information that the SN needs to notify the UE may be each node information for the UE to determine the uplink transmission node. The MN needs to notify the SN of the information from the MN for the UE to determine the uplink transmission node. The SN notifies the UE of the information for the MN and the UE at its own node to determine the uplink transmission node. Therefore, even when the radio environment of the MN is worse, the uplink transmission node can be configured using the SN, which can lead to low latency performance.

[0149] The information that the SN needs to notify the UE may be information from the SN for the UE to determine the uplink transmission node. The MN needs to notify the UE of the information from the MN for the UE to determine the uplink transmission node. This may eliminate the need for communication between the MN and SN. The information notification from each node to the UE may reflect the state of the node to the UE in a timely manner.

[0150] The UE may determine an uplink transmission node. The UE may determine to which node the uplink transmission is addressed using the information to determine the uplink transmission node. For example, the MN notifies the UE of the symbol duration information to be supported by each of the MN and SN. The UE determines a node that supports a shorter symbol duration as an uplink transmission node for the UE using symbol duration information to be supported by each node. When the symbol durations match each other, the UE determines both of the NBs as uplink transmission nodes for the UE. For example, configuring uplink data requiring low latency performance in this way allows the UE to transmit uplink data to a node that supports a shorter symbol duration and transmit uplink data with low latency.

[0151] As another example, the UE determines a node that supports non-granted transmission as an uplink transmission node for the UE using whether each node supports non-granted transmission. When both nodes support non-granted transmission, the UE designates the nodes as uplink transmission nodes for the UE. For example, configuring uplink data requiring low latency characteristics in this way allows the UE to perform an ungranted transmission that does not require any SR and transmit low latency uplink data.

[0152] The UE determines a node that supports a shorter latency as an uplink transmission node for the UE using information about the latency to be supported by each node. When the latency times coincide with each other, the UE determines both of the nodes as uplink transmission nodes for the UE. For example, configuring uplink data requiring low latency characteristics in this way allows the UE to transmit uplink data with low latency.

[0153] The UE may use the QoS required by the communication service to determine the uplink transmission node. The UE may use the QoS required by the uplink communication service. The UE may use information indicative of QoS, such as QoS profile, QCI, desired latency, and packet error loss rate. For example, the UE determines a node that supports a latency shorter than the desired latency as an uplink transmission node for the UE using information about the latency to be supported by each node. For example, configuring uplink data requiring low latency characteristics in this way allows the UE to transmit uplink data with low latency.

[0154] The UE may determine a method for determining an uplink transmission node according to an uplink communication service. Alternatively, for example, the manner in which the UE determines the uplink transmission node may be statically predefined in the standard.

[0155] It is disclosed that the MN notifies the UE of information for the UE to determine the uplink transmission node. A method for an MN to obtain exemplary uplink transmission node determination information from an SN must be applied to a method for an MN to obtain information about the SN in the above information.

[0156] FIG. 9 illustrates an exemplary sequence for a UE to determine an uplink transmission node. Because the sequence illustrated in FIG. 9 includes exactly the same steps as those of the sequence illustrated in FIG. 8, the same step numbers are assigned to the same Steps and their general description is omitted. In step ST901, a DC setting process is performed. In the example in FIG. 9, the UE is notified in the DC setup process of information indicating a method for the UE to determine an uplink transmission node. The example in Fig. 9 also illustrates a method for determining an uplink transmission node using SgNB SCS information, similar to FIG. 8.

[0157] In Step ST902, the MgNB notifies the UE of information for determining an uplink transmission node. The MgNB notifies the UE of the SCS information to be supported by its own node and the SCS information to be supported by the SgNB. The MgNB associates information for identifying the SgNB with information indicating an uplink transmission node candidate to notify the UE. Examples of information for identifying the SgNB include node information, base station information, cell group information, and cell information.

[0158] In Step ST903, the UE determines a node that supports a smaller SCS as an uplink transmission node. The example in Fig. 9 illustrates the case where the SgNB supports a smaller SCS than that of the MgNB. The UE determines the SgNB as the uplink transmission node.

[0159] Here, the UE may use the QoS information of the communication service in which the DC is configured. The UE may determine, as an uplink transmission node, a node that supports a smaller SCS so as to perform QoS. For example, when a communication service of a UE requires low latency characteristics, the UE may determine an SgNB that supports a smaller SCS as an uplink transmission node.

[0160] In Step ST806, the UE starts an uplink transmission process on an SgNB that is determined as an uplink transmission node. When uplink data appears at the UE, the UE performs uplink data transmission with the SgNB in Steps ST807 to ST809.

[0161] Therefore, the UE can transmit DC uplink data to the SgNB configured as an uplink transmission node regardless of the capacity of the uplink data buffer. For example, in the case where uplink data requiring low latency occurs, even when the data is small in size, the UE may transmit the uplink data to an SgNB that supports a smaller SCS. With DC, lower latency can be achieved.

[0162] Disclosed is a method for an MN to notify a UE of information for determining an uplink transmission node. Another method is revealed. The MN notifies the UE of a threshold for determining an uplink transmission node. The MN notifies a threshold value of an indicator other than the UE's uplink data buffer capacity as a threshold value for determining an uplink transmission node. The UE determines the uplink transmission node using the threshold.

[0163] The MN must notify the threshold for determining the uplink transmission node via RRC signaling. For example, the MN may include the threshold in an RRC Connection Reconfiguration (RRCConnectionReconfiguration) message to notify the threshold. The MN may notify the threshold, for example, during the DC setup process. The MN may notify information about a node to be used for uplink transmission when the indicator is less than (or may be less than or equal to) a threshold, and information about a node to be used for uplink transmission when the indicator is greater than or equal to (or may be greater than) the threshold value. The nodes to be used for uplink transmission can be configured in a flexible manner.

[0164] As an alternative method, the node to be used for uplink transmission when the indicator is less than a threshold and the node to be used for uplink transmission when the indicator is greater than or equal to the threshold can be statically pre-defined, for example, in the standard. Notification requires less information.

[0165] The node to be used for uplink transmission when the indicator is less than the threshold, or when the indicator is greater than or equal to the threshold, may be MN or SN. Alternatively, such nodes may be either MN or SN. The uplink transmission node information may be a base station identifier. The uplink transmission node information may be cell group information. The cell group information may be a master cell group (MCG) or a secondary cell group (SCG) information. The uplink transmission node information may be cell information, and the cell information may be cell ID. The UE indicates a cell to be used for uplink transmission.

[0166] The threshold indicator for the UE to determine the uplink transmission node may be, for example, information indicating the QoS of the uplink communication service. The indicator may be, for example, the desired latency of the uplink communication service. The indicator may be, for example, a desired packet error loss rate of an uplink communication service. The MN may configure the uplink transmission node to obtain the desired QoS for the UE using the indicator required by the uplink communication service.

[0167] For example, the MN notifies the UE of the desired latency threshold of the uplink communication service, information indicating the use of the SN as an uplink transmission node when the desired latency is below the threshold, and information indicating the use of the MN as an uplink transmission node when the desired latency is greater than or equal to a threshold. The UE transmits uplink data to the SN when the desired uplink data latency is below a threshold, and transmits uplink data to the MN when the desired uplink data latency is greater than or equal to the threshold. For example, configuring uplink data requiring low latency characteristics in this way allows the UE to transmit uplink data with low latency.

[0168] FIG. 10 and 11 illustrate an exemplary sequence for a UE to determine an uplink transmission node using a threshold. Fig. 10 and 11 illustrate an example where the threshold indicator is the desired latency. Fig. 10 and 11 are connected via the boundary location BL1011. Because the sequence illustrated in FIG. 10 and 11 includes exactly the same steps as those in the sequence illustrated in FIG. 8, the same step numbers are assigned to the same Steps, and their general description is omitted. In Step ST1000, the DC setting process is performed. In the example in FIG. 10 and 11, the UE is notified in the DC setup process of information indicating a method for the UE to determine an uplink transmission node using the threshold.

[0169] In Step ST1001, the MgNB notifies the UE of a desired latency threshold as a threshold for determining an uplink transmission node. The MgNB notifies, along with notifying the UE, information about a node to be used for uplink transmission when the desired latency is below a threshold, and information about a node to be used for uplink transmission when the desired latency is greater than or equal to threshold value. In the example in FIG. 10 and 11, SgNB is used for uplink transmission when the desired latency is below a threshold, and both MgNB and SgNB are used for uplink transmission when the desired latency is greater than or equal to the threshold. The MgNB determines these nodes using the SCS information obtained from the SgNB through Steps ST802 and ST803.

[0170] In Step ST1002, the UE determines whether the desired latency of the uplink communication service is below the threshold notified by the MgNB. When determining that the desired latency is below the threshold, in Step ST1003, the UE determines to transmit uplink data to the SgNB according to the node information notified by the MgNB in Step ST1001. When uplink data appears at the UE, the UE performs uplink data transmission with the SgNB in Steps ST1004 to ST1006.

[0171] When determining that the desired latency is greater than or equal to the threshold in Step ST1002, the UE determines in Step ST1007 to transmit uplink data to both the MgNB and the SgNB according to the notified node information MgNB at Stage ST1001. When uplink data appears at the UE, the UE performs uplink data transmission with the MgNB in Steps ST1008 to ST1010, and performs uplink data transmission with the SgNB in Steps ST1011 to ST1013.

[0172] Therefore, the UE can transmit DC uplink data to a node configured as an uplink transmission node regardless of the capacity of the uplink data buffer. For example, in a case where uplink data requiring low latency occurs, even when the data is small in size, the UE may transmit uplink data to an SgNB that supports a smaller SCS. With DC, lower latency can be achieved.

[0173] A variety of threshold values may be used. The MN notifies the UE of a plurality of thresholds for determining an uplink transmission node. The UE determines an uplink transmission node using a plurality of thresholds. For example, suppose a predefined indicator has thresholds T1 and T2. The MN may notify information about the node to be used for uplink transmission when the predetermined uplink data indicator is less than T1, the node to be used for uplink transmission when the predetermined indicator is greater than or equal to T1 and less T2, and the node to be used for uplink transmission when the predetermined indicator is greater than or equal to T2. The nodes to be used for uplink transmission can be flexibly configured. As previously described, these nodes may be statically predefined, for example in a standard. Notification requires less information.

[0174] As an alternative method using multiple thresholds, one threshold may be configured for each of the indicators. Thresholds for multiple indicators can be configured in combination. A plurality of indicators may be used to determine an uplink transmission node.

[0175] As an alternative method using multiple thresholds, multiple indicators can be configured to apply hysteresis. The state in which nodes that perform uplink transmission change within a short period of time can be reduced.

[0176] Although it is disclosed that the MN notifies the UE of the threshold for determining the uplink transmission node, the MN must determine the threshold. This can flexibly configure the threshold according to the characteristics that are required for the load state or communication service in the MN. As an alternative method, the CN may determine the threshold and notify the MN of the threshold. The MN notifies the UE of the threshold. This can flexibly configure the threshold based on the states of the plurality of nodes served by the CN. The amount of processing to determine the threshold in MN can be reduced.

[0177] The threshold value can be statically determined, for example, in the standard. The signaling for notification from the MN to the UE may be reduced. When multiple thresholds are used, the thresholds may be numbered. The number notification from the MN to the UE allows the UE to recognize the threshold corresponding to the number. The indicator may be associated with a threshold value. For example, notification of the indicator from the MN to the UE allows the UE to recognize the threshold defined in a standard, for example.

[0178] A method for changing a configuration is disclosed. While a method for the MN to notify the UE of the uplink transmission node information is disclosed, the MN may change the uplink transmission node and notify the UE of the changed uplink transmission node information. The UE transmits the uplink data to the uplink transmission node using the changed uplink transmission node information of which it has recently been notified.

[0179] Although a method for the MN to notify the UE of the uplink transmission node determination information is disclosed, the MN may change the uplink transmission node determination information and notify the UE of the changed information. The UE determines the uplink transmission node using the changed uplink transmission node determination information that it has recently been notified about.

[0180] While a method is disclosed for the MN to notify the UE of the threshold for determining the uplink transmission node, the MN may change the threshold for determining the uplink transmission node and notify the changed threshold. The UE determines the uplink transmission node using the changed threshold to determine the uplink transmission node that it has recently been notified of.

[0181] When the CN determines the threshold, the CN must change the threshold and notify the MN of the changed threshold. The MN notifies the UE of the threshold.

[0182] Therefore, the configuration can be changed. Changing the configuration in accordance with, for example, a change in state, such as the load state of the radio environment in the MN or SN, can configure the uplink transmission node more appropriate for the state change.

[0183] Such a configuration method may be configurable. The MN may determine which configuration method is used and notify the UE of information indicating the configuration method. The CN may determine which configuration method is used and notify the MN of information indicating the configuration method. The MN notifies the UE of information indicating the configuration method notified by the CN. The MN needs to notify the UE which configuration method is the most recently used when intending to change the configuration method. The UE applies the changed configuration method that it was recently notified about.

[0184] Therefore, an uplink transmission node that is more suitable for further state change can be configured. Which method is to be configured may be indicated not by a specific configuration method notification, but by a notification of information to be used for each configuration method. This may reduce the amount of information required for notification.

[0185] The above methods can be appropriately applied to multiple connectivity (MC). Two or more SNs must be used. When the UE connects to one MN and two or more SNs, an uplink transmission node may be configured from these nodes.

[0186] The above methods can be applied to split radio channels. In particular, the methods can be applied not only to the split radio bearer MCG, but also to the split radio bearer SCG. The SN may determine the base station for uplink transmission with the split radio channel SCG.

[0187] Some or all of the methods may be appropriately combined. For example, a threshold notification for determining an uplink transmission node may be combined with an information notification for determining an uplink transmission node. The UE may determine, using the uplink transmission node determination information, an uplink transmission node when the predetermined indicator is less than a threshold value, and an uplink transmission node when the predetermined indicator is greater than or equal to the threshold value. Therefore, the UE may perform an uplink transmission not with a node that has been notified or predetermined, but with a node that is more suitable for the state at each node.

[0188] Some or all of the methods, including a method for determining to which node the uplink data is transmitted according to the size of the uplink data buffer in the UE, can be appropriately combined. Example methods include determining a predetermined node as an uplink transmission node when the buffer capacity value is less than a threshold value, and determining a node that supports a shorter symbol duration as an uplink transmission node when the buffer capacity value is greater than or equal to the threshold value. . In the case where the uplink data capacity is small, even when the latency is slightly long, an increase in the amount of latency until the transmission of uplink data is completed is avoided.

[0189] The method disclosed in the first embodiment can configure a node to be a transmission recipient for uplink data from a UE. The frame structure or functions that are supported by each node may configure the node to be the recipient of the uplink data transmission from the UE. This allows uplink data to be transmitted to a node that is more optimal for the state at each node and obtain the QoS that the communication service requires.

[0190] For example, the UE may transmit data requiring low latency characteristics to a node with low latency characteristics regardless of whether the data capacity is large or small. Thus, the waiting time for uplink data transmission can be reduced.

[0191] NR requires support for Ultra Reliable Low Latency Link (URLLC). Split radio bearers may be supported for the URLLC service. The split radio bearers may be provisioned with the DRB for the URLLC service. The use of split radio channels can increase throughput. The methods disclosed in the first embodiment can be applied to a URLLC service. Applying the methods disclosed in the first embodiment to a URLLC service can result in low latency performance even with split radio channels.

[0192] If so, the split radio channels may be configured for a communication service requiring low latency performance. Therefore, the communication capacity with low latency can be increased. This can result in low latency performance.

[0193] First modification of the first embodiment

When transmitting uplink data using an SN, the UE is required to receive an uplink scheduling grant (may simply be referred to as a grant) from the SN to transmit the uplink data. To obtain an uplink grant from the SN, the UE first needs to send an SR to the SN. The UE transmits an SR with a preset periodic timing. Thus, even when uplink data appears, the UE cannot immediately transmit uplink data, and must wait for the next timing to transmit the SR.

[0194] If so, a plurality of processes must be performed from the appearance of uplink data to the SN to the transmission of uplink data to the SN, resulting in an increase in latency. Thus, even when the uplink data transmission using the SN is made configurable by applying the methods described in the first embodiment, for a communication service requiring low latency, the latency is increased as long as the uplink data are not actually transmitted to the SN.

[0195] The solution to the problem is disclosed below.

[0196] SN performs transmission without permission. Transmission without authorization in the SN is made configurable. In other words, SN supports transmission without permission. One or more cells of the SN may support non-granted transmission. The SN may support DC ungranted transmission using the SCG radio bearer.

[0197] The non-grant transmission is a UL transmission without SR and the first grant based only on the RRC configuration as the non-grant transmission configuration. This unauthorized transmission may hereinafter be referred to as the first unauthorized transmission. Examples of the RRC configuration include allocation of time-frequency resources for UL transmission, UE-specific DMRS configuration, and number of repetitions. Alternative non-grant transmission techniques include UL non-grant transmission based on both RRC configuration and L1 signaling as non-grant transmission configurations. This unauthorized transfer may hereinafter be referred to as the second unauthorized transfer. RRC configuration examples include a resource period for UL transmission and information that is related to power control. L1 configuration examples include time-frequency resource allocation for UL transmission and information for activating/deactivating uplink data transmission.

[0198] If so, allowing the SN to perform a non-grant transmission can eliminate the need for the SN to receive an SR and transmit an uplink grant in response to the SR, and reduce the latency for the SN to transmit uplink data.

[0199] The SN may support non-granted DC transmission using a split radio channel. This can create the same benefits.

[0200] Disclosed is a method for allowing an SN to perform a transmission without permission. RRC configures transmission without permission. This requires RRC signaling. However, the MN needs to notify the UE of the DC RRC signaling. The SN has a problem that it is unable to notify the UE of the SN's RRC configuration for unauthorized transmission.

[0201] The solution to the problem is disclosed below.

[0202] The SN determines whether to perform the transmission without permission. The SN configures the RRC to transmit without permission. The SN notifies the MN of its own node's RRC configuration for unauthorized transmission. The SN may advertise information to identify its own node. The SN may associate the RRC configuration of the SN to broadcast without permission with its own node identification information to notify them. Examples of information for identifying one's own node include an identifier. The SN may notify the MN of the information to identify the UE that configures the transmission without permission. The SN may associate the SN's RRC configuration for unauthorized transmission with the UE identification information to notify them. Examples of information for identifying a UE include an identifier. The SN may notify the MN via X2 or Xn signaling.

[0203] The MN notifies the UE of the SN's RRC configuration that was received from the SN. The MN may advertise the information to identify the SN. Once having notified the MN of the RRC configuration made by the SN for unauthorized transmission, the SN may notify the UE of the RRC configuration for unauthorized transmission at the DC. The UE may receive the RRC configuration from the SN for transmission without permission. The UE may perform a non-grant transmission to the SN by configuring the SN's RRC for non-grant transmission.

[0204] FIG. 12 and 13 illustrate an exemplary sequence for an SN to perform an unauthorized transmission with a split radio channel. Fig. 12 and 13 are connected via boundary location BL1213. Fig. 12 and 13 illustrate the first transmission without permission. Because the sequence illustrated in FIG. 12 and 13 includes exactly the same steps as those of the sequence illustrated in FIG. 8, the same step numbers are assigned to the same Steps, and their general description is omitted.

[0205] In Steps ST801 to ST809, the UE performs uplink data transmission with the SgNB at DC. In Step ST1101, the SgNB determines to perform a grantless transmission for the UE. The SgNB may determine whether to perform an unauthorized transmission based on, for example, the radio bearer information notified to the MgNB during DC setup, or the load state or radio resource usage state of the SgNB. For example, when the communication bandwidth requirement for uplink data transmission by the radio bearer of the UE is not met and the SgNB has sufficient radio resources, the SgNB determines to perform the transmission without permission for the UE.

[0206] The SgNB that determined to perform the non-grant transmission for the UE in Step ST1101 configures the non-grant transmission for the UE in Step ST1102. In Step ST1103, the SgNB notifies the MgNB of the configuration for unauthorized transmission. The SgNB associates the configuration for non-grant transmission with identification information of the UE that configures the non-grant transmission, eg, the UE ID, to notify the MgNB. In Step ST1104, the MgNB notifies the UE of the configuration of the SgNB for unauthorized transmission.

[0207] In Step ST1105, the UE configures a grantless transmission for the SgNB. When uplink data appears at the UE, the UE transmits, in Step ST1106, the uplink data to the SgNB with the SgNB's configuration for non-granted transmission, which was received in Step ST1104, without transmitting an SR to the SgNB. The UE may also transmit the BSR.

[0208] Upon receiving the BSR, the SgNB transmits an uplink grant to the UE in Step ST1107. In Step ST1108, the UE transmits uplink data to the SgNB in accordance with the received uplink grant. The UE may also transmit the BSR. If so, then the UE and the SgNB perform uplink data transmission.

[0209] This allows the UE to receive the configuration from the SgNB for transmission without permission on the DC. The UE may perform a non-grant transmission to the SgNB by configuring the SgNB for non-grant transmission. Since this eliminates the transmission of the SR and the first uplink grant in response to the SR, lower latency can be achieved in uplink communication.

[0210] The following discloses the case where part of the configuration for the non-grant transmission is performed in RRC, and the remainder of the configuration is performed in L1, similar to the second non-grant transmission. The MN needs to notify the UE of the RRC configuration and the L1 configuration of the SN for ungranted transmission. The MN needs to notify the UE of the RRC configuration of the SN via RRC signaling, and of the L1 configuration via L1 signaling. The MN may include L1 signaling in the DCI addressed from the MN to the UE to notify of the L1 signaling.

[0211] The SN must notify the MN of the RRC configuration and the SN's L1 configuration for unauthorized transmission before the MN notifies the UE of these configurations. The SN may advertise information to identify its own node. The SN may notify the MN of the information to identify the UE that configures the transmission without permission. The SN may associate the RRC configuration and the SN's L1 configuration for the non-permission configuration with the UE identification information to notify them. The SN may notify the MN via X2 or Xn signaling.

[0212] Therefore, the SN may notify the UE of the RRC configuration and the L1 configuration for DC non-grant transmission for the second non-grant transmission. The UE may receive the RRC configuration and the L1 configuration from the SN for transmission without permission. The UE may receive the RRC configuration and the L1 configuration from the SN for transmission without permission. The UE may perform unauthorized transmission to the SN with the RRC configuration and L1 configuration of the SN for unauthorized transmission.

[0213] Disclosed is an alternative method for a second transmission without permission. The SN may notify the UE of the SN's L1 configuration for transmission without permission. The MN must notify the UE of the SN's RRC configuration for unauthorized transmission via RRC signaling, while the SN must notify the UE of the SN's L1 configuration for unauthorized transmission via L1 signaling. The SN may include L1 signaling in DCI addressed from the SN to the UE to notify of the L1 signaling.

[0214] The SN must notify the MN of the SN's RRC configuration for unauthorized transmission before the MN notifies the UE of the RRC configuration. The SN shall notify the MN via X2 or Xn signaling.

[0215] This eliminates the need for notification of the L1 configuration of the SN for unauthorized transmission by the MN. In this way, the waiting time required for signaling Xn or X2 from the SN to the MN and the processing waiting time when the load of the MN is high can be reduced. L1 configuration from SN to UE can be performed with low latency. For example, the SN may timely instruct the UE to activate/deactivate the transmission without a grant with a low latency.

[0216] FIG. 14 and 15 illustrate an exemplary sequence for an SN to perform an unauthorized transmission with a split radio channel. Fig. 14 and 15 are connected via boundary location BL1415. Fig. 14 and 15 illustrate the second transmission without permission. Because the sequence illustrated in FIG. 14 and 15 includes exactly the same steps as those of the sequence illustrated in FIG. 12 and 13, the same step numbers are assigned to the same Steps and their general description is omitted.

[0217] The UE that configured the non-grant transmission for the SgNB in Step ST1105 receives the L1 signaling from the SgNB. In step ST1201, the SgNB notifies the UE of the L1 configuration for unauthorized transmission via L1 signaling. A physical dedicated control channel obtained by including an L1 configuration in the DCI may be used as L1 signaling. When uplink data appears at the UE, the UE transmits, without transmitting an SR to the SgNB, the uplink data to the SgNB in Step ST1106 with the SgNB configuration for non-granted transmission that was received in Step ST1104, and the SgNB's configuration for non-granted transmission. permission that was accepted at Step ST1201. The UE may also transmit the BSR.

[0218] Upon receiving the BSR, the SgNB transmits an uplink grant to the UE in Step ST1107. In Step ST1108, the UE transmits uplink data to the SgNB in accordance with the received uplink grant. The UE may also transmit the BSR. If so, then the UE and the SgNB perform uplink data transmission.

[0219] This allows the UE to receive both the RRC configuration and the L1 configuration from the SgNB for grantless transmission on DC. The UE can perform unauthorized transmission to the SgNB with these configurations at the SgNB for unauthorized transmission. Since this eliminates the transmission of the SR and the first uplink grant in response to the SR, lower latency can be achieved in uplink communication.

[0220] In the above method, the UE is notified of the RRC configuration of the SN for unauthorized transmission by the MN. Another method is revealed. The SN may notify the UE of the SN's RRC configuration for transmission without permission. This can reduce the latency that is required for Xn or X2 signaling from the SN to the MN and the processing latency when the MN load is high. The UE may perform the transmission without permission to the SN earlier.

[0221] The SN may notify both the UE and the MN of the SN's RRC configuration for transmission without permission. This allows the MN to recognize the RRC configuration of the SN for transmission without permission.

[0222] The SN may notify the UE of some or all of the SN's RRC configuration for transmission without permission. For example, the SN notifies the UE by the MN of the parameters requiring adjustment between the MN and the SN, and notifies the UE of the parameters that do not require any adjustment between the MN and the SN.

[0223] For example, the SN may notify the MN of the power configuration information for transmitting uplink data when transmitting without permission, and then the MN may notify the UE of such information. For example, since the MN can recognize, via the split radio channel, the uplink data transmission power configuration information of the SN, the MN can adjust the transmission power for the MN and the transmission power for the SN. For example, the MN may configure the transmit power for the MN according to the power with which the UE can transmit.

[0224] MN can make an adjustment with SN. The MN may notify the SN of the request to change the RRC configuration received from the SN. The MN may include in the notification the RRC configuration that is required by the MN. SN changes the configuration and notifies MN of the result. For example, the MN notifies the SN of the desired transmit power configuration in order to reserve the power needed to transmit from the UE to the MN. The SN configures the uplink transmission power for unauthorized transmission according to the desired transmission power, and notifies the MN of the configuration.

[0225] The MN notifies the UE of the RRC configuration resulting from the adjustment with the SN. This allows MN to make adjustments between MN and SN.

[0226] A method for changing a configuration is disclosed. The SN notifies the MN of the SN's RRC configuration changed for unauthorized transmission. The SN may advertise the RRC configuration and the L1 configuration. The SN may advertise information to identify its own node. The SN may notify information about the UE that changes the configuration for transmission without permission. The SN may associate the changed configuration with information about the UE that changes the configuration for transmission without permission to notify them. The MN notifies the UE of the changed RRC configuration of the SN for unauthorized transmission. MN notifies RRC configuration and L1 configuration. The RRC configuration and the L1 configuration may be changed with the same timing or different timings. This makes configurations flexible. The SN can only notify the MN of a changed configuration or a changed configuration parameter.

[0227] The UE changes only the notified configuration or the notified configuration parameter. This may reduce the amount of signaling or the amount of information needed for notification. The UE may perform unauthorized transmission to the SN with the modified RRC configuration and/or modified L1 configuration of the SN for unauthorized transmission that it has recently been notified of.

[0228] The SN may notify the UE of the changed L1 configuration of the SN for transmission without permission. The SN may advertise the RRC configuration and the L1 configuration. The RRC configuration and the L1 configuration may be changed with the same timing or with different timings. This makes configurations flexible. The SN may only notify the UE of a changed configuration or a changed configuration parameter. The UE only changes the notified configuration or the notified configuration parameter. This may reduce the amount of signaling or the amount of information needed for notification.

[0229] The UE may perform a non-grant transmission to the SN using the modified RRC configuration and/or the modified L1 configuration of the SN for the non-grant transmission that it has recently been notified about.

[0230] A method for canceling a configuration is disclosed. The SN notifies the MN to deconfigure the SN for transmission without permission. The SN may advertise information to identify its own node. The SN may notify information about the UE that deconfigures for transmission without permission. The SN may associate the SN's unconfiguration for unauthorized transmission with information about the UE that deconfigures for unauthorized transmission to notify them. The MN notifies the UE to deconfigure the SN for transmission without permission. Upon receiving the notification to cancel, the UE deconfigures the SN to transmit without permission. The SN may notify the UE to deconfigure the SN for transmission without permission. Upon receiving the notification to cancel, the UE deconfigures the SN to transmit without permission.

[0231] The MN may request the SN to configure the transmission without permission from the SN. In addition, the MN may notify the SN of the configuration information for unauthorized transmission that the MN requests from the SN. The MN may advertise information to identify its own node. The MN may notify the SN of information to identify the UE that configures the transmission without permission. The MN may associate the request for changing the transmission without grant with the identification information of the UE that configures the transmission without grant to notify them. The MN may notify the request via Xn signaling or X2 signaling.

[0232] The configuration information for permissive transmission may be an RRC configuration parameter, an L1 configuration parameter, or a combination of an RRC configuration parameter and an L1 configuration parameter. The unauthorized transmission configuration information may be part or all of the unauthorized transmission configuration parameter. The configuration information for non-grant transmission may be information indicating either the first non-grant transmission or the second non-grant transmission. The proxy configuration information that the MN requests from the SN may be a proxy configuration that the MN has made at its own node.

[0233] This can flexibly configure the details that the MN requests from the SN. The MN may request a more appropriate configuration according to, for example, the load state of the MN or the radio propagation environment between the MN and the UE.

[0234] The SN determines the configuration for the transmission without grant for the target UE in its own node, in response to the configuration of the request for transmission without grant, which notified the MN. The SN may configure transmission without authorization. Alternatively, the SN may use the configuration information for the unauthorized transfer notified to the MN. Applying the configuration information for unauthorized transmission that is requested by the MN can retrieve the configuration considering, for example, the load state of the MN or the radio propagation environment between the MN and the UE.

[0235] The SN must configure the configuration information for unauthorized transmission that the MN does not notify. This provides the configuration required for transmission without permission. Thus, the SN may perform the transmission without permission for the UE.

[0236] The UE may notify the SN of information indicating the QoS that the communication service requires. The UE may notify information indicating the QoS required by the uplink communication service. The UE may notify information for identifying its own UE. The UE may notify the MN of the information, and then the MN may notify the SN of the information.

[0237] As an alternative method, the SN may derive, using information indicating the QoS required by the downlink communication service, information indicating the QoS required by the uplink communication service. For example, suppose information indicating the QoS required by the downlink communication service as information indicating the QoS required by the uplink communication service corresponding to the downlink communication service. Therefore, the signaling for notification of information indicating QoS from the UE to the SN can be reduced.

[0238] The SN may determine with the help of the information whether to configure the transmission without permission in its own node. For example, the SN determines whether to configure the UE's non-grant transmission with the desired latency required by the UE's uplink service and the load state of its own node, such as the amount of unused resources.

[0239] For example, when the amount of unused resources is greater than a predetermined value, the SN configures the transmission without permission for the UE. When the amount of unused resources is less than a predetermined value and the required latency is less than a predetermined time, the SN configures the transmission without permission for the UE. When the amount of unused resources is less than a predetermined value and the desired latency is greater than a predetermined time, the SN does not configure transmission without permission for the UE. If so, then the SN may determine whether to configure the transmission without permission using the QoS information required by the communication service of the UE.

[0240] Upon receiving a request to configure a non-grant transmission from the MN, the SN may notify the MN whether to configure a non-grant transmission for the target UE. The SN may notify an acknowledgment (Ack) or rejection (rejection) as a response to a request to configure transmission without permission. The SN may advertise information to identify its own node. The SN may notify information for identifying the UE. The SN may associate the response to the request to configure the transmission without permission with the information to identify the UE to notify them.

[0241] When the SN configures a grantless transmission for the UE, the SN notifies the MN of the Ack. The MN may recognize that the SN has configured a grantless transmission for the target UE. The above method can be applied to a method for having the SN notify the MN or the UE of the configuration for unauthorized transmission. The UE can perform a non-grant transmission to the SN by configuring the SN for non-grant transmission. When the SN notifies the MN of the SN's configuration for unauthorized transmission, the notification may mean Ack. This may reduce the alarm.

[0242] When the SN notifies the MN of the rejection, the notification may include reason information. Examples of reason information include not being able to transmit without authorization, lack of authority to transmit without authorization, congestion, and lack of resources. This allows the MN to recognize the reason why the SN cannot configure transmission without permission for the target UE. For example, the MN may switch the DC configuration to another SN. As another example, the MN may perform a switch process to, in a different SN, a UE with a higher desired latency among the UEs in which the DC has been configured using the SN.

[0243] When the SN notifies the MN of the rejection, the notification may include a wait time (wait timer). This allows the MN to re-execute the process of requesting the transmission configuration from the SN without permission after the timeout has elapsed. Therefore, flexible processing can be performed as a system.

[0244] FIG. 16 and 17 illustrate an exemplary sequence for an SN to perform an unauthorized transmission with a split radio channel. Fig. 16 and 17 are connected via boundary location BL1617. Fig. 16 and 17 illustrate the case where the MN requests the SN to configure transmission without permission. Because the sequence illustrated in FIG. 16 and 17 includes exactly the same steps as those in the sequence illustrated in FIG. 12 and 13, the same step numbers are assigned to the same Steps and their general description is omitted.

[0245] In Steps ST801 to ST809, the UE performs uplink data transmission with the SgNB at DC. In Step ST1301, the MgNB determines that the SgNB is performing a transmission without permission for the UE. The MgNB determines to request the SgNB to configure a non-grant transmission based on, for example, the QoS information for the uplink communication of the UE, the load state of the SgNB, or the radio resource usage state of the SgNB.

[0246] For example, the MgNB determines to request the SgNB to configure permissive transmission based on the QoS information for the uplink communication of the UE and the load state of the SgNB. The MgNB should appropriately obtain from the UE and the SgNB the QoS information for the uplink communication of the UE and the load state of the SgNB. The MgNB may obtain QoS information for uplink communication from the UE, for example, in the manner disclosed in FIG. 8. The MgNB must receive the load state of the SgNB from the SgNB. For example, the MgNB queries the load state of the SgNB and the SgNB notifies the MgNB of its own node's load state. The MgNB can obtain the load state from the SgNB by properly performing this process.

[0247] For example, in the case where the UE's desired uplink latency is less than a predetermined value, while the SgNB's load state is greater than the predetermined value, the MgNB does not request a transmission configuration without permission. However, when the load state of the SgNB is below a predetermined value, the MgNB requests a configuration for transmission without permission. If so, then the MgNB should determine to request the SgNB to configure the transfer without permission in the SgNB.

[0248] The MgNB that has determined that the SgNB is performing a non-grant transmission for the UE in Step ST1301 requests the SgNB to configure a non-grant transmission in Step ST1302. The MgNB may notify information for identifying a target UE and information indicating a request to configure transmission without permission. In step ST1303, the SgNB configures a grantless transmission for the UE. In Step ST1304, the SgNB notifies the MgNB of the response to the request to configure transmission without permission. The SgNB may notify the information for identifying the target UE and the response to the request to configure the transmission without permission. Fig. 16 and 17 illustrate the acknowledgment (Ack) case.

[0249] The SgNB includes the configuration information of the SgNB for unauthorized transmission in the response message that it notifies in Step ST1304 (Ungranted Transmission Configuration Request Response Message). Therefore, the MgNB may receive the configuration from the SgNB to transmit without permission for the UE. In Step ST1104, the MgNB notifies the UE of the configuration information of the SgNB for unauthorized transmission. In Steps ST1105 to ST1108, the UE configures a grantless transmission for the SgNB. When uplink data appears in the UE, an unauthorized transmission is performed between the UE and the SgNB.

[0250] Therefore, lower DC latency can be achieved. The MgNB may request the SgNB to configure the transfer without permission. The MgNB, being a C-Plane node for the UE, may manage the configuration for transmission without permission. This can avoid complexity in management.

[0251] Unauthorized transmission may be configured for MNs and SNs. The unauthorized transmission may be differently configured between the MN and the SN.

[0252] FIG. 18 and 19 illustrate an exemplary sequence for MNs and SNs to perform unauthorized transmission with a split radio channel. Fig. 18 and 19 are connected via boundary location BL1819. Because the sequence illustrated in FIG. 18 and 19 includes exactly the same steps as those in the sequence illustrated in FIG. 16 and 17, the same step numbers are assigned to the same Steps and their general description is omitted.

[0253] In Step ST1400, the UE, MgNB, and SgNB perform a DC setup process. On FIG. 18 and 19, the UE is in uplink communication with both MgNB and SgNB. In Steps ST1401 to ST1403, the UE performs uplink communication with the MgNB. In Steps ST1404 to ST1406, the UE performs uplink communication with the SgNB.

[0254] In Step ST1407, the MgNB determines to perform an unauthorized transmission for the UE at its own node. For example, SgNB should be substituted for MgNB in the determination method disclosed in FIG. 16 and 17 to be used as a determination method. The MgNB determines to request a configuration for permissive transmission based on, for example, the QoS information for uplink communication of the UE, the load state of the MgNB, or the radio resource usage state of the MgNB. In Step ST1408, the MgNB notifies the UE of the configuration for unauthorized transmission at its own node. In Step ST1409, the UE configures a grantless transmission for the MgNB. In Steps ST1410 to ST1412, the UE and the MgNB perform an ungranted transmission.

[0255] In Step ST1301, the MgNB determines to request the SgNB to perform the transmission without granting the UE. For example, the determination method disclosed in FIG. 16 and 17 must be applied for this method of determination. The MgNB that determined that the SgNB performs the non-grant transmission for the UE in Step ST1301 requests the SgNB to configure the non-grant transmission in Step ST1302. When uplink data appears at the UE, the UE and the SgNB perform an ungranted transmission in Steps ST1106 to ST1108.

[0256] The MgNB's determination to configure a non-grant transmission may be reversed in order to the SgNB's determination to configure a non-grant transmission. A number of processes from determining to configure each transfer without authorization can be performed in reverse. MgNB and SgNB can simultaneously determine the transmission configuration without permission. MgNB and SgNB can perform a number of processes in parallel from determining what to configure the respective transfers without permission.

[0257] Therefore, both the MgNB and the SgNB can perform an ungranted transmission on DC. Using both nodes can increase throughput. Since the use of unauthorized transmission at both nodes can achieve lower latency, throughput can be further increased.

[0258] Although it is disclosed that the MN requests the SN to configure the transfer without permission in the SN, the MN may issue an instruction to the SN to configure the transfer without permission in the SN, as an alternative method. Similar to the method for requesting a configuration, the MN may notify the SN of the configuration information for unauthorized transmission that the MN requests from the SN. The MN may advertise information to identify its own node. The MN may notify the SN of the information to identify the UE that configures the transmission without permission. The MN may associate the non-granted transmission configuration instruction with the UE identification information to notify them. The MN may notify the instruction via Xn signaling or Xn signaling.

[0259] The SN may notify the MN, for example, of the SN's load information or uplink resource utilization status. The SN may advertise information to identify its own node. For example, the MN determines using these pieces of information whether to configure the non-grant transmission in the SN for the communication service of the target UE, and instructs the SN to configure the non-grant transmission when determining to configure the non-grant transmission. When the UE notifies the MN of the QoS of the communication service of the UE, the MN may further determine, using the QoS information, whether to configure the transmission without permission in the SN.

[0260] Upon receiving an instruction to configure a non-grant transmission from the MN, the SN configures a non-grant transmission for the target UE. When the MN has notified the SN of the configuration information for the unauthorized transmission, the SN may use the configuration received from the MN as the configuration for the unauthorized transmission. Therefore, the MN can control whether the SN configures the grantless transmission for the UE in which the DC is configured.

[0261] Disclosed is a method for requesting a configuration change. The MN notifies the SN of the SN's reconfiguration request for transfer without permission. For example, when the uplink communication of the UE does not perform the desired QoS, the MgNB determines to request the SgNB to configure the transmission without permission within a shorter period. The MN may notify the SN of information about the UE that is requesting a configuration change for transmission without permission. The MN may associate the configuration change request with information about the UE to notify them. The SN may reconfigure for transmission without permission for the target UE, subject to the reconfiguration request. The SN notifies the MN of the changed configuration for transmission without authorization. The MN notifies the UE of the changed configuration at the SN for unauthorized transmission.

[0262] The UE only changes the notified configuration or the notified configuration parameter. This may reduce the amount of signaling or the amount of information needed for notification. The UE may perform the unauthorized transmission to the SN using the modified configuration at the SN for the unauthorized transmission that it has recently been notified of. The SN may notify the UE of the changed configuration for transmission without permission. The UE may perform the unauthorized transmission to the SN using the modified configuration at the SN for the unauthorized transmission that it has recently been notified of.

[0263] Disclosed is a method for requesting a deconfiguration. The MN notifies the SN of the deconfiguration for unauthorized transmission. For example, when the UE's uplink communication performs the desired QoS, the MgNB determines to request the SgNB to deconfigure for unauthorized transmission. The MN may notify the information about the UE that requests deconfiguration for transmission without permission. The MN may associate deconfiguration for unauthorized transmission with information about the UE that requests the deconfiguration for unauthorized transmission to notify them. The SN may deconfigure for transmission without permission for the target UE, subject to the deconfiguration request. The SN notifies the MN to deconfigure for unauthorized transmission. The MN notifies the UE to deconfigure the SN for unauthorized transmission. The SN may notify the UE to deconfigure the SN for unauthorized transmission. Upon receiving the cancellation notification, the UE deconfigures the SN to transmit without permission.

[0264] The UE may request the MN to configure the transmission without permission for the MN and/or SN. The UE may request the SN to configure transmission without permission for the SN and/or MN. The UE may provide information indicating a request to configure transmission without permission to notify the information. The UE may include its own UE ID in the request to configure the transmission without permission. The UE may include the identity of the node that requests the non-grant transmission configuration in the non-grant transmission configuration request to notify the identifier. The UE may associate the node ID with the request to configure the transmission without permission to notify them. The UE must make the request via RRC signaling. Alternatively, the UE may make the request via MAC signaling. The UE may notify the low error rate request earlier. Alternatively, the UE may make the request via L1/L2 signaling. The UE may notify the request earlier.

[0265] When the node that received the non-grant transmission configuration request from the UE is different from the node that configures the non-grant transmission, its own node requests the node that configures the non-grant transmission to configure the non-grant transmission. Notification between nodes must be done via X2 or Xn signaling.

[0266] For example, when the UE communicates with the SN, the UE determines whether the QoS (eg, desired latency) required by the communication is performed. For example, the UE needs to measure the QoS (eg, latency) of the link. When the required QoS is not met, the UE requests a transmission configuration without permission. Therefore, the UE may request the corresponding node to configure the transmission without permission according to the communication state in the UE. This allows the UE to flexibly adapt to the changing communication state and perform the required QoS.

[0267] FIG. 20 and 21 illustrate an exemplary sequence for an SN to perform an unauthorized transmission with a split radio channel. Fig. 20 and 21 are connected via the boundary location BL2021. Fig. 20 and 21 illustrate the case where the UE requests the MN to configure transmission without permission. Because the sequence illustrated in FIG. 20 and 21 includes exactly the same steps as those in the sequence illustrated in FIG. 18 and 19, the same step numbers are assigned to the same Steps and their general description is omitted.

[0268] In Step ST1501, the UE determines to request the SgNB to configure the transmission without permission. The UE determines the request using, for example, the QoS information for the uplink communication of the UE and the QoS value in the actual communication. The UE may determine the request using the support information of the MgNB and the SgNB, such as the SCS information to be supported.

[0269] When using the QoS value in the actual communication, the UE must measure the QoS value in the actual communication. The UE needs to measure, for example, the latency of the uplink packet data, the packet loss, or the bit rate in the actual communication. The UE compares the actually measured QoS value with the desired QoS information, and determines to request the SgNB to configure a non-granted transmission when the actual measured QoS value is less than the desired QoS information. The UE may determine to request which node to configure the permissionless transmission using the support information from the MgNB and SgNB. The method disclosed in the first embodiment, i.e. a method for the MgNB to notify the UE of information for determining the uplink transmission node must be applied to the method for the UE to obtain support information from the MgNB and the SgNB.

[0270] FIG. 20 and 21 illustrate the determination to request the SgNB to configure the transfer without permission. In Step ST1502, the UE notifies the MgNB of the request to configure transmission without permission in the SgNB. The UE must notify the MgNB of its own UE identification information and the SgNB identification information. The MgNB can recognize which SgNB is being asked to configure the transmission without permission for which UE.

[0271] Upon receiving the request to configure transmission without permission in the SgNB in Step ST1502, the MgNB determines to request the SgNB to configure transmission without permission in Step ST1503. In Step ST1302, the MgNB notifies the SgNB of the request to configure transmission without permission. The MgNB that determined that the SgNB performs the unauthorized transmission for the UE in Step ST1503 requests the SgNB to configure the unauthorized transmission in Step ST1302. When uplink data appears at the UE, the UE and the SgNB perform an ungranted transmission in Steps ST1106 to ST1108.

[0272] Therefore, lower DC latency can be achieved. The state at the UE, for example, the actual measured QoS value, can be used to determine a request to configure the transmission without permission. This promptly makes the unauthorized transmission configurable according to the state in the UE, and makes the transmission method configurable according to the state in the UE.

[0273] The CN may request the MN to configure the transmission without permission for the MN and/or SN. The CN may request the SN to configure the transmission without permission for the SN and/or the MN. The CN may provide information to indicate a request to configure a transmission without permission to notify the information. The CN may advertise information to identify the SN and/or the MN. The CN may include the identifier of the UE that configures the non-grant transmission in the request to configure the non-grant transmission. The CN may also include in the request the identifier of the node that requests the configuration of the transfer without permission to notify the identifier. The CN may associate the node ID with the request to configure the transfer without permission to notify them. The CN may include PDU session information and/or QoS flow information in the request to configure permissive transmission to notify such information. The CN shall make the request via S1 or NG-C signaling.

[0074] When the node that received the non-grant transmission configuration request from the CN is different from the node that configures the non-grant transmission, its own node requests the node that configures the non-grant transmission to configure the non-grant transmission. Notification between nodes must be done via X2 or Xn signaling.

[0275] For example, when the UE is in uplink communication with the SN, the CN determines whether the QoS (eg, desired latency) required by the communication is performed. For example, the CN needs to measure the QoS (eg, latency) of the link. When the required QoS is not met, the CN requests a transfer configuration without permission. Therefore, the CN may request the corresponding node to configure the transmission without permission according to the communication state in the UE. This allows the CN to flexibly adapt to the changing link state and perform the required QoS.

[0276] FIG. 22 and 23 illustrate an exemplary sequence for an SN to perform an unauthorized transmission with a split radio channel. Fig. 22 and 23 are connected via boundary location BL2223. Fig. 22 and 23 illustrate the case where the CN requests the MN to configure the transmission without permission. Because the sequence illustrated in FIG. 22 and 23 includes exactly the same steps as those in the sequence illustrated in FIG. 20 and 21, the same step numbers are assigned to the same Steps and their general description is omitted.

[0277] In Step ST1601, the CN determines to request the MgNB and the SgNB to configure the transmission without permission. The CN measures, for example, the throughput in the actual uplink communication with the target UE and determines the request using the result of the measurement. The CN may determine the request using the support information of the MgNB and SgNB, eg, information about the SCS to be supported.

[0278] For example, when the throughput in the actual uplink communication is less than the desired value, the CN determines to request the MgNB and SgNB to configure the transmission without permission. The CN may determine which node is requested to configure the transfer without permission using the support information of the MgNB and SgNB. The method for the MgNB to notify the CN in advance of the uplink transmission node determination information can be applied to the method for the CN to obtain the support information from the MgNB and the SgNB. Notification must be made via S1 or NG-C signaling.

[0279] FIG. 22 and 23 illustrate the determination to request the MgNB and SgNB to configure the transfer without permission. In Step ST1602, the CN notifies the MgNB of the request to configure a transfer without permission in the MgNB and the SgNB. The CN needs to notify the MgNB of the information for identifying the target UE and the information for identifying the SgNB. The MgNB can recognize which SgNB is requested to configure the transmission without permission, for which UE.

[0280] In Step ST1602, the CN may notify some or all of the configuration information for transmission without permission from the MgNB and SgNB. For example, the CN configures the same period and the same resource offset for unauthorized transmission for both the MgNB and the SgNB, and notifies the configuration. This can make the timing for the MgNB to transmit without granting the same as that of the SgNB, and reduce the increase in latency amount that is caused by different timings.

[0281] Upon receiving a request to configure a non-grant transmission in the MgNB and an SgNB in Step ST1602, the MgNB configures a non-grant transmission in the MgNB. In Step ST1603, the MgNB determines to request the SgNB to configure transmission without permission. In Step ST1302, the MgNB notifies the SgNB of the request to configure transmission without permission.

[0282] In Step ST1304, the MgNB receives information for identifying the target UE and information for indicating Ack from the SgNB. The MgNB also receives configuration information for transmission without permission from the SgNB. In Step ST1604, the MgNB notifies the UE of its own node's unauthorized transmission configuration information and the SgNB's unauthorized transmission configuration information.

[0283] The MgNB that has acknowledged the successful notification in Step ST1604 notifies the CN of the completion of the transmission configuration without authorization in Step ST1605. The MgNB may include in the termination notification information for identifying the target UE and information for identifying the node for which the unauthorized transmission has been configured. Therefore, the CN recognizes that the unauthorized transmission has been configured in the MgNB and SgNB.

[0284] Upon receiving the configurations of the MgNB and SgNB for non-grant transmission in Step ST1604, the UE configures non-grant transmission for the MgNB and SgNB in Step ST1606. When uplink data appears at the UE, the UE and the MgNB perform an ungranted transmission in Steps ST1607 to ST1609. Then, the UE and the SgNB perform an ungranted transmission in Steps ST1610 to ST1612.

[0285] Therefore, lower latency can be achieved with DC. The CN requests each node to configure the non-grant transmission and configures some or all of the configuration for the non-grant transmission so that the latency in uplink communication can be reduced as a system.

[0286] The CN may notify the MN or SN of the configuration for transmission without permission at each node. The CN may notify the node from which the unauthorized transfer configuration is requested of the unauthorized transfer configuration along with the unauthorized transfer configuration request that the CN notifies the MN or the SN, or include the unauthorized transfer configuration in the request to notify the node of configuration. When the node that received the non-grant transmission configuration request from the CN is different from the node that configures the non-permission transmission, its own node can notify the node that configures the non-permit transmission of the configuration for the non-permit transmission.

[0287] The CN may notify some or all of the configuration for transmission without permission. When notifying a plurality of nodes of the configuration for unauthorized transmission, the CN may configure some or all of the configuration for unauthorized transmission sequentially among the plurality of nodes to notify the configuration. The node that the CN has notified of the configuration for unauthorized transmission configures its own node's unauthorized transmission based on the configuration.

[0288] For example, the CN requests the MN and the SN to configure the transmission without permission. Here, the same non-grant transmission period is configured in MN and SN. Therefore, the latency in the MN for uplink data transmission may be substantially the same as that in the SN. The CN may perform uniform control over the RAN nodes it serves.

[0289] The MN or SN may notify the UE or CN of the response to the permissionless transmission configuration request that the UE or CN notified the MN or SN. The MN or SN may include in the response the ID of the node that is requested to configure the transfer without permission to notify the response. The MN or SN may associate the node that is requested to configure the transfer without permission with the response to the request to configure the transfer without permission in the node to notify them.

[0290] In response to the request to configure the non-grant transmission, the MN or SN may notify the target UE whether the non-grant transmission is configured. The MN and SN may report an acknowledgment (Ack) or a rejection (rejection). The MN or SN may notify information for identifying the target UE. The MN or SN may associate the response to the request to configure the transfer without permission with information for identifying the UE to notify them.

[0291] The above method can be applied to a response to a request to configure a transfer without permission between an MN and an SN. Upon receiving the response to the request to configure transmission without grant, the node must notify the UE or CN of the response to the request to configure transmission without grant according to the response. This can create the same benefits.

[0292] The methods disclosed in the first modification of the first embodiment can be applied to a radio channel type using SCG. In other words, the methods disclosed in the first modification of the first embodiment can be applied not only to the split radio bearer MCG and the split radio bearer SCG, but also to the radio bearer SCG. The SN may transmit without authorization using the SCG radio bearer. The methods disclosed in the first modification of the first embodiment can be appropriately applied to multiple connectivity (MC). Two or more SNs must be used. When the UE connects to one MN and two or more SNs, the grantless transmission may be configured using one or two or more SNs within the SNs to be connected.

[0293] The methods disclosed in the first modification of the first embodiment allow the SN to perform transmission without permission when the DC or MC is configured. Allowing the SN to perform a grantless transmission can eliminate the need for the SN to receive an SR and transmit an uplink grant in response to the SR, and reduce the waiting time for the SN to transmit uplink data.

[0294] Unauthorized transmission is performed in carrier aggregation (CA). Unauthorized transmission can be configured at CA. In other words, unauthorized transmission is supported under CA. Ungranted transmission may be supported in one or more cells (CCs) of a CA.

[0295] The SR is transmitted when the CA is in a predetermined cell. For example, the SR is sent in PCell, PUCCH SCell or SPCell. The cell in which the unauthorized transmission is configured need not be the cell in which the SR can be transmitted. The cell in which the uplink data is transmitted must be configured to transmit without permission. Since the cell in which the non-grant transmission is configured is not limited to, for example, the cell in which the SR can be transmitted, the non-grant transmission can be configured in a cell with a UE-friendly radio environment. The UE may perform non-granted transmission in a cell with a favorable radio environment, which may result in low latency performance and higher throughput in uplink communication.

[0296] The MN notifies the UE of the permissive transmission configuration for one or more cells. The MN must notify the unauthorized transmission configuration on a per-node basis (MN and SN) per cell. The MN needs to notify information for cell identification and configuration information for unauthorized transmission. The MN needs to obtain configuration information in advance for unauthorized transmission regarding the SN for each cell. The method disclosed as a method for configuring a DC permissive transmission must be applied to a receiving method.

[0297] Each node may notify the UE of the permissionless transmission configuration for one or more cells. The MN must notify the unauthorized transmission configuration regarding its own node for each cell. The SN must notify the unauthorized transmission configuration regarding its own node for each cell.

[0298] The MN or each node must notify the UE of the RRC configuration of the per-cell non-permission transmission via RRC signaling. Each cell needs to notify the UE of the L1 configuration of transmission without cell permission via L1 signaling. The cell must include the L1 configuration in the DCI to notify the configuration.

[0299] The cell may notify the UE of the L1 configuration for transmission without permission for different one or more cells. The cell must include in the DCI information for identifying a cell in which the non-granted transmission is configured and an L1 configuration for the non-granted transmission to notify the information and the configuration. Therefore, the UE need not always receive the control channels of all cells, but only need to receive the control channel of a particular cell. The power consumption of the UE can be reduced.

[0300] Regarding the CA, the MAC in each node schedules a cell that performs the CA. Thus, even when a cell notifies the L1 configuration to another cell, the radio resource configuration for unauthorized transmission of the other cell or activation/deactivation of unauthorized transmission can be timely reflected. This can increase the efficiency of using radio resources.

[0301] The UE may determine in which cell of the cells configured for non-granted transmission data is to be transmitted. When the L1 configuration is used, the UE may select a cell on which data is to be transmitted from among the activated cells. For example, the UE may measure the downlink path loss of each cell and determine that the uplink data should be transmitted in the cell with the least path loss.

[0302] The node can determine in which cell of the cells in which the transmission without permission is configured, the data should be transmitted. Each node can determine in which cell the data is to be transmitted. Only certain cells notify the UE of the activation with the L1 configuration. A certain cell notifies other cells of the deactivation using the L1 configuration. This allows the node to determine in which cell the UE is transmitting uplink data. For example, the node may receive from the UE an uplink sounding signal addressed to each cell, measure the uplink communication quality of the cell, and determine the uplink data transmission in the cell with the best uplink communication quality.

[0303] Information for identifying a cell to which uplink data is transmitted may be provided. The node may include information in the RRC configuration to notify the information via RRC signaling. Alternatively, the node may include information in the MAC CE to notify the information via MAC signaling. Unauthorized transmission can be dynamically configured. Moreover, the use of HARQ can reduce reception errors. Alternatively, the node may include in the L1 configuration information for identifying a cell in which uplink data is transmitted to notify the information via L1 signaling. Unauthorized transmission can be dynamically configured. Ungranted transmission can be immediately configured for a UE that does not perform HARQ.

[0304] Many cells may share part or all of the transmission without permission. All cells may have a transmission configuration without permission as a common configuration. For example, resource timings for unauthorized transmission are made different between multiple cells. Therefore, communication for transmission of uplink data can be started in a cell in which resources are available for transmission without grant, in the shortest period of time from the time reference in which the uplink data appears in the UE. The latency in uplink communication can be further reduced.

[0305] Therefore, unauthorized transmission is possible with a CA in one or more cells. For example, the UE may start communication for data transmission in a cell with a favorable radio propagation environment. Moreover, the uplink communication can be started not only in the cell in which the SR can be transmitted, but also in other cells.

[0306] Second embodiment

Configuring permissive transmission in uplink communications for a communication service requiring low latency may result in low latency performance. However, only configuring transmission without permission cannot fulfill the requirements of a communication service requiring not only a low latency performance but also a high reliability performance such as a URLLC service.

[0307] The solution to the problem is disclosed below.

[0308] Permissionless transmission can be configured in packet duplication, in which a packet is duplicated and identical packets are transmitted by the DC. Unauthorized transmission can be configured in the MN during packet duplication setup. Unauthorized transmission can also be configured in the SN during packet duplication setup. Alternatively, unauthorized transmission may be configured in one of the MNs and SNs at the time of packet duplication setup. "During installation of duplicate packages" may include the time during which the installation of duplicate packages is processed.

[0309] Packet duplication may be configurable in uplink communication in which non-granted transmission has been configured. When duplication of packets is performed in the uplink communication in which the non-granted transmission has been configured, the non-granted transmission may also be configured in the SN. As such, configuring both packet duplication and unauthorized transmission can improve not only low latency performance but also reliability.

[0310] When duplicating packets with a DC, packet duplication is configured between the MN and the UE. Here, the SN does not need to recognize the packet duplication configuration. The SN only needs to perform the same processes as the normal processes for transmitting and receiving packet data. As previously described, the RRC configuration is necessary to configure the transmission without permission. Thus, when attempting to configure non-permission transmission when duplicating packets using a DC, the SN cannot recognize whether it is necessary to configure the non-permission transmission and has a problem that it is unable to configure the non-permission transmission.

[0311] The solution to the problem is disclosed below.

[0312] The MN requests the SN to configure the transmission without permission. The MN asks the SN to configure the transfer without permission during the setting of packet duplication. The SN notifies the MN of the configuration for transmission without authorization. The MN notifies the UE of the unauthorized transmission configuration that has been configured in its own node and the configuration of the SN for unauthorized transmission. The methods disclosed in the first modification of the first embodiment should be properly applied to a method for an MN to request an SN to configure an unauthorized transmission and a method for configuring an unauthorized transmission between the MN, the SN, and the UE.

[0313] For example, a method may be applied to the MN to issue an instruction to the SN to configure the transfer without permission, instead of requesting the MN to the SN to configure the transfer without permission.

[0314] This allows the SN to recognize whether it is necessary to configure the transmission without permission, and configure the transmission without permission. Thus, unauthorized transmission can be configured by duplicating packets with DCs. This results in low latency performance and high reliability performance.

[0315] The MN may request the SN to create resource timings for unresolved transmission matching each other. The timing of the resources for the non-grant transmission may be indicated by a period or offset of the resources for the non-grant transmission. The MN may notify the SN of these parameters among the parameters for configuring an unauthorized transmission at its own node. SN can configure parameters.

[0316] Because this can make the transmission timings from the UE to both nodes coincide with each other, the latency caused by different transmission timings to the nodes can be reduced.

[0317] The MN may request the SN to create non-granted resource timings different from each other. The MN may configure, with different values, the timing parameters among the parameters for configuring the unauthorized transmission in its own node, and notify the SN of the configured values. SN can configure parameters.

[0318] When the transmission timings to the nodes are the same, the transmission power of the UE must be allocated to the nodes, and the transmission power to the nodes can be reduced. Thus, making transmission timings to nodes different from each other can prevent a reduction in uplink transmission power from the UE to the nodes.

[0319] The MN may request the SN to create ad hoc resource timings different from each other within a predetermined domain. The MN may configure, with different values within the predetermined domain, the timing parameters among the parameters to configure unauthorized transmission in its own node, and notify the configured values to the SN. SN can configure parameters.

[0320] This can prevent the decrease in uplink transmission power to the nodes and reduce latency by keeping transmission timings to the nodes within a predetermined domain.

[0321] When the MN tries to configure the duplication of packets in the uplink communication in which the transmission without permission has been configured, the SN cannot recognize whether it is necessary to configure the transmission without permission and has a problem that it is unable to configure the transmission without permission. permissions.

[0322] The solution to the problem is disclosed below.

[0323] The MN notifies the UE of configuring the duplication of packets with the DC in the uplink communication in which the non-grant transmission has been configured. In addition, the MN requests the SN to configure the transfer without authorization. The MN may notify the SN of the transmission configuration instruction without permission. The SN notifies the MN of the configuration for transmission without authorization. The MN notifies the UE of the unauthorized transmission configuration that has been configured in its own node and the configuration of the SN for unauthorized transmission. The methods disclosed in the first modification of the first embodiment should be properly applied to a method for configuring an unauthorized transmission between an MN, an SN, and a UE, such as a request to configure an unauthorized transmission from an MN to an SN.

[0324] Therefore, the SN can recognize whether it is necessary to configure the transmission without permission, and configure the transmission without permission. Thus, duplication of packets may be configured in the uplink communication in which transmission without permission in the MN has been configured. This results in low latency performance and high reliability performance.

[0325] FIG. 24 through 26 illustrate an exemplary sequence for configuring a transmission without permission when duplicating packets. Fig. 24 to 26 are connected via boundary locations BL2425 and BL2526. In Step ST1701, the MgNB determines to perform split-radio uplink packet duplication for the UE. In Step ST1702, the MgNB performs a DC setup process using a split radio bearer with the UE and the SgNB. In Step ST1703, the MgNB notifies the UE of the uplink packet duplication configuration. The MgNB shall perform notification via RRC signaling. In Step ST1704, the MgNB notifies the UE of activating duplication of packets. The MgNB shall perform notification via MAC signaling.

[0326] Upon receipt of activation of duplicating packets in Step ST1704, the UE starts duplicating packets in Step ST1705. The UE that started duplicating packets duplicates the uplink data and transmits the uplink data to the MgNB and SgNB. The UE transmits uplink data to the MgNB in Steps ST1706 to ST1708, and transmits uplink data to the SgNB in Steps ST1709 to ST1711.

[0327] In Step ST1712, the SgNB transmits to the MgNB the uplink data received from the UE. The SgNB may transmit uplink data via the S1 interface or the Xn interface. In Step ST1713, the MgNB compares the uplink data received by the MgNB with the uplink data received from the SgNB and removes redundant uplink data. Thus, duplication of uplink packets is performed using a split radio channel for MgNB and SgNB.

[0328] In Step ST1714, the MgNB determines the configurations of the MgNB and SgNB for transmission without permission. The determination method disclosed in FIG. 16 and 17 must be applied to this method of determination. When the unauthorized transmission is configured for uplink data for which packet duplication is performed, the MgNB may configure both the MgNB and the SgNB for unauthorized transmission. In Step ST1715, the MgNB notifies the SgNB of the instruction to configure the transmission without authorization. The MgNB may notify the SgNB of information to identify the target UE. The MgNB may notify the SgNB of some or all of the configuration to pass without authorization.

[0329] The MgNB may notify the SgNB of the period and offset of the resources for the unauthorized transmission as the configuration information for the unauthorized transmission. The combination of periods and resource offsets for the SgNB and MgNB for unauthorized transmission can mitigate the latency increase caused by the different resource timings of the SgNB and MgNB.

[0330] Upon receiving an instruction to configure transmission without permission from the MgNB, the SgNB configures transmission without permission in Step ST1716. Upon receiving an instruction from the MgNB, the SgNB needs to configure the non-grant transmission for the target UE that has priority over other UEs, although the configuration for the non-grant transmission includes saving radio resources. In Step ST1717, the SgNB notifies the response to the transmission configuration instruction without permission from the MgNB. Here SgNB notifies Ack. The SgNb notifies both the target UE identification information and the configuration for unauthorized transmission to the SgNB. In Step ST1718, the MgNB notifies the UE of the unauthorized transmission configuration in its own node and the unauthorized transmission configuration in the SgNB.

[0331] In Step ST1719, the UE configures non-grant transmission for the MgNB and SgNB. In Steps ST1720 to ST1722, the UE performs an ungranted transmission to the MgNB. In Steps ST1723 to ST1725, the UE performs an ungranted transmission to the SgNB. In Step ST1726, the SgNB transmits the uplink data received from the UE to the MgNB. In Step ST1727, the MgNB removes redundant uplink data.

[0332] Although the MgNB notifies the SgNB of the instruction to configure the transfer without permission, the MgNB may notify the SgNB of the request to configure the transfer without permission. Although the SgNB notifies the MgNB of the Ack, the SgNB may notify the MgNB of the rejection. For example, upon receiving a request to configure the transfer without grant, when the SgNB cannot configure the transfer without grant due to a lack of resources in its own node, the SgNB notifies the MgNB of the rejection. The SgNB may notify the lack of resources as cause information.

[0333] Upon receipt of the reject notification, the MgNB may, for example, determine the configuration of the unauthorized transmission only in its own node, and notify the UE of the MgNB-only configuration for the unauthorized transmission.

[0334] The MgNB may determine to re-request the SgNB to configure the transfer without permission, and notify the SgNB of the request to configure the transfer without permission. When the resource shortage is resolved, the SgNB includes the configuration to pass without permission in the Ack to notify the MgNB of the configuration. The MgNB may notify the UE of the MgNB and SgNB configurations for unauthorized transmission. When there is no change in the MgNB's configuration for unauthorized transmission, the MgNB can only notify the SgNB's configuration for unauthorized transmission.

[0335] Therefore, unauthorized transmission can be performed by duplicating uplink packets with the split radio channel of MgNB and SgNB. Thus, a lower latency can be achieved also during the execution of packet duplication. This can result in high reliability and low latency performance.

[0336] Duplication of uplink packages can be configured during DC setup. For example, the MN may include uplink packet duplication configuration information in an RRC connection reconfiguration message that the MN needs to notify the UE to notify the information. Upon receiving the RRC connection reconfiguration message in the DC setup process, the UE configures uplink packet duplication along with the DC setup. This may reduce the amount of RRC signaling.

[0337] FIG. 27 to 29 illustrate an exemplary sequence for configuring duplication of packets in an uplink communication in which an ungranted transmission has been configured. Fig. 27 to 29 are connected via boundary locations BL2728 and BL2829. Because the sequence illustrated in FIG. 27 to 29 includes exactly the same steps as those of the sequence illustrated in FIG. 24 to 26, the same step numbers are assigned to the same Steps and their general description is omitted.

[0338] In Step ST1801, the MgNB notifies the UE of the configuration of the MgNB to transmit without permission. In Step ST1802, the UE configures a grantless transmission for the MgNB. When uplink data appears at the UE, the UE and the MgNB perform an ungranted transmission in Steps ST1803 to ST1805.

[0339] In Step ST1806, the MgNB determines to perform duplication of packets using a split radio channel. In Step ST1714, the MgNB determines the configurations of the MgNB and the SgNB to transmit without permission. The MgNB that has determined to perform packet duplication with the split radio channel in Step ST1806 performs the DC setup process with the UE and the SgNB in Step ST1807. After executing the DC setting process in Step ST1807, the MgNB notifies the SgNB of the instruction for configuring the transfer without authorization in the SgNB in Step ST1715.

[0340] In Steps ST1716 to ST1719, the MgNB and SgNB configure transmission without permission for the UE. The MgNB may change the transmission configuration without permission and notify the UE of the changed configuration for transmission without permission in Step ST1718. The MgNB that notified the configurations of the MgNB and the SgNB for unauthorized transmission in Step ST1718 notifies the UE of the uplink packet duplication configuration in Step ST1808. The MgNB shall perform notification via RRC signaling. In Step ST1809, the MgNB notifies the UE of activating duplication of packets. The MgNB shall perform notification via MAC signaling.

[0341] Upon receiving the activation of duplicate packets from the MgNB in Step ST1809, the UE starts to duplicate uplink data in Step ST1810. When uplink data appears at the UE, the UE performs packet duplication on the uplink data. The UE and the MgNB perform an unauthorized transmission in Steps ST1720 to ST1722, and the UE and the SgNB perform an unauthorized transmission in Steps ST1723 to ST1725.

[0342] This may configure duplication of packets in uplink communications configured to transmit without permission. Thus, in uplink communication that results in low latency performance through non-granted transmission, performing packet duplication can lead to higher reliability. This can result in low latency and high reliability performance.

[0343] Unauthorized transmission may be configured during the DC setup process. For example, the MN may include a request to configure a transfer without permission or an instruction to configure a transfer without permission in an Xn/X2 message that the MN needs to notify the SN, such as an SgNB Modify Request message to notify the request or instruction. For example, the SN may include configuration information for unauthorized transmission in an Xn/X2 message that the SN must notify the MN, such as an SgNB Modify Request acknowledgment message, to notify the information. This method can be applied to the method disclosed in the first modification of the first embodiment. This can reduce the amount of Xn/X2 signaling.

[0344] For example, the MN may include configuration information for unauthorized transmission in the RRC connection reconfiguration message that the MN needs to notify the UE to notify the information. Upon receiving the RRC connection reconfiguration message in the DC setup process, the UE configures the non-grant transmission along with the DC setup. This method can be applied to the method disclosed in the first modification of the first embodiment. This may reduce the amount of RRC signaling.

[0345] Uplink packet duplication may be configured during DC setup. For example, the MN may include uplink packet duplication configuration information in an RRC connection reconfiguration message that the MN needs to notify the UE to notify the information. Upon receiving the RRC connection reconfiguration message in the DC setup process, the UE configures uplink packet duplication along with the DC setup. This may reduce the amount of RRC signaling.

[0346] Duplication of uplink packets can be configured in the process of configuring transmission without permission. For example, the MN may include uplink packet duplication configuration information in the RRC signaling to configure the unauthorized transmission that the MN needs to notify the UE to notify the information. Upon receiving the RRC signaling to configure the non-grant transmission, the UE configures duplication of uplink packets along with the configuration of the non-grant transmission. This may reduce the amount of RRC signaling.

[0347] Whether to activate or deactivate the configuration for non-grant transmission when configuring the non-grant transmission can be done via MAC signaling. Activation/deactivation information of each node may be provided to configure transmission without permission. The information may be included in the MAC CE. The MN notifies the UE whether to enable or disable the configuration for unauthorized transmission with the MAC CE. The SN may notify the UE whether to enable or disable the configuration for unauthorized transmission with the MAC CE.

[0348] Upon receiving the activation/deactivation information of each node to configure the non-grant transmission, the UE configures the non-grant transmission for the node. Providing per-node activation/deactivation information for configuring the non-grant transmission in MAC signaling can dynamically and timely configure the non-grant transmission for the UE. This can reduce wasteful use of radio resources.

[0349] Activation/deactivation of duplicate packets is configured via MAC signaling. With the inclusion of a MAC CE indicating activation/deactivation information for configuring unauthorized transmission in each node, the information can be notified in MAC signaling including a MAC CE for configuring duplication activation/deactivation. Notification via the same MAC signaling can reduce the amount of signaling.

[0350] FIG. 30 and 31 illustrate an exemplary sequence for notifying duplication activation of packets and activating configuration for unauthorized transmission over the same signaling, and performing duplication of packets and configuration of unauthorized transmission. Fig. 30 and 31 are connected via boundary location BL3031. Because the sequence illustrated in FIG. 30 and 31 includes exactly the same steps as those of the sequence illustrated in FIG. 27 to 29, the same step numbers are assigned to the same Steps and their general description is omitted.

[0351] In Step ST1901, the MgNB determines to perform duplication of split radio bearer packets for the UE, and then determines the configurations of the MgNB and SgNB for transmission without permission. In Step ST1902, the MgNB performs a DC setup process with the UE and the SgNB. After executing the DC setting process in Step ST1902, the MgNB notifies the SgNB of the instruction for configuring the transfer without authorization in the SgNB in Step ST1715.

[0352] In Steps ST1716 to ST1718, the MgNB and SgNB configure transmission without permission for the UE. The MgNB that notified the configuration of the MgNB and the SgNB for unauthorized transmission in Step ST1718 notifies the UE of the uplink packet duplication configuration in Step ST1808. In Step ST1903, the MgNB notifies the UE of activating duplication of packets and activating the configurations of the MgNB and the SgNB for unauthorized transmission over the same signaling. The MgNB shall notify via MAC signaling.

[0353] For example, the MgNB includes, in the same MAC PDU, a MAC CE including enabling duplication of packets, and a MAC CE including activating configurations on the MgNB and SgNB for permissive transmission to notify the MAC CE. Upon receiving the activation of duplication of packets and the activation of configurations of the MgNB and SgNB for permissive transmission in Step ST1903, the UE configures permissive transmission for the MgNB and SgNB and starts duplication of packets in Step ST1904.

[0354] When uplink data appears at the UE, the UE performs packet duplication on the uplink data. The UE and the MgNB perform an unauthorized transmission in Steps ST1720 to ST1722, and the UE and the SgNB perform an unauthorized transmission in Steps ST1723 to ST1725.

[0355] This can lead to performance with lower latency and high reliability. When the MgNB intends to start or stop transmission without permission for the UE, activation/deactivation of the configuration for transmission without permission by the MAC CE provides dynamic control. This can increase the efficiency of using radio resources. Notification of activation/deactivation of duplication of packets and activation/deactivation of a configuration for transmission without permission through the same MAC signaling can reduce the amount of signaling.

[0356] Permissionless transmission can be configured in packet duplication, where packets are duplicated and identical packets are transmitted by the CA. Permissionless transmission may be configured in the cell in which packet duplication is to be performed at the time of packet duplication setup. "During installation of duplicate packages" may include the time during which the installation of duplicate packages is processed.

[0357] Packet duplication (CA) may be configured in uplink communication configured for non-granted transmission. When packet duplication is performed in the uplink communication in which the non-granted transmission is configured, the non-granted transmission may be configured in the cell in which the packet duplication is to be performed.

[0358] The node notifies the UE of the unauthorized transmission configuration that has been configured in the cell in which packet duplication is to be performed. The disclosed method for creating a permissionless transmission that can be configured to duplicate packets with a DC should be properly applied to this notification method.

[0359] Therefore, transmission without permission when duplicating packets (CA) can be configured. Packet Duplicating (CA) may be configured in an uplink communication that has been configured to transmit without permission. This can result in low latency and high reliability performance. Moreover, low latency performance and high reliability can be achieved using a single node.

[0360] Third embodiment

In an uplink preemptive transmission (see Non-Patent Document 14 (R1-1712747)), a UE that performs a preemptive transmission transmits an SR to a gNB. A UE that performs a preemptive transmission may be, for example, a UE that performs URLLC communication. The gNB notifies the UE to be preempted of the information indicating that preemption communication will take place. The notification information may include information about frequency resources to be used for preemptive transmission. The notification information may include time resource information. The notification information may include power resource information. The UE to be preempted may be, for example, a UE that is communicating with eMBB.

[0361] The gNB may be configured to receive information indicating that preemptive communications will be performed for all or part of the UEs it serves. The UE may start receiving information indicating that preemptive communication will be performed with a configuration. The UE to be preempted may be a configured UE. The same may be true for the following description.

[0362] In response to the notification, the UE to be preempted may reduce the uplink transmission power with frequency and/or time resources to perform preemption transmission. Alternatively, the UE to be preempted may suppress the uplink transmit power with the resources. This can improve reliability in relation to preemption.

[0363] The UE to be preempted does not need to transmit uplink data scheduled for transmission with frequency and/or time resources to perform preemption transmission. This may reduce the amount of processing in that UE and gNB. As an alternative example, the UE may transmit uplink data using resources other than the above resources. For example, the UE may delay uplink data beyond the time resources to perform a preemptive transmission to transmit uplink data. The UE may stop transmitting uplink data that cannot be completely transmitted in response to a scheduling grant prescribed by the gNB. Whether or not the UE transmits uplink data and/or transmits uplink data with resources other than the resources can be determined according to the decoding performance of the gNB. Increasing the HARQ decoding performance in uplink transmission can improve uplink communication reliability of the UE to be preempted.

[0364] As an alternative example, the UE to be evicted may re-execute the coding and modulation processes. The replay may be applied, for example, to uplink data to be transmitted with temporary resources after preemptive transmission. For example, the encoding speed can be increased by repeated execution. The method for re-performing the coding and modulation processes in preemptive transmission (eg, the coding rate or the data to be re-encoded) may be predefined in the standard. The UE to be preempted may notify the base station of the method information. The UE may send notification via, for example, L1/L2 uplink signaling or MAC signaling. This can, for example, prevent loss of transmission of uplink data from a UE to be preempted due to preemption transmission.

[0365] The gNB notifies the UE that performs the preemptive transmission (may be referred to as the preemptive UE hereinafter) of the uplink permission. The UE that performs the preemptive transmission performs the uplink preemption transmission with the grant.

[0366] The application of the method creates the following problem. In particular, since a UE that performs a preemptive transmission needs to transmit an SR to the gNB after the occurrence of data that is subject to an uplink transmission, it takes some time to actually perform the preemptive transmission. This causes a problem of not being able to guarantee low latency in uplink preemption transmission.

[0367] As a solution to the problem, a UE that performs a preemptive transmission may notify a UE to be preempted (may be referred to as a preempted UE hereinafter) of information indicating that preemptive communication will be performed. The notification information may include information about frequency resources to be used for preemptive transmission. The notification information may include time resource information. The notification information may include power resource information. The UE to be preempted does not need to transmit uplink data that is scheduled to be transmitted with the frequency and/or time resources to perform the preemption transmission. This allows a UE that performs a preemptive transmission to quickly perform a preemptive transmission.

[0368] The application of the method creates the following problem. In particular, when the UE that performs the preemptive transmission is far away from the UE to be preempted, the UE to be preempted may not be able to accurately receive the information notification. As a result, the UE to be preempted transmits uplink data with the timing of the preemption transmission, which interferes with the preemption transmission. Moreover, the gNB cannot understand the timing of the preemptive transmission and may not be able to accurately receive a signal indicative of the preemptive transmission. This causes the problem of decreasing reliability in connection with preemption.

[0369] The solution to the problem is disclosed below.

[0370] The gNB performs a preemption indication for the UE to be preempted. The notification may indicate the timing at which the preemptive transmission may occur. In other words, preemptive transmission may or may not actually occur with a timing. The number of timestamps indicated by one of the notifications may be one or more.

[0371] The frequency resources to be used to transmit the preemption indication from the gNB may be in an area different from that to be used to receive downlink user data from the UE to be preempted. For example, frequency resources may be provided to indicate preemption. This allows, for example, a UE to be preempted to easily understand the occurrence of preemption.

[0372] The gNB may broadcast, to the UEs it serves, information about the frequency resources that should be used to transmit the preemption indication. The UEs that are served by the gNB may include the UE to be preempted. As an alternative example, the gNB may notify the UEs it serves in a dedicated manner of frequency resource information. gNB can implement dedicated notifications via dedicated RRC signaling. For example, frequency resource information may be included in signaling for RRC Connection Reconfiguration (RRCConnectionReconfiguration) from the gNB to the UEs it serves.

[0373] As an alternative example of frequency resources, frequency resources may be in the same area as those to be used to receive downlink user data from the UE to be preempted. For example, a PDCCH may be used. The gNB may include in the PDCCH information about the set of timings in which preemption communication may occur. This can save frequency resources in the communication system. The PDCCH may be dedicated to the UE PDCCH. This provides flexible resource management for each UE. A PDCCH common to multiple UEs, such as a common PDCCH group, may be used. This may reduce the amount of signaling required to indicate the preemption.

[0374] The gNB may encode and/or modulate a preemption indication with information about the UE to be preempted. For example, the gNB may encode and/or modulate a preemption indication with the C-RNTI of the UE to be preempted. The UE to be preempted may receive a preemption indication with information. This may, for example, prevent other UEs from erroneously receiving a wipe indication, which may therefore prevent the communication system from degrading.

[0375] Encryption of the CRC code, eg, encryption of the CRC code with all or part of the C-RNTI, may be used as an example of coding and/or modulation of the preemption indication. Encryption may be, for example, an XOR operation on the CRC bits of the code and the C-RNTI. As an alternative example, encryption of a bit of information indicating a wipe indication with all or part of the C-RNTI may be used. As an alternative example, the CRC code may be extracted using a bit string obtained by concatenating a bit of information indicating a wipe indication with all or part of the C-RNTI. The bit string can be used for other encoding processes.

[0376] As an alternative example, information about the UE to be preempted may be used for modulation. For example, the sequence information for the DMRS associated with the preemption indication may be determined using information about the UE to be preempted. The sequence information may be, for example, a Zadoff-Chu root index (ZC), a cyclic shift amount (may be referred to as CS hereinafter), or a combination of the two. For example, the root index in the ZC code and the amount of cyclic shift may be determined using the C-RNTI. As an alternative example, the sequence information may be an encryption identifier. This may, for example, reduce the amount of processing in UEs other than the UE that must be preempted.

[0377] As an alternative example, the constellation value of each RE after the preemption information is modulated can be changed using information about the UE to be preempted. For example, a predetermined number of C-RNTI bits may be extracted from the beginning and converted to constellation values. Operations can then be performed on the received constellation values with the constellation value of the first RE after the preemption information is modulated, and the results can be used for transmission. A predetermined number of C-RNTI bits may be extracted from the bit following the extracted bits and converted to constellation values. Operations can then be performed on the obtained constellation values using the constellation value of the second RE after the preemption information is modulated. From now on, the operation on the constellation value of each RE after the preemption information is modulated with the C-RNTI can be performed in a similar manner. Operations can be, for example, multiplication of complex numbers. In complex multiplication, the complex conjugate may be used for the constellation value of each RE, after the preemption information is modulated, and/or the constellation value converted from the C-RNTI. Operations can, for example, reduce the amount of computation in the modulation process.

[0378] The following items (1) to (6) are disclosed as pieces of information included in the indication of preemption to be transmitted from the gNB to the UE to be preempted.

[0379] (1) Frequency resources to be used for preemptive transmission

[0380] (2) Temporary resources to be used for preemptive transmission

[0381] (3) Presence or absence of uplink transmission of the UE to be preempted

[0382] (4) Uplink transmit power of the UE to be preempted

[0383] (5) Information about frequency/time resources to be used for transmission of uplink data that overlap with those of preemptive transmission; Three specific examples from (5-1) to (5-3) are listed below for information:

[0384] (5-1) no transmission

[0385] (5-2) a transmission overlapping a preemptive transmission; And

[0386] (5-3) transmission with frequency/time resources different from those for preemptive transmission.

[0387] (6) Combinations (1) to (5) above.

[0388] Item (1) may be configured, for example, based on RB. This allows, for example, a UE to be preempted to transmit uplink data using different frequency resources than those to be used for preemption transmission.

[0389] Item (2) may be configured, for example, per symbol. The character unit may be the character unit in the UE to be preempted. This allows, for example, a UE to be preempted to transmit uplink data in a symbol other than that to be used for preemption transmission.

[0390] In item (3), for example, an uplink transmission of a UE to be preempted need not be performed. Interference with preemption communication can be reduced. This can, for example, improve the reliability of preemptive communication. As an alternative example, an uplink transmission may be performed at a UE that is to be preempted. This, for example, facilitates uplink transmission control at the UE to be preempted.

[0391] Item (4) may be, for example, directly an uplink transmission power value or a value indicating a difference between uplink transmission powers. Therefore, for example, reducing the uplink transmission power of the UE to be preempted with the timing of the preemption transmission can ensure the reliability of the preemption transmission.

[0392] In clause (5-1), the UE to be preempted does not need to transmit uplink data that overlaps those in the preemptive transmission. For example, this UE may mask uplink data that overlaps those in the preemptive transmission. This can facilitate the processes in the gNB and UE and ensure the reliability of the preemptive transmission.

[0393] In clause (5-2), the UE to be preempted may transmit uplink data that overlaps those in the preemption transmission with frequency/time resources in the preemption transmission. This further facilitates processes in gNB and UE.

[0394] In clause (5-3), the UE to be preempted may reallocate uplink data that overlaps those in preemptive transmission to different frequency/time resources from those in preemptive transmission, to transmit uplink data. Information about frequency/time resources to be used for re-allocation may be included in (5-3). Time resources for preemptive transmission may use different frequency resources than those in preemptive transmission. Alternatively, frequency/time resources that are later than the time resources for preemptive transmission may be used. Since this can, for example, ensure continuity of uplink transmission data of a UE to be preempted, then, for example, HARQ decoding efficiency in a gNB can be improved.

[0395] As an alternative example, in clause (5-3), the UE to be evicted may re-execute the coding and modulation processes. The replay may be applied, for example, to uplink data to be transmitted with temporary resources after preemptive transmission. For example, the encoding speed can be increased by repeated execution. The manner in which the coding and modulation processes are re-executed in preemptive transmission (eg, the coding rate or the data to be re-encoded) may be predefined in the standard. The UE to be preempted may notify the base station of the method information. The UE may send notification via, for example, L1/L2 uplink signaling or MAC signaling. This can, for example, prevent transmission loss of uplink data from a UE to be preempted due to preemption transmission.

[0396] The gNB may include preemption activation/deactivation information in the preemption indication. The timing for activating the preemptive transmission may be determined, for example, by further selecting whether a transmission is possible from among the transmission timings at which pre-emption communication can be performed. The preempted UE may determine whether or not there is a preemption association using the information. Instead of activation/deactivation information, only activation information can be used. The preempted UE may determine that the preemptive transmission is deactivated by the lack of activation information. This allows, for example, the preempted UE to reserve many temporary resources with which uplink transmission is possible.

[0397] The gNB may broadcast and/or notify the preemption indication to UEs that can be preempted. The UEs that can be preempted may be all or part of the UEs that are being served by the cell. In the following third embodiment, the notification from the gNB to the UE being preempted may be a broadcast and/or notification to the UE that can be preempted.

[0398] The broadcast information can be used as a preemption indication for all UEs served by the cell. Alternatively, a notification similar to the notification for the preempted UE can be used. The notification may be encoded and/or modulated, eg using RNTI for system information. Alternatively, the notification may be encoded and/or modulated, eg using a common identifier in the base station beam to be used by the UE, eg beam identifier. The UE in the cell may be notified using the RNTI. Therefore, for example, a wipe indication can be sent to multiple UEs with less signaling.

[0399] A notification similar to the notification for the preempted UE may be used as a preemption indication for a portion of the UEs served by the cell. The notification may be encoded and/or modulated using, instead of C-RNTI, for example, a group identifier (eg, group RNTI) to which the UE part belongs. Therefore, for example, a wipe indication can be sent to multiple UEs with less signaling. The group may be determined, for example, using a service to be used in a communication system (eg, eMBB) or through another method. For example, the group ID may be defined using the service ID.

[0400] As an alternative example, the gNB may notify the beam part UE of the preemption indication. The part of the beams may be, for example, a beam to be used by a UE that is performing preemptive communication, or a beam to be used by a UE that is to be preempted.

[0401] The UEs in the beam part may be, for example, all UEs in the beam. A notification similar to the notification for the preempted UE may be used as a preemption indication for all UEs in the beam. The notification may be encoded and/or modulated, eg using RNTI for system information instead of C-RNTI. Alternatively, the notification may be encoded and/or modulated, eg using a common beam identifier, eg a beam identifier. A new beam ID may be provided.

[0402] A UE in a beam part may be, for example, a part of a UE in a beam. A notification similar to the notification for the preempted UE may be used as a preemption indication for the part of the UE in the beam. The notification may be encoded and/or modulated using, instead of the C-RNTI, for example, a group identifier (eg, RNTI of the group) to which the UE part belongs. The group may be determined, for example, using a service to be used in a communication system (eg, eMBB) or through another method. For example, the group ID may be defined using the service ID.

[0403] The UE to be preempted receives the preemption indication. The UE may stop the uplink transmission as an uplink transmission operation that overrides the preemptive transmission. This can, for example, guarantee reliability in preemptive transmission. The UE does not need to transmit (eg, may mask) the uplink data scheduled for transmission in the section in which the uplink transmission was stopped. Alternatively, the UE may reallocate the uplink data scheduled for transmission in the section in which the uplink transmission was stopped to other frequency/time resources to transmit the uplink data. The example described in paragraph (5-3), which is disclosed as a piece of information included in the indication of preemption to be transmitted from the gNB to the UE to be preempted, can be applied to the redistribution method.

[0404] As an alternative example, the UE may perform an uplink transmission that overrides the preemptive transmission. The following items (1) to (4) are disclosed as examples of an uplink transmission that overrides a preemptive transmission:

[0405] (1) low power transmission;

[0406] (2) decimated frequency resource transmission;

[0407] (3) transmission with decimated time resources; And

[0408] Combinations (1) to (3) above.

[0409] Reducing the uplink transmission power that overlaps that of the preemptive transmission in (1) can, for example, ensure reliability in preemptive transmission.

[0410] In clause (2), the UE may thin out the frequency resources per RB or per RE to transmit the frequency resources. This creates the same benefits as those in, for example, paragraph (1).

[0411] In clause (3), the UE may puncture temporary resources, eg, per symbol, to transmit temporary resources. This creates the same benefits as those in, for example, paragraph (1).

[0412] In items (2) to (4), the UE to be evicted may re-execute the coding and modulation processes in the same way as in the example described in item (5-3), which is disclosed as a piece of information, included in the preemption indication to be passed from the gNB to the UE to be preempted. The example described in paragraph (5-3), which is disclosed as a piece of information included in the indication of preemption to be transmitted from the gNB to the UE to be preempted, can be applied to the reexecution method. This may, for example, prevent transmission loss of uplink data from a UE to be preempted due to preemption transmission.

[0413] One or more setup patterns may be provided in advance for uplink transmission operations that overlap the UE's preemptive transmission. Templates may be defined in the standard or defined by gNB. The gNB may broadcast or in a dedicated manner notify the UE of certain setup patterns. The gNB may notify via dedicated RRC signaling.

[0414] The gNB may include, in an indication of the preemption to be transmitted by the UE, identifiers indicating setup patterns. Therefore, for example, reducing the size of the wipe indication transmission may reduce the frequency resources that must be used to transmit the wipe indication.

[0415] As an alternative example, gNBs do not need to include identifiers indicating installation patterns in the preemption indication. For example, when the number of setup patterns is one, the gNB does not need to include an identifier indicating the setup pattern in the preemption indication. This may, for example, further reduce the frequency resources that must be used to transmit the wipe indication.

[0416] The gNB may notify the preemptive UE of the uplink permission. The gNB may transmit an uplink grant to this UE even if there is no SR from the UE.

[0417] The UE may perform preemptive transmission with an uplink grant. Alternatively, the UE does not need to perform a preemptive transmission. The UE does not need to perform preemptive transmission in the absence of uplink data to be preempted.

[0418] The preemption indication from the gNB to the preempted UE and the uplink grant from the gNB to the preemptive UE may be transmitted via the same signaling. For example, a PDCCH common to multiple UEs may be used as signaling. This may, for example, reduce the amount of signaling from the gNB to each UE.

[0419] As an alternative example, the preemption indication from the gNB to the preempted UE and the uplink grant from the gNB to the preemptive UE may be transmitted via different signaling. For example, the gNB may send an uplink grant before the wipe indication. This allows, for example, the preemptive UE to save time for coding and modulation processes after receiving an uplink grant.

[0420] The character lengths to be used in the wipe indication and uplink resolution may differ from each other. Alternatively, different TTIs may be used to indicate uplink preemption and enable. Therefore, for example, even when the preempting UE and the preempting UE use different symbol lengths and/or TTIs, the method described in the third embodiment can be applied.

[0421] The gNB may periodically send a preemption notification to the preempted UE. The period may be defined in the standard, or defined by the gNB, for its broadcast to the UEs it serves, or for its dedicated per-UE notification. The gNB may notify via dedicated RRC signaling. The uplink grant from the gNB to the preemptive UE may be processed in exactly the same manner as the preemption notification.

[0422] The notice of preemption may be an indication of preemption.

[0423] gNB can change the period. The gNB can change the period, for example, through dedicated RRC signaling. The modified period may be, for example, a radio frame, slot, mini-slot, symbol, or other unit of time. Therefore, for example, when the gNB prolongs the period, the frequency of receiving the preemption indication in the preempted UE decreases. As a result, the power consumption in the preempted UE can be reduced.

[0424] The gNB may aperiodically perform a preemption indication for the UE being preempted. The preempted UE may always perform the receive operation of the preemption indication with the frequency resources with which the preemption indication is transmitted, or may perform the reception operation with the transmission timing of the preemption indication that the gNB notifies in advance. The gNB may notify the timing of the preemption indication to the preempted UE, for example, via RRC signaling.

[0425] The preempted UE may monitor the PDCCH with respect to the preemptive UE as an alternative example when the gNB aperiodically performs a preemption indication for the preempted UE. The gNB may encode the PDCCH for the preemptive UE using a group ID from the UE, including the preemptive UE and the preempted UE. The group identifier may be, for example, a beam identifier, an RNTI for system information, or another identifier.

[0426] As an alternative example, the gNB may notify the preempted UE in advance of the preemptive UE's identity, such as C-RNTI. The group ID of the UEs that can perform preemptive communication may be used instead of the UE preemptive ID. The preemptive UE must belong to a group.

[0427] The preempted UE may obtain PDCCH information for the preemptive UE using a group ID from the UE including the preemptive UE and the preempted UE, a preemptive UE identifier such as the C-RNTI of the preemptive UE, or a group ID from the UE, which may communicate with displacement. The preempted UE may determine, using the information, the presence or absence of a preemptive transmission and the frequency/time resources to be used for the preemptive transmission. This, for example, eliminates the need for new frequency resources to indicate preemption, which therefore ensures efficient use of the communication system.

[0428] The gNB may semi-persistently execute the preemption indication to the UE being preempted. This may, for example, reduce the number of wipe indication transmissions from the gNB, which may therefore reduce power consumption in the gNB. The semi-persistent notification may include some or all of the information disclosed in the third embodiment as information included in the preemption indication for the UE being preempted. The semi-permanent notification may include a notification validity period, i. e. information indicating for which period the notification includes preemptive transmission information.

[0429] The gNB may send a semi-persistent notification using predefined frequency/time resources. The gNB may send a semi-persistent notification, eg, using broadcast information via dedicated RRC signaling, via MAC signaling, or via L1/L2 signaling. Alternatively, new frequency/time resources may be provided to transmit the semi-persistent notification. The gNB may notify the preempted UE of the resource information in advance.

[0430] The gNB may semi-statically execute the preemption indication for the UE being preempted. This may, for example, reduce the amount of signaling from the gNB to the preempted UE. The semi-static notification may include some or all of the pieces of information (1) through (6) disclosed as information included in the preemption indication to be transmitted from the gNB to the UE to be preempted as information included in the preemption indication. preemption indication for the UE being preempted. The gNB may send a semi-static notification, eg via broadcast information or via dedicated RRC signaling.

[0431] Can be combined in many ways. For example, the gNB may combine the semi-static preemption indication with the PDCCH preemption indication to notify the preempted UE of the combined preemption indication. For example, the gNB may include, in the semi-static preemption indication, information about the timing of the preemption transmission and frequency resources or information about the operations of the preempted UE upon the occurrence of the preemption transmission. The gNB may include preemption activation/deactivation information in the PDCCH preemption indication. The preempted UE may stop uplink transmission using the semi-static preemption indication and the PDCCH preemption indication, eg, with transmission timing to activate the preemption transmission. Therefore, for example, the gNB can perform the preemption indication for the preempted UE with less signaling.

[0432] As an alternative example, the gNB may include in the semi-static preemption indication information about the operations of the preempted UE upon the occurrence of a preemptive handover. The gNB may include preemption timing information and frequency resources in the PDCCH preemption indication. The preempted UE may stop uplink transmission using the semi-static preemption indication and the PDCCH preemption indication, eg, when timing the preemptive transmission. This provides, for example, flexible control over frequency/time resources in connection with preemption, in addition to the above-mentioned advantages.

[0433] As an alternative example, multi-method combinations, a gNB may use a semi-permanent preemption indication and a PDCCH preemption indication. The information included in the semi-permanent preemption hint may be identical to that in the semi-static preemption hint, or include information about the period of validity of the notification. This creates exactly the same benefits as previously described.

[0434] FIG. 32 illustrates an example in which the gNB performs uplink preemption (UL) indication for the preempted UE with a region in frequency resources other than that to be used for transmitting and receiving downlink user data to and from the preempted UE. Fig. 32 illustrates an example of FDM. Fig. 32 illustrates an example in which the preempted UE performs eMBB communication while the preemptive UE performs URLLC communication. Fig. 32 illustrates an example in which the timing with which preemptive transmission is possible occurs twice per slot.

[0435] In FIG. 32 gNB transmits uplink preemption instructions 4001 and 4002 to the preempted UE. The gNB may send uplink preemption indications using different frequency resources than those of the PDCCH 4003 and PDSCH 4004. The preempted UE stops eMBB uplink communication 4005 at the time reference 4006 indicated by the uplink preemption indication 4001. The preempted UE stops eMBB uplink communication 4005 also with the timing 4007 indicated by preemption indication 4002. The preemptive UE does not perform URLLC communication with timing 4006 and transmits URLLC communication 4008 with timing 4007.

[0436] FIG. 33 illustrates an example in which the eNB performs the uplink preemption indication for the preempted UE with the PDCCH. Fig. 33 illustrates an example of FDM. Fig. 33 illustrates an example in which the preempted UE performs eMBB communications while the preemptive UE performs URLLC communications. Fig. 33 illustrates an example in which a timing with which preemptive transmission is possible occurs twice per slot. On FIG. 33, the same numbers are assigned to signals overlapping with those in FIG. 32 and their general description is omitted.

[0437] An uplink preemption indication 4101 is transmitted to the preempted UE in the first symbol of the PDCCH 4003 in FIG. 33. The uplink preemption indication 4101 includes preemption timing information 4006 and 4007. The preempted UE receives an uplink preemption indication 4101 to obtain timing information 4006 and 4007. The preempted UE stops eMBB uplink transmission with timings 4006 and 4007.

[0438] Since FIG. 33 is identical to FIG. 32 in other aspects, its description is omitted.

[0439] Although the uplink wipe indication 4101 is transmitted in the first symbol of the PDCCH 4003 in FIG. 33, the first character need not be used. For example, the last character or the character in the middle may be used. An uplink preemption indication 4101 may occupy a portion of the frequency resources of the PDCCH 4003.

[0440] Although FIG. 33 illustrates an example of FDM, it can be applied to TDM. For example, an uplink preemption indication 4101 may be included in the PDCCH 4003 to be transmitted in TDM. The preemption communication timing indicated by uplink preemption indication 4101 may be included in the UL transmission timing in TDM. This also allows, for example, transmission of an uplink preemption indication from the base station to the preempted UE in TDM.

[0441] A gNB may provide a timing reference with which preemptive transmission is possible once or multiple times per slot. The gNB may focus on one or more timings to be allocated to multiple UEs that can perform preemptive transmission. This may, for example, reserve uplink transmission resources in the preempted UE even when there are many UEs that can perform preemptive transmission. Alternatively, the gNB may disperse across multiple timings a timing to be allocated to multiple UEs that can perform preemptive transmission. This may, for example, reduce the likelihood of collision on the timing of the preemptive transmission among the plurality of UEs that can perform the preemptive transmission.

[0442] A gNB may receive contention-based preemptive transmissions from multiple preemptive UEs. gNBs and preemptive UEs may perform the preemption retransmission process using HARQ feedback. This allows the gNB to consistently accept contention-based preemptions.

[0443] Another solution is disclosed. The gNB notifies the preemptive UE of the time resources and/or frequency resources with which preemption communication may occur. The notification may include information about the preemption association period. The notification may include information about the operations that overlap the preemptive transmission among the uplink transmission operations in this UE. The operation information may be, for example, information indicating stop of uplink transmission or pieces of information of items (1) to (4) disclosed as examples of uplink transmission that overlaps the preemptive transmission. The gNB may broadcast to the UEs that the gNB is serving, or in a dedicated manner notify the preempted UE. The gNB may implement dedicated notification via dedicated RRC signaling, eg signaling for RRC connection reconfiguration. In response to the notification, the preempted UE may stop the uplink transmission or perform the operations indicated in items (1) to (4), which are disclosed as examples of an uplink transmission that overrides the preemptive transmission. This, for example, eliminates the need for dynamic preemption indication for the preempted UE, which can lead to efficient use of frequency/time resources.

[0444] This solution is different from the solution using preemption indication by semi-static notification of preemptive transmission information for the preempted UE.

[0445] The gNB may send a notification to the preemptive UE. In other words, the gNB may notify the preemptive UE in advance of time resources and/or frequency resources with which preemption communication can be performed. This facilitates scheduling at the preemptive UE.

[0446] The gNB may notify the preemptive UE of the uplink permission. The information included in the uplink grant and the operations of the preemptive UE after receiving the uplink grant may be identical to those described for the solution using the preemption indication. Since this enables, for example, dynamic scheduling at the preemptive UE in accordance with the state of the radio link, reliability of preemptive communication can be guaranteed.

[0447] Another solution is disclosed. The gNB applies the grantless handover to the preemptive UE. In other words, the gNB notifies the preemptive UE of the time resources and/or frequency resources over which preemption communication can be performed. The notification may include information about the preemption association period. The notification may include uplink grant information for the preemptive UE. The gNB may broadcast a notification to the UEs that the gNB serves, or in a dedicated manner transmit the notification to the preemptive UE. Dedicated notification may be via dedicated RRC signaling, eg signaling for RRC connection reconfiguration.

[0448] A method for notifying the time resources and/or frequency resources by which preemption association may occur, which is indicated as a decision, can be applied to the notification from the gNB to the preempted UE and the operation of that UE. This may reduce the amount of signaling to notify from the gNB to the preempted UE.

[0449] Notification from the gNB to the preempted UE and broadcast and/or notification from the gNB to the preemptive UE may be performed via different signaling. As an alternative example, the same signaling may include both of the pieces of information. This can reduce the amount of signaling from the gNB to each UE.

[0450] As an alternative example of applying a non-granted transmission, the gNB may broadcast or notify the preemptive UE in advance of the transmission timing information with which to preemptively communicate and/or the transmission power information. The transmission timing may be information about a transmission period. The broadcast or notification of transmission timing information may be per mini-slot or per symbol. Broadcast or notification may be via RRC signaling.

[0451] The gNB may notify the preemptive UE of the preemptive transmission activation/deactivation information. The timing for activating a preemptive transmission may be determined, for example, by further selecting whether a transmission is possible among the timings with which preemption can be associated. Instead of activation/deactivation information, only activation information may be used. The preemptive UE may determine that the preemptive transmission is deactivated by the lack of activation information.

[0452] The gNB may include in the preemption activation/deactivation information information about the resources to be used for the preemption transmission. The resources may be time resource information or frequency resource information. The gNB may include information necessary to modulate and/or encode the preemption transmission in the preemption activation/deactivation information. The information necessary for modulation and/or coding may be, for example, modulation scheme information, coding rate information, or HARQ process number information.

[0453] The gNB may send preemptive activation/deactivation information with the PDCCH for the preemptive UE. Alternatively, new frequency/time resources may be provided for the transmission of information. The gNB may notify the preemptive UE in advance of the new frequency/time resource information.

[0454] The gNB may notify the preempted UE of the preemptive transmission information. The information may be identical to that in the preemption indication disclosed in the third embodiment. The information may include, for example, transmission timing information. The transmission timing information may be, for example, information about the timing with which the preemptive transmission is activated. The information may include some or all of the activation/deactivation information that the gNB notifies the preemptive UE. The preempted UE may determine the timing at which the preemptive transmission may occur using the information.

[0455] The gNB may send preemptive transmission information to the preempted UE using the PDCCH for the preempted UE. Alternatively, new frequency/time resources may be provided for the transmission of information. The gNB may notify the preempted UE of the new frequency/time resource information.

[0456] The third embodiment may reduce the wait time due to preemption. In addition, the third embodiment can guarantee reliability in connection with preemption.

[0457] First modification of the third embodiment

The following problem may occur in uplink preemption transmission. Specifically, when the gNB notifies the preempted UE of the timing information with which preemption transmission can occur, the preempted UE performs operations such as stopping uplink transmission or low power transmission, even if there are frequency/time resources, with which preemptive transfer does not actually occur. Thus, there is a problem of reducing the uplink transmission efficiency in the preempted UE.

[0458] The solution to the problem is described below.

[0459] The preemptive UE notifies the gNB of the information requesting the preemptive transmission. The information may be, for example, a predefined code. The predetermined code may be generated by a sequence that does not require or facilitates the encoding process and the decoding process. The predetermined code may be, for example, a Zadoff-Chu (ZC) code, an M-sequence, or a Hadamard code. The preemptive UE may notify the gNB of the information as soon as the preemptive transmission data occurs.

[0460] The following items (1) to (8) are disclosed as examples of predefined code information:

[0461] (1) a sequence in the ZC code (eg, q value);

[0462] (2) cyclic shift;

[0463] (3) number of characters;

[0464] (4) number of transmissions;

[0465] (5) frequency hopping information;

[0466] (6) sequence hopping information;

[0467] (7) transmission timing information; And

[0468] (8) a combination of items (1) to (7) above.

[0469] Item (1) may be, for example, the index of the root in the ZC code.

[0470] The number of characters in paragraph (3) may be, for example, one or more. For example, using a single character provides a quick notification of the code. For example, since the use of multiple symbols can increase the length of the code sequence, reliability can be improved.

[0471] In paragraph (4), the reliability of the notification of the code can be improved, for example, with multiple transmissions.

[0472] In paragraph (5), the reliability of the notification of the code can be improved, for example, using frequency diversity.

[0473] Avoiding by item (6) the interference that occurs when the same code is transmitted from other UEs and/or other base stations can improve the reliability of the code notification.

[0474] The information in clause (7) may be, for example, information about the time resolution with which the UE can transmit the code. The temporal resolution may be configured, for example, per symbol, each mini-slot, or per slot. Therefore, when the temporal resolution is configured for each character, it is possible to quickly notify the code.

[0475] Pieces of information about the predefined code may be defined in the standard. The pieces of information may be, for example, common to the UEs that the gNB serves. The pieces of information may be defined in a dedicated manner for each UE. The pieces of information may be determined using an identifier at the UE (eg, UE-ID). Since this eliminates the need for, for example, a UE code assignment process, the scope of the code assignment process can be reduced.

[0476] As an alternative example, the gNB may determine pieces of information about the predefined code and notify the UE about them. The pieces of information may be shared by the UEs that the gNB serves. The pieces of information may be defined using an identifier indicating a base station (eg, gNB-ID) or using an identifier indicating a cell (eg, cell-ID). Alternatively, the gNB may distribute the pieces of information in a dedicated manner appropriate to the UE. The gNB may broadcast the pieces of information to the respective UEs, or semi-statically notify each of the UEs of the pieces of information via dedicated RRC signaling. This may, for example, reduce the amount of signaling for notification of pieces of information. Alternatively, the gNB may dynamically notify pieces of information via MAC signaling. This can, for example, ensure reliability with retransmission control and flexibly allocate pieces of information according to the states of the surrounding cells or the UEs it serves, and so on. Alternatively, the gNB may notify via L1/L2 signaling. This provides, for example, a quick notification.

[0477] The number of pieces of information about the predetermined code may be one or more for each UE. When a plurality of codes are used, for example, the codes may be separately used with data amount information in an uplink preemptive transmission. This allows, for example, the gNB to perform flexible scheduling of the amount of data in an uplink preemptive transmission.

[0478] The bands on which the preemptive UE transmits the predetermined code may be all or part of the bands available to the preemptive UE. The bands on which the preemptive UE transmits the predetermined code may be non-consecutive bands per RB or per multiple RBs. The bands on which the preemptive UE transmits the predetermined code may be non-consecutive bands per RE or per multiple REs. The bands on which the preemptive UE transmits the predetermined code may be a combination of the two. In other words, the predetermined code may be allocated to non-consecutive bands per RE or to multiple REs in non-consecutive bands per RB or to multiple RBs. This provides, for example, a flexible band allocation.

[0479] The bands on which the preemptive UE transmits the predetermined code may be different bands from those available to the preempted UE. In other words, transmission of the uplink signal from the preempted UE and transmission of the predetermined code from the preemptive UE may be performed on different frequency bands. This may, for example, reduce the interference power when the gNB receives a predetermined code. This may result in improved reliability when transmitting a predetermined code from the preemptive UE.

[0480] As an alternative example, the bands on which the preemptive UE transmits the predetermined code may include some or all of the bands available to the preempted UE. In other words, transmission of the uplink signal from the preempted UE and transmission of the predetermined code from the preemptive UE may be performed over frequency bands that at least partially overlap. The gNB can simultaneously receive a predetermined code and an uplink signal. gNB may separate the predetermined code from the uplink signal. When separated, the gNB can extract the predetermined code from signals received simultaneously using the same template as that of the predetermined code. The gNB may process the remaining extracted signal as an uplink signal from the preempted UE. This can lead to, for example, efficient use of frequency resources in the communication system.

[0481] The bands on which the preemptive UE transmits the predetermined code may be defined in the standard, or determined by the gNB to notify this UE. For the notification method, the same method as for notification of predefined code pieces of information can be applied.

[0482] The timing with which the preemptive UE transmits a predetermined code may be predetermined in the standard. The preemptive UE may transmit the code, for example, in a symbol earlier by a predetermined duration from the start of the preemptive transmission. As an alternative example, the preemptive UE may transmit code in a predetermined symbol in a mini-slot that precedes one or more mini-slots in which preemptive transmission is performed.

[0483] The number of symbols earlier by a predetermined duration may be a plurality of symbols. The preemptive UE may transmit a predetermined code using some or all of the plurality of symbols. For example, when a portion of the plurality of symbols includes a timing that cannot be preempted, the preemptive UE may transmit a predetermined code using symbols obtained by excluding the timing that cannot be preempted from the plurality of symbols. This may, for example, increase flexibility in configuring the preemptive transmission. As an alternative example, the preemptive UE may repeatedly transmit a predetermined signal using all of the plurality of symbols. This may, for example, improve reliability when the preemptive UE transmits a predetermined code.

[0484] As an alternative example, the gNB may determine the timing with which the preemptive UE transmits a predetermined code. The gNB may broadcast or in a dedicated manner notify the timing of the UEs it serves. The gNB may notify via dedicated RRC signaling. When determining timing, a gNB may use the receive processing capabilities of its own gNB code, the transmit processing capabilities of the UE, or the transmit processing capabilities of its own gNB, and/or the receive processing capabilities of the UE of a predefined code, to be passed from the gNB to the preempted UE, which is described later. The processing capabilities for transmitting a code at the UE and/or the processing capabilities for receiving a predetermined code to be transmitted from the gNB to the preempted UE in that UE may, for example, be included in the capabilities of the UE. This allows, for example, the gNB to determine the timing so that it is not later than the processing times of the gNBs and UEs with code.

[0485] The preemptive UE may transmit a predetermined code with a different timing than the DMRS and/or PUCCH and/or SRS timings from the preempted UE. Transmissions with different timings may be applied when, for example, a predetermined code and DMRS, PUCCH or SRS are transmitted using the same frequency resources. The preemptive UE may change the transmission timing of the predetermined code. The transmission timing of the predetermined code may be changed, for example, within a range of a plurality of symbols in which the predetermined code may be transmitted from the preemptive UE. This allows, for example, a preemptive UE to quickly notify a gNB of a predefined code. The gNB may notify the preemptive UE of the DMRS and/or PUCCH and/or SRS transmission timing information from the preempted UE in advance. Alternatively, timing information may be predefined in the standard. This allows, for example, the preemptive UE to recognize the timing with which the predetermined code can be transmitted.

[0486] The preemptive UE may prevent the transmission of the predetermined code when the range in which the predetermined code can be transmitted does not include, for example, a timing different from the transmission timing of the DMRS and/or PUCCH and/or SRS from the preempted U.E. The preemptive UE may transmit the predetermined code in the next range in which the predetermined code may be transmitted. This may, for example, avoid the complexity of controlling a preemptive transmission in a communication system.

[0487] A method for changing the transmission timing of a predetermined code may be predefined in the standard. Examples of the change method may include a method for shifting the transmission timing of the predetermined code forward by one symbol within a range of a plurality of symbols in which the predetermined code can be transmitted, a method for shifting the transmission timing of the predetermined code backward by one symbol within range, and the combined method of the two.

[0488] As an alternative example, according to the method for changing the timing of the predetermined code, the gNB may notify the preemptive UE in a dedicated manner about the method of change. The gNB may notify, for example, via dedicated RRC signaling, MAC signaling, or L1/L2 signaling.

[0489] As an alternative example, the timing of the transmission of the predetermined code in the slot may be predefined in the standard, or the gNB may broadcast or notify the preemptive UE. The timing of the DMRS and/or PUCCH and/or SRS transmission from the preempted UE may be configured with the timing other than the transmission timing of the predetermined code. This may, for example, avoid the complexity of controlling a preemptive transmission in a communication system.

[0490] As an alternative example, the preemptive UE may transmit a predetermined code with the same timing as the timing of the DMRS transmission from the preempted base station. Transmission with the same timing may be applied, for example, when the predetermined code and DMRS are transmitted using different frequency resources.

[0491] gNB can allocate different sequences to a predefined code and DMRS. This allocation may be applied, for example, when the predetermined code and DMRS are transmitted on the same frequency resources. The gNB may notify the preemptive UE and/or the preemptive UE of the allocation. The gNB may notify, for example, via dedicated RRC signaling, MAC signaling, or L1/L2 signaling. This allows the gNB to receive both the predefined code and the DMRS at the same time.

[0492] As an alternative example, a predetermined code may be frequency multiplexed with DMRS. The frequency multiplexing may be performed, for example, per subcarrier, per multiple subcarriers, per resource element group (REG), or in another manner. The gNB may notify the preemptive UE and/or the preemptive UE of the frequency multiplexing method. The gNB may notify, for example, via dedicated RRC signaling, MAC signaling, or L1/L2 signaling. This allows, for example, a gNB to simultaneously receive both a predefined code and DMRS.

[0493] The gNB receives a predetermined code transmitted from the preemptive UE. Upon receipt of the code, the gNB recognizes the request to preempt.

[0494] The gNB notifies the preempted UE of the information indicating the preemptive transmission. The information may be, for example, a predefined code. The predetermined code may be identical to the code to be transmitted from the preemptive UE to the gNB as information indicating a request for preemptive transmission. The code to be used as the information to be transmitted from the gNB to the preempted UE may be identical or different from the code to be used as the information to be transmitted from the preemptive UE to the gNB. The gNB may transmit information to the preempted UE immediately after it recognizes the request to preempt.

[0495] The same information as the code information to be transmitted from the preemptive UE to the gNB can be applied to the predetermined code information. The same may be true for the method for determining predefined code information and the method for broadcasting and/or notifying the information from the gNB to the UEs it serves.

[0496] The number of pieces of information about the predetermined code may be one or more for each UE. When multiple codes are used, for example, the codes may be separately used with information about frequency resources to be used for preemptive transmission. This allows, for example, the gNB to perform flexible data volume scheduling in uplink preemption transmission.

[0497] The same method as for the timing with which the preemptive UE transmits the predetermined code can be applied to the transmission timing of the predetermined code.

[0498] Bands identical to those on which the preemptive UE transmits the predetermined code may be applied to the bands on which the gNB transmits the predetermined code. For example, the bands on which the gNB transmits the predetermined code may be all or part of the bands that are available to the preempted UE. As an alternative example, the vicinity of the center of the bands that the gNB uses can be used as the bands over which the gNB transmits a predetermined code. For example, using bands identical to those for the sync signal or broadcast channel allows the UE that is served by the gNB to receive a common code.

[0499] The preempted UE receives a predetermined code to be transmitted from the gNB. Upon receipt of the gNB code, it recognizes the occurrence of a preemptive transmission.

[0500] Upon receipt of the code, the preempted UE may stop the uplink transmission that overlaps the preemptive transmission or perform the operations indicated in paragraphs (1) to (4) disclosed in the third embodiment as examples of the uplink transmission that overlaps displacement transmission. Operations at the preempted UE for uplink transmission that overrides the preemptive transmission may be defined in the standard, or the gNB may broadcast them in advance, or the gNB may notify the preempted UE in a dedicated manner. The methods described in the third embodiment can be applied to the definition in the standard, broadcast or dedicated notification.

[0501] The gNB notifies the preemptive UE of the uplink grant information for preemptive transmission. The information may be, for example, an uplink grant with the PDCCH for the preemptive UE. As an alternative example, the information may be, for example, a predefined code. The predetermined code may be identical to the code to be transmitted from the preemptive UE to the gNB as information indicating a request for preemptive transmission. The code to be used as the information to be transmitted from the gNB to the preemptive UE may be the same or different from the code to be used as the information to be transmitted from the preemptive UE to the gNB.

[0502] The same information as the information about the code to be transmitted from the preemptive UE to the gNB can be applied to the information about the predefined code that the gNB needs to notify the preemptive UE. The same may be true for the method for determining predefined code information and the method for broadcasting and/or notifying the information from the gNB to the UEs it serves.

[0503] The number of pieces of information about the predefined code that the gNB must notify the preemptive UE may be one or more for each UE. When multiple codes are used, for example, the codes may be separately used with information about frequency resources to be used for preemptive transmission. Alternatively, the codes may be separately used with the transmission power information in connection with the preemption. This allows, for example, the gNB to perform flexible scheduling in uplink preemption transmission. The gNB may notify the preemptive UE of multiple pieces of information in advance.

[0504] The same method as for the timing with which the preemptive UE transmits the predetermined code can be applied to the transmission timing of the predetermined code that the gNB needs to notify the preemptive UE.

[0505] Bands identical to those on which the preemptive UE transmits the predetermined code may be applied to the bands on which the gNB transmits the predetermined code to the preemptive UE. The bands may be, for example, all or part of the bands available to the preemptive UE. As an alternative example, the bands may be in the vicinity of the center of the bands that the gNB uses. For example, using bands identical to those for the sync signal or broadcast channel allows UEs that are served by the gNB to receive a common code.

[0506] The preemptive UE performs preemptive transmission with the uplink grant information.

[0507] If no uplink grant information is received, the preemptive UE may determine that the preemption request has failed. The preemptive UE may make a determination, for example, when the preemptive UE cannot receive the uplink grant information before a predetermined time reference.

[0508] The preemptive UE may retransmit the preemption request. The preemptive UE may retransmit the preemption request, for example, upon determining that the preemption request has failed. The preemptive UE may retransmit the preemption request with a timing that the preemption request can be transmitted with immediately after it makes the determination. Therefore, for example, the preemptive UE can quickly make a preemption request.

[0509] The preemptive UE may have a retransmission prohibition timer in the preemption request. The preemptive UE does not need to transmit or retransmit the preemption request before the retransmission inhibit timer expires. This may, for example, prevent depletion of frequency/time resources due to repeated retransmission of the preemption request.

[0510] The retransmission inhibit timer for the retransmission request may be started, for example, upon transmission of the preemption request. The timer may be stopped, for example, upon receiving an uplink grant from the gNB.

[0511] The timer value may be predefined in the standard, or determined, or broadcast or notified in a dedicated manner to the preemptive UE. The gNB may notify, for example, through RRC signaling, MAC signaling, or L1/L2 signaling. Determining the timer value by the gNB provides, for example, flexible control according to the frequency/time resource usage state.

[0512] FIG. 34 illustrates an example in which a predetermined code is used as information indicating a preemption request. Fig. 34 illustrates an example of FDM. Fig. 34 illustrates an example in which the preempted UE performs eMBB communication while the preemptive UE performs URLLC communication. On FIG. 34, the same numbers are assigned to signals that are in common with those in FIG. 32 and their general description is omitted.

[0513] In FIG. 34, the preemptive UE transmits code 4201 to the gNB indicating a preemption request. The preemptive UE may transmit code 4201 on bands to be used for preemption communication or on bands other than such bands. Upon receipt of code 4201, the gNB recognizes the request to preempt. The gNB sends an uplink preemption indication 4202 to the preempted UE. Uplink wipe indication 4202 may be identical to code 4201 or identical to that in the third embodiment. The gNB may send an uplink preemption indication 4201 on bands to be used for PDCCH 4003 and PDSCH 4004, or on bands other than such bands.

[0514] The first modification can be combined with the third embodiment for use. For example, the base station and the gNB notify the preemptive UE of time resources and/or frequency resources with which preemption communication can occur. The notification may include information about operations that override the preemption transmission from the uplink transmission operations at the UE. The preemptive UE may transmit the predetermined code described in the first modification to the base station, and the base station may transmit the predetermined code described in the first modification to the preempted UE. Upon receiving the predetermined code, the preempted UE may stop the uplink transmission or perform the operations of (1) to (4) disclosed as examples of an uplink transmission that overrides the preemptive transmission. When not receiving the predetermined code, the preempted UE may continue to transmit the uplink. Since this allows, for example, the preempted UE to perform uplink transmission with frequency/time resources with which no preemption transmission actually occurs, the uplink transmission efficiency of the preempted UE can be guaranteed.

[0515] Since the first modification does not require or facilitates the processes of decoding the SR in the gNB and encoding the uplink grant and the uplink preemption indication, fast notification is possible. Since the preempted UE can perform uplink transmission with frequency/time resources by which no preemption transmission actually occurs, the efficiency of uplink transmission in the preempted UE can be guaranteed.

[0516] Fourth embodiment

In the coexistence of LTE-NR with the same downlink carriers, the gNB transmits the NR signal with an MBFSN subframe in LTE. The gNB transmits the NR signal using the MBFSN subframe in LTE. gNB may signal NR using a non-MBFSN subframe. gNB can use mini-slots to transmit the NR signal.

[0517] The gNB and the LTE base station (eNB) may or may not be base stations that configure the DCs in the UE. For example, gNB and eNB may be adjacent base stations. This may, for example, reduce gNB interference in an LTE-only UE.

[0518] The NR signal may be an SS signal, a PBCH signal, or include both. The gNB may transmit SS and PBCH through each beam in one block (may be referred to as an SS block hereinafter).

[0519] The gNB may suddenly transmit an SS signal and a PBCH signal (may be referred to as a burst of SS pulses hereinafter). The gNB may transmit the SS signal and/or the PBCH signal, for example, at a predetermined time. The gNB may transmit, for another predetermined period, the SS signal and/or the PBCH signal at a predetermined time. The gNB may transmit in the SS block the SS signal and/or the PBCH signal at a predetermined time.

[0520] The application of the above methods creates the following problem. In particular, the burst signal SS in NR competes with signals in non-MBFSN in LTE, such as synchronization signal, broadcast information and paging information. Therefore, the UE has a problem that it is unable to create synchronization with the eNB and/or gNB in the coexistence of LTE-NR.

[0521] The solution to the problem is disclosed below.

[0522] Priorities are assigned to a signal in a non-MBFSN subframe in LTE and a burst signal SS in NR. For example, only one of the signals is transmitted in a contention section between the two signals. The signal in a non-MBFSN subframe in LTE may be, for example, a sync signal in LTE, a broadcast channel in LTE, or a paging signal in LTE. The burst signal SS in NR can be, for example, a synchronization signal in NR or a broadcast channel in NR.

[0523] For example, a signal may be prioritized in a non-MBFSN subframe in LTE. This may, for example, reduce interference in a non-MBFSN subframe in LTE. The gNB may prevent all or part of the SS burst signaling in a subframe that overlaps with a non-MBFSN subframe in LTE. An overlapping subframe may be replaced by an overlapping slot, an overlapping mini-slot, or an overlapping symbol. As an alternative example, the gNB may prevent transmission of only SS burst signals in the NR that overlap the signals in the non-MBFSN subframe. This may prevent the burst of pulses SS from being stopped unnecessarily.

[0524] The gNB may transmit a burst signal in NR that overlaps a signal in a non-MBFSN subframe in LTE. Both signals may be mutually separable signals. For example, one of the signals may be a signal with a predefined pattern. The mutually separable signals may be, for example, a combination of SS in LTE and PBCH in NR, a combination of PBCH in LTE and SS in NR, or a combination of paging in LTE and SS in NR. The UE may receive overlapping signals and separate the signals. For example, the UE may extract a signal with a predetermined pattern and obtain the difference between the original receive signal and the extracted signal as a different signal. This allows, for example, the UE to receive both signals in LTE and NR.

[0525] An eNB may change paging transmission timings for the UEs it serves. An eNB may, for example, integrate paging timings for the UEs it serves into one or more. This can, for example, reduce the overlap between the burst signal SS in NR and paging transmission timings in LTE. Thus, the gNB does not need to stop transmitting the SS burst, and the transmission of the SS burst in the NR, which interferes with the eNB signal, can be reduced.

[0526] As an example of changing paging transmission timings, multiple POs of the UEs they serve may be integrated into one PO. This may, for example, avoid overlap between SS burst transmission in NR and paging transmission timings in LTE. As an exemplary method for integrating multiple POs into one PO, the value of the Ns parameter indicating the number of subframes over which the paging signal is distributed in one radio frame may be 1, as described in Non-Patent Document 17 (3GPP TS 36.304 V14.4.0). The eNB may determine the value of the Ns parameter as 1 by limiting the value of the parameter nB described in Non-Patent Document 17 (3GPP TS 36.304 V14.4.0) to less than or equal to T times 1. The eNB may broadcast the value of the changed nB parameter to the UE, which he serves. For example, SIB2 can be used for broadcast transmission (see Non-Patent Document 18 (3GPP TS 36.331)). This allows, for example, an eNB to integrate the POs of the UEs it serves into one PO with less signaling.

[0527] Changing the paging transmission timing may be, for example, changing a paging frame (PF), changing a paging event (PO), or changing a paging transmission period. The paging transmission timing change may be a combination of at least two of these options.

[0528] When changing the paging transmission timing, the eNB may change the parameter to be used to determine the paging transmission timing. The parameter may be, for example, UE-ID. The eNB may notify the UE of the parameter change information.

[0529] An eNB may increase the number of UEs to which paging can be transmitted with one paging transmission timing. The amount to be increased may, for example, be predetermined in the standard. This allows, for example, an eNB to transmit pages to multiple UEs with fewer paging transmission timings.

[0530] An eNB may notify surrounding eNBs of the information. Surrounding eNBs may be, for example, multiple eNBs that belong to the same tracking area as this eNB. A plurality of eNBs may page the UE with the information. This ensures, for example, smooth paging operations on the occurrence of mobility in the UE.

[0531] The eNB may notify the higher level NW device of the information. The eNB may notify through the interface between the higher level NW device and the base station. The high-level NW device may be AMF or SMF. The higher-level NW device may send a notification to the eNB indicating whether to accept or reject the parameter change.

[0532] A high-level NW device may notify the information of the eNBs it serves. The eNBs it serves may be, for example, a plurality of eNBs that belong to the same tracking area as that of the eNB. A plurality of eNBs may page the UE with the information. This ensures, for example, smooth paging operations on the occurrence of mobility in the UE.

[0533] The gNB can obtain non-MBSFB subframe information in LTE. The following items (1) to (5) are disclosed as non-MBSFB subframe information pieces in LTE.

[0534] (1) frame timing in LTE;

[0535] (2) SS information in LTE;

[0536] (3) information about communication systems in LTE;

[0537] (4) paging timing information; And

[0538] (5) a combination of items (1) to (4) above.

[0539] The gNB can obtain the timing in LTE in paragraph (1) through the cell search described in the first embodiment. The gNB may have a function to perform a cell search. The gNB may have a time reference to perform the cell search. As an alternative example, the gNB may query the eNB for information about the frame timing difference between LTE and NR. The eNB may notify the gNB of the information. The request and/or notification may be performed via an interface between base stations, such as an Xn interface. The eNB may receive the frame timing in the NR. The eNB may obtain frame timing in NR, for example, through cell search. This allows, for example, a gNB to obtain information about a non-MBSFB subframe in LTE.

[0540] The gNB may request the information in paragraph (2) from the eNB. The eNB may notify the gNB of the information in paragraph (2). The request and/or notification may be performed via an interface between base stations, such as an Xn interface. The information in item (2) may be, for example, code sequence and cyclic shift information of a PSS in LTE or code sequence and cyclic shift information of an SSS in LTE. gNB can perform cell search using the information in item (2). This allows, for example, the gNB to quickly perform cell search processes. This may also, for example, prevent incorrect LTE cell discovery in the gNB.

[0541] As an alternative example, the gNB may obtain the information in paragraph (2) through a cell search. This may, for example, reduce the amount of signaling between base stations.

[0542] The information in item (3) may include information about the duplex system (eg, TDD or FDD) or half-duplex system in LTE, or cyclic prefix information (eg, cyclic prefix duration length). The gNB may request the information in paragraph (3) from the eNB. The eNB may notify the gNB of the information. The request and/or notification may be performed via an interface between base stations, such as an Xn interface. The gNB can extract the signal position in the non-MBSFN subframe in LTE using the information. This allows, for example, a gNB to quickly obtain non-MBSFN subframe information in LTE.

[0543] As an alternative example, in clause (3), the gNB may obtain the information in clause (3) from broadcast information in LTE. This may, for example, reduce the amount of signaling between base stations.

[0544] The information in item (4) may include information about, for example, paging frame (PF), paging event (PO), and paging period that are used in the eNB. The gNB may request information from the eNB. The eNB may notify the gNB of the information. The eNB may notify the information after the gNB issues a request or when the information changes. The gNB may transmit the burst signal SS in the non-MBSFN subframe with the help of the information. The gNB may transmit the burst signal SS, for example, in a subframe in which the eNB does not distribute paging information. This allows the gNB to maintain the timing for transmitting the burst signal SS.

[0545] The information in clause (4) may include information about, for example, a subframe that the eNB does not actually use for paging transmission. The information in clause (4) may be information about, for example, the subframe that the eNB actually uses to transmit the paging. The gNB may transmit, with the information, a burst signal SS in a subframe that is not actually used for paging transmission. This allows, for example, the gNB to keep a time reference for transmitting the burst signal SS.

[0546] The high-level NW device may notify the gNB of paging information from the eNB with respect to the UE. The higher level NW device may notify the paging information to the UE. The high-level NW device may notify the eNB and gNB of the information at the same time or at different timings. The gNB may extract from the notification the subframe in which the eNB actually sends a paging signal to the UE. The gNB may transmit the burst signal SS in a subframe different from the retrieved subframe. This allows, for example, the gNB to keep a time reference for transmitting the burst signal SS.

[0547] The gNB may prevent some of the signals in the SS burst from being transmitted. The gNB may, for example, reduce the number of SS blocks to be transmitted as an SS burst. This can, for example, reduce interference with a non-MBSFN subframe in LTE.

[0548] The gNB may reorder the SS blocks constituting the SS burst. gNB may semi-statically or periodically reorder SS blocks. This allows, for example, the gNB to transmit all SSs to the UE even when contention occurs with a signal in a non-MBSFN subframe in LTE.

[0549] The gNB may reorder SS blocks per subframe. For example, when transmitting SS blocks #0 and #1 in subframe #0 and SS blocks #2 and #3 in subframe #1, the gNB may reorder SS blocks to transmit SS blocks #2 and #3 in subframe #0 and blocks #0 and #1 SS in subframe #1. This, for example, facilitates control over reordering.

[0550] As an alternative example, the gNB may reorder SSs per slot. This ensures that the SS blocks are reordered, for example, even when the symbol lengths in LTE and NR are different.

[0551] As an alternative example, the gNB may reorder SS blocks per SS block. This provides, for example, flexible control in gNB.

[0552] FIG. 35 illustrates an example of reordering of SS blocks in an SS burst in NR. On FIG. 35, the top tier illustrates signals in LTE and the bottom tier illustrates signals in NR. In both the top and bottom tiers, the left diagrams illustrate 5 milliseconds before the SS blocks are reordered, and the right diagrams illustrate 5 milliseconds after the SS blocks are reordered. Fig. 35 illustrates the case where the symbol lengths in NR and LTE are the same and the number of SS blocks in NR is eight.

[0553] In FIG. 35, SS 4501, PBCH 4502, PDCCH 4503 in paging signal and paging signal 4504 are signaled in non-MBSFN subframes from the eNB.

[0554] SS block #0 (SS block 4510) and SS block #1 (SS block 4511) in subframe #0 are not transmitted before the SSs are reordered in FIG. 35 because they overlap SS 4501 and PBCH 4502. SS block #2 (SS block 4512) to SS block #7 (SS block 4517) are transmitted in subframes #1 to #3.

[0555] In the illustration of FIG. 35, after the SSs are reordered, the SSs in subframes #0 and #1 are reordered. As a result, SS block #2 (SS block 4522) and SS block #3 (SS block 4523) in subframe #0 are transmitted, and SS block #0 (SS block 4520), SS block #1 (SS block 4521) and blocks are transmitted. from block #4 SS (block 4514 SS) to block #7 SS (block 4517 SS) in subframes #1 to #3.

[0556] After the reordering period elapses after the SSs are reordered in FIG. 35, the arrangement of the SSs can be restored to that before the reordering of the SSs. This may, for example, prevent the transmission stop state from continuing in any of the SS blocks #1 to #3.

[0557] FIG. 36 is a timing diagram illustrating the transmission of SS blocks in NR that do not overlap non-MBSFN signals in LTE. Fig. 36 illustrates the overlap between a non-MBSFN subframe in LTE and an SS burst in NR when the symbol lengths in LTE and NR are different. Fig. 36 illustrates the case where the symbol length in NR is half that in LTE, i. e. the subcarrier interval in NR is 30 kHz, which is twice as long as in LTE.

[0558] In FIG. 36, SS block #0 (SS block 4610) in NR is transmitted because it overlaps neither SS 4601 nor PBCH 4602 in LTE. SS block #1 (SS block 4611) in NR is not transmitted because it overlaps SS 4601 in LTE. SS block #2 (SS block 4612) and SS block #3 (SS block 4613) are not transmitted in NR because they overlap PBCH 4602 in LTE.

[0559] A method for looping SS blocks can be used as a method for reordering SS blocks. For example, a predetermined number of repetitions of an SS burst in which blocks #0 to #7 SS are arranged in this order may be followed by a predetermined number of repetitions of an SS burst in which blocks #6, #7, #0, #1, #2, #3, #4 and #5 SS are in that order. Then, a burst SS may be transmitted in which blocks #4, #5, #6, #7, #0, #1, #2, and #3 SS are in that order. Since this can, for example, equalize the acquisition capabilities of the SSs across each beam, the maximum value of the time it takes for the terminals to synchronize can be reduced.

[0560] In another method for SS block looping, SS block looping may be per SS block, per slot, or per subframe. The direction of the loop can be forward or backward with respect to the direction of time.

[0561] The gNB may notify the UE of the SS reordering information in the NR. This allows, for example, the UE to continue to acquire SSs in the NR even after the SSs are reordered.

[0562] The information may be included in, for example, system information. Information may be included in the minimum SI. The gNB may broadcast the information to the UEs it serves or notify the information as Remaining Minimum System Information (RMSI). Alternatively, the gNB may broadcast or in a dedicated manner notify the information of the UEs it serves as another SI.

[0563] A carrier other than the carrier in the NR in which the SS blocks are reordered can be used for broadcasting or notification of information. This allows, for example, the UE to quickly understand the information. Alternatively, an NR carrier may be used in which the SSs are reordered. Since this eliminates the need, for example, for a plurality of other carriers in the NR to broadcast or SS block reorder notification, the amount of signaling can be reduced.

[0564] For example, an eNB may broadcast or notify information. An eNB can broadcast or notify information in exactly the same manner as when a gNB broadcasts or notifies information. This allows, for example, the UE to quickly understand the information.

[0565] Alternatively, gNBs and eNBs do not need to be notified of the information. The UE may automatically reacquire the SSs after reordering the SSs in the NR. This can reduce the amount of signaling.

[0566] The following items (1) to (4) are disclosed as examples of pieces of information included in the information:

[0567] (1) SS block reordering period information;

[0568] (2) information about SS blocks to be reordered;

[0569] (3) reordering method information; And

[0570] (4) a combination of items (1) to (3) above.

[0571] In item (1), the period may be, for example, a subframe. As an alternative example, the period may be a value corresponding to the maximum duration of the SS pulse burst (eg, 5 milliseconds). As an alternative example, the period may be a radio frame (eg, 10 milliseconds) or a value corresponding to the transmission period of the SS burst.

[0572] In paragraph (2), the information may be, for example, the number of SS blocks to be reordered. The information may be, for example, SS blocks #0 and #1 and SS blocks #2 and #3 in the example of FIG. 35. This may, for example, reorder SS blocks in a flexible manner. As an alternative example, slot numbers may be used. This ensures reordering, for example, even when the symbol lengths in LTE and NR are different. As an alternative example, subframe numbers may be used. This can, for example, reduce the amount of reordering processes.

[0573] As an alternative example, in paragraph (2), the information may be information about a reordering unit. The reordering unit information can be applied to, for example, a cyclic reordering. The reordering unit may be, for example, an SS block, a slot, or a subframe.

[0574] In item (3), the information may be, for example, information indicating shuffling of SS blocks or information indicating cyclic reordering of SS blocks. The information may include information indicating whether the SS blocks are forward looped or looped back in the time direction.

[0575] When reordering the SS blocks corresponding to a beam, the gNB can automatically change the timing of the paging transmission in the beam. The UE may automatically change paging reception timing to follow the SS reordering. The association between SS block orders and paging transmission timings may be defined in the standard. Since this can, for example, introduce connectivity into the relationship between SSs and paging transmission/reception timings, paging control in the gNB is facilitated.

[0576] The UE may obtain paging reception timing information. The UE may receive information after the SSs are reordered. The paging reception timing information may be, for example, a control channel resource set (CORESET) including paging information.

[0577] As an alternative example, the gNB may fix the timing of the paging transmission in the beam. Since this, for example, fixes the timing of paging reception at the UE, the amount of processing regarding the paging at the UE can be reduced.

[0578] The timing of the PRACH transmission from the UE across the beam when the SSs are reordered may be identical to the paging transmission/reception timings.

[0579] As an alternative example of prioritizing a signal in a non-MBFSN subframe in LTE and an SS burst signal in NR, the SS burst signal in NR may be prioritized over a signal in a non-MBFSN subframe in LTE. This can, for example, reduce the interference received by the SS burst in the NR. The eNB may not allow all or part of the signals in the non-MBFSN subframe in LTE to be transmitted in the subframe overlapping the SS burst in NR. An overlapping subframe may be replaced by an overlapping slot or an overlapping mini-slot. As an alternative example, the eNB may only prevent signaling in a non-MBFSN subframe in LTE that overlaps SS burst signals in NR. This may prevent the non-MBFSN subframe from being unnecessarily stopped in LTE.

[0580] The eNB may transmit a signal in a non-MBFSN subframe in LTE that overlays the SS burst signal in NR. Both signals may be mutually separable signals. For example, one of the signals may be a signal with a predefined pattern. The signals to be separated may be identical to those applied when priority is set for a signal in a non-MBFSN subframe in LTE. This allows, for example, the UE to receive both signals in LTE and NR.

[0581] An eNB may change paging transmission timings for the UEs it serves. An eNB may, for example, integrate paging transmission timings for the UEs it serves into one or more. This can, for example, reduce the overlap between the burst signal SS in NR and paging transmission timings in LTE. Thus, the eNB does not need to stop paging transmission, and interference with SS burst signals in NR can be reduced.

[0582] As an example of changing paging transmission timings, POs of the UEs they serve may be integrated into one PO. This may, for example, avoid an overlap between the SS burst transmission in NR and paging transmission timings in LTE. As an exemplary method for integrating multiple POs into one PO, the value of the Ns parameter indicating the number of subframes over which the paging signal is distributed in one radio frame may be 1, as described in Non-Patent Document 17 (3GPP TS 36.304 V14.4.0). The eNB may determine the value of the Ns parameter as 1 by limiting the value of the nB parameter described in Non-Patent Document 17 (3GPP TS 36.304 V14.4.0) to less than or equal to T times 1. The eNB may broadcast the value of the changed nB parameter to the UE, which he serves. For example, SIB2 can be used for broadcast transmission (see Non-Patent Document 18 (3GPP TS 36.311)). This allows, for example, an eNB to integrate the POs of the UEs it serves into one PO with less signaling.

[0583] Changing the paging transmission timing may be, for example, changing a paging frame (PF), changing a paging event (PO), or changing a paging transmission period. The paging transmission timing change may be a combination of at least two of these options.

[0584] When changing the paging transmission timing, the eNB may change the parameter to be used to determine the paging transmission timing. The parameters may be, for example, UE-ID. The eNB may notify the UE of the parameter change information.

[0585] An eNB may notify surrounding eNBs of the information. Surrounding eNBs may be, for example, multiple eNBs that belong to the same tracking area as this eNB. A plurality of eNBs may page the UE with the information. This ensures, for example, smooth paging operations on the occurrence of mobility in the UE.

[0586] The eNB may notify the higher level NW device of the information. The eNB may notify through the interface between the higher level NW device and the base station. The high-level NW device may be AMF or SMF. The higher-level NW device may send a notification to the eNB indicating whether to accept or reject the parameter change.

[0587] A high-level NW device may notify the information of the eNBs it serves. The eNBs it serves may be, for example, multiple eNBs that belong to the same tracking area as that of the eNB. A plurality of eNBs may page the UE with the information. This ensures, for example, smooth paging operations on the occurrence of mobility in the UE.

[0588] The eNB may obtain information about the burst of SS pulses in the NR. The following items (1) to (4) are disclosed as pieces of NR burst information SS:

[0589] (1) frame timing in NR;

[0590] (2) SS information in NR;

[0591] (3) information about communication systems in NR; And

[0592] (4) a combination of items (1) to (3) above.

[0593] The eNB may obtain the timing in NR in item (1) through the cell search described in the first embodiment. P-SS and S-SS can be obtained by cell search. The eNB may have a function to perform a cell search. The eNB may have a time reference to perform the cell search. As an alternative example, the eNB may query the gNB for information about the frame timing difference between LTE and NR. The gNB may notify the eNB of the information. The request and/or notification may be performed via an interface between base stations, such as an Xn interface. gNB can obtain frame timing in LTE. The gNB may obtain frame timing in LTE, for example, through cell search. This allows, for example, the eNB to receive information about the SS burst in the NR.

[0594] The eNB may request the information in paragraph (2) from the gNB. The gNB may notify the eNB of the information in paragraph (2). The request and/or notification may be performed via an interface between base stations, such as an Xn interface. The information in item (2) may be, for example, P-SS code sequence or cyclic shift information in NR or S-SS code sequence and NR cyclic shift information. The information in item (2) may include information about the duration of the SS burst in the NR. The information in item (2) may include information about the burst period of the SS in the NR. The eNB may perform cell search using the information in item (2). This allows, for example, the eNB to quickly perform cell search processes. This may, for example, prevent incorrect detection of the NR cell in the eNB.

[0595] As an alternative example, the eNB may obtain the information in paragraph (2) through cell search. This may, for example, reduce the amount of signaling between base stations.

[0596] The information in clause (3) may include multiplexing system information (eg, TDM or FDM) in the NR or cyclic prefix information (eg, cyclic prefix duration length). The information in item (3) may include information about the symbol length in the NR. The eNB may request the information in paragraph (3) from the gNB. The gNB may notify the eNB of the information. The request and/or notification may be performed via an interface between base stations, such as an Xn interface. The eNB can extract the signal position in the SS burst in the NR using the information. This allows, for example, the eNB to quickly obtain information about the SS burst in the NR.

[0597] As an alternative example of paragraph (3), the eNB may obtain the information in paragraph (3) from the broadcast information in the NR. This may, for example, reduce the amount of signaling between base stations.

[0598] Another solution is described. A signal in a non-MBFSN subframe in LTE and an SS burst signal in NR may be transmitted simultaneously. Both signals may be mutually separable signals. For example, one of the signals may be a signal with a predefined pattern. The mutually separable signals may be, for example, a combination of SS in LTE and PBCH in NR, a combination of PBCH in LTE and SS in NR, or a combination of paging in LTE and SS in NR. The UE may receive overlapping signals and separate the signals. For example, the UE may extract a signal with a predetermined pattern and obtain the difference between the original receive signal and the extracted signal as a different signal. This allows, for example, the UE to receive both signals in LTE and NR.

[0599] Another solution is disclosed. An offset in the frame boundary between LTE and NR can be provided. The offset may be provided, for example, per subframe, per slot, or per symbol. The offset may be a unit less than a character, such as a unit of minimum system time (eg, Ts).

[0600] The gNB and the eNB may transmit SS burst signals in NR that overlap the signals in the non-MBFSN subframe in LTE. gNBs and eNBs can transmit separable signals disclosed as a signaling solution. This allows, for example, coexistence between a signal in a non-MBFSN subframe in LTE and an SS symbol burst signal in NR.

[0601] FIG. 37 illustrates an example in which offset is provided at the frame boundary between LTE and NR. Fig. 37 illustrates the case where the frame boundary in NR is later than that in LTE by one symbol. Fig. 37 illustrates the case where the symbol lengths in LTE and NR are the same and the number of SS blocks in an SS burst in NR is eight.

[0602] In FIG. 37, a frame boundary delay in NR from that in LTE by one symbol causes the first PBCH 4710 in subframe #0 in NR to overlap SS 4701 in LTE. Moreover, the second SS 4711 in subframe #0 in NR overlaps PBCH 4702 in LTE. Because PBCH 4710 and SS 4710 are mutually separable, the gNB can carry PBCH 4710. The same is true for SS 4711 in NR.

[0603] In the example of FIG. 37, a non-MBFSN subframe in LTE and an SS burst in NR can exist by allowing simultaneous transmission of the SS in LTE and the PBCH in the first block of the SS in NR. This provides, for example, fast and synchronous acquisition of the UE in NR.

[0604] gNB may change frame timing in NR. The gNB may notify or broadcast the change to the UEs it serves. The gNB may notify the NW higher level device of the frame timing change. The gNB can perform notification through the interface between the higher level NW device and the base station. The high-level NW device may be AMF or SMF. The higher-level NW device may send a notification to the gNB indicating whether to accept or reject the frame timing change. A higher-level NW device may issue an instruction to the gNBs it serves to change the frame timing. A high-level NW device may issue an instruction to neighboring gNBs of the gNB. This allows, for example, neighboring gNBs, including gNBs, to match frame timings in the NR.

[0605] An eNB may change frame timing in LTE. The same method as applied to gNB can be applied to this change to change the frame timing in NR.

[0606] Information about changing the frame timing in NR and/or LTE may be included in, for example, system information. Change information may be included in the minimum SI. The eNB may broadcast change information to the UEs it serves or notify the information as Remaining Minimum System Information (RMSI). Alternatively, the eNB may broadcast or in a dedicated manner notify the change information to the UEs it serves as another SI.

[0607] A carrier other than the carrier in NR that coexists with that in LTE may be used for broadcast or change information notification. This allows, for example, the UE to quickly understand the information. Alternatively, a carrier in NR that coexists with one in LTE can be used for broadcast and notification of change information. Since this eliminates the need for, for example, multiple other carriers in the NR to broadcast or notify change information, the amount of signaling can be reduced.

[0608] For example, an eNB may broadcast or notify change information. An eNB can broadcast or notify information in exactly the same manner as when a gNB broadcasts or notifies information. This allows, for example, the UE to quickly understand the change information.

[0609] Alternatively, gNBs and eNBs do not need to be notified of the change information. The UE may automatically follow the frame timing change in LTE and NR. This can reduce the amount of signaling.

[0610] Another solution is disclosed. The arrangement of SS blocks in the SS burst in NR can be changed. For example, signals in SS blocks in NR may be arranged in mini-slots. One SS block can be placed in different mini-slots. For example, two symbols out of four symbols in one SS block may be spaced in one mini-slot, and the remaining two symbols may be spaced in the next mini-slot. The changed constellation may be, for example, a constellation that avoids CRS in LTE. This may, for example, prevent interference between SSs in NR and CRSs in LTE.

[0611] A plurality of SS block patterns in an SS burst in NR may be predefined in the standard. Multiple patterns may be defined for a single character length. The UE may acquire SSs synchronously using the pattern information. Therefore, the UE can automatically acquire SSs that are arranged in a plurality of patterns.

[0612] The gNB may notify the UE of the NR's SS block spacing change information. The information may be, for example, information indicating which pattern the SS blocks are arranged in. This allows, for example, the UE to continue capturing the SSs in the NR even after the spacing of the SSs in the NR is changed.

[0613] The information may be included in, for example, system information. Information may be included in the minimum SI. The gNB may broadcast the information to the UEs it serves or notify the information as Remaining Minimum System Information (RMSI). Alternatively, the gNB may broadcast or dedicated information notification to the UEs it serves as another SI.

[0614] A carrier other than the carrier in the NR in which the SS block arrangement is changed can be used for broadcasting or notification of information. This allows, for example, the UE to quickly understand the information. Alternatively, a carrier in the NR in which the SS block spacing has been changed can be used for broadcasting or information notification. Since this eliminates the need for, for example, a plurality of other carriers in the NR to broadcast or notify the SS remapping information, the amount of signaling can be reduced.

[0615] For example, an eNB may broadcast or notify information. An eNB can broadcast or notify information in exactly the same manner as when a gNB broadcasts or notifies information. This allows, for example, the UE to quickly understand the information.

[0616] Alternatively, gNBs and eNBs do not need to be notified of the information. The UE may automatically reacquire SSBs in the NR whose spacing has been changed. This can reduce the amount of signaling.

[0617] A plurality of solutions disclosed in the fourth embodiment may be combined. For example, a signal in a non-MBFSN subframe in LTE and an SS burst signal in NR may be transmitted simultaneously and an offset may be provided at the frame boundary between LTE and NR. This allows, for example, the coexistence of a non-MBFSN subframe signal in LTE and an SS burst signal in NR. Even when the symbol lengths in LTE and NR are different, a non-MBFSN subframe signal in LTE and an SS burst signal in NR can coexist.

[0618] FIG. 38 illustrates an example of changing the spacing of the SS pulse burst in NR. Fig. 38 illustrates an exemplary spacing of four SS block symbols into two symbols. Fig. 38 also illustrates an example in which SSs in NR are spaced in the first two symbols and PBCHs in NR are spaced in the last two symbols. On FIG. 38, the vertical striped SS block represents the SS, and the horizontal striped SS block represents the PBCH.

[0619] In FIG. 38 SS 4810 and PBCH 4811 in NR are spaced to avoid CRS 4800, SS 4801, PBCH 4802 and paging signal 4805 in LTE. SS 4820 in NR is spaced in an area overlapping PBCH 4802 in LTE to avoid CRS 4800. PBCH 4821 in NR is spaced to overlap SS 4801 in LTE. SS 4801 in LTE and PBCH 4821 in NR in FIG. 38 may be mutually separable signals. PBCH 4802 in LTE and SS 4820 in NR in FIG. 38 may be mutually separable signals.

[0620] With the deployment illustrated in FIG. 38, the signal in block SS in NR avoids CRS, and SS in LTE and PBCH are mutually separable. Thus, coexistence is possible between a signal in an SS block in NR and a signal in a non-MBFSN subframe in LTE.

[0621] The fourth embodiment enables, in LTE-NR coexistence, coexistence of a non-MBFSN subframe signal in LTE and an SS burst signal in NR, and can make communication using LTE compatible with communication using NR. Therefore, the utilization efficiency of the communication system is increased.

[0622] First modification of the fourth embodiment

Preemptive communication can be applied in the coexistence of LTE-NR. The push communication may be performed in the uplink or in the downlink. For example, the UE may perform uplink communication with the gNB as an interruption during uplink transmission to the eNB during uplink preemption. As an alternative example, the gNB may perform a downlink transmission to the UE as an interruption during the downlink transmission from the eNB to the UE in downlink preemption. While these examples show that the gNB transmits and receives preemptive communications to and from the UE, the eNB may transmit and receive preemptive communications to and from the UE.

[0623] LTE-NR coexistence preemption communication may be, for example, LTE-NR coexistence uplink preemption communication in which the eNB uses the same frequency band as that of the gNB in uplink communication. from UE. Alternatively, LTE-NR coexistence preemption communication may be, for example, downlink LTE-NR coexistence preemption communication in which the eNB uses the same frequency band as that of the gNB in communication. downlink to the UE.

[0624] The use of the above methods creates the following problem. In particular, no method has been disclosed for preemptive communication in LTE-NR coexistence. This causes problems in that a proper procedure for LTE-NR coexistence preemption communication cannot be performed and communication with low latency and high reliability is achieved.

[0625] Troubleshooting is disclosed below.

[0626] The UE performs an uplink preemptive transmission to a base station that performs preemptive communication (hereinafter, may be referred to as a preemptive base station). The preemptive base station may notify information indicating the occurrence of preemption to the base station that is interrupted by preemption communication (hereinafter, may be referred to as preemptive base station). Since this allows, for example, a preempted base station to perform a decoding process on data other than data received with a timing corresponding to preemptive communication, reliability in communication between the preempted base station and the UE can be improved.

[0627] Information indicating the occurrence of preemption may include information about the resources by which the preemption occurred. The information may be timing information such as subframe number, slot number, mini-slot number, or symbol number. The information may include information about the number of mini-slots or information about the number of symbols. The information may include information about frequencies, such as information about frequency resources that are used in preemptive transmission. The information may include, for example, power information. The preempted base station can separate the preemptive communication from the interrupted communication using the power information. The separation may be performed, for example, when the push-out communication and the interrupted communication are very different in power. This allows, for example, the base station to be preempted to receive both the preemptive communication and the interrupted communication.

[0628] The preemptive base station may notify the UE with LTE-NR coexistence of the uplink permission. The preemptive base station may perform notification, for example, while the UE is receiving a downlink signal from the preemptive base station. Since this, for example, eliminates the need for the UE to switch the downlink reception scheme between LTE and NR on uplink reception, the latency in uplink preemption transmission can be reduced.

[0629] As an alternative method, the preemptive base station may notify the preempted base station of the uplink grant information for the UE. The preempted base station may stop receiving the uplink from the UE with the uplink grant information. This creates, for example, the same advantages as previously described.

[0630] As an alternative method, the preemptive base station may notify, via the preempted base station, the UE of the uplink grant information for the UE. The preemptive base station may notify via the preempted base station, for example, while the UE is receiving a downlink signal from the preempted base station. The uplink grant may include information indicating the preemptive base station as the recipient of the uplink transmission. The information may be, for example, an identifier indicating a master base station or a secondary base station, a base station ID, or a cell ID of the recipient of the transmission. Notification from the preemptive base station to the preempted base station may be made through an interface between base stations (eg, an Xn interface). The preempted base station may stop receiving the uplink from the UE with the uplink grant information. Since this, for example, eliminates the need for the UE to switch the downlink reception scheme between LTE and NR upon receiving the uplink grant, the latency in uplink preemption transmission can be reduced.

[0631] The preempted base station may stop receiving the uplink from the UE with the timing of the occurrence of the preemptive transmission indicated by the uplink grant.

[0632] The UE may transmit to the preemptive base station an SR for the preemptive base station via the preempted base station. The SR may include information indicating that a scheduling request is being made to the preemptive base station. The information may be, for example, an identifier indicating a primary base station or a secondary base station, a base station ID, or a cell ID of the recipient of the transmission. The preempted base station may notify the preemptive base station of information indicating the reception of an SR for the preemptive base station. Notification from the preempted base station to the preemptive base station may be performed via an interface between base stations (eg, an Xn interface). Since this, for example, eliminates the need for the UE to switch the uplink transmission scheme between LTE and NR according to the SR transmission, the latency in the uplink preemption transmission can be reduced.

[0633] As an alternative example of including in the SR to be transmitted from the UE to the preempted base station information indicating that a scheduling request is being made to the preempting base station, the sequence of the SR can be made different depending on which entity is being executed. planning request. For example, the exponent of the root of the sequence, the amount of cyclic shift, or both can be made different. The preempted base station may determine to which entity the scheduling request is made using the SR sequence. This may, for example, reduce the amount of SR information.

[0634] As an alternative example, the sequence for a DMRS associated with a PUCCH that includes an SR can be made different depending on which entity the scheduling request is being made to. The preempted base station may determine to which entity the scheduling request is made using the sequence for the DMRS. This may, for example, reduce the amount of SR information as described previously.

[0635] The preemptive base station may configure an SR to be transmitted by its own base station to the UE. The preemptive base station may configure the UE directly or through the preempted base station.

[0636] The preempted base station may configure for the UE an SR to be transmitted to the preemptive base station via its own base station. The SR configuration may include, for example, SR transmission period and offset configuration, SR maximum retransmission number configuration, or SR frequency resource configuration. The SR configuration may include a sequence configuration to be used to transmit the SR. The sequence configuration may be, for example, a root exponent configuration or a cyclic shift configuration. The SR configuration may include sequence information for a DMRS associated with a PUCCH including the SR.

[0637] The configuration of the SR that the UE transmits to the preemptive base station may be the same or different from the configuration of the SR that the UE transmits to the preemptive base station via the preemptive base station. The configurations may be partly the same.

[0638] The configuration of the SR that the UE transmits to the preemptive base station via the preempted base station must be at least partially made different from the configuration of the SR that the UE transmits to the preempted base station. For example, the cyclic shifts of the sequences to be used to transmit an SR can be made different. As an alternative example, the sequences to be used for a DMRS associated with a PUCCH that includes an SR can be made different. This allows, for example, the base station to be preempted to determine whether the SR is respectively an SR addressed to its own base station or an SR addressed to the preemptive base station via its own base station. As a result, misoperation in the preempted UE can be prevented.

[0639] The preemptive base station may request the preempted base station to configure the SR that the UE transmits to the preemptive base station via the preempted base station. The request may include, for example, SR configuration information. The preempted base station may configure the SR for the UE with the information.

[0640] The SR configuration request may, for example, be included in signaling at an interface between base stations (eg, an Xn interface). The signaling may be, for example, secondary base station modification request signaling (SN Modification Request), secondary base station addition request (SN Add Request), or secondary base station modification confirmation of the secondary base station (SN Modification Confirmation). Three signaling may be used, for example, when the preemptive base station is the main base station. As an alternative example, the signaling may be notification of a secondary base station modification request handshake (SN Modify Request Handshake), a secondary base station add request handshake (SN Add Request Handshake), or a required secondary base station modification (Required SN Modification) . Three signaling may be used, for example, when the preemptive base station is a secondary base station. The signaling may be a different signaling or a new signaling may be provided.

[0641] The preemptive base station may configure, for the UE, an SR to be transmitted to its own base station via the preempted base station. The information included in the SR configuration may be as previously described. The preemptive base station may request the preempted base station for configuration information of an SR to be transmitted to its own base station by the preempted base station. The preempted base station may notify the preemptive base station of the information. The information may be SR configuration information, for example. As an alternative example, the information may include information about an SR that has already been assigned to the preempted base station. The information notified by the preempted base station may be used to configure the SR to be transmitted from the preemptive base station to the UE. This may, for example, prevent an overlap between an SR configuration and an SR configuration that has already been assigned to the preempted base station. Therefore, interference in the base station to be displaced can be reduced and misoperation can be prevented.

[0642] The preemptive base station may configure, via RRC signaling for the UE, an SR to be transmitted to its own base station via the preempted base station. For example, the signaling for RRC connection reconfiguration from the preemptive base station to the UE may include SR configuration information. This may, for example, reduce the amount of signaling from the preemptive base station to the UE. As an alternative example, the signaling may be MAC signaling or L1/L2 signaling. This allows, for example, a preemptive base station to quickly configure an SR for the UE.

[0643] The preemptive base station may request from the preempted base station configuration information of an SR to be transmitted to its own base station via the preempted base station, via an interface between base stations, for example, using Xn interface signaling. The signaling may be the same signaling through which the preemptive base station requests the preempted base station to configure an SR that the UE transmits to the preemptive base station via the preempted base station.

[0644] The preempted base station may notify the preemptive base station of the SR configuration information via an interface between base stations, for example, using Xn interface signaling. The signaling may be, for example, notification of a secondary base station modification request handshake (SN Modify Request Handshake), a secondary base station add request handshake (SN Add Request Handshake), or a required secondary base station modification (Required SN Modification). Three signaling may be used, for example, when the preemptive base station is the main base station. As an alternative example, the signaling may be a modification confirmation of the secondary base station (Modify Acknowledgment SN). The signaling may be used, for example, when the preemptive base station is a secondary base station. The signaling may be a different signaling or may be a newly provided signaling.

[0645] Combinations of SR configurations may be used. For example, the preemptive base station may configure for the UE both an SR to be transmitted directly to its own base station and an SR to be transmitted to its own base station via the preempted base station. The preemptive base station may configure via the same signaling or via different signaling. As an alternative example, the preemptive base station may configure, for the UE, the SR to be transmitted directly to its own base station, while the preempted base station may configure, for the UE, the SR to be transmitted to the preemptive base station via its own base station. station.

[0646] The UE may transmit the SR to one of the preemptive base station and the preempted base station. The UE may transmit an SR to, for example, a base station with an earlier possible transmission timing in the UE. This allows, for example, the UE to quickly transmit the SR with less processing. As an alternative example, the UE may transmit an SR to a base station to which the SR addressed to the preemptive base station arrives earlier. The UE may transmit an SR to a base station to which the SR addressed to the preemptive base station arrives earlier based on, for example, the latency at the interface between the base stations as a judgment criterion. The UE may be notified in advance of the latency. Therefore, the preemptive base station can quickly receive the SR.

[0647] The UE may transmit the SR to both the preemptive base station and the preempted base station. This may, for example, improve the reliability of the SR transmission. For example, retransmission prohibit timers may be dedicatedly provided for direct transmission of the SR to the preemptive base station and for transmission of the SR via the preempted base station. This may, for example, avoid the complexity of managing the SR. As an alternative example, the SR retransmission prohibit timer may be shared between direct transmission of the SR by the preemptive base station and transmission of the SR via the preempted base station. The UE may only be able to transmit the SR once to the base station to the base station for which the SR prohibit timer has been started and to which the SR is not transmitted.

[0648] Information about the allocation, between base stations, timing for receiving the uplink signal from the UE need not be used when configuring the SR, for example, configuring the timing of the SR. The UE does not need to transmit the SR to the preemptive base station and/or the preempted base station with SR transmission timing. In other words, the UE may transmit the SR to each of the base stations with a timing corresponding to the transmission timing of the SR if the timings for receiving the uplink signal from the UE are allocated to the base stations. For example, when timings for receiving an uplink signal from a UE are allocated to a preemptive base station, the UE does not need to transmit the SR of the preempted base station with the transmission timing of the SR. This may, for example, avoid the complexity of configuring an SR in the coexistence of LTE-NR.

[0649] As an alternative example, base station timing information for receiving an uplink signal from a UE may be used in SR configuration. For example, the transmission timing of the SR at the UE may be configured among the timings obtained by allocating timings for receiving the uplink signal from the UE to the base stations to which the SR is to be transmitted. As an alternative example, the timings for receiving the uplink signal from the UE at the base stations to which the SR is to be transmitted may be configured using the SR transmission timing configuration at the UE. For example, since the timings for receiving an uplink signal from the UE are allocated to the base stations to which the SR is to be transmitted by the transmission timing of the SR, the UE can quickly transmit the SR.

[0650] Multiple configurations of the SR to be transmitted from the UE to each base station may be provided. For example, both subframe offset pattern 0 with a period of 5 milliseconds and subframe offset pattern 2 with a period of 5 milliseconds can be used for the SR addressed from the UE to the preemptive base station. This may, for example, increase flexibility in configuring the SR.

[0651] An SR configuration may be applied to a configuration on a different UCI. For example, a method for configuring an SR can be applied to a CSI configuration. Therefore, for example, the transmission of another UCI may create the same benefits as those of the transmission of an SR.

[0652] Preemption may be applied to the SR to be transmitted from the UE to the preemptive base station. For example, the UE may stop transmitting the uplink to the preempted base station and transmit an SR to the preemptive base station. The UE may or may not need to resume uplink transmission to the preempted base station after transmitting the SR. This allows, for example, the UE to quickly notify the SR.

[0653] The UE may transmit the SR with the configuration of the SR to be transmitted to the preemptive base station. In other words, the UE may transmit the SR with the SR transmission timing information included in the configuration (eg, SR transmission period or SR transmission offset).

[0654] The preempted base station does not need to allocate the uplink transmission from the UE to its own base station with the transmission timing of the SR to be transmitted from the UE to the preemptive base station. The uplink transmission may be a transmission of, for example, PUSCH, DMRS, PUCCH, SRS, or other uplink signals. The preemptive base station may notify the preempted base station of the configuration information of the SR to be transmitted from the UE to its own base station. The preempted base station may determine or change, by notification, the timing of the uplink transmission from the UE to its own base station.

[0655] As an alternative example, the preemptive base station may exclude the timing with which the SR can be transmitted from the UE to its own base station from the timing with which the UE performs uplink transmission to the preempted base station to configure the timing binding. The uplink transmission may be a transmission of, for example, DMRS, SRS, or other uplink signals. The preemptive base station may be aware of the timing information with which the uplink transmission occurs from the preempted base station. The preempted base station may notify the preemptive base station of the information. In response to the notification, the preemptive base station may notify the configuration information of the SR to be transmitted from the UE to its own base station. The timing with which the SR may be transmitted from the UE to its own base station may be excluded from the timing with which the UE performs uplink transmission to the preempted base station to configure the timing.

[0656] The preemptive base station may notify the preempted base station of timing information with which uplink preemption transmission can occur. The information may be identical to, for example, the information described in the third embodiment. The preempted base station may stop receiving the uplink from the UE with a time reference. This can, for example, reduce latency in uplink preemption transmission.

[0657] The UE may notify the preemptive base station of information indicating that a preemptive transmission has occurred. The information may be, for example, a predefined code. The code may be identical to that described in the first modification of the third embodiment. The UE may notify the preemptive base station of the information immediately after the preemptive data transmission has occurred. This may, for example, reduce latency in an uplink preemptive transmission.

[0658] The UE may notify the preemptive base station of the information via the preempted base station. The UE may perform notification via the preempted base station, for example, while the UE is transmitting an uplink signal to the preempted base station. Notification from the preempted base station to the preemptive base station may be made via an interface between base stations (eg, an Xn interface). Since this, for example, eliminates the need for the UE to switch the uplink transmission scheme between LTE and NR according to the transmission of the SR, the latency of the uplink preemption transmission can be reduced.

[0659] Another solution is described. In connection with downlink preemption, the preemptive base station may notify the preempted base station of information indicating that a preemptive transmission will occur. The information may include, for example, timing information with which downlink preemption will occur, or scheduling information for downlink preemption communication. The preempted base station may stop the downlink transmission with the timing of the preemptive transmission. This may, for example, reduce interference due to downlink preemption.

[0660] The preempted base station may notify the UE of information indicating that a preemptive transmission will occur. The preempted base station may notify before or after the preemptive base station notifies the preempted base station. In response to the notification, the UE may switch the downlink reception scheme between LTE and NR. This may, for example, reduce latency due to downlink preemption.

[0661] For example, a predefined code may be used in a notification to the UE. The code may be identical to that described in the first modification of the third embodiment. Upon receiving the code, the UE may switch the downlink reception scheme between LTE and NR. This may, for example, further reduce latency due to downlink preemption.

[0662] The preemptive base station may be aware in advance of the preemptive timing or the non-preemptive timing of the preempted base station.

[0663] The preempted base station may notify the preemptive base station in advance of timing information with which timing communication is possible. The preempted base station may perform notification, for example, after or in the absence of the above request. The information may be timing information with which preemptive association is possible. The time base with which preemptive communication is possible may be the time base with which the preempted base station transmits, for example, a synchronization signal, broadcast information, or PDCCH. The preemptive base station may or may not need to perform preemptive communication with the information. For example, the preemptive base station may perform a preemptive transmission with a time reference from which preemption is possible.

[0664] The timing information with which preemption communication is possible or not possible may include, for example, information about a subframe with a possible preemption or a subframe without a possible preemption, information about the period with which the subframe is repeated, or information about the duration timing with possible preemption or timing without possible preemption. A subframe without possible preemption may be, for example, a subframe in which a burst of SS pulses (synchronization signal) in NR is to be transmitted, or another subframe. A subframe may be a radio frame, a slot, a mini-slot, or a symbol. The information may be a combination of many pieces of information. As an alternative example, the notification of the information may be implemented as a bitmap indicating characters with preemption or non-preemption characters. The symbols may be subframes, slots, mini-slots, or another unit of time. Notification of the information may be carried out periodically or aperiodically. The information may include duration information depending on the information. This may, for example, increase flexibility in configuring preemptive timing or non-preemptive timing.

[0665] Another solution is described. In connection with downlink preemption, the preemptive base station may notify the UE of information indicating the occurrence of a preemptive transmission. The information may include, for example, timing information with which downlink preemption has occurred, or scheduling information of downlink preemption communication that has occurred. The preemptive base station may provide this notification to the UE through the preempted base station. In response to the notification, the UE may extract data for preemptive communication from the received downlink signal. For example, a method for correcting a DC component offset between LTE and NR can be used as an extraction method. This may, for example, reduce the amount of signaling between the base station and the UE to preemptive communication.

[0666] The plurality of solutions disclosed in the first modification may be combined. For example, the preemptive base station may notify the preempted base station of information indicating that a preemptive transmission will occur. In response to the information, the preempted base station may stop downlink transmission with preemption timing. The preemptive base station may notify the UE of information indicating the occurrence of a preemptive transmission. In response to the notification, the UE may extract data for preemptive communication from the received downlink signal. This may, for example, reduce the amount of signaling between the base station and the UE before the pre-population communication, and interference with the downlink pre-emption communication.

[0667] The first modification provides preemptive communication with coexistence of LTE-NR. This provides low latency and high reliability communications with LTE-NR coexistence.

[0668] The second modification of the fourth embodiment

The coexistence of LTE-NR has the following problem. Specifically, when the timing of the PUCCH and/or SRS transmission from the UE to the NR base station competes with the timing of the PUCCH and/or SRS transmission from the UE to the LTE base station, the contention resolution processing is not defined in the communication system. Therefore, the system may not work properly.

[0669] The method to be described later in the first modification of the fifth embodiment can be applied as a solution to the problem.

[0670] For example, the example to be described later in FIG. 41. The UE may transmit in the same subframe the PUCCHs to be transmitted to the LTE base station and the NR base station.

[0671] The second modification may prevent misoperation caused by PUCCH and/or SRS contention between LTE and NR.

[0672] Fifth embodiment

In DC for LTE and NR, the UE may switch between single TX, in which one transmitter switches between LTE and NR to perform transmission, and dual TX, in which respective LTE and NR transmitters are used. Single TX and dual TX may be switched, for example, when DC is configured and/or upon handover.

[0673] The main base station may determine the switch between single TX and dual TX and notify the UE of it. The main base station may perform the determination using the maximum sensitivity degradation (MSD), which is the maximum amount of desensitization that is caused by the effect of the uplink transmission of one of the carriers on the downlink reception of the other carrier.

[0674] The following describes an exemplary sequence for switching between single TX and dual TX in DC for LTE and NR.

[0675] The UE notifies the base station of compatible carrier combination information. The combinations may be included in the UE capabilities. The combinations may be, for example, combinations of carriers that fulfill the MSD conditions that are defined in the standard. The main base station obtains using the MSD carrier combination information in the combinations.

[0676] The UE notifies the base station of the measurement result of the carrier signal. The master base station may determine the carriers to be used in the CA and/or DC. The main base station also determines whether the UE is using single TX or dual TX. The master base station makes the determination using the MSD value. For example, the main base station may determine, as the carriers to be used in the CA and/or DC, a combination of carriers with high reception sensitivity considering MSD. As an alternative example, the main base station may determine the use of a single TX when the MSD value of the combination of carriers to be used is greater than or equal to a predetermined threshold value or greater than a predetermined value. When defined, the main base station can receive the MSD in combination of carriers from the standard.

[0677] The main base station notifies the UE of information about carriers to be used and/or information indicating whether the UE is using single TX or dual TX. The main base station may notify via dedicated RRC signaling, such as signaling for RRC connection reconfiguration.

[0678] The application of the above method creates the following problem. In particular, information indicating whether two transmitters in the UE are allowed to simultaneously transmit does not reflect the actual capabilities of the UE. This leads to the problem of inefficient communication in the communication system.

[0679] A solution to the problem is disclosed. The UE desensitization (SD) is used when carriers to be used in the CA and/or DC are determined and/or switching between single TX and dual TX is determined. The master base station can switch between single TX and dual TX using the SD information. The switching may be, for example, a semi-static switching. The semi-static handover may be, for example, handover via RRC signaling.

[0680] SD may be a value measured in advance. For example, the SD may be SD measured in transit or SD measured during operation. The SD measured during operation may be, for example, the SD measured during calibration.

[0681] The following items (1) to (8) are disclosed as examples of pieces of information to be used when the main base station determines the switch between single TX and dual TX.

[0682] (1) SD information;

[0683] (2) information about whether double TX is allowed;

[0684] (3) MSD information;

[0685] (4) information about whether single TX is allowed;

[0686] (5) UE transmit power information;

[0687] (6) information indicating that a portion of the carrier bands of the gNB is in use;

[0688] (7) frame timing information; And

[0689] (8) a combination of items (1) to (7) above.

[0690] The information in paragraph (1) may be provided per carrier combination. This allows, for example, the base station to select the combination of carriers to be used with less degradation in sensitivity. Alternatively, SD information may be provided per band combination. This may, for example, reduce the amount of information about the SD.

[0691] The information in paragraph (1) may be, for example, essentially the value of SD. As an alternative example, the SD information may be information obtained by classifying SD values. The classified information may be values classified by the same width, such as a 1dB width, or pieces of information classified by different widths.

[0692] The information in clause (2) may include information about carrier combinations that do not allow dual TX. The information may include information about the reason why double TX is not allowed. The reason may be, for example, the amount of desensitization beyond the MSD, or the physical limitations of the UE (eg, the number of transmitters corresponds to only one).

[0693] The information in clause (3) may include, for example, information about carrier combinations with SD outside the MSD at the UE. This allows, for example, the main base station to select a carrier combination at DC start when there is no carrier combination whose SD of the UE is lower than or equal to MSD despite the requirements of high capacity communication using dual TX.

[0694] The information in paragraph (4) may include information about the reason why a single TX is not allowed. Examples of the cause may include the fact that the UE cannot switch between LTE and NR within a certain time. This may, for example, speed up the operation of the base station and the UE when a single TX cannot be allowed. For example, the main base station can quickly determine DC cancellation when there is no carrier combination that can be supported by the main base station and the secondary base station, and whose SD falls below the MSD.

[0695] The information in item (5) may be a transmission power per carrier. The information may include information about the maximum transmit power of the UE. With the help of the information, the master base station can determine the carriers in use and/or determine the switch between single TX and dual TX. This allows, for example, the main base station to select the optimal combination of carriers in the communication system in view of reducing the degradation in sensitivity at the receiver when the transmission power of the UE is low.

[0696] The information in clause (6) may include, for example, part bandwidth (BWP) information. The main base station may, for example, extract the MSD and/or SD in the BWP using the information. The master base station may determine the carriers in use and/or determine the switch between single TX and dual TX using the extracted MSD and/or SD. This allows, for example, the main base station to select the optimal combination of carriers in the communication system, taking into account the bandwidth that the UE actually uses for transmission and reception.

[0697] The information in item (7) may include information about the frame timing difference between the main base station and the secondary base station. The main base station can determine whether to switch to a single TX using the information. This allows, for example, the UE to avoid degradation of communication efficiency due to contention between signals in LTE and NR when the main base station switches to single TX.

[0698] The pieces of information in paragraphs (1) through (8) may be included in the capabilities of the UE. For example, this eliminates the need for the base station to re-generate signaling upon receipt of information, which therefore facilitates control at the base station. As an alternative example, the fragments in paragraphs (1) to (8) need not be included in the UE capabilities. Two of the combinations may be used. For example, items (1) to (5) may be included in UE capabilities, but items (6) and (7) need not be included in UE capabilities. For example, the UE may notify the main base station of the information in item (7) as a measurement result notification. This provides a communication system, for example, flexible operation, which adapts to time-varying information.

[0699] The base station may request some or all of the pieces of information from the UE in steps (1) through (8). The UE may notify the base station of some or all of the pieces of information in items (1) to (8). The request and/or notification may be performed via RRC signaling. The request can be made through, for example, UE CapabilityEnquiry (UECapabilityEnquiry) signaling or other RRC signaling. The notification may be through, for example, UE capability information (UECapabilityInformation) signaling or other RRC signaling.

[0700] The base station may request from the high-level NW device some or all of the pieces of information in paragraphs (1) to (8). The higher level NW device may receive information from the UE in advance or from another base station. The other base station may be, for example, the base station with which the UE was connected prior to the handover. The high-level NW device can be AMF, SMF, or MME. The higher-level NW device may notify the base station of some or all of the pieces of information in steps (1) to (8). The request and/or notification may be performed, for example, upon the occurrence of mobility in the UE. The request and/or notification may be made through the interface between the higher level NW device and the base station. This may, for example, reduce the amount of signaling over the air interface in the handover of the UE, for example, the Uu interface.

[0701] The base station may simultaneously receive some or all of the pieces of information in paragraphs (1) to (8) for all combinations of carriers that the UE can use. This may, for example, reduce the amount of signaling over the air interface when the UE starts DC.

[0702] As an alternative example, the base station may receive some or all of the pieces of information in paragraphs (1) through (8) for a portion of the carrier combinations that the UE may use. For example, the base station may receive some or all of the pieces of information in items (1) to (8) for carrier combinations, the measurements of which the UE receives from the surrounding base stations. The base station may receive information, for example, in sequence for the start of the DC. This may, for example, reduce the amount of signaling when the UE attaches to the base station, which therefore allows the UE to quickly attach to the base station.

[0703] The high-level NW device may request some or all of the pieces of information in steps (1) through (8) from the base station. The request may be made as a UE capability request, for example. The request may be made, for example, in sequence when the UE attaches to the base station. The request can be made through the interface between the higher level NW device and the base station. The request may be made via signaling at the interface, for example, using a UE radio capability negotiation request.

[0704] The base station may request some or all of the pieces of information from the UE in steps (1) through (8). The base station may make a request after a request from the higher level NW devices at the base station or at the beginning of the DC.

[0705] The UE may notify the base station of some or all of the pieces of information in item (1) to (8). The UE may perform notification upon request from the base station to the UE. The notification may be implemented as a UE capability notification.

[0706] The UE may simultaneously notify some or all of the pieces of information in paragraphs (1) through (8) for all carrier combinations that its own UE may use. This may, for example, reduce the amount of signaling over the air interface when the UE starts DC. As an alternative example, the UE may notify its own UE information for a portion of the carrier combinations that its own UE may use. Part of the combinations may be, for example, combinations that are requested by the base station. This may, for example, reduce the amount of signaling when the UE attaches to the base station, which therefore allows the UE to quickly attach to the base station.

[0707] The base station may notify the high-level NW device of some or all of the pieces of information in steps (1) to (8). The notification may be implemented as a UE capability notification. The notification may be made as a response to a request from the higher level NW device to the base station. The response can be made through the interface between the higher level NW device and the base station. The response may be via signaling at the interface, for example, using a UE Radio Capability Negotiation Response (UE Radio Capability Negotiation Response) or UE capability information notification (UE Capability Information Indication).

[0708] The base station determines the carrier combinations to be used in the CA and/or DC. The base station may determine whether the UE is using single TX or dual TX. The base station may perform the determination using the result measured by the UE and received by the base station from the UE. Some or all of the pieces of information in paragraphs (1) through (8) may be used. The base station may be the main base station in the DC. The base station may determine a plurality of carriers that its own base station may use. The base station may determine the plurality of carriers that the secondary base station may use.

[0709] The base station may notify the secondary base station of the configuration of the used carrier in connection with the UE. The notification may include a configuration indicating which one of the single TX and dual TX is being used in connection with the UE. The base station may perform notification via an interface between base stations. The notification may be included in, for example, a request to add a secondary base station (Request to Add SN), a request to modify the secondary base station (Request to Modify SN), or a notification of completion of reconfiguration of the secondary base station (Complete SN Reconfiguration). The signaling for the interface between base stations may be newly provided for notification.

[0710] The notification may include some or all of the pieces of information in paragraphs (1) to (8), for example, information about the SD of the UE. The SD information may be SD for all carrier combinations that may be supported by the UE. The secondary base station may store information about the SD. For example, only a one-time notification of information from the base station to the secondary base station will be sufficient. Thus, the amount of signaling can be reduced. Alternatively, the SD information may be SD for a portion of the carrier combinations that may be supported by the UE. A part of the combinations may be, for example, a combination of carriers to be used in a DC configuration. This can reduce the amount of signaling when configuring the DC.

[0711] The secondary base station may notify the base station of the configuration response. The response may be included in, for example, a notification of a response to a request to add a secondary base station (Request to Add SN) or a notification of a response to a request to modify a secondary base station (Request to Modify SN). The signaling for the interface between base stations may be newly provided for notification of the response.

[0712] The base station may notify the UE of the used carrier configuration in communication between the base station and/or the secondary base station. The notification may include a configuration indicating which one of the single TX and dual TX the UE is using. The base station may notify the configuration via RRC signaling. The base station may notify, for example, via RRC signaling to reconfigure the RRC connection. The base station may advertise the configuration, for example, as a sequence for starting the DC.

[0713] The base station may notify the UE of the configuration via MAC signaling. This can, for example, speed up switching between single TX and dual TX.

[0714] As an example, when the base station notifies the UE of the configuration via MAC signaling, the base station may switch to single TX with notification when its own base station and/or secondary base station activates SCell. Such switching may be applied, for example, when the value of SD and/or MSD is higher in the combination of the SCell and the cell that is used between the base station and the UE. The base station may transmit the configuration notification at the same time as the MA signaling to issue the SCell activation/deactivation instruction, or as the same signaling as the MAC signaling. This allows, for example, the base station to select the highest quality cell under SCell control.

[0715] Alternatively, the base station may notify the UE of the configuration via L1/L2 signaling. This provides faster notification.

[0716] The UE may configure single TX/dual TX. Switching can be performed after the base station performs the configuration.

[0717] FIG. 39 is an exemplary sequence diagram illustrating a procedure when a main base station issues a single TX/double TX instruction to the UE. Fig. 39 illustrates an example when DC starts. Example Fig. 39 illustrates the case where the main base station is a MeNB and the secondary base station is an SgNB. Example Fig. 39 illustrates the case where the main base station determines the single TX/double TX with the SD information.

[0718] At Step ST5010 of FIG. 39 The MeNB transmits a downlink measurement signal to the UE. In Step ST5011, the SgNB transmits a downlink measurement signal to the UE. The UE receives the Stage signal ST5010 and/or ST5011 and measures the downlink signal. In Step ST5012, the UE notifies the MeNB of the downlink measurement result.

[0719] At Step ST5015 of FIG. 39 The MeNB requests UE capabilities from the UE. The request may include information about the combination of carriers measured by the UE. In Step ST5016, the UE notifies the MeNB of the UE's capabilities. The notification may include information about the SD in the combination of carriers.

[0720] At Step ST5017 of FIG. 39 The MeNB accesses and determines the usable carriers in the DC. The carriers used may be a combination of carriers that the MeNB may use, a combination of carriers that the SgNB may use, or both. In Step ST5018, the MeNB evaluates and determines which one of the single TX and dual TX is used by the UE.

[0721] At Step ST5020 of FIG. 39 The MeNB issues a request to add a secondary base station to the SgNB. The request may include information about the used carriers, which are determined in Step ST5017. The request may include information indicating which one of the single TX or dual TX is used, which is determined in Step ST5018. In Step ST5021, the SgNB notifies the MeNB of the response to Step ST5020. Fig. 39 illustrates an example providing acknowledgment to Step ST5020.

[0722] At Step ST5025 of FIG. 39 The MeNB configures the DC for the UE. The configuration may be performed, for example, via RRC connection reconfiguration signaling. The configuration includes information about the carriers to be used, which are determined in Step ST5017. The configuration also includes information indicating which one of the single TX and dual TX is used, which is determined in Step ST5018. The UE starts DC configuration in Step ST5025.

[0723] At Step ST5026 of FIG. 39, the UE performs a random access procedure with the MeNB. Step ST5026 may be performed, for example, when the used carriers in the MeNB have changed.

[0724] At Step ST5027 of FIG. 39 The UE notifies the MeNB of the completion of the DC configuration. In Step ST5028, the MeNB notifies the SgNB of the completion of the reconfiguration of the secondary base station. In Step ST5029, the UE performs a random access procedure with the SgNB.

[0725] Although FIG. 39 illustrates an example where Step ST5017 is executed before Step ST5020, Step ST5017 may be executed after Step ST5021. The same may be true for Stage ST5018. Since this allows, for example, the SgNB to determine the carriers in use by excluding carriers that the SgNB cannot use, the MeNB does not need to re-determine the carriers in use.

[0726] In FIG. 39 The MeNB may notify the SgNB of the SD information of the UE. Since this allows, for example, the SgNB to select the highest quality cell when selecting the SCell to be used in the CA, the link quality in the SgNB can be improved.

[0727] The main base station may notify the secondary base station of the SCell information that its own main base station has activated or deactivated. The notification may include information about the UE's SD. The notification may be made through an interface between base stations (eg, an Xn interface). The secondary base station can control the SCell to be used by its own secondary base station with the information. Therefore, for example, the secondary base station can use the SCell with high quality even after the SCell to be used by the main base station changes. This can increase the communication capacity and ensure reliability.

[0728] The method can be applied when the main base station and the secondary base station are swapped. In other words, the secondary base station may notify the main base station of the SCell information activated or deactivated by its own secondary base station. The notification may include information about the UE's SD. This creates the same benefits as those provided by the main base station.

[0729] FIG. 40 is a sequence diagram illustrating the SCell information notification when the SCell is activated/deactivated. Fig. 40 illustrates an example when the MeNB activates/deactivates the SCell of its own eNB.

[0730] In Step ST5101 of FIG. 40 MeNB determines whether to activate or deactivate the SCell. The MeNB may perform the determination, for example, using the measurement result of the SCell that the UE notifies in advance.

[0731] At Step ST5102 of FIG. 40 The MeNB notifies the UE of SCell activation. The MeNB may notify deactivation. The MeNB may notify via MAC signaling. In Step ST5103, the UE may perform a random access procedure with the MeNB using the SCell.

[0732] In Step ST5104 of FIG. 40 The MeNB notifies the SgNB of the activated/deactivated SCell information. The information may be, for example, the carrier number of the SCell. In Step ST5104, the SgNB can manage the SCell in its own gNB.

[0733] Although FIG. 40 illustrates the case where the MeNB determines the activation/deactivation of the SCell, the same may be true for the SgNB. In other words, the SgNB may perform Step ST5101, perform Step ST5102 on the UE, perform Step ST5103 on the MeNB, and perform Step ST5104 with the UE. This creates the same benefits as those provided by the MeNB.

[0734] Although FIG. 40 illustrates an example when Step ST5104 is executed after Step ST5103, Step ST5104 may be executed before Step ST5103. This allows, for example, SgNB to quickly control SCell.

[0735] The fifth embodiment increases the efficiency of the DC communication system.

[0736] First modification of the fifth embodiment

When the UE uses a single TX in DC using an LTE base station and an NR base station, the following problem occurs. In other words, when the PUCCH and/or SRS transmission instruction from the NR base station conflicts with the PUCCH and/or SRS transmission instruction from the LTE base station, processing for resolving the conflict is not defined in the communication system. Therefore, the communication system may not work properly.

[0737] The solution to the problem is disclosed below.

[0738] A short PUCCH using resources short in the time direction and long in the frequency direction is used as a PUCCH in NR. The short PUCCH in NR is multiplexed with the PUCCH in LTE. The PUCCH in LTE may be punctured during multiplexing. The symbols to be punctured in the PUCCH in LTE may be the symbols that are occupied by the short PUCCH in NR. Symbols equivalent to the time it takes the UE to switch between LTE and NR may be punctured.

[0739] The UE may include information indicating the occurrence of PUCCH in LTE and NR in the same subframe, in PUCCH in NR or PUCCH in LTE. The information may be included as, for example, the UCI. The gNB can understand the occurrence of PUCCH in the same subframe from the information. The same may be true for eNBs. This allows, for example, the eNB and/or gNB to seamlessly schedule an uplink PUCCH transmission.

[0740] FIG. 41 illustrates an exemplary PUCCH transmission in LTE and NR in the same single TX subframe. On FIG. 41, the horizontal axis represents one subframe, and the vertical axis represents the frequency resources with which the UE can perform uplink transmission.

[0741] In FIG. 41, the UE transmits a PUCCH in LTE to the eNB using frequency/time resources 5501. The UE switches the transmitter between LTE and NR in time slot 5502. The UE transmits a short PUCCH in NR to the gNB using frequency/time resources 5503.

[0742] Although FIG. 41 exemplifies the use of the same frequencies in NR and LTE, the frequencies may differ between NR and LTE.

[0743] The UE may transmit PUSCH in LTE. The UE may transmit the PUSCH in LTE in a symbol to transmit the PUCCH in LTE. For example, the UE may transmit a PUSCH in LTE with the same timing as that of a PUCCH in LTE using a different subcarrier than that of a PUCCH in LTE. This can increase the transmission rate for a single TX.

[0744] The above description can be applied to contention between PUCCH in LTE and SRS in NR. For example, a short PUCCH in NR can be read as SRS in NR. This makes it possible, for example, to increase the efficiency of the communication system.

[0745] Priorities may be assigned to SRS in LTE and PUCCH in NR. The UE may transmit a high priority signal in a subframe. Priorities may be assigned, for example, when a short PUCCH is used in NR. For example, the priority for PUCCH may be set to NR. The priority for SRS in LTE can be set.

[0746] Alternatively, the UE may transmit SRS in LTE and PUCCH in NR in a time division manner. For example, the UE may transmit the SRS in LTE in a symbol before that of the PUCCH in NR. As an alternative example, the UE may send the PUCCH in NR in a symbol before that of the SRS in LTE.

[0747] Long PUCCH in NR can be used for connection between SRS in LTE and PUCCH in NR. For example, the UE may send PUCCH in NR to gNB using frequency/time resources 5501 in FIG. 41. The UE switches the transmitter between LTE and NR in timeslot 5502. The UE may transmit SRS in LTE to the eNB with frequency/time resources 5503.

[0748] Prioritization and/or time division transmission may be applied to SRS in LTE and SRS in NR.

[0749] Information about PUCCH and/or SRS transmission orders and/or priorities in LTE and NR may be predefined in the standard, in accordance with the first modification. Alternatively, the main base station may broadcast or in a dedicated manner notify the information of the UEs it serves. The main base station may notify via dedicated RRC signaling. The main base station may perform notification. This provides, for example, flexible control in the coexistence of LTE-NR.

[0750] According to the first modification, subframes in which transmission is possible in LTE and subframes in which transmission is possible in NR can be allocated in a time division manner. For example, subframes with odd subframe numbers may be allocated to LTE, and subframes with even subframe numbers may be allocated to NR. Subframes may be replaced by slots or mini-slots. Therefore, for example, even when the symbol lengths in LTE and NR are different, multiplexing in LTE and NR is possible.

[0751] According to the first modification, symbols capable of being transmitted in LTE and symbols capable of being transmitted in NR can be allocated in a time division manner. For example, the first half of the symbols in a subframe may be allocated by LTE, and the second half of the symbols in a subframe may be allocated by NR. This creates, for example, the same benefits as those described previously.

[0752] The first modification may avoid misoperation that is caused by PUCCH and/or SRS contention between LTE and NR.

[0753] The second modification of the fifth embodiment

Uplink preemption communication can be applied to a single TX. For example, upon occurrence of high priority uplink communication from UE to gNB during uplink communication from UE to eNB, the UE can perform uplink communication with the gNB by switching between LTE and NR.

[0754] The LTE-NR coexistence uplink preemptive communication method, which is disclosed in the first modification of the fourth embodiment, can be applied to the single TX uplink preemptive communication method. This may, for example, avoid the complexity of development in a communication system.

[0755] The second modification of the fifth embodiment enables fast execution of uplink preemptive communication with a single TX. Therefore, low latency communication is possible with a single TX.

[0756] Sixth embodiment

Supplemental Uplink (may be referred to as SUL hereinafter) for NR can be used to compensate for the difference in cell coverage between uplink and downlink at a high frequency in NR (eg, several tens of GHz). A frequency lower than that in NR can be used as SUL. The frequency may be, for example, equal to that in LTE. In a SUL transmission from a UE, the path loss can be measured with the downlink signal from the base station in LTE. This allows, for example, a path loss measurement in SUL using a signal in the same bandwidth as that of SUL, or at a frequency close to that of SUL.

[0757] The application of the above method creates the following problem. In particular, when path loss in SUL is measured with a downlink signal in the same band as that of SUL, the obtained path loss is inaccurate because the base station of the downlink signal differs from the transmission destination in SUL. Moreover, the path loss is very different between the high frequency band used in NR (eg several tens of GHz) and the band used in SUL (eg several GHz). Even when both pathlosses are corrected, the corrected pathloss may be inaccurate due to, for example, a difference in the presence or absence of an obstacle, or a difference in propagation mode. Thus, in SUL, there is a problem of inability to establish a link in SUL due to lack of uplink power, and a problem of increasing interference with other base stations due to excessive uplink power.

[0758] Problem solving is disclosed. gNB transmits a downlink signal to measure path loss. The UE measures the downlink path loss. The UE extracts the path loss in the SUL from the path loss.

[0759] The carrier may be newly assigned for the downlink signal to measure pathloss. The downlink signal bandwidth may be exactly the same as that in SUL. The downlink signal bandwidth may be, for example, the bandwidth to be used for the UE to communicate with the eNB. The frequency of the downlink signal can be made different from that in SUL. For example, when a bandwidth is used in FDD, the frequency of the downlink signal can be made different from that in SUL. Alternatively, the frequency of the downlink signal may be identical to that in SUL. For example, when a band is used in TDD, the frequency of the downlink signal may be identical to that in SUL. This may, for example, avoid the complexity of controlling the base station and the UE when measuring path loss.

[0760] Alternatively, a band other than that in SUL may be used for the downlink signal to measure path loss. For example, a band including the same frequency as that of SUL may be used in the downlink. Therefore, for example, the path loss in SUL can be obtained more accurately. As an alternative example, a band including a frequency other than that in SUL may be used in the downlink. As an alternative example, the frequency used by the gNB in the CA can be used. As an alternative example, the frequency may be one that is not used to transmit and receive user data to and from the gNB. This may, for example, prevent depletion of resources for transmitting and receiving user data to and from the gNB due to downlink signaling.

[0761] The gNB may use the SS as the downlink signal. For example, the gNB may transmit the downlink signal as an SS. The SS block may correspond to the portion of the beams that are covered by the gNB. A part of the beams may be, for example, beams directed towards UEs that are served by a gNB. This may, for example, reduce the transmit power of the gNB and interference with other UEs, such as UEs only connected to the eNB.

[0762] The gNB is not required to transmit the PBCH in the downlink signal. This may, for example, reduce interference with other UEs. Alternatively, the gNB may transmit the PBCH in the downlink signal. The UE may obtain, using the PBCH, the frame number (eg, SFN) to be used in the SUL. The UE may obtain downlink signal transmission power using the PBCH. The UE may extract the downlink signal path loss from the downlink signal transmission power received from the PBCH. Since this eliminates the need, for example, to provide other signaling on the downlink signal from the gNB to the UE, the amount of signaling over the air interface can be reduced.

[0763] The gNB may transmit a downlink signal in accordance with the SS burst format. Can be used to change the arrangement of signals in the pulse burst SS, which is described in the fourth embodiment. This allows, for example, multiplexing a non-MBSFN signal to be transmitted from an eNB with a downlink signal to be transmitted from a gNB.

[0764] As an alternative example, the gNB may sequentially transmit SS for the respective beams. For example, the gNB may transmit the SS for beam #2 immediately after transmitting the SS for beam #1. gNB may transmit SS intermittently. The transmission method may be in the form of, for example, serial transmission of SS for all beams, and then serial retransmission of SS for all beams after a predetermined interval.

[0765] As an alternative example, CSI-RS may be used as a downlink signal. For example, the gNB may send an aperiodic CSI-RS to the UE. The UE may measure the path loss using the CSI-RS. Since this eliminates the need, for example, for a gNB to always reserve frequency resources for downlink signal transmission, frequency resources can be saved.

[0766] The frame timing of the downlink signal can be adjusted, for example, to those of carriers in the NR band. This, for example, facilitates control in the base station. As an alternative example, the frame timing of the downlink signal may be adjusted to that of the carriers in the band used by the eNB in LTE. The UE, gNB, and eNB may apply the method described in, for example, the fourth embodiment to adjust the frame timing of the downlink signal to that of the carriers in the band used by the eNB. This may, for example, reduce interference between the downlink signal and non-MBSFN signals at the eNB. As an alternative example, the gNB may arbitrarily determine the frame timing of the downlink signal. The method can be applied, for example, when the bandwidth of the downlink signal is different from that of LTE. This can increase the flexibility of control by the gNB using the downlink signal.

[0767] The frame timing in SUL can be adjusted to, for example, that of carriers in the NR band. This, for example, facilitates control in the base station. As an alternative example, the frame timing in the SUL may be adjusted to that of the carriers in the band used by the UE to communicate with the eNB in LTE. The UE, gNB, and eNB may apply the methods described in, for example, the first modification of the fourth embodiment and/or the first modification of the fifth embodiment, to adjust the timing in the SUL to that of the carriers in the band used by the eNB. This creates the same advantages as those of, for example, the first modification of the fourth embodiment and/or the first modification of the fifth embodiment. As an alternative example, the frame timing in the SUL may be adjusted to that of the downlink signal. This may, for example, increase the flexibility of SUL management in the UE and/or gNB.

[0768] The symbol length in SUL may be identical to that used in the NR band. This, for example, facilitates scheduling in gNBs and/or UEs. As an alternative example, the symbol length in SUL can be made different from that used in the NR band. This provides, for example, flexible operation in SUL. As an alternative example, the symbol length in the SUL may be identical to that of the carriers in the band used by the UE to communicate with the eNB in LTE. This can, for example, facilitate handover control over uplink transmission between LTE and NR at the UE.

[0769] The gNB may notify the UE of the symbol length information in the SUL. The gNB may notify, for example, via dedicated RRC signaling. The gNB may include symbol length information in the SUL in signaling to notify the UE of configuring the use of the SUL. As an alternative example, the gNB may broadcast to the UEs it serves information about the symbol length in the SUL.

[0770] The gNB may instruct the UE to measure downlink path loss. The gNB may issue an instruction via RRC signaling, eg using RRC connection reconfiguration. The gNB may instruct the UE to measure the downlink signal path loss, eg, via signaling to change the UE's PSCell or PCell. PSCell or PCell may be changed, for example, after SUL is used. The gNB may instruct the UE to start using SUL. The gNB may issue an instruction, for example, when the downlink path loss in the used NR band exceeds a predetermined threshold. The UE may notify the gNB of information indicating that the downlink path loss in the used NR band exceeds a predetermined threshold. The threshold value may be defined in the standard, or the gNB or eNB notify the UE in advance. Notification can be done, for example, via signaling to reconfigure the RRC connection. As an alternative example, the gNB may issue an instruction, for example, when the uplink path loss in the used NR band exceeds a predetermined threshold. The threshold may be defined similarly to the threshold for downlink pathloss in the NR band.

[0771] As an alternative example, a gNB may issue an instruction via MAC signaling. For example, when the radio environment suddenly changes in the used NR band, the gNB can promptly instruct the UE to measure the downlink path loss. Therefore, the UE can quickly use SUL.

[0772] As an alternative example, the gNB may issue an instruction via L1/L2 signaling. Therefore, for example, the gNB can promptly instruct the UE to measure the downlink path loss. As a result, the UE can use SUL even faster.

[0773] As an alternative example, a gNB may issue an instruction through a combination of at least two of RRC signaling, MAC signaling, and L1/L2 signaling. For example, the notification of the pieces of information of items (1) to (4) to be described later and included in the downlink path loss measurement instruction can be done through RRC signaling, and the notification of information (5) can be done through MAC signaling. This provides for, for example, fast notification and signaling reduction for issuing an instruction to start measuring the downlink signal, on repeated SUL use start/stop conditions.

[0774] The following items (1) through (6) are disclosed as pieces of information included in the downlink pathloss measurement instruction:

[0775] (1) band for downlink signal;

[0776] (2) path loss offset;

[0777] (3) downlink signal sequence information;

[0778] (4) downlink signal transmission power;

[0779] (5) information indicating start or stop of downlink path loss measurement; And

[0780] (6) combinations of items (1) through (5) above.

[0781] The information in item (1) allows, for example, the UE to quickly measure the downlink signal.

[0782] Regarding item (1), the UE may, for example, set a downlink signal path loss offset to extract path loss in SUL. This allows, for example, the UE to more accurately extract the path loss in the SUL.

[0783] The information in item (3) may be, for example, SS sequence information. The information in item (3) may be cell ID information of the downlink signal. This allows, for example, the UE to quickly acquire a downlink signal.

[0784] The information in clause (4) allows the UE to calculate path loss using the received downlink signal power. Alternatively, for example, the gNB can reduce interference with other UEs by configuring a small downlink signal transmission power.

[0785] Regarding item (5), for example, the gNB may notify the UE of information indicating the start of downlink pathloss measurement when uplink communication using SUL is required. As an alternative example, the gNB may notify the UE of information indicating the stop of downlink pathloss measurement when the downlink pathloss measurement is unnecessary. This allows the UE to reduce the amount of processing and power consumption required to measure the loss in the downlink signal transmission path.

[0786] The information in clause (5) may be limited to information indicating the start of the downlink path loss measurement. After extracting the path loss in the SUL, the UE may stop measuring the path loss of the downlink signal. This may, for example, reduce the amount of signaling from the gNB to the UE.

[0787] gNB can dynamically switch between PSCell and PCell. For example, the gNB may pre-configure for the UE a cell to be a candidate for a PSCell or PCell. gNB can perform configuration through, for example, dedicated RRC signaling. gNB can change PSCell or PCell via MAC signaling. The gNB may notify the UE of the MAC signaling. The UE may change PSCell or PCell via MAC signaling. A PSCell or PCell change can be applied to communications using SUL. For example, a cell for an NR band and a cell for SUL may be candidates for a PSCell or a PCell. This makes it possible, for example, to quickly change the PSCell or PCell when the path loss varies as the UE moves, and reduce the amount of signaling due to the change in PSCell or PCell.

[0788] The gNB may configure a time advance group (TAG) in the SUL similar to cells in the NR band. For example, the gNB may configure the frame timing in the SUL in a manner similar to cells in the NR band. gNB and UE do not need to perform random access procedure using SUL. This allows, for example, the UE to quickly start using SUL.

[0789] FIG. 42 is a sequence diagram for the UE to determine the path loss in the SUL with the downlink measurement signal from the base station NR. Fig. 42 illustrates an example in which the UE configures a DC with a MeNB and an SgNB. Fig. 42 illustrates an example of using the same band in SUL as that in LTE. Fig. 42 illustrates an example in which the NR band is switched to SUL on uplink transmission at the UE. Fig. 42 illustrates an example of changing the PSCell according to the change from NR to SUL band. On FIG. 42, the solid lines represent communication over the interface between base stations, the dotted lines represent communication using the NR band, and the dashed lines represent communication using the band for LTE and SUL.

[0790] At Step ST6101 of FIG. 42, the UE transmits and receives uplink/downlink data to and from the SgNB. The NR band is used for transmission and reception. The NR band may be, for example, a frequency band as high as a few tens of GHz. In Step ST6102, the UE measures the path loss in the NR band with the downlink signal of Step ST6101.

[0791] At Step ST6103 of FIG. 42, the UE determines whether the path loss extracted in Step ST6102 is greater than or equal to a predetermined threshold. When the path loss is less than a predetermined threshold, the UE continues to transmit and receive uplink/downlink data in Step ST6101.

[0792] When the path loss is greater than and equal to the predetermined threshold in Step ST6103 of FIG. 42, the UE requests the SgNB to switch from the uplink NR band to SUL in Step ST6104. The UE may fulfill the request via, for example, RRC signaling. The UE may send a request in Step ST6104 in the NR band.

[0793] In Step ST6104 of FIG. 42 The UE may notify the SgNB request via the MeNB. Therefore, for example, the MeNB understands the UE's switch to SUL, which provides smooth control over the UE.

[0794] At Step ST6105 of FIG. 42 The SgNB sends a Secondary Base Station Modification Required notification (Required SN Modification) to the MeNB. The notification may include information about the PSCell change. The notification may include SUL configuration information. The information may be included in, for example, an SCG-Config signaling for notification.

[0795] At Step ST6101 of FIG. 42 The MeNB notifies the UE of the RRC connection reconfiguration signaling. The signaling may include PSCell change information. The signaling may include SUL configuration information. The UE switches from PSCell to SUL via signaling. In Step ST6107, the UE notifies the MeNB of the signaling to complete the RRC connection reconfiguration. In Step ST6108, the MeNB transmits a secondary base station modification confirmation notification (SN Modification Confirmation) to the SgNB.

[0796] At Step ST6109 of FIG. 42 The SgNB transmits a downlink measurement signal to the UE. SgNB can transmit a signal, for example, at a frequency as low as that in SUL. The UE receives the signal of Step ST6109 and extracts the path loss in the SUL in Step ST6110.

[0797] At Step ST6111 of FIG. 42, the UE may transmit the SgNB random access preamble. The UE may transmit the random access preamble with SUL. The UE may transmit the pathloss random access preamble in the SUL that was extracted in Step ST6110.

[0798] At Step ST6112 of FIG. 42 The SgNB may notify the UE of the random access response. The SgNB may notify the response with the NR band. In Step ST6113, the UE may send an SgNB random access procedure message 3. The UE may send message 3 using SUL. In Step ST6114, the SgNB may send a random access procedure message 4 to the UE. The SgNB may send message 4 using the NR band.

[0799] In Steps ST6115 and ST6116 of FIG. 42, the UE transmits and receives downlink/uplink data to and from the SgNB. In the downlink of Stage ST6115, the SgNB may use the NR band. In uplink communication, in Step ST6116, the UE may use SUL.

[0800] Although FIG. 42 illustrates a case where the UE measures the path loss in Step ST6102 and determines whether the path loss is greater than or equal to the threshold in Step ST6103, the gNB may measure the path loss and determine whether the path loss is greater than or are equal to the threshold value. Here, the gNB may measure the path loss using the uplink signal from the UE. This can, for example, avoid the complexity of the design at the UE and eliminate the need for signaling in Step ST6104, which can reduce the amount of signaling over the Uu interface.

[0801] The sixth embodiment allows the UE to more accurately measure the path loss in the SUL. Therefore, SUL transmission from the UE can be performed with an appropriate power, and interference from the UE to other base stations can be reduced.

[0802] Seventh Embodiment

Reference signals (RS) in DL include DMRS, Phase Tracking RS (PTRS), Tracking RS (TRS), and CSI-RS. DMRS includes front loading DMRS (FL-DMRS) and optional DMRS (add-DMRS). FL-DMRS is mapped to start symbols on the PDSCH. Upon receiving FL-DMRS at the beginning, the UE may demodulate the data mapped in subsequent symbols earlier.

[0803] Since FL-DMRS is necessary for demodulation, it is preferable not to preempt FL-DMRS. However, in the absence of preemption of symbols in which FL-DMRS is displayed for this purpose, data for the URLLC UE cannot be transmitted with the timing of the symbols in which FL-DMRS is displayed. For example, when there is data for the URLLC UE with timing, the resources for the URLLC UE cannot be reserved, and thus the data for the URLLC UE must be deferred.

[0804] For example, since the FL-DMRS consists of one or two symbols in NR, the transmission is delayed by the number of symbols. This may increase the amount of timeout in the URLLC connection of the UE.

[0805] The seventh embodiment discloses a method for solving such a problem.

[0806] Only resources in which FL-DMRS is not displayed in symbols in which FL-DMRS is displayed can be configured as resources for preemption. DMRS is configured per UE per RE. Resources to preempt must be REs in which FL-DMRS is not mapped. The PDSCH is transmitted in REs except for REs in which FL-DMRS is mapped in symbols in which FL-DMRS is mapped. The PDSCH transmission area must be configurable as resources to preempt.

[0807] A Purge Indication (PI) is transmitted for the eMBB UE. The gNB includes in the PI information about the resources to be preempted for the eMBB UE in order to notify the eMBB UE of the PI. The resources to be evicted can be information specified per RE. Resources to be preempted may be configured in accordance with the above method, being specified per RE. Upon receiving the PI, the eMBB UE recognizes the lack of transmission with resources to be preempted. The eMBB UE may receive resources for other PDSCHs except for resources that must be preempted.

[0808] This can reserve resources for the URLLC UE also in symbols in which FL-DMRS is displayed. Thus, it is not necessary to delay data transmission for the URLLC UE by a number of symbols in which FL-DMRS is displayed. This can reduce the increase in the latency value in the URLLC connection of the UE.

[0809] Such a method should be applied to other RSs. Only resources that do not display RS in symbols that display RS can be configured as resources to preempt. This can create exactly the same benefits.

[0810] However, the amount of resources for the URLLC UE that can be reserved in symbols in which FL-DMRS is displayed is reduced in accordance with the above method. For example, since the number of REs that can be reserved in symbols and that can be reserved with the timing of one slot for URLLC is less than normal, the amount of data that can be transmitted in one slot is reduced. For example, when a high capacity link occurs, the ultra-reliable, low latency characteristics of the URLLC link are not provided.

[0811] Disclosed is a method for solving such a problem.

[0812] FL-DMRS is preemptive. FL-DMRS preemption is configurable.

[0813] FIG. 43 illustrates an example of FL-DMRS preemption for an eMBB UE. Resources displaying the FL-DMRS configured in the slot for the eMBB UE are pushed out as resources for the URLLC UE. The gNB does not handover for the eMBB UE using preempted resources. Here, the gNB does not transmit FL-DMRS for the eMBB UE. The gNB passes a slot (possibly a mini-slot) to the URLLC UE using preempted resources. The gNB shall transmit channels and/or DL signals for the URLLC UE in the slot.

[0814] DMRS is configured per UE per RE. Resources to preempt must be REs that display FL-DMRS. The PDSCH is transmitted in REs except for REs in which FL-DMRS is displayed, in symbols in which FL-DMRS is displayed. A larger PDSCH transmission area may be allocated to the eMBB UE.

[0815] Resources for preemption need not be limited to REs in which FL-DMRS is displayed. Symbols in which FL-DMRS is displayed may include REs in which FL-DMRS is displayed and REs in which other signals or channels are displayed. This may increase the resources for preemption.

[0816] The resources to be preempted along the frequency axis may be specified per resource element group (REG). REG is an RE group with the same bandwidth as the PRB. Resources for preemption can be configured per REG in symbols in which FL-DMRS is displayed. The resources for the URLLC UE may be configured per REG or per PRB.

[0817] A Purge Indication (PI) is transmitted for the eMBB UE. The gNB includes in the PI information about the resources to be preempted for the eMBB UE in order to notify the eMBB UE of the PI. Upon receiving the PI, the eMBB UE recognizes the lack of transmission with resources to be preempted. The eMBB UE may receive resources for other PDSCHs except for resources that must be preempted.

[0818] DMRS is mapped to a different RE for each UE. The same RE may be configured for DMRS of multiple UEs. The DMRS for each of the UEs for which the same RE has been configured is multiplexed with, for example, an orthogonal code. Resource information notification for preemption may be performed for each UE or a group of UEs consisting of one or more UEs. The UE group may be a group of UEs whose DMRSs are configured in the same RE.

[0819] The PI may be transmitted for each eMBB UE or for each group of UEs. The transmission for each UE group may reduce the amount of signaling.

[0820] FIG. 44 illustrates an example of FL-DMRS preemption applied to an eMBB UE. A part of the symbols in which the PDSCH and FL-DMRS are mapped, which are configured in the slot for the eMBB UE, is pushed out as resources for the URLLC UE. The gNB does not handover for the eMBB UE using preempted resources. The gNB may only prevent transmission with resources for FL-DMRS and PDSCH that are preempted.

[0821] The gNB passes the slot to the URLLC UE using preempted resources. The gNB shall transmit channels and/or DL signals for the URLLC UE in the slot. This may support slot configuration for an arbitrary URLLC UE.

[0822] The PI is transmitted for the eMBB UE. Since this is identical to that shown in Fig. 43, the description of this is omitted.

[0823] The gNB does not handover for the eMBB UE using preempted resources. As an alternative over FL-DMRS, the gNB may not allow all of the FL-DMRS to be mapped to symbols that are preempted for FL-DMRS. Here, resource information for preemption to be notified to the eMBB UE by the PI should be resources for the entire FL-DMRS.

[0824] However, when FL-DMRS is preemptive, FL-DMRS is not transmitted. Thus, FL-DMRS cannot be used for data demodulation for an eMBB UE. Thus, the eMBB UE cannot demodulate the data. The seventh embodiment discloses a method for solving such a problem.

[0825] When FL-DMRS and add-DMRS are configured for the eMBB UE, FL-DMRS is preemptively performed. FL-DMRS can be configured as resources to preempt. When FL-DMRS and add-DMRS are configured for the eMBB UE, one of the FL-DMRS and add-DMRS must be configured not to be preempted for resources in relation to the URLLC of the UE.

[0826] The characters in which add-DMRS can be displayed are predefined in the standard. The gNB notifies the UE of the add-DMRS configuration in advance. In the case where add-DMRS is configured, even when FL-DMRS is preempted and thus not transmitted, using add-DMRS can improve performance for demodulating data to be mapped on the PDSCH.

[0827] The gNB notifies the eMBB UE of the resources to preempt with the PI. The gNB notifies the UE of the resources for the PI in advance. Upon receiving the resources, the UE may receive the PI. The resources for the PI may be in a slot that is identical to or different from the one used for the resources to preempt.

[0828] When FL-DMRS and add-DMRS are configured for the eMBB UE, characters other than characters in which FL-DMRS is displayed, characters other than characters in which add-DMRS is displayed, or characters other than characters in which FL is displayed -DMRS and the characters that add-DMRS maps to can be configured as resources to preempt.

[0829] Resources for preemption may be configured per symbol, in symbols in which DMRS are displayed. For example, when the DMRS is composed of a plurality of symbols, configuring resources to preempt per symbol, only one of the symbols in the DMRS is made configurable as resources to preempt. For example, when one DMRS symbol is configured for each UE, then the DMRS may be configured as resources for preemption.

[0830] The resources to be preempted may be configured not per character, but per resource element group (REG) or per resource element (RE), each of which displays a DMRS. The resources to preempt must be configured per REG or per RE, instead of per character.

[0831] For example, when DMRS are discretely displayed in the frequency axis direction, configuring resources to preempt per REG or per RE makes only the REG or RE in which the DMRS is displayed configurable as resources to preempt. For example, when the DMRS of multiple UEs are configured in one symbol by FDM, the UE to be preempted may be configured, and the DMRS of the UE may be configured as resources to preempt.

[0832] The information included in the PI may be, for example, resource information to preempt. Examples of the information include resource information on the frequency axis and resource information on the time axis. The resource information may be, for example, information per character, per REG, or per RE. This allows the eMBB UE to identify resources to preempt. The resource information may be, for example, a slot number. This is effective when the resources to preempt are in a slot other than the one in which the PI is being passed.

[0833] Information indicating relative values with respect to the slot in which the PI was notified may be used instead of the slot number. Relative values can be numbered with integers greater than or equal to zero. This is effective when the resources to preempt are in the slot before the PI.

[0834] FIG. 45 illustrates an example of FL-DMRS preemption when FL-DMRS and add-DMRS are configured for the eMBB UE. FL-DMRS and add-DMRS are configured in the same slot for the eMBB UE. Symbols to which FL-DMRS is mapped to the eMBB UE are pushed out as resources to the URLLC UE. The gNB does not handover for the eMBB UE using preempted resources. Here, the gNB does not transmit FL-DMRS for the eMBB UE. The gNB passes the URLLC slot to the UE using preempted resources. The gNB shall transmit channels and/or DL signals for the URLLC UE in the slot.

[0835] The PI is transmitted for the eMBB UE. The gNB includes in the PI information about the resources to be preempted for the eMBB UE in order to notify the eMBB UE of the PI. Upon receiving the PI, the eMBB UE recognizes the lack of transmission with resources to be preempted. The eMBB UE may receive resources for other PDSCHs except for resources that must be preempted. The eMBB UE receives the add-DMRS configured in the same slot. The eMBB UE may demodulate the PDSCH with add-DMRS.

[0836] The gNB may configure add-DMRS in advance such that FL-DMRS is made preemptive. For this, a method for configuring add-DMRS can be applied. Even when FL-DMRS is preempted and thus not transmitted, add-DMRS can be used and performance can be improved to demodulate data to be mapped on the PDSCH.

[0837] When only FL-DMRS is configured for the eMBB UE (when add-DMRS is not configured), FL-DMRS should be non-preemptive. FL-DMRS shall be non-configurable as resources to preempt. When only FL-DMRS is configured for the eMBB UE (when add-DMRS is not configured), FL-DMRS must be configured not to be preempted for resources for the URLLC UE.

[0838] Resources for preemption may not be configurable per symbol in symbols in which DMRS is displayed. For example, when the DMRS is composed of a plurality of symbols, performing resources to preempt non-configurable per symbol may make only one symbol in the DMRS non-configurable as resources to preempt. For example, when a DMRS consisting of two symbols is configured per UE, one of the symbols in the DMRS may be made non-configurable as resources for preemption.

[0839] The resources to preempt may not be configurable per REG or per RE. For example, when multiple DMRSs are discretely configured in one symbol, one of the DMRSs may be non-configurable as resources to preempt.

[0840] Therefore, for example, the UE may perform demodulation with non-configurable DMRS as resources for preemption.

[0841] When FL-DMRS is configured and add-DMRS is not configured for the eMBB UE, FL-DMRS may be preemptive. FL-DMRS can be configured as resources to preempt.

[0842] Simply enabling FL-DMRS preemption may deprive the eMBB UE of the ability to demodulate PDSCH data. Some original invention is needed. The solution is revealed here.

[0843] Additional DMRS is configured for the eMBB UE. The add-on DMRS is configured in the DL region in the same slot as that of the preempted FL-DMRS and is used to demodulate the PDSCH data. When FL-DMRS is preempted, FL-DMRS cannot be used, but supplemental DMRS is used for demodulation.

[0844] The gNB does not transmit data to the eMBB UE using the resources with which the incremental DMRS has been configured. The gNB transmits the incremental DMRS using the resources with which the incremental DMRS was configured. This may avoid contention between configured incremental DMRS transmission and data transmission. The gNB notifies the eMBB UE of the incremental DMRS information. Examples of information about the incremental DMRS include the configuration of the incremental DMRS and the resources with which the incremental DMRS is configured.

[0845] The incremental DMRS is generated using the incremental DMRS information, and the generated incremental DMRS is mapped to the DL resources. Other information may be used together in generating and displaying the incremental DMRS. Examples of other information include a UE ID.

[0846] The gNB configures FL-DMRS as preemption resources for the UE to configure incremental DMRS. The gNB notifies the UE of the resources to preempt using the PI. A PI may be provided to notify additional DMRS information. The gNB shall notify the UE of the incremental DMRS information via the PI. PI Notification provides dynamic configuration of the incremental DMRS.

[0847] The gNB may include information about the incremental DMRS in the PI to be used for resource notification for preemption to notify information. The management resources that the gNB needs to notify the UE are reduced by including information in the same PI and notifying it.

[0848] As previously described, the DMRS of multiple UEs may be multiplexed with the same resources along the frequency-time axes. The DMRS of multiple UEs may be multiplexed with the same symbol. Thus, when FL-DMRS and add-DMRS are preempted, preemption resources can be configured and notification of preemption resource information can be performed per UE or per UE group.

[0849] Additional DMRS may be multiplexed in a manner similar to that used for FL-DMRS or add-DMRS. The incremental DMRS may be configured per UE or per group of UEs. For example, when incremental DMRS is configured for multiple UEs with the same resources, configuring resources for incremental DMRS for each UE group may reduce the amount of configuration information.

[0850] A gNB may notify incremental DMRS information to each UE or each group of UEs. A UE group may consist of one or more UEs for which incremental DMRS is configured. This is effective, for example, when resources for incremental DMRS are configured per UE group. The amount of signaling for configuration notification can be reduced.

[0851] FIG. 46 illustrates an example of FL-DMRS preemption when only FL-DMRS is configured in one slot for the eMBB UE. FL-DMRS is configured in one slot for the eMBB UE. Symbols in which FL-DMRS is mapped to the eMBB UE are pushed out as resources to the URLLC UE. The gNB does not handover for the eMBB UE using preempted resources. Here, the gNB does not transmit FL-DMRS for the eMBB UE. The gNB passes the slot to the URLLC UE using preempted resources. The gNB shall transmit channels and/or DL signals for the URLLC UE in the slot.

[0852] gNB configures additional DMRS in the same slot. Data is not displayed using the resources with which the incremental DMRS was configured. The gNB transmits incremental DMRS and does not transmit data using the resources with which incremental DMRS was configured.

[0853] The PI is transmitted for the eMBB UE. In the example in FIG. 46 gNB includes in one PI resource information to be preempted for the eMBB UE and additional DMRS information to notify the eMBB UE of the PI. Upon receiving the PI, the eMBB UE recognizes the lack of transmission with the resources to be preempted and recognizes the resources with which the incremental DMRS is configured.

[0854] The eMBB UE may receive resources for other PDSCHs except for resources to be preempted and resources with which supplemental DMRS is configured. The eMBB UE receives an additional DMRS configured in the same slot. The eMBB UE may demodulate the PDSCH with additional DMRS.

[0855] The supplemental DMRS is transmitted from a transmission point identical to that of the original FL-DMRS and/or data (PDSCH).

[0856] As an alternative method, the incremental DMRS may have a quasi-co-location relationship with the original FL-DMRS. And/or the supplemental DMRS may have a quasi-collocation with data (PDSCH) relationship. Therefore, even when the added DMRS is transmitted from a transmission point other than that of the original FL-DMRS or data, the demodulation result of the added DMRS can be considered as the demodulation result of the original FL-DMRS, and the added DMRS can be used as data for demodulation. .

[0857] The gNB may notify the UE of the quasi-collocation relationship information. Flexible configuration possible. gNB can advertise information via RRC signaling. This provides a semi-static configuration and may reduce the amount of signaling to be notified. Alternatively, the gNB may include information in the PI to notify the information. This provides dynamic configuration.

[0858] The incremental DMRS may be mapped to resources following the resources to be evicted. Alternatively, the incremental DMRS may be mapped to the symbols following the symbols to be preempted in the symbols to which the PDSCH is mapped in the same slot. This can shorten the duration from the appearance of data for the URLLC UE to the transmission of data more than when the additional DMRS is mapped to the symbols following the symbols to be preempted.

[0859] Six examples of additional DMRS configuration information are disclosed below:

[0860] (1) number of symbols of the extension DMRS;

[0861] (2) type of incremental DMRS, or possibly an orthogonal method for incremental DMRS;

[0862] (3) extension DMRS port number;

[0863] (4) Extension DMRS Encryption ID;

[0864] (5) incremental DMRS sequence information, eg ZC root score such as CS; And

[0865] (6) combinations of items (1) through (5) above.

[0866] The resource information by which the incremental DMRS is configured includes time resource information and frequency resource information. Seven examples of resource information with which incremental DMRS is configured are described below:

[0867] (1) character number;

[0868] (2) slot number, or possibly mini-slot number;

[0869] (3) subcarrier number, or possibly subcarrier number in the PRB;

[0870] (4) RE number or possibly RE number in PRB;

[0871] (5) REG number;

[0872] (6) PRB number; And

[0873] (7) combinations of items (1) through (6) above.

[0874] Although the notification of the appendix DMRS configuration by the PI is disclosed, the notification of the appendix DMRS configuration can be done via RRC signaling. Notification can be made through UE-dedicated RRC signaling. This can reduce the amount of information in the PI. Receive errors by the UE can be reduced.

[0875] Although the notification of the resources by which the incremental DMRS is configured is disclosed by the PI, the notification of the resources by which the incremental DMRS is configured can be done via RRC signaling. Notification can be made through UE-dedicated RRC signaling. This can reduce the amount of information in the PI. Receive errors by the UE can be reduced.

[0876] The operation of gNB is disclosed. The gNB does not transmit FL-DMRS to the eMBB UE using the configured resources to preempt. When resources not only for the FL-DMRS but also for the PDSCH are designated as resources for preemption, the gNB does not transmit data to be mapped on the PDSCH. The gNB does not transmit data for the eMBB UE using the configured resources for the incremental DMRS.

[0877] The gNB may transmit in symbols for the PDSCH in the same slot the data for the eMBB UE to be transmitted with resources for preemption or resources for supplemental DMRS. The symbols for the PDSCH in the same slot may be the symbols following the resources to preempt or the symbols following the symbols for the extension DMRS. The data for each eMBB UE to be transmitted and the symbols in which the data is transmitted may be configurable.

[0878] This can reduce downlink data loss and the number of retransmissions.

[0879] The gNB may change the coding rate of the data for the eMBB UE to be transmitted with the resources for preemption or the resources for the incremental DMRS, and transmit the data. The gNB can change the symbol data rate for the PDSCH in the same slot and transmit data. The gNB may change the coding rate of the data for the eMBB UE to be transmitted with the resources for preemption or the resources for the incremental DMRS, and the coding rate of the data to be transmitted in the symbols in which the data for the eMBB UE is transmitted, and transmit data fragments.

[0880] With this method, the gNB can transmit data to be transmitted in the same slot. gNB can transmit downlink data with low latency.

[0881] The gNB may transmit, in symbols following the symbols to preempt, data for the eMBB UE to be transmitted with resources for the incremental DMRS. The gNB may transmit, in symbols following the symbols to be preempted in the same slot, data for the eMBB UE to be transmitted with resources for the incremental DMRS.

[0882] The gNB may change the coding rate of the data for the eMBB UE to be transmitted with the resources for incremental DMRS, and transmit the data in symbols following the symbols to be preempted in the same slot. The gNB may change the coding rate of the data following the padding symbols in the same slot and transmit data to the eMBB UE in the symbols following the padding symbols in the same slot. The gNB may change the coding rate of the data for the eMBB UE to be transmitted with the resources for the incremental DMRS and the coding rate of the data following the symbols for preemption in the same slot, and transmit the data for the eMBB UE in symbols following the symbols for evictions in the same slot.

[0883] This can reduce the coding rate of the data for the eMBB UE to be transmitted with the resources for incremental DMRS and improve the demodulation efficiency in the gNB.

[0884] The gNB notifies the UE of the coding rate information. The gNB may include information in the PI for notifying resources to preempt to notify information. And/or the gNB may include coding rate information in the PI to notify supplemental DMRS information to notify the information. Examples of coding rate information include coding rate and data coverage within which the coding rate is applied.

[0885] Examples of data coverage within which the reported coding rate is applied include data for the eMBB UE to be transmitted with resources for the incremental DMRS, data following the symbols of the incremental DMRS, and data following characters to override. The data coverage may be split and the encoding rate may be configured for each of the split data coverages. The gNB may associate each of the data coverages with a code rate to notify them.

[0886] Therefore, the UE can easily demodulate the data for the eMBB UE to be transmitted with the resources for the incremental DMRS and the data following the symbols for preemption.

[0887] The gNB uses the configured resources to preempt for DL communication with the URLLC UE. gNB maps channels and/or DL signals to URLLC UEs in resources to preempt. Examples of DL channels include a data channel and a control channel. The PDCCH may be mapped as a control channel. The DCI may be mapped to the PDCCH and transmitted. URLLC UE receives DL channels and/or signals.

[0888] Upon receiving the PI of the preemption resources from the gNB, the eMBB UE recognizes the transmission of the DL with the preemption resources that are included in the PI. The eMBB UE also recognizes the absence of FL-DMRS transmission. Upon receiving the PI including the incremental DMRS information from the gNB, the eMBB UE recognizes that the incremental DMRS is to be transmitted with resources for the incremental DMRS. The eMBB UE may receive the supplemental DMRS and perform demodulation with the supplemental DMRS.

[0889] FIG. 47 and 48 illustrate an example of a process flow for preempting FL-DMRS when only FL-DMRS is configured in a slot for an eMBB UE. Fig. 47 and 48 are connected via boundary location BL4748. Fig. 47 and 48 illustrate the case where the incremental DMRS is configured.

[0890] In Step ST2001, the gNB configures FL-DMRS for the eMBB UE. gNB does not configure add-DMRS. In Step ST2002, the gNB configures, for example, resources and PI transmission timing for the eMBB UE. The gNB also configures, for example, the resources and transmission timing of the PI for the incremental DMRS for the eMBB UE. Examples of transmission timing include period, offset information, slot number, and symbol number. This may be configured per UE or per group of UEs.

[0891] The gNB may notify the eMBB UE of information indicating that preemptive processes should be performed. gNB may notify the information in Step ST2003. Therefore, the eMBB UE can recognize that preemptive processes are to be performed. Upon receipt of the eMBB information, the UE shall use the PI configuration for preemption and the configuration for incremental DMRS that it was notified in Step ST2003.

[0892] The gNB does not need to notify the eMBB UE of information indicating that preemptive processes should be performed. Notification of a PI configuration for preemption or a configuration for incremental DMRS from a gNB may trigger preemptive processes. The eMBB UE determines that preemptive processes are initiated by notifying the PI configuration for preemption or the configuration for incremental DMRS in Step ST2003.

[0893] In Step ST2003, the gNB notifies the eMBB UE of the FL-DMRS configuration information, the add-DMRS configuration information, the PI configuration information for preemption, and the PI configuration information for additional DMRS. The gNB may implement this notification via RRC signaling or using a UE-dedicated notification.

[0894] In Step ST2004, the gNB performs scheduling for the eMBB UE. In Step ST2005, the gNB transmits the PDCCH, PDSCH, and RS to the eMBB UE according to the scheduling result. The eMBB UE receives the various configurations notified in Step ST2003 and the PDCCH, PDSCH and RS notified in Step ST2005 to receive the data mapped to the PDSCH.

[0895] In Step ST2006, the eMBB UE for which preemptive processes have been configured stores the PDSCH reception result for a predetermined duration. Upon receiving the supplemental DMRS configured in the same slot, the eMBB UE may demodulate the PDSCH in the same slot.

[0896] Upon arrival of the URLLC UE data in Step ST2007, the gNB determines the FL-DMRS of the eMBB UE as resources to preempt for the URLLC UE in Step ST2008. The gNB that has determined the FL-DMRS as resources to preempt configures the incremental DMRS in Step ST2009.

[0897] In Step ST2010, the gNB notifies the eMBB UE of the PI to preempt. In Step ST2011, the gNB does not transmit to the eMBB UE with resources to preempt. The gNB transmits the PDSCH to the eMBB UE using resources other than the resources to preempt. In Step ST2012, the gNB passes the slot for the URLLC UE to the URLLC UE with resources to preempt. The gNB sends the PDCCH, PDSCH and RS to the URLLC UE in the slot.

[0898] In Step ST2013, the gNB transmits the PI for incremental DMRS to the eMBB UE. In Step ST2014, the gNB transmits the incremental DMRS to the eMBB UE with resources for the incremental DMRS. In Step ST2015, the eMBB UE demodulates the PDSCH with the supplemental DMRS received with the incremental DMRS information that it has been notified from the gNB to receive data.

[0899] This can make FL-DMRS for the eMBB UE preemptive. The eMBB UE may demodulate with the incremental DMRS the data mapped on the PDSCH, while the URLLC UE may receive the data transmitted to the URLLC UE with the resources to preempt. This provides high speed and high capacity communication for the eMBB UE and low latency communication for the URLLC UE.

[0900] Another method for notification of incremental DMRS is disclosed. The gNB notifies the UE of the incremental DMRS information via RRC signaling. The gNB notifies, via the PI, the UE of the configuration/non-configuration information of the incremental DMRS. Activation/deactivation can be used as configuration/non-configuration information of the extension DMRS. Activation notification occurs when the incremental DMRS is configured, and deactivation notification occurs when the incremental DMRS is not configured.

[0901] Therefore, the eMBB UE can recognize whether the supplemental DMRS is being configured with the configuration and resources for the supplemental DMRS that it has been notified through RRC signaling. Although an example of notification of configuration/non-configuration information by PI is disclosed, only information indicating configuration by PI may be notified, or only information indicating non-configuration by PI may be notified. When only information indicating configuration is notified, the absence of such information shall indicate non-configuration. When only information indicating a non-configuration is notified, the absence of such information shall indicate a configuration.

[0902] This may reduce the amount of information notified by the PI.

[0903] Disclosed is another method for notification of incremental DMRS. The gNB notifies the UE of candidate information for incremental DMRS via RRC signaling. The number of candidates may be one or more. Candidates may be numbered. The gNB notifies, via the PI, the UE which incremental DMRS candidate is to be configured. Therefore, the eMBB UE can select the supplemental DMRS information that it has been notified by the PI from the supplemental DMRS candidate information that it has been notified via RRC signaling and recognize the supplemental DMRS configuration.

[0904] This can reduce the amount of information notified by the PI.

[0905] Part or all of the add-DMRS configuration may be identical to that of the add-DMRS. And/or the frequency resources by which the add-DMRS is configured may be identical to those of the add-DMRS. This may result in performance equivalent to that of add-DMRS. In addition, there is no need to separately configure the incremental DMRS, which can contribute to processes and schema configurations in the eNB and UE.

[0906] When an add-DMRS is configured in exactly the same way as an add-DMRS, such a configuration may be statically defined in the standard. Alternatively, information indicating that the add-DMRS is configured in exactly the same way as the add-DMRS may be provided and notified by the PI. Alternatively, notification of the information may be via RRC signaling.

[0907] The set of add-DMRS configurations may be numbered. The gNB notifies, via the PI, the UE which add-DMRS configuration is in use. Therefore, the eMBB UE can, for example, select the add-DMRS configuration information that it has been notified by the PI from the add-DMRS candidate configuration information that it has been notified via RRC signaling, and recognize the configuration as an extension DMRS configuration.

[0908] Other supplemental DMRS information may include power information. The power information may be power information configured for the supplemental DMRS. Alternatively, the power information may be power difference information configured for FL-DMRS or power difference information configured for PDSCH.

[0909] Configuring the supplemental DMRS power information provides a configuration more appropriate for, for example, resources for configuring the incremental DMRS, a state such as the rate of the eMBB UE, or channel quality, which can improve demodulation performance. Since excessively high power can be prevented from being configured, the power consumption in the gNB can be reduced.

[0910] As previously described, the gNB may notify the eMBB UE of power information via PI or via RRC signaling. Alternatively, the power information may be statically predefined in the standard.

[0911] The power configured for incremental DMRS may be identical to that for FL-DMRS. The power configured for incremental DMRS may be statically predefined in the standard. Additional DMRS information can be reduced.

[0912] FIG. 49 illustrates an example of FL-DMRS preemption when only FL-DMRS is configured in one slot for the eMBB UE. FL-DMRS is configured in one slot for the eMBB UE. Part of the symbols in which the FL-DMRS and PDSCH are mapped, which are configured in the slot for the eMBB UE, are popped out as resources for the URLLC UE. The gNB does not handover for the eMBB UE using preempted resources. The gNB passes the slot to the URLLC UE using preempted resources. The gNB shall transmit channels and/or DL signals for the URLLC UE in the slot.

[0913] gNB configures additional DMRS in the same slot. The gNB can only configure the preempted FL-DMRS as an additional DMRS. The additional DMRS may be configurable per RE or per REG in the direction of the frequency axis. Alternatively, the incremental DMRS may be configurable per resource for FL-DMRS per UE. The PDSCH is not mapped by the resources with which the incremental DMRS was configured. The gNB transmits the incremental DMRS and does not transmit the PDSCH using the resources with which the incremental DMRS was configured.

[0914] The resources for additional DMRS on the frequency axis may be different from those for FL-DMRS on the frequency axis. For example, the resources for incremental DMRS on the frequency axis may be resources for all frequency bands to which the PDSCH is mapped. This can improve demodulation efficiency for channel variations along the frequency axis.

[0915] Since the PI transmission method is identical to that in FIG. 46, its description is omitted. The eMBB UE may receive resources for other PDSCHs except for the resources to be preempted and the resources with which the incremental DMRS is configured. The eMBB UE receives an additional DMRS configured in the same slot. The eMBB UE may demodulate the PDSCH with additional DMRS.

[0916] FIG. 50 illustrates an example of FL-DMRS preemption when only FL-DMRS is configured in one slot for the eMBB UE. FL-DMRS is configured in one slot for the eMBB UE. Part of the symbols in which FL-DMRS and PDSCH are mapped, which are configured in the slot for the eMBB UE, are popped out as resources for the URLLC UE. The gNB does not handover for the eMBB UE using preempted resources. The gNB passes the slot to the URLLC UE using preempted resources. The gNB shall transmit DL channels and/or signals for the URLLC UE in the slot.

[0917] gNB configures additional DMRS in the same slot. The gNB can only configure the preempted FL-DMRS as an additional DMRS. The additional DMRS may be configurable per symbol in the direction of the time axis. Alternatively, the incremental DMRS may be configurable per resource for FL-DMRS per UE. The PDSCH is not mapped by the resources with which the incremental DMRS was configured. The gNB transmits the incremental DMRS and does not transmit the PDSCH using the resources with which the incremental DMRS was configured.

[0918] The resources for the incremental DMRS along the time axis may differ from those for the FL-DMRS along the time axis. For example, the resources for incremental DMRS along the time axis may be n symbols (n≥1). For example, by making n larger than that of the original FL-DMRS, one can improve the demodulation efficiency for channel variations along the time axis.

[0919] Since the method for transmitting PI is the same as that in FIG. 46, its description is omitted. The eMBB UE may receive resources for other PDSCHs except for the resources to be preempted and the resources with which the incremental DMRS is configured. The eMBB UE receives an additional DMRS configured in the same slot. The eMBB UE may demodulate the PDSCH with additional DMRS.

[0920] Disclosed is performing FL-DMRS with preemptive capability and configuring add-DMRS when only FL-DMRS is configured for an eMBB UE (when add-DMRS is not configured).

[0921] Part or all of the additional DMRS configuration may be identical to that of the FL-DMRS. And/or the frequency resources by which the incremental DMRS is configured may be identical to those of the FL-DMRS. This can result in performance equivalent to that of the FL-DMRS. Moreover, it can facilitate processes and schema configurations in gNBs and UEs.

[0922] When the incremental DMRS is configured in exactly the same way as the FL-DMRS, such a configuration may be statically defined in the standard. Alternatively, information indicating that the incremental DMRS is configured in exactly the same manner as the FL-DMRS may be provided and notified by the PI. Alternatively, the information may be notified via RRC signaling. This may reduce the amount of information needed by the gNB to configure the incremental DMRS for the UE.

[0923] The displaced FL-DMRS may be shifted. The preempted FL-DMRS is configured in a different DL area in the same slot. The preempted FL-DMRS may be configured in symbols following the symbols to be preempted in the same slot. Therefore, when FL-DMRS is preempted, FL-DMRS which is time shifted is used for demodulation.

[0924] The method for configuring data for the incremental DMRS and PDSCH can be applied to the method for configuring data for the shifted FL-DMRS and PDSCH. The gNB may notify the eMBB UE of the FL-DMRS offset information. For example, the incremental DMRS information may be an offset amount. For example, the number of symbols information is the number of symbols to be shifted. For example, the information about the number of REs is the number of REs to be shifted.

[0925] It has been disclosed that the incremental DMRS is generated using the incremental DMRS information and mapped to the DL resources. The FL-DMRS may differ in the sequence to be generated, for example, depending on, for example, the number of symbols from the symbols to which the FL-DMRS is mapped. Similarly, when an extension DMRS is generated, a sequence should be used, which should be generated according to, for example, the number of symbols from the symbols into which the extension DMRS is mapped.

[0926] As an alternative method, when the incremental DMRS is configured in exactly the same manner as the FL-DMRS, or when the FL-DMRS is shifted, the same DMRS as the original FL-DMRS may be used. Only resources that need to be rendered can be made distinct. This enables demodulation with the original FL-DMRS configuration, whichever symbol the resources are mapped to. This facilitates the demodulation process and reduces the processing time.

[0927] FIG. 51 illustrates an example of FL-DMRS preemption when only FL-DMRS is configured in one slot for the eMBB UE. Fig. 51 illustrates an example in which the incremental DMRS has the same configuration as that of the FL-DMRS and is obtained by time-shifting the FL-DMRS.

[0928] FL-DMRS is configured in one slot for the eMBB UE. Symbols to which FL-DMRS is mapped to the eMBB UE are pushed out as resources to the URLLC UE. The gNB does not handover for the eMBB UE using preempted resources. Here, the gNB does not transmit FL-DMRS for the eMBB UE. The gNB passes the slot to the URLLC UE using preempted resources. The gNB shall transmit channels and/or DL signals for the URLLC UE in the slot.

[0929] gNB configures additional DMRS in the same slot. The add-on DMRS has the same configuration as that of the FL-DMRS and is obtained by time-shifting the FL-DMRS. The PDSCH is not mapped by the resources with which the incremental DMRS was configured. The gNB transmits the incremental DMRS and does not transmit the PDSCH using the resources with which the incremental DMRS was configured.

[0930] The PI is transmitted for the eMBB UE. The gNB includes in the PI information about resources to be preempted for the eMBB UE and additional DMRS information to notify the eMBB UE of the PI. Examples of the extension DMRS information include information indicating that the extension DMRS has exactly the same configuration as that of FL-DMRS and the number of symbols to be shifted.

[0931] Upon receiving the PI, the eMBB UE recognizes the lack of transmission with the resources to be preempted, and recognizes the resources with which the incremental DMRS is configured.

[0932] The eMBB UE may receive resources for other PDSCHs except for the resources to be preempted and the resources with which the incremental DMRS is configured. The eMBB UE receives an additional DMRS configured in the same slot. The eMBB UE may demodulate the PDSCH with additional DMRS.

[0933] FIG. 52 illustrates an example of FL-DMRS preemption when only FL-DMRS is configured in one slot for the eMBB UE. Fig. 52 illustrates an example in which the incremental DMRS has exactly the same configuration as that of the FL-DMRS and is obtained by time-shifting the FL-DMRS.

[0934] FL-DMRS is configured in one slot for the eMBB UE. Part of the symbols to which FL-DMRS and PDSCH are mapped, which are configured in the slot for the eMBB UE, are popped out as resources for the URLLC UE. The gNB does not handover for the eMBB UE using preempted resources. Here, the gNB does not perform FL-DMRS for the eMBB UE. The gNB passes the slot to the URLLC UE using preempted resources. The gNB shall transmit channels and/or DL signals for the URLLC UE in the slot.

[0935] gNB configures additional DMRS in the same slot. The add-on DMRS has exactly the same configuration as that of the FL-DMRS and is obtained by time-shifting the FL-DMRS. On FIG. The 52 incremental DMRS is configured to be time-shifted by the resources being preempted. The PDSCH is not mapped by the resources with which the incremental DMRS was configured. The gNB transmits the incremental DMRS and does not transmit the PDSCH using the resources with which the incremental DMRS was configured. Since the method for transmitting PI is identical to that in FIG. 51, its description is omitted.

[0936] The eMBB UE may receive resources for other PDSCHs except for the resources to be preempted and the resources with which the incremental DMRS is configured. The eMBB UE receives an additional DMRS configured in the same slot. The eMBB UE may demodulate the PDSCH with additional DMRS.

[0937] Although add-DMRS configuration is disclosed as a method to make FL-DMRS preemptive, when FL-DMRS is configured and add-DMRS is not configured for the eMBB UE, it is not limited to this. The add-DMRS may be configured when add-DMRS is configured. gNB can configure additional DMRS in an arbitrary slot. The gNB may configure additional DMRS, for example, when the eMBB UE moves at high speeds. The gNB may configure additional DMRS in addition to FL-DMRS or add-DMRS. Configuring additional DMRS can improve demodulation efficiency.

[0938] The CSI-RS may be configurable as resources to preempt. A method for configuring an incremental DMRS may be applied to a method for preempting CSI-RS. The incremental CSI-RS is configured when the CSI-RS is configured as resources to preempt. Configuring the incremental CSI-RS allows the eMBB UE to measure the incremental CSI-RS. The eMBB UE may derive the CSI by measuring the incremental CSI-RS and report the CSI to the gNB.

[0939] This may increase the preemptive resources for the URLLC UE. This may result in lower data communication latency performance for the URLLC UE.

[0940] The PDCCH may be configurable as resources to preempt. A method for configuring an incremental DMRS may be applied to a method for preempting a PDCCH. The supplemental PDCCH is configured when the PDCCH is configured as resources to preempt. The supplemental PDCCH may be mapped to the PDSCH region. The supplemental PDCCH may be mapped to resources along the frequency-time axes in a portion of the PDSCH region. Configuring the supplemental PDCCH allows the eMBB UE to receive the PDCCH.

[0941] This may increase the preemptive resources for the URLLC UE. For example, when data for the URLLC UE appears, the data for the URLLC UE can be transmitted without waiting for the PDCCH transmission, even with the PDCCH transmission timing. This may result in lower data latency timing for the URLLC UE.

[0942] PTRS and TRS can be used as resources for preemption or excluded from resources for preemption. Using PTRS and TRS as preemptive resources can reserve many preemptive resources for the URLLC UE. Removing PTRS and TRS from the preemption resources does not degrade the demodulation performance of the eMBB UE.

[0943] First modification of the seventh embodiment

CSI-RS are described as reference signals (RS) DL. The CSI-RSs include periodic CSI-RS for periodic CSI-RS configuration, semi-persistent CSI-RS for semi-permanent configuration of periodic CSI-RS, and aperiodic CSI-RS for aperiodic CSI-RS configuration.

[0944] The UE measures the CSI-RS to extract the CSI. The UE reports the retrieved CSI to the gNB. Methods for reporting CSI include periodic CSI reporting for periodic CSI reporting, semi-permanent CSI reporting for semi-permanent periodic CSI reporting, and aperiodic CSI reporting for aperiodic CSI reporting.

[0945] When the CSI-RS is not preempted, the data for the URLLC UE cannot be transmitted using the CSI-RS timing. Thus, the waiting time increases. To solve such a problem, the CSI-RS must be preemptive. The CSI-RS must be configurable as resources to preempt. The CSI-RS may be configurable as resources to preempt in a dedicated manner according to the CSI-RS type.

[0946] For example, periodic CSI-RS and semi-persistent CSI-RS may be configured as preemption resources, and aperiodic CSI-RS need not be configured as preemption resources.

[0947] When the CSI-RS is preempted, the UE cannot retrieve the CSI with the CSI-RS. It is not known how to report CSI in such a case. A method for solving such a problem is disclosed.

[0948] A case is disclosed where periodic CSI-RS is configured.

[0949] When the periodic CSI report is configured and the periodic CSI-RS is preempted, the periodic CSI report is not transmitted. For a periodic CSI report, a CSI report may be submitted in the next period. Thus, the CSI-RS should be measured in the next period and the result should be reported in the CSI report in the next period. Because the CSI reporting is not only provided by the timing of the preempted periodic CSI-RS, there is little impact on communication.

[0950] As an alternative method, when periodic CSI-RS is preempted, aperiodic CSI-RS transmission may be configured. The measurement result of the aperiodic CSI-RS shall be reported as CSI in the CSI report in the next period. The gNB may include aperiodic CSI-RS configuration information in the PI to notify the eMBB UE of the PI. The eMBB UE may measure the aperiodic CSI-RS.

[0951] The gNB may include information in the PI for issuing an instruction to the eMBB UE to report the aperiodic CSI-RS measurement result in a periodic CSI report to notify the eMBB UE of the PI. The eMBB UE measures the aperiodic CSI-RS with the PI and reports the result of the extracted CSI in the next periodic CSI report.

[0952] Even when channel characteristics vary, gNB can measure variations and improve communication quality.

[0953] As an alternative method, when the periodic CSI-RS is preempted, the gNB may transmit the same CSI as that in the previous periodic CSI report. When the channel time variations between the gNB and the UE are small, the CSI obtained by measuring the preempted CSI-RS is approximated to the previous periodic CSI. Thus, an approximation using the previous periodic CSI is possible. For example, when variations in channel characteristics over time between a gNB and a UE are small, such a method can be used.

[0954] When the CSI is extracted by measuring the periodic CSI-RS multiple times, the CSI can be extracted by excluding the preempted CSI-RS from the averaging process. Submission of the CSI report must be done in the CSI report. This may reduce the effect of CSI-RS, which has not been measured.

[0955] When the CSI is extracted by measuring the periodic CSI-RS several times, then the CSI can be extracted using the measurement result of the previous CSI-RS as a substitute for the preempted CSI-RS. Submission of the CSI report must be done in the CSI report. This can extract the CSI without changing the number of times the average is performed. CSI extraction processes and schema configuration can be simplified.

[0956] The above method can be applied to the method to be applied when the semi-persistent CSI report is configured and the periodic CSI-RS is preempted. This creates the same benefits.

[0957] The above method can also be applied to the method when the aperiodic CSI report is configured and the periodic CSI-RS is preempted. This creates the same benefits.

[0958] When the aperiodic CSI report is configured by extracting the CSI from the last CSI-RS, the aperiodic CSI report should not be transmitted.

[0959] The above method may be statically predefined in the standard. Since the UE and gNB can share the processing method, misoperation can be avoided. Alternatively, the gNB may notify the UE of the method via RRC signaling. The method is semi-statically configurable. For example, the method is effective when the channel characteristics vary.

[0960] Alternatively, the gNB may include a method in the PI to notify the UE of the PI. For example, the PI may include information indicating whether a CSI report is being transmitted. For example, the gNB may include information in the PI indicating that a CSI identical to a previous CSI should be reported as a CSI and notify the PI. The method for reporting CSI is dynamically configurable by including information in the PI and notification of the PI. For example, the method is effective when the channel characteristics vary in a short period of time.

[0961] The method in the case where periodic CSI-RS is configured can be applied to the case where semi-persistent CSI-RS is configured. This creates the same benefits.

[0962] When the aperiodic CSI-RS is configured, only the aperiodic CSI report is configured. In such a case, a method can be applied in which the performance of the aperiodic CSI reporting is configured by extracting the CSI from the last CSI-RS. This creates the same benefits.

[0963] When the CSI-RS is preempted, the CSI can be extracted from the measurement of the other RS. Examples of other RS may include DM-RS. The gNB notifies the UE of the configuration of the other RS. The UE measures the RS, extracts the CSI, and notifies the gNB of this result as a CSI report.

[0964] The other RS may be the RS in the slot that follows the preempted slot. RS must be used in the slot before the configured CSI report.

[0965] The gNB notifies the UE of the other RS information with the PI. Alternatively, the gNB may advertise information about the other RS via RRC signaling. Information about the additional DMRS can be used as information about the other RS.

[0966] The gNB may notify, via the PI, the UE whether a different RS is being used. Alternatively, the gNB may notify whether another RS is in use via RRC signaling. When the other RS is not used, there is no need to notify information about the other RS. Thus, the amount of information that the gNB needs to notify the UE can be reduced.

[0967] This may preempt CSI-RS. Doing the CSI-RS in a preemptive manner may result in lower communication latency performance for the URLLC UE.

[0968] The second modification of the seventh embodiment

Reference signals (RS) at UL include front loading DMRS (FL-DMRS), add-on DMRS (add-DMRS), phase tracking RS (PTRS), tracking RS (TRS), and SRS. For example, FL-DMRS appears in the first one or two symbols in PUSCH. Alternatively, FL-DMRS is displayed in the third or fourth symbol in PUSCH. PUCCH may be mapped to UL resources as a UL control channel.

[0969] A third embodiment discloses a method for symbol preemption for an eMBB UE in a UL. However, by making an arbitrary symbol for the eMBB UE preemptive, the communication quality may be degraded. A method for solving such a problem is disclosed.

[0970] When preemption is performed in the UL, preemption must be performed avoiding resources for RS and PUCCH in relation to the eMBB UE. The resources for RS and PUCCH in the UL for the eMBB UE cannot be configured as resources for UL preemption.

[0971] FIG. 53 illustrates an exemplary preemption when FL-DMRS, add-DMRS and PUCCH and/or SRS are configured for an eMBB UE. The gNB performs preemption avoiding resources for RS and PUCCH for the eMBB UE. gNB preempts some or all of the resources for PUSCH.

[0972] Symbols in which the PUSCH for the eMBB UE are mapped are pushed out as resources for the URLLC UE. The eMBB UE does not transmit using preempted resources. The eMBB UE hands over a slot (possibly a mini-slot) to the URLLC UE with preempted resources. URLLC UE performs UL transmission such as PUCCH, PUSCH and RS in a slot. gNB receives in slot eg PUCCH, PUSCH and RS from URLLC UE.

[0973] A Purge Indication (PI) is transmitted from the eMBB UE. The gNB includes in the PI information about the resources to be preempted for the eMBB UE in order to notify the eMBB UE of the PI. The method disclosed in the third embodiment can be applied to a method for notifying a PI to be used for UL preemption. Upon receiving the PI, the eMBB UE may not allow transmission with the resources to be preempted. The eMBB UE transmits, for example, PUSCH, RS, and PUCCH with resources excluding resources to be preempted. The gNB receives, for example, PUSCH, RS, and PUCCH with resources except for resources that must be preempted.

[0974] This can multiplex the UL transmission for the eMBB UE with the UL transmission for the URLLC UE. Providing early transmission for the URLLC UE may result in low latency performance. Moreover, providing a PUSCH transmission for an eMBB UE enables high-speed, high-capacity communications.

[0975] By making the symbols in which RS and PUCCH are mapped in the UL for the eMBB UE not configurable as resources for UL preemption, data transmission is disabled for the URLLC UE by the symbol timing with which the RS and PUCCH are mapped. For example, when there is data for the URLLC UE with timing, resources for the URLLC UE cannot be reserved, and thus data transmission for the URLLC UE must be delayed.

[0976] For example, since the FL-DMRS in UL consists of one or two symbols in NR, the transmission is delayed by the number of symbols. This may increase the amount of timeout in the URLLC connection of the UE. A method for solving such a problem is disclosed.

[0977] Only resources in which FL-DMRS is not displayed in symbols in which FL-DMRS is displayed can be configurable as resources to preempt. DMRS may be configured per UE per RE. In such a case, the resources to be preempted shall be REs in which FL-DMRS is not mapped. The PUSCH is transmitted in REs except for REs in which FL-DMRS is displayed, in symbols in which FL-DMRS is displayed. The PUSCH transmission area shall be configurable as resources to preempt.

[0978] The gNB includes in the PI information about the resources that must be preempted in relation to the eMBB UE in order to notify the eMBB UE of the PI. The resources to be evicted can be information specified per RE. Resources to be preempted may be configured in accordance with the above method, being specified per RE.

[0979] This can reserve resources for the URLLC UE also in symbols in which FL-DMRS is displayed. Thus, it is not necessary to delay data transmission for the URLLC UE by the number of symbols in which FL-DMRS is displayed. This can reduce the increase in the latency value in the URLLC connection of the UE.

[0980] Such a method should be applied to other RSs. Only resources that do not display RS in symbols that display RS can be configured as resources to preempt. This can create the same benefits.

[0981] Making the resources for all RS and PUCCH not configurable as resources to preempt reduces the resources for the URLLC UE. In addition, it may disable early data transmission for the URLLC UE, which increases the amount of timeout. A method for solving such a problem is disclosed.

[0982] When the add-DMRS is configured, the resources for the add-DMRS in the UL may be configurable as resources to be preempted in the UL. The eMBB UE does not transmit add-DMRS with resources for add-DMRS that are configured to preempt. Even when add-DMRS is preempted, the use of FL-DMRS by gNB may increase the likelihood of PUSCH demodulation.

[0983] FIG. 54 illustrates an exemplary preemption when FL-DMRS, add-DMRS and PUCCH and/or SRS are configured for an eMBB UE. gNB preempts resources for add-DMRS in relation to the eMBB UE.

[0984] Symbols in which add-DMRS is mapped to the eMBB UE are pushed out as resources to the URLLC UE. The eMBB UE does not transmit using preempted resources. The eMBB UE does not transmit add-DMRS. The eMBB UE transfers the slot to the URLLC UE with preempted resources. URLLC UE performs UL transmission such as PUCCH, PUSCH and RS in a slot. gNB receives in slot eg PUCCH, PUSCH and RS from URLLC UE.

[0985] Since the method for transmitting PI is identical to that in FIG. 53, its description is omitted. The eMBB UE does not send add-DMRS with preempted resources. However, since FL-DMRS is not preempted, the eMBB UE transmits FL-DMRS. Although the gNB cannot accept the preempted add-DMRS for the eMBB UE, the gNB can accept the FL-DMRS. Thus, the gNB can increase the probability of receiving data by demodulating the PUSCH with FL-DMRS.

[0986] When UL transmission from URLLC UE occurs, UL transmission from URLLC UE is provided without waiting for add-DMRS transmission. The transmission from the URLLC UE may result in lower latency performance.

[0987] When the SRS is configured, the resources for the SRS may be configurable as resources to preempt in the UL. When the resources for the SRS are configured as resources to preempt in the UL, the eMBB UE does not transmit the SRS with the configured preemption resources. The eMBB UE periodically transmits the SRS, for example, when the SRS is a periodic SRS or a semi-persistent SRS. The gNB that has configured the SRS for preemption may estimate the UL channel using the previous SRS transmitted from the UE.

[0988] Depending on the type of SRS, the resources for the SRS may be configurable as resources to be preempted in the UL. For example, when the SRS is a periodic SRS or a semi-persistent SRS, the resources for the SRS are configurable as resources to be preempted in the UL. When the SRS is an aperiodic SRS, the resources for the SRS are not configurable as resources to be preempted in the UL. This can flexibly configure preemption depending on the type of SRS.

[0989] When the PUCCH is configured as UL resources, the resources for the PUCCH may be configurable as resources for UL preemption. When the resources for the PUCCH are configured as resources to preempt in the UL, the eMBB UE does not transmit the PUCCH with the configured preemption resources. For example, when the PUCCH is a PUCCH for periodic CSI transmission, the eMBB UE periodically transmits the PUCCH. The gNB that configured the PUCCH for preemption may estimate the DL channel using the previous CSI transmitted from the UE.

[0990] Resources for PUCCH may be configurable as resources for preemption in the UL in accordance with the details of PUCCH. For example, when the PUCCH is a PUCCH for a periodic CSI or a semi-persistent CSI, the resources for the PUCCH are configurable as resources for preemption in the UL. When the PUCCH is PUCCH for an aperiodic CSI, Ack/Nack, SR, or a beam failure request, the resources for the PUCCH are not configurable as resources for preemption in the UL. It can flexibly configure preemption according to PUCCH details.

[0991] The above methods can be used in combination.

[0992] FIG. 55 illustrates an exemplary preemption when FL-DMRS, add-DMRS and PUCCH and/or SRS are configured for an eMBB UE. gNB preempts resources for PUCCH and/or SRS in relation to the eMBB UE. For example, when the PUCCH is a PUCCH for a periodic CSI or a semi-persistent CSI, the gNB may preempt resources for the PUCCH. When the SRS is a periodic SRS or a semi-permanent SRS, the gNB may preempt resources for the SRS.

[0993] Since the displacement method is identical to that of FIG. 54, its description is omitted. PUCCH and/or SRS preemption for an eMBB UE may reserve many resources for the URLLC UE. When UL transmission from URLLC UE occurs, UL transmission from URLLC UE is provided with low latency and high rates.

[0994] When FL-DMRS is configured for PUSCH, FL-DMRS may be preemptive. When FL-DMRS and add-DMRS are configured for the eMBB UE, FL-DMRS may be preemptive. FL-DMRS can be configured as resources to preempt. The eMBB UE does not transmit FL-DMRS when FL-DMRS is configured as resources for preemption.

[0995] However, since the eMBB UE configures add-DMRS, the eMBB UE transmits add-DMRS. Even when the gNB cannot receive FL-DMRS from the eMBB UE, the gNB can demodulate the data transmitted from the eMBB UE upon receiving the add-DMRS.

[0996] When only FL-DMRS is configured for PUSCH (when add-DMRS is not configured), FL-DMRS may be preemptive. FL-DMRS can be configured as resources to preempt.

[0997] Simply enabling FL-DMRS preemption may deprive the eMBB UE of the ability to demodulate PUSCH data. Some original invention is needed. The solution may be to apply the method for configuring the incremental DMRS, which is disclosed in the seventh embodiment. Although the DL add-on DMRS is disclosed in the seventh embodiment, the add-on DMRS must be properly applied to the UL configuration.

[0998] Additional DMRS is configured for the eMBB UE. The supplemental DMRS is configured in the UL region in the same slot as that of the preempted FL-DMRS and is used to demodulate the PUSCH data. When FL-DMRS is preempted, FL-DMRS cannot be used, but supplemental DMRS is used for demodulation.

[0999] The eMBB UE does not transmit data to the gNB using the resources with which the incremental DMRS was configured. The eMBB UE transmits the incremental DMRS using the resources with which the incremental DMRS has been configured. This may avoid contention between configured incremental DMRS transmission and data transmission.

[1000] If so, then the method for configuring the supplementary DMRS in DL should be properly applied to the supplementary DMRS in UL. This can create the same benefits.

[1001] FIG. 56 illustrates an example of FL-DMRS preemption when only FL-DMRS is configured in one slot for the eMBB UE. FL-DMRS is configured in one slot for the eMBB UE. The symbols in which the FL-DMRS for the eMBB UE is mapped are pushed out as resources for the URLLC UE. The eMBB UE does not transmit using preempted resources. Here, the eMBB UE does not transmit FL-DMRS. The eMBB UE transfers the slot to the URLLC UE with preempted resources. URLLC UE performs UL transmission such as PUCCH, PUSCH and RS in a slot. gNB receives in slot eg PUCCH, PUSCH and RS from URLLC UE.

[1002] gNB configures additional DMRS in the same slot. In the example, the FL-DMRS is configured as an additional DMRS being time-shifted by the symbol following the FL-DMRS, i.e. the first character is PUSCH. PUSCH does not appear on resources where incremental DMRS has been configured. The eMBB UE transmits the incremental DMRS and does not transmit the PUSCH with the resources with which the incremental DMRS has been configured.

[1003] The PI is transmitted for the eMBB UE. The gNB includes in the PI information about resources to be preempted for the eMBB UE and additional DMRS information to notify the eMBB UE of the PI. Upon receiving the PI, the eMBB UE recognizes the absence of transmission with resources to be preempted, transmits the incremental DMRS with the resources with which the incremental DMRS is configured, and recognizes the absence of transmission, for example, other channels or RS.

[1004] The eMBB UE does not transmit with the resources to be preempted, and transmits the incremental DMRS with the resources with which the incremental DMRS is configured. The gNB may accept resources for other PUSCHs except for the resources with which the incremental DMRS is configured. gNB accepts additional DMRS configured in the same slot. The gNB can demodulate the PUSCH with the optional DMRS.

[1005] If so, when UL transmission from URLLC UE occurs, UL transmission from URLLC UE is provided with low latency and at high rates, without waiting for FL-DMRS transmission even with FL-DMRS transmission timing. Since the eMBB UE transmits supplemental DMRS, the gNB can increase the probability of receiving data by demodulating the PUSCH with incremental DMRS.

[1006] It is disclosed that the eMBB UE does not transmit the SRS with the configured preemption resources when the resources for the SRS are configured as the preemption resources in the UL. Alternatively, the SRS may be configured with resources other than those for preemption. The SRS may be referred to as the accessory SRS. The method for configuring the incremental DMRS, which is disclosed in the seventh embodiment, should be properly applied to the method for configuring the incremental SRS.

[1007] When the resources for the SRS are configured as resources for preemption in the UL, the eMBB UE does not transmit the SRS, but may transmit the configured supplemental SRS using the configured resources for preemption.

[1008] When the SRS is an aperiodic SRS, the SRS is configured with the necessary timing and dynamically transmitted. For example, when an aperiodic SRS is configured as resources to preempt, the incremental SRS is configured in a different symbol. Therefore, the eMBB UE may send an additional SRS in another symbol. Thus, the gNB can receive the SRS from the eMBB UE with the necessary timing.

[1009] An incremental SRS may be configured in slot by slot that displays the SRS configured as resources to preempt. SRS is often shown in the trailing characters in a slot. For example, when such an SRS is preempted, if the timing is too late to configure the incremental SRS as UL resources in the same slot, then configuring the incremental SRS in the next slots enables the SRS to be transmitted.

[1010] FIG. 57 illustrates an exemplary preemption method when an incremental SRS is configured. Fig. 57 illustrates a case where an additional SRS is configured in a slot next to the slot with the SRS to be preempted. The SRS resources for the eMBB UE are preempted as resources for the URLLC UE in slot #1 for the eMBB UE.

[1011] The eMBB UE does not transmit using preempted resources. Here, the eMBB UE does not transmit SRS. The eMBB UE transfers the slot to the URLLC UE with preempted resources. URLLC UE performs UL transmission such as PUCCH, PUSCH and RS in a slot. gNB receives in slot eg PUCCH, PUSCH and RS from URLLC UE.

[1012] The gNB configures an additional SRS in the next slot #2. In the example, gNB configures an additional SRS in the symbol following the FL-DMRS in slot #2, i.e. the first character of PUSCH. PUSCH does not appear in the resources with which the incremental DMRS was configured. The eMBB UE transmits the incremental DMRS and does not transmit the PUSCH with the resources with which the incremental DMRS has been configured.

[1013] The PI is transmitted for the eMBB UE. The gNB includes in the PI information about resources to be preempted for the eMBB UE and additional DMRS information to notify the eMBB UE of the PI. Upon receiving the PI, the eMBB UE recognizes the absence of transmission with resources to be preempted, transmits the incremental SRS with the resources with which the incremental SRS is configured, and recognizes the absence of transmission, such as other channels or RS.

[1014] The eMBB UE does not transmit with the resources to be preempted, and transmits the incremental SRS with the resources with which the incremental SRS is configured. The gNB may accept resources for other PUSCHs, except for the resources with which the incremental SRS is configured. The gNB receives an additional SRS configured in the slot that follows the one with the SRS configured to preempt. gNB can measure the quality of the UL link using the optional SRS.

[1015] If so, when UL transmission from URLLC UE occurs, UL transmission from URLLC UE is provided with low latency and high speeds without waiting for SRS transmission even with SRS transmission timing. Since the eMBB UE transmits the incremental SRS, the gNB can increase the accuracy of UL scheduling and beam management by measuring the UL channel quality with the incremental SRS.

[1016] It is disclosed that the eMBB UE does not transmit the PUCCH with the configured preemption resources when the resources for the PUCCH are configured as the preemption resources in the UL. Alternatively, the PUCCH may be configured with resources other than those for preemption. The PUCCH may be referred to as an additional PUCCH. The method for configuring the supplemental SRS should be properly applied to the method for configuring the supplemental PUCCH. Likewise, since the gNB can receive the supplemental PUCCH transmitted from the eMBB UE, the same benefits can be generated.

[1017] FIG. 58 illustrates an exemplary preemption method when an additional PUCCH is configured. Fig. 58 illustrates the case where the supplemental PUCCH is configured in the slot following the slot with the SRS to be preempted. The PUCCH resources for the eMBB UE are preempted as resources for the URLLC UE in slot #1 for the eMBB UE.

[1018] Since the displacement method is identical to that in FIG. 57, its description is omitted. SRS must be replaced by PUCCH.

[1019] The gNB receives an additional PUCCH configured in the slot next to the one with the PUCCH configured to preempt. gNB can accept UCI from eMBB with additional PUCCH.

[1020] If so, when UL transmission from URLLC UE occurs, UL transmission from URLLC UE is provided with low latency and high rates without waiting for PUCCH transmission, even with timing of PUCCH transmission. Since the eMBB UE transmits the supplemental PUCCH, the gNB can receive the UCI from the eMBB with the incremental PUCCH and properly perform processes according to the UCI.

[1021] PTRS and TRS can be used as resources for preemption or excluded from resources for preemption. Using PTRS and TRS as preemptive resources can reserve many preemptive resources for the URLLC UE. Excluding PTRS and TRS from the preemption resources does not reduce the efficiency of gNB demodulation.

[1022] A method is disclosed for a gNB to notify an eMBB UE of resource information to be pushed to an eMBB UE and/or incremental DMRS information by a PI. The PI notification method can be applied when there is a UL data transmission request from the URLLC UE. The notification method should be applied, for example, when a URLLC UE has a UL data scheduling request (SR) or a UL data buffer status report (BSR).

[1023] Upon receipt of a UL data transmission request from the URLLC UE, the gNB notifies, via PI, the eMBB UE of resource information to be preempted in relation to the eMBB UE and/or additional DMRS information.

[1024] The method can be used in, for example, permission-based communication for transmitting UL data in a URLLC. Upon receipt of the SR from the URLLC UE, the gNB determines the resources to preempt for the URLLC UE. The gNB defines resources for the incremental DMRS when the DMRS for the eMBB UE is used as resources for preemption. The gNB notifies, via the PI, the eMBB UE of resource information to be preempted in relation to the eMBB UE and/or incremental DMRS information.

[1025] Therefore, the eMBB UE may receive information about the resources to be pushed out and/or information about the incremental DMRS.

[1026] Another method is disclosed for a gNB to notify an eMBB UE of resource information to be preempted in relation to an eMBB UE and/or additional DMRS information. gNB notifies information via RRC signaling. The gNB may notify the information in a dedicated manner to each UE or each group of UEs. Alternatively, the gNB may broadcast the information as broadcast information. The information may be broadcast information to be notified in response to a request from the eMBB UE. The gNB may notify the information in a dedicated manner to each UE in response to a request from the eMBB UE.

[1027] As described earlier in the non-granted transfer, the timing for performing the non-granted transfer is semi-statically predetermined. When the handover is configured in the URLLC, the gNB notifies the URLLC UE of the timing to perform the handover via RRC signaling. In the first ungranted transfer, the gNB notifies the resources for the ungranted transfer also via RRC signaling.

[1028] For example, in a non-granted handover, the gNB configures resources to preempt with timing to perform a non-granted handoff and a resource configuration that is configured for the URLLC UE. The gNB includes the configured resources to be pushed into the broadcast information addressed to the eMBB UE to broadcast the resources. This allows the eMBB UE to recognize the resource configuration to preempt.

[1029] gNB may configure additional DMRS. The gNB includes the configured supplemental DMRS information in the broadcast information addressed to the eMBB UE to broadcast the information. This allows the eMBB UE to recognize the incremental DMRS configuration.

[1030] Therefore, the gNB does not need to use the PI to notify resource information to be preempted in relation to the eMBB UE and/or additional DMRS information. gNB does not need to transmit PI. You do not need to reserve resources for PI. This can improve resource efficiency.

[1031] When the preempting URLLC UE is the same as the eMBB UE to be preempted, the gNB can configure resources for preemption with timing to perform unauthorized transmission and resource configuration for the URLLC, and notify the UE of the resources to preempt. The gNB may configure the incremental DMRS and notify the UE of the incremental DMRS. Because the preempting URLLC UE is the same as the eMBB UE to be preempted, the gNB can perform dedicated notification to the UE via RRC signaling, similar to timing notification to perform transmission without permission and resource configuration.

[1032] Another method is disclosed for a gNB to notify an eMBB UE of resource information to be preempted in relation to an eMBB UE and/or additional DMRS information. gNB notifies information via L1/L2 control signaling. gNB may include information in the DCI. gNB can advertise DCI using PDCCH. The gNB may notify the information in a dedicated manner to each UE or each group of UEs.

[1033] As described earlier in the non-granted transfer, the timing for performing the non-granted transfer is semi-statically predetermined. When the handover is configured in the URLLC, the gNB notifies the URLLC UE of the timing to perform the handover via RRC signaling. In the first ungranted transfer, the gNB notifies the resources for the ungranted transfer also via RRC signaling.

[1034] For example, a method using L1/L2 control signaling can be applied to an unentitled transmission. The eMBB UE is given resource information to be preempted in relation to the eMBB UE and/or supplemental DMRS information as information included in the DCI. The gNB configures the information, includes the information in the DCI, and notifies the eMBB UE of the information with the PDCCH. When incremental DMRS is not used, the gNB does not need to be notified of the incremental DMRS information. The gNB may only advertise information about resources to be preempted in relation to the eMBB UE.

[1035] Therefore, the gNB does not need to use the PI to notify resource information to be preempted in relation to the eMBB UE and/or additional DMRS information. gNB does not need to transmit PI. You do not need to reserve resources for PI. This can improve resource efficiency.

[1036] Dynamic configuration is not possible with notification via RRC signaling, as previously disclosed. Here, the gNB needs to notify the eMBB UE of resource information to be preempted and/or incremental DMRS information in a state where the eMBB of the UE to be preempted has not yet been determined. Thus, the amount of signaling for performing dedicated notification of each of the plurality of UEs is increased. Alternatively, for example, when the number of preemptive URLLC UEs increases, the broadcast information for broadcasting increases.

[1037] Notification of resource information to be preempted to the eMBB UE and/or incremental DMRS information from gNB to the eMBB UE via L1/L2 control signaling provides dynamic notification and notification to the eMBB UE to be preempted. Thus, the above problems can be solved.

[1038] In the second non-granted transmission, the gNB notifies the resource configuration for the non-granted transmission via L1/L2 control signaling. Here, resources for transmission without permission can be dynamically configured. Resources for non-granted transmission for the URLLC UE may be configured later than the PDCCH transmission timing for the eMBB UE. In such a case, the gNB cannot advertise the resource information to be preempted with the PDCCH to the eMBB UE.

[1039] When preemption is performed with a non-granted transmission to solve such a problem, the gNB needs to configure the resources for the non-granted transmission for the URLLC of the UE before the timing of the PDCCH transmission for the eMBB UE. Therefore, the gNB can advertise information about resources to be popped out with the PDCCH to the eMBB UE.

[1040] When the preemption is performed with the non-granted transmission, the first non-granted transmission may be configured. This creates the same benefits. As an alternative method, resources for non-grant transmission may be configured in advance for the case where the resource configuration for non-grant transmission for the URLLC of the UE occurs too late in relation to the timing for notifying information about resources to be pushed out with the PDCCH. for eMBB UE.

[1041] When configuring the resources for in-progress transmission with respect to the timing of the PDCCH transmission for the eMBB UE, the gNB configures the resources for the transmission without permission for the URLLC UE as resources to be preempted in relation to the eMBB UE. When resource configuration for unauthorized transmission occurs too late relative to the eMBB UE's PDCCH transmission timing, the gNB shall use the preset resource configuration for unauthorized transmission.

[1042] Therefore, when there is no information about resources to be preempted upon receipt of the PDCCH, the eMBB UE may use, as resources for preemption, a resource configuration for non-granted transmission that has been configured, for example, via RRC signaling.

[1043] According to the disclosed method, even if there is no UL transmission from a URLLC UE with resources and timing to perform an ungranted transmission, an eMBB UE for which the resources are configured as resources to preempt cannot perform a UL transmission with the resources. As resources are not used, the efficiency of resource use decreases.

[1044] A method for solving such a problem is disclosed. When the preempting URLLC UE is the same as the eMBB UE to be preempted, the UE may perform UL transmission with the resources to preempt. In the absence of UL transmission for URLLC with resources to configure transmission without permission for URLLC, when UL transmission for eMBB is scheduled in the slot for eMBB including the resources, the UE performs UL transmission for eMBB.

[1045] Because the preempting URLLC UE is the same as the eMBB UE to be preempted, the UE can recognize the absence of UL transmission with the resources with which the URLLC ungranted transmission was configured. Thus, when UL transmission for eMBB is scheduled with the resources with which the transmission without permission for URLLC has been configured, the UE performs UL transmission for eMBB.

[1046] This can improve resource efficiency.

[1047] With timing and resources to perform non-grant transmission, priorities can be assigned to UL transmission for URLLC and UL transmission for eMBB. The priorities may be assigned, for example, in accordance with the QoS or QCI required for the communication service for the URLLC. Priorities may be assigned, for example, in accordance with the desired amount of waiting time.

[1048] For example, when the amount of latency required for a communication service for URLLC is low, a priority is set for UL transmission for URLLC. Thus, the UE performs UL transmission for URLLC and does not perform UL transmission for eMBB. When the required latency amount is high, the UE may prioritize and perform UL transmission for eMBB, and need not perform UL transmission for URLLC. The indicator for prioritization may have a threshold value. For example, the latency value may have a threshold value.

[1049] The priorities may be assigned according to, for example, the QoS or QCI that is required for the communication service for the eMBB. The priorities may be assigned according to, for example, the required communication quality. Priorities may be assigned according to a desired error rate, such as a bit error rate or a frame error rate.

[1050] For example, when the bit error rate required for a communication service for eMBB is low, then a priority is set for UL transmission for eMBB. Thus, the UE performs UL transmission for eMBB and does not perform UL transmission for URLLC. When the required bit error rate is high, the UE can prioritize and perform UL transmission for URLLC, and it does not need to perform UL transmission for eMBB. For example, the bit error rate for prioritization may have a threshold value.

[1051] Priorities may be assigned according to the type of signal or channel to be displayed for eMBB. For example, when PUSCH is used for an eMBB with timing and resources to perform an unauthorized transmission, the UE prioritizes and performs a UL transmission for URLLC, and does not perform a UL transmission for the eMBB.

[1052] Priorities may be assigned according to the type of UCI included in the PUCCH to be mapped to eMBB. For example, when Ack/Nack is used for an eMBB with timing and resources to perform a non-grant transmission, the UE prioritizes and performs the UL transmission for the eMBB and does not perform the UL transmission for the URLLC.

[1053] For example, when DMRS is used for an eMBB with timing and resources to perform a grantless transmission, the UE prioritizes and performs a UL transmission for the eMBB and does not perform a UL transmission for the URLLC.

[1054] When the timing and resources to perform the non-granted transmission include DMRS for eMBB, the UE can prioritize and perform UL transmission for eMBB and does not need to perform UL transmission for URLLC. Priorities may be assigned to include part of the signals or channels for eMBB.

[1055] Priorities can be assigned with timing and resources to perform an unauthorized transmission according to the type of signal or channel to be mapped to the URLLC. For this, the same method as for eMBB can be applied.

[1056] Priority configurations may be combined. Flexible and appropriate configuration is possible according to the channel or signal on which the communication service for URLLC or UL transmission is performed, or the channel or signal on which the communication service for eMBB or UL transmission is performed.

[1057] The configuration of priorities and the information necessary for the configuration may be statically predefined, for example, in a standard. Both gNB and UE can recognize configuration and information. Misoperation can be reduced. As an alternative method, notification of the configuration of priorities and information needed for the configuration can be made from the gNB to the UE via RRC signaling or be notified in a dedicated manner for each UE. The method is semi-statically configurable. The configuration can be changed if necessary.

[1058] As an alternative method, the gNB may notify the UE of the information via MAC signaling. Early configuration is possible after notification. The information can be subjected to HARQ and receive errors can be reduced by configuring priorities. Alternatively, the gNB may notify the UE of the information via L1/L2 signaling. The gNB may include information in the DCI to notify the information using the PDCCH. Early configuration is possible after notification. Possible dynamic change or configuration.

[1059] A method is disclosed for a gNB to recognize which transmission, of a UL transmission for URLLC and a UL transmission for eMBB, has been received from a UE with resources configured to transmit without permission.

[1060] The gNB makes a determination depending on whether a DMRS has been received for URLLC. When the URLLC symbol duration is different from the eMBB symbol duration, the gNB receives the DMRS using the URLLC symbol duration and determines whether the DMRS is respectively the URLLC DMRS configured for the UE. In determining that the DMRS is the DMRS for URLLC, the gNB determines to receive the UL transmission for URLLC. Otherwise, the gNB determines the reception of the UL transmission for the eMBB.

[1061] This allows the gNB to recognize which transmission, from the UL transmission for URLLC and the UL transmission for eMBB, was received from the UE with resources configured to transmit without permission.

[1062] The DMRS for eMBB may be different from the DMRS for URLLC. gNB configures UEs with different DMRS for eMBB and for URLLC. Upon receiving the DMRS for URLLC, the gNB determines the transmission of the UL for URLLC. Otherwise, the gNB may determine the UL transfer for the eMBB.

[1063] This allows the gNB to recognize which transmission, from the UL transmission for URLLC and the UL transmission for eMBB, was received from the UE with resources configured for transmission without permission, even when the symbol duration for URLLC is exactly the same as the symbol duration for eMBB.

[1064] It is disclosed that the gNB makes a determination depending on whether a DMRS has been received for a URLLC. As an alternative method, a signal or channel indicating UL transmission for URLLC may be provided. Alternatively, a signal or channel indicating UL transmission for eMBB may be provided. A signal or channel may be provided indicating a UL transmission for URLLC or a UL transmission for eMBB.

[1065] Alternatively, information indicating UL transmission for URLLC or UL transmission for eMBB may be provided. The gNB may include the information in the UCI and transmit the UCI using the PUCCH. The information, signal, or channel may be provided as UL information, signal, or channel for URLLC, or UL information, signal, or channel for eMBB.

[1066] For example, information, signal or channel is provided as information, signal or channel UL for URLLC. When performing a UL transmission with resources configured for non-granted transmission, the UE transmits information, a signal, or a channel in a UL transmission. The gNB can recognize which transmission, from the UL transmission for URLLC and the UL transmission for eMBB, has been received from the UE depending on whether to receive information, a signal, or a channel.

[1067] For example, information, signal, or channel is provided as information, signal, or UL channel for eMBB. When performing UL transmission for eMBB with resources configured for non-grant transmission, the UE transmits information, signal or channel in UL transmission. The gNB can recognize which transmission, from the UL transmission for URLLC and the UL transmission for eMBB, has been received from the UE depending on whether to receive information, a signal, or a channel.

[1068] The timing with which the information, signal, or channel is transmitted should not be the timing of resources configured to transmit without permission. The timing may be before or after the timing of resources configured to pass without permission. The timing must be after the timing by which the gNB determines which transfer, from UL transfer for URLLC and UL transfer for eMBB, is performed with resources configured for transfer without permission.

[1069] The timing with which the information, signal, or channel is transmitted is, for example, the last symbol in a slot for eMBB. This configuration is possible wherever an eMBB slot is transmitting for URLLC. Alternatively, the timing at which the information, signal or channel is transmitted is the first symbol in the next eMBB slot. This can create the same benefits. The gNB may configure for the UE in advance the timing with which the information, signal, or channel is transmitted, and notify the UE of the timing.

[1070] The configuration of the information, signal, or channel, or the timing with which the information, signal, or channel is transmitted, may be predetermined, for example, in a standard. Both gNB and UE can recognize configuration and timing.

[1071] The configuration for the incremental DMRS, which is disclosed in the second modification, may be statically predefined, for example, in the standard. Both gNB and UE can recognize the configuration. This should be applied, for example, when the RS is preempted and then shifted such that an additional DMRS is configured. For example, when the FL-DMRS is preempted, the FL-DMRS is shifted such that an additional DMRS is configured. The character to be shifted is predefined in the standard. The information that is needed to configure an incremental DMRS is predefined in the standard. This may eliminate the need for notification of extension DMRS information and reduce the amount of information required for signaling.

[1072] Third modification of the seventh embodiment

In grant-based (GB) communications for UL data transmission, the UE requests an uplink grant by transmitting an SR to a gNB. The SR is mapped to the PUCCH to be transmitted. Communication that requires high reliability, such as URLLC, requires not only improving the reliability of data transmission, but also improving the reliability of the SR.

[1073] Retransmission of the PUCCH including the SR is performed to improve the reliability of the SR. Retransmission of the PUCCH including the SR may improve the communication quality of the SR and improve the reliability of the SR. PUCCH retransmission includes a method for retransmitting the PUCCH in one symbol twice. PUCCH retransmission also includes a method for retransmitting in multiple slots a PUCCH consisting of three or more symbols.

[1074] When transmitting an SR after transmitting an SR, an SR prohibit timer is configured. After the transmission of an SR, transmission of a new SR is prohibited for the duration until the timer expires. When the timer expires, the transmission of a new SR is allowed.

[1075] It is not known how to handle the SR prohibit timer when SR retransmission is configured. In the case where it is not known how to handle the SR prohibit timer, operational inconsistencies between the gNB and the UE may cause misoperation. A method for solving such a problem is disclosed.

[1076] Retransmission of an SR to be transmitted while the SR prohibition timer after SR transmission is enabled is enabled. This may avoid the failure to perform SR retransmission due to the SR prohibit timer. This enables the retransmission of the SR and may improve the reliability of the SR.

[1077] When transmitting an SR, a limit is imposed on the maximum number of SR transmissions. The SR is transmitted with a period configured for the SR until an uplink grant is received, including the transmission of the first SR. The number of SR gears is limited.

[1078] It is not known how to handle the maximum number of SR transmissions when SR retransmission is configured. In the case where it is not known how to handle the maximum number of SR transmissions, operational inconsistencies between the gNB and the UE may cause misoperation. A method for solving such a problem is disclosed.

[1079] The number of SR retransmissions is not counted to limit the maximum number of SR transmissions after SR transmission. Therefore, a limit on the maximum number of transmissions is imposed by the number of SR transmissions with a period configured for the SR, as is done normally. This can avoid reaching the maximum number of SR transmissions in a short period of time and improves the reliability of the SR.

[1080] As an alternative method, the number of SR retransmissions is counted to limit the maximum number of SR transmissions after SR transmission. Therefore, a limit on the maximum number of transmissions is imposed by the number of SR transmissions including the number of SR retransmissions. Thus, when the limit on the maximum number of SR transmissions is reached, the process shifts to the next process. The duration between processes can be shortened. For example, when the channel quality is lower, the process may be shifted to the next process earlier. Thus, the waiting time required for a process can be shortened. On the other hand, since the maximum number of SR transmissions is exactly the same as usual, reliability can be obtained as usual.

[1081] Whether the number of SR retransmissions is counted to limit the maximum number of SR transmissions after SR transmission may be statically predetermined in the standard. Alternatively, the gNB may semi-statically configure for the UE whether to count the number of SRs to limit the maximum number of SRs after an SR has been transmitted. The gNB may notify the UE whether to count the number of SRs to limit the maximum number of SRs after an SR is transmitted through RRC signaling or notify each UE in a dedicated manner. The gNB may advise whether to count the number of SR retransmissions to limit the maximum number of SR transmissions after an SR is transmitted, along with the SR configuration or PUCCH configuration to be used for the SR.

[1082] This can reduce misoperation caused by inconsistencies in operation between the gNB and the UE during SR transmission and improve the reliability of the SR.

[1083] For example, a service such as URLLC requires low latency characteristics. UL preemption communication is supported to achieve low latency performance in UL. In UL preemption communication, UL data communication with GB requires high SR reliability. A method for solving such a problem is disclosed.

[1084] Enable preemption for SR. The resources for the eMBB UE are preempted and the SR for the URLLC UE is transmitted. The PUSCH and/or RS and/or PUCCH for the eMBB UE are preempted and the SR is transmitted for the URLLC UE. gNB configures SR for URLLC UE. gNB can configure retransmissions as SRs. The gNB preempts resources for the eMBB UE with the SR resources configured for the URLLC UE.

[1085] The eMBB UE does not transmit using preempted resources. When uplink URLLC data appears, the UE transmits the SR with the resources of the configured SR. The gNB notifies the UE of the SR configuration for the UE's URLLC or PUCCH for SR transmission via RRC signaling. The SR for a URLLC UE or the PUCCH for SR transmission may be a PUCCH consisting of one or two symbols, or a PUCCH consisting of three or more symbols.

[1086] The problem is how the eMBB UE recognizes the resources in which the PUCCH is mapped, transmitting the SR for the URLLC UE. A method for solving such a problem is disclosed. The gNB shall notify the eMBB UE of the PUCCH configuration for SR transmission for the URLLC UE. The notification method may be RRC signaling. The PUCCH configuration may be broadcast to transmit the SR to the URLLC of the UE as broadcast information, or may be notified in a dedicated manner to each UE.

[1087] The eMBB UE does not transmit with resources that map the configured PUCCH for SR transmission. This may avoid contention between the SR transmission from the URLLC UE and the transmission from the eMBB UE. The reliability of the SR transmission from the URLLC UE can be improved.

[1088] When notifying the eMBB UE of the PUCCH configuration for transmitting the SR for the URLLC UE, the gNB needs to notify the eMBB UE of the configuration in advance. At the time of notification, it is not known which eMBB UE is scheduled in the slot that includes the resources with which the PUCCH was configured to transmit the SR for the URLLC UE.

[1089] While it is possible for a gNB to notify all eMBB UEs it serves, this reduces radio resource efficiency because the resources required for notification are huge. A method for solving such a problem is disclosed.

[1090] The PI method is applied as a method for the gNB to notify the eMBB UE of the PUCCH configuration for SR transmission for the URLLC UE. The PI must include PUCCH information for transmitting the SR for the URLLC UE. The supplemental DMRS information which is disclosed in the seventh embodiment should be properly applied to the PUCCH information for transmitting an SR for a URLLC UE. The PUCCH to transmit the SR for the URLLC UE may be used in place of the supplemental DMRS.

[1091] If so, then notifying the eMBB UE of the PUCCH configuration for SR transmission to the URLLC UE by PI may limit the eMBB UEs to be notified to the eMBB UEs scheduled in the slot in which the PUCCH for SR transmission is mapped. Thus, the resources required for notifying the eMBB to the UE can be reduced and the radio resource utilization efficiency can be improved.

[1092] FIG. 59 illustrates an example of configuring wipe for SR. The characters in which PUSCH is displayed for the eMBB UE are pushed out as resources for the URLLC UE. The eMBB UE does not transmit using preempted resources. Here, the eMBB UE does not transmit PUSCH. The eMBB UE hands over a slot (possibly a mini-slot) to the URLLC UE with preempted resources. URLLC UE transmits SR in slot. In other words, the URLLC UE transmits the PUCCH for the SR in the slot. gNB receives SR from URLLC UE in slot.

[1093] Although the transmission of a slot for a URLLC UE using preempted resources has been described above, one or more characters for a URLLC UE may be transmitted instead of a slot. The method can be applied when the PUCCH for the SR is mapped not in a slot, but in one or more symbols. URLLC UE transmits SR in symbols. The gNB receives the SR from the URLLC UE in symbols.

[1094] The PI is transmitted for the eMBB UE. The gNB includes in the PI information about the resources to be popped out for the eMBB UE to notify the eMBB UE of the PI. The resource information to be preempted may be, for example, PUCCH information for transmitting an SR for a URLLC UE. Upon receipt of the PI, the eMBB UE recognizes that there is no transmission with resources to be preempted and that there is no PUSCH transmission.

[1095] The eMBB UE does not transmit using preempted resources. gNB may accept resources for other PUSCHs.

[1096] If so, when the UL transmission from the URLLC UE occurs, the SR can be transmitted from the URLLC UE with low latency without waiting for the eMBB UE transmission, even with the timing of the eMBB UE transmission. The transmission of the SR from the URLLC UE with low latency allows the URLLC UE to receive the UL grant from the gNB earlier and transmit the UL data to the gNB earlier. Thus, the URLLC UE can perform UL communication in low latency.

[1097] The disclosed method for preempting resources for an eMBB UE for transmitting URLLC UE data should be properly applied to a method for preempting resources for an eMBB UE for PUCCH for transmitting an SR for a URLLC UE. For example, the method disclosed in the second modification of the seventh embodiment should be properly applied. This can create the same benefits.

[1098] For example, configuring FL-DMRS for the eMBB UE as resources to preempt and configuring the DMRS can avoid degradation of demodulation performance in the eMBB UE and perform UL communication for the URLLC UE with low latency.

[1099] While a method for pushing resources for an eMBB UE to transmit an SR for a URLLC UE has been disclosed above, another method for enabling SR transmission for a URLLC UE with resources for an eMBB UE is disclosed below.

[1100] When the SCS and symbol duration for the URLLC UE are exactly the same as those for the eMBB UE, the SR for the URLLC UE is multiplexed with the resources in which the DMRS for the eMBB UE is mapped. The multiplexing method should be code multiplexing with DMRS for the eMBB UE. Various orthogonal codes may be used. The SR configuration for the URLLC UE may be identical to that of the DMRS for the eMBB UE.

[1101] The gNB must notify the UE in advance of the SR configuration for the URLLC of the UE to be multiplexed with DMRS for the eMBB UE. Configuration notification may be via RRC signaling or via DCI. Possible dynamic notification. Therefore, the DMRS for the eMBB UE may be multiplexed with the SR for the URLLC UE. The gNB may receive the DMRS transmitted from the eMBB UE and the data transmitted from the URLLC UE. Since the gNB may receive URLLC UE data earlier, this may result in low latency performance in URLLC UE communications.

[1102] Fourth modification of the seventh embodiment

In NR grant-based communication, downlink data or uplink data may be configured to be retransmitted over multiple slots. In non-granted communication in NR, uplink data may be configured to be retransmitted over multiple slots.

[1103] When multi-slot retransmission (possibly mini-slots) is configured for the URLLC UE, URLLC UE retransmission may be performed per slot for the eMBB UE. The conventional preemption method is a method for preempting one contiguous resource upon the occurrence of a data transmission for a URLLC UE in one slot for an eMBB UE. Thus, UE URLLC retransmission preemption by slots is not possible with an eMBB UE. A method for solving such a problem is disclosed.

[1104] When resources for the eMBB UE are multiplexed with resources for the URLLC UE, data retransmission for the URLLC UE cannot be configured. When preemptive communication is configured in communication for eMBB UE and communication for URLLC UE, data retransmission for URLLC UE is made non-configurable. This may contribute to the displacement process.

[1105] Another method is disclosed. When resources for the eMBB UE are multiplexed with resources for the URLLC UE, data retransmission for the URLLC UE may be configured. When preemptive communication is configured in communication for eMBB UE and communication for URLLC UE, retransmission of data for URLLC UE can be configured.

[1106] Since this enables retransmission of data for the URLLC UE, the reliability of the communication for data transmission for the URLLC UE can be improved. The data link coverage for the URLLC UE may be extended.

[1107] The gNB must configure the number of retransmissions. For example, the gNB must configure the number of retransmissions to avoid spreading over any slots for the eMBB UE. gNB must configure the number of transmissions that can be repeated in one slot. The gNB may configure the number of retransmissions such that a signal or channel for the eMBB UE that is not configurable as resources to preempt does not compete with data retransmissions for the URLLC UE. This can be applied to a retransmission configuration within a single slot.

[1108] This may contribute to the process of displacement. Since retransmission can be configured in communication for the URLLC UE, reliability is improved.

[1109] The gNB may notify the URLLC UE of the retransmission number configuration via L1/L2 control signaling. The gNB may include the configuration in the DCI and advertise the DCI using the PDCCH. The number of retransmissions may be dynamically configured according to the slot configuration of the eMBB UE.

[1110] The configuration about the number of retransmissions can be made different in the presence and absence of multiplexing of resources for eMBB UE with resources for URLLC UE. The gNB may configure the number of retransmissions for the URLLC UE multiple times. The gNB may notify via RRC signaling. The gNB may select one of a variety of configurations and notify the selected URLLC configuration to the UE. The gNB may notify via L1/L2 control signaling. The gNB can include the configuration in the DCI and notify the DCI with the PDCCH.

[1111] The number of repetitions may be dynamically configured in accordance with the presence or absence of resource multiplexing for the eMBB UE.

[1112] Disclosed is a method for preempting data retransmission for a URLLC UE over slots for an eMBB UE.

[1113] Disclosed method of displacement in the DL. Data preemption for URLLC UE is not performed with resources that map PDCCH and FL-DMRS for eMBB UE. Data retransmission for the URLLC UE is scheduled on resources that do not map PDCCH and FL-DMRS to the eMBB UE. This allows the eMBB UE to receive PDCCH and FL-DMRS. Upon receiving the PDCCH and FL-DMRS, the eMBB UE may receive the PDSCH data.

[1114] FIG. 60 illustrates an exemplary method for preempting data retransmission for URLLC UEs over slots for eMBB UEs. It is assumed that the number of per-unit data transmissions for the URLLC UE is two. Resources for the eMBB UE are pushed out for the first data link at the URLLC UE in slot #1 for the eMBB UE. Typically, the gNB transmits the second data for the URLLC UE in the next slot for the URLLC UE.

[1115] However, in the displacement, as illustrated in FIG. 60, the slot for the first data link of the URLLC UE is followed by resources in which the PDCCH and FL-DMRS for the eMBB UE are mapped. Thus, the slot for the URLLC UE cannot be reserved during this. The slot for the second URLLC data of the UE is configured in the symbol after the FL-DMRS in slot #2 for the eMBB UE, and is preempted.

[1116] The repeated data for the URLLC UE is transmitted in the slot for the URLLC UE, which is preempted in slot #2 for the eMBB UE.

[1117] The PI is transmitted for the eMBB UE. The gNB includes in the PI information about resources to be preempted in slot #1 and slot #2 for the eMBB UE to notify the eMBB UE of the PI.

[1118] This enables the preemption process even when retransmission is configured for the URLLC UE. Therefore, retransmission for the URLLC UE can be performed with low latency, and high reliability and low latency performance can be obtained in communication for the URLLC UE.

[1119] FIG. 60 illustrates that data retransmission for the URLLC UE is not performed with resources that map the PDCCH and FL-DMRS for the eMBB UE. When other channels or RSs are displayed, data retransmission for the URLLC UE does not need to be performed with some or all of the resources for those channels or RSs. This may reduce the impact on communication for the eMBB UE.

[1120] Data retransmission for URLLC UE may be scheduled on resources for FL-DMRS for eMBB UE. In other words, data retransmission for the URLLC UE is not performed with the resources in which the PDCCH is mapped for the eMBB UE. Data retransmission for the URLLC UE is scheduled on the resources in which the PDCCH for the eMBB UE is mapped.

[1121] In such a case, the eMBB UE has a problem that it is unable to receive FL-DMRS. The method disclosed in the seventh embodiment is to be applied to a method for solving such a problem. It can create the same benefits. Because the resources for FL-DMRS can be configured as resources to preempt, the data for the URLLC UE can be reported earlier with low latency.

[1122] FIG. 61 illustrates an exemplary method for preempting data retransmission for a URLLC UE across slots for an eMBB UE. It is assumed that the number of data retransmissions for the URLLC UE is three. Fig. 61 illustrates the case where the FL-DMRS for the eMBB UE runs configurable as resources to preempt.

[1123] In slot #1 for the eMBB UE, resources on which the PDSCH for the eMBB UE is mapped are preempted for the first and second URLLC data links of the UE. Typically, the gNB transmits the third data for the URLLC UE in the next slot for the URLLC UE.

[1124] When evicting, as illustrated in FIG. 61, the slot for the second URLLC data link of the UE is followed by resources in which the PDCCH for the eMBB UE is mapped. Thus, the slot for the URLLC UE cannot be reserved during this. The PDCCH for the eMBB UE is followed by FL-DMRS and FL-DMRS is configured as resources to preempt. The URLLC third data slot of the UE is configured in FL-DMRS in slot #2 for the eMBB UE and is preempted.

[1125] The repeated data for the URLLC UE is transmitted in the slot for the URLLC UE, which is preempted in slot #2 for the eMBB UE.

[1126] Because FL-DMRS is preempted in slot #2 with respect to the eMBB UE, the eMBB UE cannot demodulate the data in slot #2 as is. Thus, the method for configuring the incremental DMRS as disclosed in the seventh embodiment is applied. On FIG. 61 applies a method for shifting the FL-DMRS after the resources are being pushed out.

[1127] Since this configures the DMRS after the resources pushed out for the third link to transmit URLLC UE data, the eMBB UE can demodulate the data in slot #2.

[1128] The PI is transmitted for the eMBB UE. The gNB includes in the PI information about resources to be preempted in slot #1 and slot #2 for the eMBB UE to notify the eMBB UE of the PI.

[1129] When the resources to be preempted for the first UE URLLC data and the resources to be preempted for the second UE URLLC data are contiguous, the resources may be separate pieces of information or information in one contiguous resource.

[1130] Because this can make FL-DMRS for the eMBB UE configurable for preemption, retransmission for the URLLC UE can be performed with low latency. Therefore, retransmission for the URLLC UE can be performed with low latency, and high reliability and low latency performance can be obtained in communication for the URLLC UE.

[1131] When the PDCCH and/or FL-DMRS resources for the eMBB UE are made non-configurable as resources to preempt, retransmission for the URLLC UE cannot be performed in consecutive slots for the URLLC UE. For example, in FIG. 60, the first transmission and the second retransmission for the URLLC UE are discretely mapped with resources for the PDCCH and FL-DMRS for the eMBB UE placed between them.

[1132] A scheduling method in such a case is disclosed. The gNB notifies the URLLC UE of the retransmission to be performed in discrete slots. The gNB notifies information about the discrete slots in which the retransmission is performed. gNB notifies, for example, of slot numbers where transmission is not possible. The gNB notifies the number of retransmissions or the number of slots in which the retransmission is performed. Therefore, the URLLC UE can receive as many times as the number of repetitions in slots except slots in which transmission is not possible. Slot numbers in which transmission is not possible may be consecutive or non-consecutive. A plurality of slot numbers in which transmission is not possible can be configured.

[1133] Slot numbers in which transmission is not possible can be configured within a predetermined duration. Examples of the predetermined duration include the radio frame duration of the URLLC UE and the one slot duration of the eMBB UE. gNB notifies the UE of the configuration.

[1134] The gNB may configure for the UE at predetermined intervals. The gNB notifies the UE of the configuration at predetermined intervals. For example, the gNB may perform configuration when the slot configuration of the eMBB UE changes over time and the symbols in which the PDCCH or FL-DMRS is mapped change.

[1135] The same configuration may be repeated at predetermined intervals. Repetitions of the same configuration may be statically predefined, for example in a standard. The gNB needs to notify the URLLC UE of the configuration only once, which may reduce the amount of information required for notification.

[1136] Another method is disclosed. gNB notifies, for example, the slot numbers in which transmission is possible. gNB notifies the number of retransmissions or the number of slots in which the retransmission is performed. Therefore, the URLLC UE may receive as many times as the number of repetitions in the slots in which transmission is possible. The slot numbers in which transmission is possible may or may not be consecutive. A plurality of slot numbers in which transmission is possible can be configured.

[1137] The slot numbers in which transmission is possible can be configured within a predetermined duration. The disclosed method can be applied to a method for configuring, within a predetermined duration, slot numbers in which transmission is possible. This creates exactly the same benefits.

[1138] A method for configuring slot numbers in which transmission is not possible may be combined with a method for configuring slot numbers in which transmission is possible. Slots within a predetermined duration and information indicating whether transmission is possible may be represented in a bitmap as a configuration method. For example, assuming that "0" represents that transmission is not possible and "1" represents that transmission is possible, a bitmap is configured with as many bits as there are slots within a predetermined duration. The gNB must notify the URLLC UE of the bitmap. The amount of information can be reduced more than that for notifying slot numbers.

[1139] The gNB may notify the UE of resource multiplexing for the eMBB UE. The gNB may advertise the subcarrier spacing (SCS) or symbol duration of the resources to be multiplexed. Notification of the SCS or symbol duration allows the URLLC UE to recognize in which slot retransmission may not be possible. Retransmission must be made impossible in a slot in which retransmission may not be possible.

[1140] The gNB may notify the UE via RRC signaling of information about discrete slots in which retransmission is performed. This is effective when a semi-static configuration is performed. gNB can advertise the information via MAC signaling. This is effective when the configuration changes dynamically. Receive errors are reduced by applying retransmission. Thus, misoperation caused by inconsistencies between gNB and UE is unlikely to occur.

[1141] The DCI may include information about discrete slots in which retransmission is performed. gNB can advertise DCI via L1/L2 control signaling. This is effective when the configuration changes dynamically. Since the configuration can be changed earlier, the appropriate configuration for, for example, a radio propagation situation and a resource usage state can be more flexibly configured.

[1142] RRC signaling, MAC signaling, and L1/L2 control signaling may be used in combination. The gNB may notify, for example, the number of retransmissions or the number of slots in which retransmission is performed through RRC signaling, and information indicating whether transmission is possible in slots within a predetermined duration through L1/L2 control signaling. The combined use of signaling for notification provides configuration and notification according to the frequency of configuring pieces of information.

[1143] In NR, a slot including symbols less than 14 is supported. A slot is also referred to as a non-slot or a mini-slot. When mini-slots are used, the number of mini-slots must be configured. Disclosed is a method for assigning slot numbers to mini-slots. Slot numbers must be assigned that are consecutive within a predetermined duration. Examples of the predetermined duration include one slot and a radio frame.

[1144] As a method for assigning slot numbers for mini-slots, an additional number to the slot number may be assigned. When the slot number is 1, the slot numbers of the mini-slots configured in the slot may be 11, 12, and 13, for example. The slot number and the mini-slot number may be configured by a plurality of bits. The slot number and the mini-slot number may be configured by bits representing the slot number and bits representing the mini-slot number. For example, suppose using four bits that the first two bits represent the slot number and the last two bits represent the mini-slot number. For example, when the slot number is 1 and the mini slot number is 3, "0111" is used.

[1145] Therefore, when a mini-slot is used, the mini-slot can be identified by a number.

[1146] When mini-slots are used for the URLLC UE, information about the discrete slots in which retransmission is performed for the URLLC UE may be mini-slot information, for example. The information must be configured using mini-slot numbers. The URLLC UE may perform retransmissions as many times as the number of repetitions in the mini-slots where transmission is possible.

[1147] Disclosed is a method for notifying an eMBB UE of resources to preempt. The gNB notifies, via PI, the eMBB UE of resource information to preempt for retransmissions, including the first transmission of the URLLC UE.

[1148] When UE URLLC retransmissions are performed across multiple slots for the eMBB UE, for example, PI is provided with inter-slot timing. The gNB notifies, via inter-slot timing PI, the eMBB UE of the resources to preempt in each of the slots. This can reduce the amount of information that must be included in each PI. The eMBB UE should receive the inter-slot timing-transmitted PI in the slot that was scheduled for its own UE.

[1149] As an alternative method, multi-slot preemption resource information is included in, for example, a timing PI between the first slots. The gNB notifies the eMBB UE, via timing PI between the first slots, of the resources to preempt in each of the slots. Therefore, the eMBB UE only needs to receive the PI transmitted with timing between the first slots, which can facilitate the reception process and reduce power consumption.

[1150] Disclosed method of displacement in the UL. Data retransmission for the URLLC UE is not performed with resources that map RS and PUCCH for the eMBB UE. Data retransmission for the URLLC UE is scheduled on resources that do not map RS and PUCCH to the eMBB UE. This allows the eMBB UE to transmit RS and PUCCH. Upon receiving the RS and PUCCH, the gNB can communicate for data transmission, including retransmission.

[1151] FIG. 62 illustrates an exemplary method for preempting data retransmission for URLLC UEs over slots for eMBB UEs. The number of data retransmissions for a URLLC UE is assumed to be two. Resources for the eMBB UE are preempted for the first URLLC data link of the UE in slot #1 for the eMBB UE. Typically, the URLLC UE transmits the second data to the URLLC UE in the next slot to the URLLC UE.

[1152] However, when preempted, as illustrated in FIG. 62, the slot for the first URLLC data link of the UE is followed by resources in which PUCCH/SRS and FL-DMRS for the eMBB UE are mapped. Thus, the slot for the URLLC UE cannot be reserved during this. The slot for the second URLLC data of the UE is configured in the symbol after the FL-DMRS in slot #2 for the eMBB UE, and is preempted.

[1153] The repeated data for the URLLC UE is transmitted in the slot for the URLLC UE, which is preempted in slot #2 for the eMBB UE.

[1154] The PI is transmitted for the eMBB UE. The gNB includes in the PI information about resources to be preempted in slot #1 and slot #2 for the eMBB UE in order to notify the eMBB UE of the PI.

[1155] The PI may be provided with inter-slot timing. The gNB notifies, via inter-slot timing PI, the eMBB UE of the resources to preempt in each of the slots. This may reduce the amount of information that must be included in each PI. The eMBB UE may receive a PI to be timed transmitted between slots in a slot that has been scheduled for its own UE.

[1156] This enables the preemption process even when retransmission is configured for the URLLC UE. Therefore, retransmission for the URLLC UE can be performed with low latency, and high reliability and low latency performance can be obtained in communication for the URLLC UE.

[1157] Retransmission of data for URLLC UE can be performed with resources that map RS or PUCCH except for FL-DMRS for eMBB UE. Data retransmission for URLLC UE is scheduled per resource except for FL-DMRS for eMBB UE. This provides early data transmission for the URLLC UE. Since the eMBB UE can transmit FL-DMRS, the gNB can receive data using FL-DMRS.

[1158] When the resources for FL-DMRS for the eMBB UE are made non-configurable as resources for preemption, retransmission for the URLLC UE cannot be performed in consecutive slots for the URLLC UE. For example, the first transmission and the second retransmission for the URLLC UE are discretely mapped with the resources for FL-DMRS for the eMBB UE in between.

[1159] The above method regarding DC should be properly applied to such a scheduling method. Handover from gNB to UE in DL should correspond to handover from UE to gNB in UL.

[1160] Data retransmission for URLLC UE may be scheduled on resources for FL-DMRS for eMBB UE. In such a case, the eMBB UE has a problem that it is unable to transmit FL-DMRS. The method disclosed in the second modification of the seventh embodiment is to be applied to a method for solving such a problem. This can create the same benefits. Because the resources for FL-DMRS can be configured as resources to preempt, the data for the URLLC UE can be reported earlier with low latency.

[1161] FIG. 63 illustrates an exemplary method for preempting data retransmission for URLLC UEs over slots for eMBB UEs. The number of data retransmissions for a URLLC UE is assumed to be two. Fig. 63 illustrates the case where the FL-DMRS for the eMBB UE runs configurable as resources to preempt.

[1162] In slot #1 for the eMBB UE, the resources on which the PUSCH for the eMBB UE is mapped are preempted for the first URLLC data link of the UE. Typically, the URLLC UE transmits the second data to the URLLC UE in the next slot to the URLLC UE.

[1163] When displacing, as illustrated in FIG. 63, the slot for the first URLLC data link of the UE is followed by resources in which the PUCCH is mapped to the eMBB UE. Thus, the slot for the URLLC UE cannot be reserved during this. The PUCCH for the eMBB UE is followed by FL-DMRS and FL-DMRS is configured as resources for preemption. The slot for the second URLLC data of the UE is configured in FL-DMRS in slot #2 for the eMBB UE, and is preempted.

[1164] The repeated data for the URLLC UE is transmitted in the slot for the URLLC UE, which is preempted in slot #2 for the eMBB UE.

[1165] Since FL-DMRS is preempted in slot #2 for the eMBB UE, the gNB cannot demodulate the data in slot #2 as is. Thus, the method for configuring the incremental DMRS as disclosed in the second modification of the seventh embodiment is applied. On FIG. 63 applies a method for shifting the FL-DMRS after the resources are being pushed out. The eMBB UE transmits incremental DMRS after the resources being preempted.

[1166] Since this configures the DMRS after the resources pushed out for the UE's second URLLC data link, the gNB can demodulate the data in slot #2.

[1167] The PI is transmitted for the eMBB UE. The gNB includes in the PI information about resources to be preempted in slot #1 and slot #2 for the eMBB UE to notify the eMBB UE of the PI.

[1168] When the resources to be evicted for the first URLLC UE and the resources to be evicted for the second URLLC UE are contiguous, the resources may be individual pieces of information or information on a single contiguous resource.

[1169] Because this can make FL-DMRS for the eMBB UE configurable for preemption, retransmission for the URLLC UE can be performed with low latency. Therefore, retransmission for the URLLC UE can be performed with lower latency, and high reliability and low latency performance can be obtained in communication for the URLLC UE.

[1170] A preemption method is disclosed when retransmission for a URLLC UE is performed per slot for an eMBB UE. The method is to be applied to preemption when one slot includes symbols in which preemption is not possible without spreading by slots, and retransmission is performed by symbols. Although slot number information is required per slot, slot number information may not be needed without extension per slot.

[1171] Because this allows the UE's URLLC to be retransmitted even if there is a certain symbol in which preemption is not possible, high reliability and low latency communication is possible. Conversely, for example, a symbol in which preemption is not possible may be configured in one slot for the eMBB UE. The flexible slot format may be configured according to, for example, a communication service, a required QoS, or a radio propagation environment.

[1172] Fifth modification of the seventh embodiment

When preemption is not possible in the symbols in which the PDCCH is displayed for the eMBB in the DL and data is transmitted to the URLLC UE, scheduling for the URLLC UE cannot be performed during the symbols in which the PDCCH is displayed. Thus, the waiting time in transmission to the URLLC UE is increased. A method for solving such a problem is disclosed.

[1173] The PDCCH for the eMBB UE is multiplexed with the preemption resources for the URLLC UE in the symbols in which the PDCCH is mapped. A multiplexing method is disclosed. In the symbols in which the PDCCH for the eMBB UE can be mapped, the resources for the URLLC UE are mapped to the resources in which the PDCCH for the eMBB UE is not actually mapped.

[1174] In other words, the PDCCH for the eMBB UE is frequency division multiplexed and/or time division multiplexed with resources for the URLLC UE in symbols on which the PDCCH for the eMBB UE can be mapped. In symbols in which the eMBB UE PDCCH may be mapped, the eMBB UE PDCCH may not necessarily be mapped in all REs. There may be some REs that do not map the PDCCH to the eMBB UE. Resources for the URLLC UE must be scheduled using some or all of the REs in which the PDCCH for the eMBB UE is not mapped.

[1175] The gNB does not notify the eMBB UE of resources to preempt. Because the REs that map the PDCCH to the eMBB UE are not preempted, the gNB can map the PDCCH to the eMBB UE, and the eMBB UE can receive the PDCCH even if there is no resource notification to preempt.

[1176] The problem is the way for gNB to perform scheduling for URLLC UE. A Control Resource Set (CORESET) is configured for the URLLC UE in the PDCCH multiplex slot for the eMBB UE. CORESET is periodically configured with resources to which the PDCCH can be mapped. CORESET is configured per UE or per group of UEs. The CORESET for each UE group may be referred to as common to the CORESET group.

[1177] CORESET may be configured for the PDCCH for the eMBB UE. The gNB shall configure CORESET for the eMBB UE and CORESET for the URLLC UE without any contention between them. Therefore, the gNB may multiplex the PDCCH for the URLLC UE with the symbols in which the PDCCH for the eMBB UE is mapped to transmit the resulting signal.

[1178] The gNB transmits data scheduling information for the URLLC UE using the PDCCH. Upon finding its own PDCCH in the CORESET resources, the URLLC UE may receive DCI and data scheduling information for its own UE. The URLLC UE receives data according to the scheduling information.

[1179] Therefore, the URLLC UE may receive data for the URLLC UE in symbols in which the PDCCH is mapped to the eMBB UE.

[1180] A set of CORESETs may be configured for the UE. CORESET may be separately provided in resources in which the PDCCH for the eMBB UE is multiplexed with the PDCCH for the URLLC UE. The resources that map the PDCCH to the eMBB UE on the resources they are not multiplexed with may be made different from the resources that map the PDCCH to the eMBB UE on the resources they are multiplexed with.

[1181] Resources that map the PDCCH to the URLLC UE on the resources they are not multiplexed with may be made different from the resources that map the PDCCH to the URLLC UE on the resources they are multiplexed with. Accordingly, CORESETs may be differently configured between resources with which they are multiplexed and resources with which they are not. This can increase resource efficiency.

[1182] FIG. 64 illustrates a method for multiplexing a PDCCH for an eMBB UE with a slot (possibly a mini-slot) for a URLLC UE. The PDCCH and data for the URLLC UE are mapped in symbols in which the PDCCH for the eMBB UE can be mapped. gNB configures in symbols in which PDCCH for eMBB UE, CORESET for eMBB UE and CORESET for URLLC UE can be mapped without any contention between them.

[1183] Therefore, the gNB can multiplex the PDCCH for the URLLC UE with symbols in which the PDCCH for the eMBB UE is mapped to transmit the resulting signal.

[1184] The gNB may configure a CORESET for the URLLC of the UE, for symbols in which the PDCCH for the eMBB UE may be mapped. The PDCCH for the eMBB UE is mapped in predefined symbols from the start of the slot. Thus, the periodic configuration can be performed in accordance with the symbols.

[1185] For example, upon the appearance of data for the URLLC UE, and even in the presence of symbols in which the PDCCH for the eMBB UE is transmitted with data timing, the PDCCH and data for the URLLC UE can be transmitted in symbols without failing to transmit the PDCCH for the eMBB UE.

[1186] Providing an earlier transmission for the URLLC UE may result in low latency performance. Since the PDCCH for the eMBB UE can also be transmitted, communication for data transmission at the eMBB UE is possible. Thus, high-speed, high-capacity communication is possible.

[1187] When retransmission is configured for the URLLC UE, the scheduling for the URLLC UE must be performed with the PDCCH. The scheduling must be done with the PDCCH to be transmitted in the first transmission slot. The gNB shall include in the DCI of the PDCCH scheduling information for the URLLC UE to multiplex with the PDCCH for the eMBB UE to notify of the DCI. Upon receiving the DCI on the PDCCH, the URLLC UE may receive data to be multiplexed with the eMBB UE.

[1188] The scheduling information includes resource allocation information in which data is displayed for the URLLC UE. The resource allocation information may be resource allocation information along the frequency-time axes. The resource allocation information includes PRB information. The frequency axis resource allocation information may be used in combination with the time axis resource allocation information. The frequency axis resource allocation information includes a REG number, a RE number, and a subcarrier number. The time axis resource allocation information includes symbol information.

[1189] In a slot in which the URLLC data of the UE is multiplexed with the PDCCH for the eMBB UE, for example, the same resources as those for the slot for the first transmission cannot always be reserved. Thus, data must be mapped to a slot in which multiplexing is performed by changing the modulation method or coding rate. These pieces of information should be included as scheduling information. Information may be provided indicating how many times upon retransmission these pieces of scheduling information are applied. The gNB may associate the scheduling information in the multiplex with information indicating how many times, upon retransmission, to notify the URLLC UE of these pieces of information.

[1190] FIG. 65 illustrates a method for multiplexing a PDCCH for an eMBB UE with a slot for a URLLC UE. Fig. 65 illustrates data retransmission for URLLC UE over slots for eMBB UE. The number of data retransmissions for a URLLC UE is assumed to be two. Resources for the eMBB UE are preempted for the first URLLC data link UE in slot #1 with respect to the eMBB UE.

[1191] The gNB transmits the second data in the next slot to the URLLC UE. When the second data slot of the URLLC UE is used as the resources on which the PDCCH for the eMBB UE is mapped, the second data for the URLLC UE is mapped to resources other than CORESET for the eMBB UE, as illustrated in FIG. 65.

[1192] The gNB includes in the PDCCH for the URLLC UE to be transmitted in the slot for the first data of the URLLC UE, scheduling information for the second data for the URLLC UE to notify the URLLC UE of the PDCCH. Therefore, the PDCCH for the eMBB UE may be multiplexed with the data for the URLLC UE in symbols in which the PDCCH in slot #2 for the eMBB UE may be mapped. The repeated data for the URLLC UE is transmitted in slot #2 for the eMBB UE.

[1193] When retransmission of data for the URLLC UE is configured for increased reliability, even in the presence of a symbol in which the PDCCH for the eMBB UE is transmitted with a time reference to perform the retransmission, the data for the URLLC UE can be transmitted in a symbol without failing to transmit the PDCCH for eMBB UE.

[1194] Ensuring early transmission to the URLLC UE can result in high reliability and low latency performance. Since the PDCCH for the eMBB UE can also be transmitted, communication for data transmission at the eMBB UE is possible. Thus, high-speed, high-capacity communication is possible.

[1195] Sixth modification of the seventh embodiment

In the DL, the resources on which the PDSCH for the eMBB UE is mapped may be temporally partitioned by preemption. After a portion of the resources for the PDSCH is transmitted, the resources for the eMBB UE may be preempted and thus not transmitted, and then the remaining PDSCH may be transmitted.

[1196] In such a case, there may be no phase or power continuity of the PDSCH in transmission before and after the resources to preempt. Even though DMRS is configured before or after resources for preemption, discontinuity in phase or power degrades demodulation performance in PDSCH with resources in which DMRS is not configured.

[1197] A method for configuring an incremental DMRS should be applied to a method for solving such a problem. The incremental DMRS must be configured so that the DMRS are configured both before and after the preemption resources. This can, for example, reduce degradation in demodulation performance when preemption causes discontinuity in phase or power before and after resources.

[1198] FIG. 66 illustrates an example of resource preemption for PDSCH when only FL-DMRS is configured in one slot for an eMBB UE. The gNB transmits FL-DMRS and PDSCH to the eMBB UE prior to pre-pushing, transmits nothing to the eMBB UE with the resources to preempt, and transmits the PDSCH to the eMBB UE after pre-push.

[1199] Thus, there is no phase or power continuity of the PDSCH before and after the preemption. The eMBB UE may receive FL-DMRS and demodulate the PDSCH prior to pre-population with FL-DMRS. However, when the eMBB UE demodulates the PDSCH after being preempted by FL-DMRS, discontinuity in phase or power degrades the demodulation performance.

[1200] To mitigate such problems, gNB configures DMRS after resources to preempt. A method must be applied to configure an additional DMRS as a DMRS. The method disclosed in the seventh embodiment should be properly applied.

[1201] The gNB configures the supplemental DMRS for the eMBB UE in the PDSCH region after preemption, and transmits the supplemental DMRS. The eMBB UE receives the supplemental DMRS configured in the PDSCH after the preemption and demodulates the PDSCH. This can reduce the demodulation degradation of the PDSCH after the preemption in the eMBB UE.

[1202] In UL, the resources on which the PUSCH for the eMBB UE is mapped may be time-staggered by preemption. After a portion of the resources for the PUSCH is transmitted, the resources for the eMBB UE may be preempted and thus not transmitted, and then the remaining PUSCH may be transmitted.

[1203] In such a case, there may be no phase or power continuity of the PUSCH when transmitting before and after resources to preempt. Even though DMRS is configured before or after resources for preemption, discontinuity in phase or power degrades demodulation performance in PUSCH with resources in which DMRS is not configured.

[1204] A method for configuring an incremental DMRS should be applied to a method for solving such a problem. The incremental DMRS must be configured so that the DMRS are configured both before and after the preemption resources. This can, for example, reduce degradation in demodulation performance when preemption causes discontinuity in phase or power before and after resources.

[1205] FIG. 67 illustrates an example of resource preemption for PUSCH when only FL-DMRS is configured in one slot for the eMBB UE. The eMBB UE transmits FL-DMRS and PUSCH before padding, transmits nothing with padding resources, and transmits PUSCH after padding.

[1206] Thus, there is no phase or power continuity in the PUSCH before and after the preemption. The gNB may receive FL-DMRS and demodulate the PUSCH prior to pre-population with FL-DMRS. However, when the gNB demodulates the PUSCH after being preempted by FL-DMRS, discontinuity in phase or power degrades the demodulation performance.

[1207] To reduce such problems, gNB configures DMRS after resources to preempt. A method must be applied to configure an additional DMRS as a DMRS. The method disclosed in the seventh embodiment should be properly applied.

[1208] The gNB configures the supplemental DMRS for transmission from the eMBB UE in the PUSCH region after preemption. The eMBB UE transmits the configured supplemental DMRS. The gNB receives the incremental DMRS after the preemption, and demodulates the PUSCH after the preemption. This can reduce the demodulation degradation of the PUSCH after being preempted in the gNB.

[1209] A plurality of supplemental DMRSs may be configured in both DL and UL. To do this, a method for configuring an additional DMRS can be applied.

[1210] FIG. 68 illustrates an example of configuring a plurality of supplemental DMRSs in a UL. Fig. 68 illustrates an example of DMRS preemption when only DMRS is configured in one slot of the eMBB UE. PUSCH are configured before and after DMRS. The two additional DMRSs are configured before and after the resources to preempt.

[1211] DMRS preemption makes the gNB unable to demodulate the PUSCH from the eMBB UE. To solve such a problem, incremental DMRS can only be configured before and after DMRS. However, discontinuity in the phase or power of the PUSCH before and after preemption degrades the demodulation performance of a PUSCH for which supplemental DMRS is not configured.

[1212] To reduce such problems, gNB configures DMRS before and after resources to preempt. A method must be applied to configure an additional DMRS as a DMRS. The method disclosed in the second modification of the seventh embodiment should be properly applied.

[1213] The gNB configures an incremental DMRS in the PUSCH region before preemption, and configures an incremental DMRS in the PUSCH region after preemption. The eMBB UE transmits two configured supplemental DMRS. The gNB receives the incremental DMRS prior to pre-preemption and demodulates the PUSCH prior to pre-preemption. The gNB also receives the incremental DMRS after the preemption and demodulates the PUSCH after the preemption.

[1214] This can reduce degradation in the PUSCH demodulation performance before and after the gNBs are preempted.

[1215] Although the resources to be preempted are for Enhanced Mobile Broadband (eMBB), which is classified as high-speed, high-capacity communications, and the preemptive resources are for Ultra Reliable Low Latency Communication (URLLC), which is classified as ultra-reliable low latency communication, the application is not limited to these services. Communication services to be used for resources to be preempted and communication services to be used for preemptive resources are not limited to eMBB and URLLC.

[1216] Although the UE to be preempted (preempted UE) is a UE for an eMBB service (eMBB UE) and the preemptive UE is a UE for a URLLC service (URLLC UE), the preempted UE and the preempted UE are not limited to the UE for these services.

[1217] Eighth Embodiment

Configuring an uplink preemptive transmission of a communication service requiring low latency may result in low latency performance. However, simply configuring preemptive transmission may not be able to fulfill the requirements of a communication service that requires not only low latency characteristics but also high reliability characteristics such as URLLC services.

[1218] The solution to the problem is disclosed below.

[1219] Preemptive transmission can be configured in packet duplication, in which a packet is duplicated and identical packets are transmitted by the DC. Preemptive transmission can be configured in the MN during packet duplication setup. Preemptive transmission can also be configured in the SN during packet duplication setup. Alternatively, a preemptive transmission may be configured in one of the MNs and SNs during packet duplication setup. "During installation of duplicate layouts" may include the time during which the installation of duplicate packages is processed.

[1220] Packet duplication may be configurable in uplink communication in which preemptive transmission has been configured. When packet duplication is performed in an uplink communication in which preemptive transmission has been configured, preemptive transmission may also be configured in the SN. As such, configuring both packet duplication and preemptive transmission can improve not only low latency performance but also reliability.

[1221] When duplicating packets with a DC, packet duplication is configured between the MN and the UE. Thus, the SN does not need to recognize the duplicate packet configuration. The SN only needs to perform processes identical to the normal processes for transmitting and receiving packet data. As described earlier, an RRC configuration is necessary to configure a preemptive transmission. Thus, when an attempt is made to configure a preemptive transmission with duplication of packets using a DC, the SN cannot recognize whether it is necessary to configure the preemptive transmission. Thus, the SN has a problem that it is unable to configure preemptive transmission.

[1222] The method disclosed in the second embodiment is to be applied as a solution to the problem. An unlicensed transfer should be used as a substitute for a preemptive transfer. For example, the MN requests the MN to configure a preemptive transmission. The MN requests the SN to configure the preemption transmission during the duplication of packets setup. The SN notifies the MN of the configuration for preemptive transmission. The MN notifies the UE of the pop-up configuration that has been configured in its own node and the SN's configuration of the pop-up transmission.

[1223] This can create the same benefits as disclosed in the second embodiment. For example, the SN may recognize whether it is necessary to configure the preemptive transmission and configure the preemptive transmission. In this way, the SN can configure preemptive transmission when duplicating packets with the DC. This results in low latency performance and high reliability performance.

[1224] The same is true when the MN attempts to configure duplication of packets in an uplink communication in which preemptive transmission has been configured. The method disclosed in the second embodiment should be applied.

[1225] For example, the MN notifies the UE of configuring the duplication of packets with the DC in the uplink communication in which the preemptive transmission has been configured. In addition, the MN requests the SN to configure the preemptive transmission. The MN may notify the SN of the instruction to configure the preemptive transmission. The SN notifies the MN of the configuration for preemptive transmission. The MN notifies the UE of the pop-up configuration that is configured in its own node and the SN's pop-up configuration.

[1226] This can create the same benefits as disclosed in the second embodiment. For example, the SN may recognize whether it is necessary to configure the preemptive transmission and configure the preemptive transmission. Thus, the MN can configure the duplication of packets in the uplink communication in which the preemptive transmission has been configured. This results in low latency performance and high reliability performance.

[1227] Preemption transmission can be configurable in packet duplication, in which a packet is duplicated and identical packets are transmitted by a CA. Preemptive transmission may be configured in the cell in which packet duplication is to be performed at the time of packet duplication setup. "During installation of duplicate packages" may include the time during which the installation of duplicate packages is processed.

[1228] Packet duplication (CA) may be configurable in uplink communication in which preemptive transmission has been configured. When packet duplication is performed in the uplink communication in which preemptive transmission has been configured, preemption transmission may also be configured in the cell in which packet duplication is to be performed.

[1229] The methods disclosed in the second embodiment should be applied to these methods. An unlicensed transfer should be used as a substitute for a preemptive transfer. This can create the same benefits.

[1230] Embodiments and modifications are merely illustrative of the present invention and may be freely combined within the scope of the present invention. Any constituent elements of the embodiments and modifications may be appropriately modified or omitted.

[1231] A subframe in embodiments and modifications is an exemplary unit of communication time in a fifth generation base station communication system. The subframe may be configured by scheduling. The processes described in the embodiments and modifications as being performed per subframe may be performed per TTI, per slot, per sub-slot, or per mini-slot.

[1232] While the invention has been described in detail, the foregoing description is in all respects illustrative and does not limit the present invention. As a consequence, numerous modifications and variations that have not yet been illustrated have been developed without departing from the scope of the present invention.

Description of Symbols

[1233] 200 is a communication system, 202 is a communication terminal device, 203 is a base station device.

Claims (34)

1. A communication system, comprising: user device; And base stations, respectively, configured to communicate wirelessly with the user device, wherein the base stations include a main base station and a secondary base station that configure dual connectivity for the user equipment, and the secondary base station is configured with a grant configuration related to non-grant transmission in the uplink to the secondary base station. 2. The communication system of claim 1, wherein the grant-configuration-based transmission is an uplink transmission not requiring a grant granted from the secondary base station at the request of the user equipment. 3. Communication system according to claim 1, in which the secondary base station notifies the master base station of the grant configuration, and the host base station notifies the user device of the reported permission configuration. 4. The communication system according to claim 1, wherein the main base station notifies the user equipment of the L1 configuration specifying a customizable permission configuration parameter. 5. The communication system of claim 1, wherein the secondary base station notifies the user equipment of part or all of the RRC configuration corresponding to the grant configuration. 6. Communication system according to claim 1, in which the secondary base station notifies the main base station of information indicating a change in the grant configuration, and the master base station notifies the user equipment of the information reported from the secondary base station. 7. Communication system according to claim 1, in which the secondary base station notifies the main base station of information indicating the cancellation of the transmission without permission based on the permission configuration, and the master base station notifies the user equipment of the information reported from the secondary base station. 8. The communication system of claim 1, wherein the main base station is configured, regardless of said grant configuration for the secondary base station, with a grant configuration related to uplink non-grant transmission to the main base station. 9. The communication system according to claim 8, wherein, when duplicating packets, the main base station is configured with permission. 10. The communication system of claim 1, wherein the user equipment measures a quality of service (QoS) value and latency of the uplink packet data. 11. The communication system of claim 1, wherein the secondary base station applies the grant configuration to the SCG radio bearer or split radio bearer corresponding to the secondary base station. 12. The communication system of claim 1, wherein, in carrier aggregation, at least one of said base stations is configured with a permission configuration. 13. The communication system of claim 12, wherein, in the carrier aggregation in which the resolution configuration is configured, duplication of packets is further configured. 14. The communication system of claim 1, wherein the secondary base station is configured with a permission configuration for each of one or more cells formed by the secondary base station. 15. The communication system of claim 1, wherein the main base station is configured with a permission configuration for each of one or more cells formed by the main base station. 16. The communication system according to claim 1, wherein, when duplicating packets, the secondary base station is configured with permission. 17. The communication system of claim 1, wherein the user equipment performs uplink transmission on a wireless resource configured to transmit without permission according to a priority based on information reported by RRC signaling. 18. The communication system of claim 17, wherein the priority followed by the user equipment is a priority according to a channel. 19. A user device in a communication system containing this user device and base stations, respectively, configured to communicate wirelessly with the user device, while the base stations include a main base station and a secondary base station that configure dual connectivity for the user equipment, and the user equipment performs uplink transmission based on the grant configuration related to the uplink non-grant transmission to the secondary base station. 20. A base station in a communication system comprising a user device and base stations, respectively, configured to communicate wirelessly with the user device, wherein the base stations include a main base station and a secondary base station that configure dual connectivity for the user equipment, and the secondary base station is configured with a grant configuration related to non-grant transmission in the uplink to the secondary base station.

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