KR20210155762A - Method and apparatus for extending coverage in communication system - Google Patents

Abstract

Disclosed are a method and device for extending a coverage in a communication system. An operation method of a terminal includes the steps of: receiving a first RA configuration information and a second RA configuration information from a base station; transmitting Msg1 to a base station based on the second RA configuration information; receiving Msg2, which is a response to the Msg1, from the base station; and repeatedly transmitting Msg3 K times to the base station. Therefore, an RA procedure between the base station and the terminal can be efficiently performed.

Description

METHOD AND APPARATUS FOR EXTENDING COVERAGE IN COMMUNICATION SYSTEM

The present invention relates to a coverage extension technology in a communication system, and more particularly, to a technology for coverage extension of an uplink signal and/or a channel.

For processing of rapidly increasing wireless data, a frequency band (eg, 6 GHz) higher than a frequency band (eg, a frequency band of 6 GHz or less) of a long term evolution (LTE) communication system (or LTE-A communication system) A communication system (eg, a new radio (NR) communication system) using the above frequency bands) is being considered. The NR system may support a frequency band of 6 GHz or less as well as a frequency band of 6 GHz or higher, and may support various communication services and scenarios compared to the LTE system. In addition, the requirements of the NR system may include enhanced Mobile BroadBand (eMBB), Ultra Reliable Low Latency Communication (URLLC), massive Machine Type Communication (mMTC), and the like.

Meanwhile, in order to reduce an error rate of data, a lower modulation and coding scheme (MCS) may be used. In order to prevent the size of a field indicating MCS in downlink control information (DCI) from becoming too large, frequently used MCSs may be selectively used. If it is necessary to apply a lower MCS, repeated transmission may be used. If Quadrature Phase Shift Keying (QPSK), which is the lowest modulation rate in repeated transmission, is used, the effect of further lowering the code rate may be obtained. In particular, in the case of uplink, since transmission power is limited, repeated transmission in the time domain may be utilized rather than repetitive transmission in the frequency domain.

A low MCS may be used for eMBB traffic and URLLC traffic supported by a 5G system (eg, an NR system). The purpose of using the low MCS for eMBB traffic may be different from the purpose of using the low MCS for URLLC traffic. For example, to extend the reach of eMBB traffic, a lower MCS may be needed. In order to obtain a lower error rate and reduced latency of URLLC traffic, a lower MCS may be required. Since the requirements of eMBB traffic are different from those of URLLC traffic, eMBB traffic may be repeatedly transmitted despite a relatively long delay time. On the other hand, in the case of URLLC traffic, new MCS(s) may be introduced rather than repeated transmission, and the new MCS(s) may be indicated by radio resource control (RRC) signaling and/or DCI signaling.

In order to support repetitive transmission of eMBB traffic in the time domain, a physical uplink shared channel (PUSCH) repetition (eg, PUSCH repetition type A) may be introduced. When PUSCH repetition is used, the PUSCH allocated in units of slots (eg, PUSCH mapping type A) may be repeatedly transmitted. In order to extend the reach of the PUSCH, a time resource including a plurality of slots may be allocated. When DCI signaling (eg, type 2 CG (configured grant), dynamic grant) and/or RRC signaling (eg, type 1 CG) is used, time resource allocation is transmitted in the first slot It may include only time resources for In this case, the time resource of PUSCH repetition type A may be determined by indicating the number of repetitions (eg, the number of repeated transmissions) through RRC signaling.

When repeated transmission of URLLC traffic is performed, it may not be appropriate to repeatedly transmit URLLC traffic because a delay time occurs. However, when a low MCS is used for transmission of URLLC traffic, the delay for decoding may be reduced. When a low MCS is used, the number of resource elements (REs) for transmission of URLLC traffic may increase, and accordingly, a base station (eg, a decoder of a base station) may wait until all REs are received. Accordingly, the delay for decoding the URLLC traffic can be reduced.

When the PUSCH is repeatedly transmitted using a high MCS, the base station may perform a decoding operation with only some REs. The first successful decoding time may be faster than a case in which a lower MCS is applied in single transmission. Since unnecessary delay time occurs when PUSCH repetition type A is used, PUSCH repetition type B may be introduced to reduce the delay time for repetitive transmission. When PUSCH repetition type B is used, PUSCH (eg, PUSCH mapping type B) allocated in mini-slot units may be repeatedly transmitted. When DCI signaling (eg, type 2 CG, dynamic grant) and/or RRC signaling (eg, type 1 CG) is used, the combination of the reference time resource and the number of repetitions of one PUSCH instance is can be directed. The time resource of PUSCH repetition type B may be determined based on the above-described combination. A technique for extending the coverage area of the aforementioned signal and/or channel (eg, PUSCH) may be required.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems to provide a method and apparatus for extending the coverage area of a signal and/or a channel in a communication system.

In order to achieve the above object, a method of operating a terminal according to a first embodiment of the present invention includes receiving first RA configuration information and second RA configuration information from a base station, and selecting Msg1 based on the second RA configuration information. transmitting to the base station, receiving Msg2, which is a response to the Msg1, from the base station, and repeatedly transmitting Msg3 to the base station K times, wherein the first RA configuration information satisfies a first condition The Msg3 is not repeatedly transmitted in the first RA procedure according to the first RA configuration information, and the second RA configuration information is used when the first condition is not satisfied, and the second RA configuration information is used when the first condition is not satisfied. In the second RA procedure according to information, Msg3 is repeatedly transmitted, and K is a natural number.

The method of operating the terminal may further include, before transmission of the Msg1, transmitting information indicating whether the terminal supports repeated transmission of the Msg3 to the base station.

The first RA preamble indicated by the first RA configuration information may be distinguished from the second RA preamble indicated by the second RA configuration information, and the Msg1 may be generated based on the second RA preamble. .

The first PRACH occasion indicated by the first RA configuration information may be the same as the second PRACH occasion indicated by the second RA configuration information, and the Msg1 according to the second RA configuration information is a PRACH mask. can be distinguished from Msg1 according to the first RA configuration information.

The first condition may be a case in which the measurement result of the signal received from the base station exceeds a threshold value, and the threshold value is to be included in at least one of system information, the first RA configuration information, and the second RA configuration information. can

The second RA configuration information may include information indicating the K.

The number of SLIVs included in the TDRA table referenced by the UL grant included in Msg2 may indicate K.

The K may be indicated from an index included in the TDRA table referenced by the UL grant included in Msg2.

The UL grant included in Msg2 may include information indicating a TDRA table used for repeated transmission of Msg3, and the TDRA table may include information indicating the K.

The K may be determined based on the number of valid slots in which repeated transmission of the Msg3 is possible.

The method of operating the terminal may further include receiving a DCI including information indicating the K from the base station, and the Msg3 may be repeatedly transmitted according to the K indicated by the DCI.

In order to achieve the above object, a method of operating a base station according to a second embodiment of the present invention includes generating first RA configuration information used when a first condition is satisfied, and when the first condition is not satisfied generating second RA configuration information used for , transmitting Msg2, which is a response to the Msg1, to the terminal, and repeatedly receiving Msg3 from the terminal K times, wherein in a first RA procedure according to the first RA configuration information, the Msg3 is repeatedly transmitted In the second RA procedure according to the second RA configuration information, the Msg3 is repeatedly transmitted, and K is a natural number.

The method of operating the base station may further include, before receiving the Msg1, receiving information indicating whether the terminal supports repeated transmission of the Msg3 from the terminal.

The first RA preamble indicated by the first RA configuration information may be distinguished from the second RA preamble indicated by the second RA configuration information, and the Msg1 may be generated based on the second RA preamble. .

The first PRACH occasion indicated by the first RA configuration information may be the same as the second PRACH occasion indicated by the second RA configuration information, and the Msg1 according to the second RA configuration information is a PRACH mask. can be distinguished from Msg1 according to the first RA configuration information.

The first condition may be a case in which the measurement result of the signal received from the base station exceeds a threshold value, and the threshold value is to be included in at least one of system information, the first RA configuration information, and the second RA configuration information. can

The second RA configuration information may include information indicating the K.

The number of SLIVs included in the TDRA table referenced by the UL grant included in Msg2 or an index included in the TDRA table may indicate K.

The UL grant included in Msg2 may include information indicating a TDRA table used for repeated transmission of Msg3, and the TDRA table may include information indicating the K.

The K may be determined based on the number of valid slots in which repeated transmission of the Msg3 is possible.

According to the present invention, the base station may inform the terminal of the number of repetitions of Msg3 for a random access (RA) procedure. The terminal may check the number of repetitions of Msg3 based on the information received from the base station, and may repeatedly transmit Msg3. When Msg3 is repeatedly transmitted, the reach area of Msg3 may increase. Accordingly, the RA procedure between the base station and the terminal can be efficiently performed, and the performance of the communication system can be improved.

1 is a conceptual diagram illustrating a first embodiment of a communication system.
2 is a block diagram showing a first embodiment of a communication node constituting a communication system.
3 is a conceptual diagram illustrating a first embodiment to which PUSCH repetition type A is applied.
4 is a conceptual diagram illustrating a first embodiment of a method of applying OCC in units of actual PUSCH instances.
5 is a conceptual diagram illustrating a first embodiment of a method of applying OCC in units of slots.
6 is a conceptual diagram illustrating a first embodiment of a PUSCH transmission method according to PUSCH repetition type C. Referring to FIG.
7 is a conceptual diagram illustrating a first embodiment of a PUSCH transmission method according to PUSCH repetition type D. Referring to FIG.
8 is a conceptual diagram illustrating a second embodiment of a PUSCH transmission method according to PUSCH repetition type D. Referring to FIG.
9A is a conceptual diagram illustrating a first embodiment of a method for analyzing a time window when PUSCH repetition type B is used.
9B is a conceptual diagram illustrating a first embodiment of a method for analyzing a time window when a PUSCH repetition type BB is used.
10 is a conceptual diagram illustrating a first embodiment of a method for a terminal to transmit two or more UL occasions.
11 is a conceptual diagram illustrating a first embodiment in which a coherence window is applied based on UL occasion 1 in a transmission procedure of two or more UL occasions.
12 is a conceptual diagram illustrating a second embodiment in which a coherence window is applied based on UL occasion 1 in a transmission procedure of two or more UL occasions.
13 is a conceptual diagram illustrating a third embodiment in which a coherence window is applied based on UL occasion 1 in a transmission procedure of two or more UL occasions.
14A is a conceptual diagram illustrating a first embodiment of a method for applying frequency hopping of a PUSCH occasion.
14B is a conceptual diagram illustrating a second embodiment of a method of applying frequency hopping of a PUSCH occasion.
15A is a conceptual diagram illustrating a first embodiment of a method of applying frequency hopping to a PUSCH occasion in consideration of invalid symbols in a PUSCH occasion from which a PUSCH instance is dropped.
15B is a conceptual diagram illustrating a second embodiment of a method of applying frequency hopping to a PUSCH occasion in consideration of invalid symbols in a PUSCH occasion from which a PUSCH instance is dropped.
16A is a conceptual diagram illustrating a first embodiment of a method of applying frequency hopping to a PUSCH occasion in consideration of invalid symbols in a PUSCH occasion in which a PUSCH instance is postponed.
16B is a conceptual diagram illustrating a second embodiment of a method of applying frequency hopping to a PUSCH occasion in consideration of invalid symbols in a PUSCH occasion in which a PUSCH instance is postponed.
16C is a conceptual diagram illustrating a third embodiment of a method of applying frequency hopping to a PUSCH occasion in consideration of invalid symbols in a PUSCH occasion in which a PUSCH instance is postponed.
17 is a conceptual diagram illustrating a third embodiment of a method of applying frequency hopping to a PUSCH occasion in consideration of invalid symbols in a PUSCH occasion from which a PUSCH instance is dropped.
18A is a conceptual diagram illustrating a fourth embodiment of a method of applying frequency hopping to a PUSCH occasion in consideration of invalid symbols in a PUSCH occasion in which a PUSCH instance is postponed.
18B is a conceptual diagram illustrating a fifth embodiment of a method of applying frequency hopping to a PUSCH occasion in consideration of invalid symbols in a PUSCH occasion in which a PUSCH instance is postponed.
18C is a conceptual diagram illustrating a sixth embodiment of a method of applying frequency hopping to a PUSCH occasion in consideration of invalid symbols in a PUSCH occasion in which a PUSCH instance is postponed.
19A is a conceptual diagram illustrating a first embodiment of an IFDMA mapping method for a sub-PRB-based PUSCH.
19B is a conceptual diagram illustrating a second embodiment of an IFDMA mapping method for a sub-PRB-based PUSCH.
20A is a conceptual diagram illustrating a first embodiment of a hybrid method of IFDMA mapping and localized mapping for sub-PRB-based PUSCH.
20B is a conceptual diagram illustrating a second embodiment of a hybrid method of IFDMA mapping and localized mapping for sub-PRB-based PUSCH.
20C is a conceptual diagram illustrating a third embodiment of a hybrid method of IFDMA mapping and localized mapping for sub-PRB-based PUSCH.
21A is a conceptual diagram illustrating a first embodiment of a localized mapping method for a sub-PRB-based PUSCH.
21B is a conceptual diagram illustrating a second embodiment of a localized mapping method for a sub-PRB-based PUSCH.
22 is a conceptual diagram illustrating a first embodiment of a frequency-first RE mapping method.
23A is a conceptual diagram illustrating a first embodiment of a symbol mapping method for SFI.
23B is a conceptual diagram illustrating a second embodiment of a symbol mapping method for SFI.
24A is a conceptual diagram illustrating a first embodiment of a RE mapping method for SFI when PUCCH is repeatedly transmitted.
24B is a conceptual diagram illustrating a second embodiment of a RE mapping method for SFI when PUCCH is repeatedly transmitted.
24C is a conceptual diagram illustrating a third embodiment of a RE mapping method related to SFI when PUCCH is repeatedly transmitted.
25A is a conceptual diagram illustrating a first embodiment of a method for frequency hopping of a PUCCH occasion.
25B is a conceptual diagram illustrating a second embodiment of a method for frequency hopping of a PUCCH occasion.
26A is a conceptual diagram illustrating a first embodiment of a frequency hopping method of a PUCCH occasion considering an invalid symbol in a PUCCH occasion in which a PUCCH instance is postponed.
26B is a conceptual diagram illustrating a second embodiment of a method of frequency hopping of a PUCCH occasion in consideration of an invalid symbol in a PUCCH occasion in which a PUCCH instance is postponed.
26C is a conceptual diagram illustrating a third embodiment of a frequency hopping method of a PUCCH occasion considering an invalid symbol in a PUCCH occasion in which a PUCCH instance is postponed.
27A is a conceptual diagram illustrating a fourth embodiment of a frequency hopping method of a PUCCH occasion considering an invalid symbol in a PUCCH occasion in which a PUCCH instance is postponed.
27B is a conceptual diagram illustrating a fifth embodiment of a frequency hopping method of a PUCCH occasion considering an invalid symbol in a PUCCH occasion in which a PUCCH instance is postponed.
27C is a conceptual diagram illustrating a sixth embodiment of a frequency hopping method of a PUCCH occasion considering an invalid symbol in a PUCCH occasion in which a PUCCH instance is postponed.
28 is a conceptual diagram illustrating a first embodiment of a MAC RAR or a fallback RAR.

Since the present invention can have various changes and can have various embodiments, specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the present invention to specific embodiments, and it should be understood to include all modifications, equivalents and substitutes included in the spirit and scope of the present invention.

Terms such as first, second, etc. may be used to describe various elements, but the elements should not be limited by the terms. The above terms are used only for the purpose of distinguishing one component from another. For example, without departing from the scope of the present invention, a first component may be referred to as a second component, and similarly, a second component may also be referred to as a first component. and/or includes a combination of a plurality of related listed items or any of a plurality of related listed items.

When an element is referred to as being “connected” or “connected” to another element, it is understood that it may be directly connected or connected to the other element, but other elements may exist in between. it should be On the other hand, when it is said that a certain element is "directly connected" or "directly connected" to another element, it should be understood that the other element does not exist in the middle.

The terms used in the present application are only used to describe specific embodiments, and are not intended to limit the present invention. The singular expression includes the plural expression unless the context clearly dictates otherwise. In the present application, terms such as “comprise” or “have” are intended to designate that a feature, number, step, operation, component, part, or combination thereof described in the specification exists, but one or more other features It should be understood that this does not preclude the existence or addition of numbers, steps, operations, components, parts, or combinations thereof.

Unless defined otherwise, all terms used herein, including technical and scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Terms such as those defined in a commonly used dictionary should be interpreted as having a meaning consistent with the meaning in the context of the related art, and should not be interpreted in an ideal or excessively formal meaning unless explicitly defined in the present application. does not

Hereinafter, preferred embodiments of the present invention will be described in more detail with reference to the accompanying drawings. In describing the present invention, in order to facilitate the overall understanding, the same reference numerals are used for the same components in the drawings, and duplicate descriptions of the same components are omitted.

A communication system to which embodiments according to the present invention are applied will be described. The communication system to which the embodiments according to the present invention are applied is not limited to the content described below, and the embodiments according to the present invention can be applied to various communication systems. Here, a communication system may be used in the same sense as a communication network (network).

1 is a conceptual diagram illustrating a first embodiment of a communication system.

1, the communication system 100 is a plurality of communication nodes (110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-4, 130-5, 130-6). In addition, the communication system 100 is a core network (core network) (eg, S-GW (serving-gateway), P-GW (packet data network (PDN)-gateway), MME (mobility management entity)) may include more. When the communication system 100 is a 5G communication system (eg, a new radio (NR) system), the core network is an access and mobility management function (AMF), a user plane function (UPF), a session management function (SMF), etc. may include

The plurality of communication nodes 110 to 130 may support a communication protocol (eg, an LTE communication protocol, an LTE-A communication protocol, an NR communication protocol, etc.) defined in a 3rd generation partnership project (3GPP) standard. A plurality of communication nodes 110 to 130 are CDMA (code division multiple access) technology, WCDMA (wideband CDMA) technology, TDMA (time division multiple access) technology, FDMA (frequency division multiple access) technology, OFDM (orthogonal frequency division) technology multiplexing) technology, Filtered OFDM technology, CP (cyclic prefix)-OFDM technology, DFT-s-OFDM (discrete Fourier transform-spread-OFDM) technology, OFDMA (orthogonal frequency division multiple access) technology, SC (single carrier)-FDMA Technology, Non-orthogonal Multiple Access (NOMA) technology, GFDM (generalized frequency division multiplexing) technology, FBMC (filter bank multi-carrier) technology, UFMC (universal filtered multi-carrier) technology, SDMA (Space Division Multiple Access) technology, etc. can support Each of the plurality of communication nodes may have the following structure.

2 is a block diagram showing a first embodiment of a communication node constituting a communication system.

Referring to FIG. 2 , the communication node 200 may include at least one processor 210 , a memory 220 , and a transceiver 230 connected to a network to perform communication. In addition, the communication node 200 may further include an input interface device 240 , an output interface device 250 , a storage device 260 , and the like. Each of the components included in the communication node 200 may be connected by a bus 270 to communicate with each other.

However, each of the components included in the communication node 200 may not be connected to the common bus 270 but to the processor 210 through an individual interface or an individual bus. For example, the processor 210 may be connected to at least one of the memory 220 , the transceiver 230 , the input interface device 240 , the output interface device 250 , and the storage device 260 through a dedicated interface. .

The processor 210 may execute a program command stored in at least one of the memory 220 and the storage device 260 . The processor 210 may mean a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to embodiments of the present invention are performed. Each of the memory 220 and the storage device 260 may be configured as at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory 220 may be configured as at least one of a read only memory (ROM) and a random access memory (RAM).

Referring back to FIG. 1 , the communication system 100 includes a plurality of base stations 110 - 1 , 110 - 2 , 110 - 3 , 120 - 1 and 120 - 2 , and a plurality of terminals 130 - 1, 130-2, 130-3, 130-4, 130-5, 130-6). Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 may form a macro cell. Each of the fourth base station 120-1 and the fifth base station 120-2 may form a small cell. The fourth base station 120-1, the third terminal 130-3, and the fourth terminal 130-4 may belong to the cell coverage of the first base station 110-1. The second terminal 130-2, the fourth terminal 130-4, and the fifth terminal 130-5 may belong to the cell coverage of the second base station 110-2. The fifth base station 120-2, the fourth terminal 130-4, the fifth terminal 130-5, and the sixth terminal 130-6 may belong to the cell coverage of the third base station 110-3. have. The first terminal 130-1 may belong to the cell coverage of the fourth base station 120-1. The sixth terminal 130-6 may belong to the cell coverage of the fifth base station 120-2.

Here, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 is a NodeB (NB), an evolved NodeB (eNB), gNB, an advanced base station (ABS), HR - BS (high reliability-base station), BTS (base transceiver station), radio base station (radio base station), radio transceiver (radio transceiver), access point (access point), access node (node), RAS (radio access station) ), MMR-BS (mobile multihop relay-base station), RS (relay station), ARS (advanced relay station), HR-RS (high reliability-relay station), HNB (home NodeB), HeNB (home eNodeB), It may be referred to as a road side unit (RSU), a radio remote head (RRH), a transmission point (TP), a transmission and reception point (TRP), and the like.

Each of the plurality of terminals 130-1, 130-2, 130-3, 130-4, 130-5, 130-6 includes a user equipment (UE), a terminal equipment (TE), an advanced mobile station (AMS), HR-MS (high reliability-mobile station), terminal, access terminal, mobile terminal, station, subscriber station, mobile station, portable It may be referred to as a portable subscriber station, a node, a device, an on board unit (OBU), and the like.

Meanwhile, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may operate in different frequency bands or may operate in the same frequency band. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be connected to each other through an ideal backhaul link or a non-ideal backhaul link. , information can be exchanged with each other through an ideal backhaul link or a non-ideal backhaul link. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be connected to the core network through an ideal backhaul link or a non-ideal backhaul link. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 transmits a signal received from the core network to the corresponding terminals 130-1, 130-2, 130-3, 130 -4, 130-5, 130-6), and a signal received from the corresponding terminal (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) is transmitted to the core network can be sent to

In addition, each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 transmits MIMO (eg, single user (SU)-MIMO, multi user (MU)- MIMO, massive MIMO, etc.), coordinated multipoint (CoMP) transmission, carrier aggregation (CA) transmission, transmission in an unlicensed band, direct communication between terminals (device to device communication, D2D) (or , Proximity Services (ProSe)), Internet of Things (IoT) communication, dual connectivity (DC), and the like may be supported. Here, each of the plurality of terminals 130-1, 130-2, 130-3, 130-4, 130-5, 130-6 is the base station 110-1, 110-2, 110-3, and 120-1. , 120-2) and corresponding operations, and operations supported by the base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be performed. For example, the second base station 110-2 may transmit a signal to the fourth terminal 130-4 based on the SU-MIMO method, and the fourth terminal 130-4 may transmit a signal based on the SU-MIMO method. A signal may be received from the second base station 110 - 2 . Alternatively, the second base station 110 - 2 may transmit a signal to the fourth terminal 130 - 4 and the fifth terminal 130 - 5 based on the MU-MIMO scheme, and the fourth terminal 130 - 4 . and each of the fifth terminals 130 - 5 may receive a signal from the second base station 110 - 2 by the MU-MIMO method.

Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 may transmit a signal to the fourth terminal 130-4 based on the CoMP scheme, and the fourth The terminal 130-4 may receive signals from the first base station 110-1, the second base station 110-2, and the third base station 110-3 by the CoMP method. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 is a terminal 130-1, 130-2, 130-3, 130-4 belonging to its own cell coverage. , 130-5, 130-6) and the CA method can transmit and receive signals. Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 controls D2D between the fourth terminal 130-4 and the fifth terminal 130-5. and each of the fourth terminal 130-4 and the fifth terminal 130-5 may perform D2D under the control of the second base station 110-2 and the third base station 110-3, respectively. .

Next, operating methods of a communication node in a communication system will be described. Even when a method (eg, transmission or reception of a signal) performed in a first communication node among communication nodes is described, a corresponding second communication node is a method (eg, a method corresponding to the method performed in the first communication node) For example, reception or transmission of a signal) may be performed. That is, when the operation of the terminal is described, the corresponding base station may perform the operation corresponding to the operation of the terminal. Conversely, when the operation of the base station is described, the corresponding terminal may perform the operation corresponding to the operation of the base station.

Chapter 2 How to extend the reach of a physical uplink shared channel (PUSCH)

2.1 How to improve in the spatial domain

When the arrival area of the PUSCH is not wide enough, it may be desirable to allocate resources so that the multiplexing gain for the PUSCH is improved in the base station. The multiplexing gain may be obtained by performing spatial multiplexing and/or preprocessing.

2.1.1 Transmission method based on codebook

A set of PMI (precoding metric indicator) that the base station can indicate to the terminal may be limited according to the terminal capability (UE capability). For example, the base station may instruct (eg, set) one or more of fullyAndPartialAndNonCoherent, partialAndNonCoherent, or nonCoherent to the terminal using higher layer signaling. The UE may check information indicated by higher layer signaling. When fullyAndPartialAndNonCoherent is indicated, the UE may perform coherent transmission between all antenna ports. When partialAndNonCoherent is indicated, the UE cannot perform coherent transmission between antenna port pairs, but may perform coherent transmission between antenna ports belonging to the antenna port pair. When nonCoherent is indicated, the UE cannot perform coherent transmission for each antenna port. Therefore, the base station may not allocate a specific PMI according to the terminal capability. That is, when "the maximum rank that the terminal can support", "the maximum number of antenna ports that the terminal can support", and/or "terminal capability" are indicated by RRC signaling, transmitted TPMI indicated to the terminal precoding matrix indicator) index(s) may be limited to some of the TPMI indexes defined in the technical standard.

For example, the maximum rank indicated to the terminal may be 1, and the number (eg, the maximum number) of antenna ports indicated to the terminal may be 2. In this case, communication between the terminal and the base station may be performed based on Table 1 below. The TPMI (eg, TPMI index) used by the UE may be determined based on a value of a field included in uplink-downlink control information (UL-DCI). UL-DCI may be DCI including information element(s) for uplink communication. In embodiments, TPMI may mean a TPMI index.

A value of the TPMI index may be indicated by Table 2 below. When fullyAndPartialAndNonCoherent is indicated by RRC signaling, the UE may know in advance that TPMI is selected from among TPMI 0, 1, 2, 3, 4, and 5. When noncoherent is indicated by RRC signaling, the UE may know in advance that TPMI is selected from TPMI 0 and TPMI 1.

When a PUSCH (eg, PUSCH resource) is allocated by UL-DCI, the UL-DCI may include one TPMI. That is, UL-DCI may indicate one TPMI to the UE. When PUSCH (eg, PUSCH resource) is allocated as RRC signaling (or when PUSCH is activated by DCI), RRC signaling may include one TPMI. That is, RRC signaling may indicate one TPMI to the UE.

Method 2.1-1: The TPMI indicated by the base station may be applied to the first PUSCH instance belonging to the PUSCH occasion.

When two or more PUSCH instances are configured in a PUSCH occasion, two or more TPMIs may be implicitly indicated to the UE. According to method 2.1-1, since the TPMI indicated by the base station is applied in the first PUSCH instance, the UE can derive the TPMI applied in the PUSCH instances after the first PUSCH instance.

The UE may support only specific TPMIs according to its capabilities. Therefore, the set from which the TPMI is derived may be determined according to the terminal capability. The set from which the TPMI is derived may have the same number of antenna ports and layers as the TPMI indicated to the terminal. The UE may sequentially select TPMIs from the above-described set, and may transmit a PUSCH instance using the selected TPMI.

Method 2.1-2: In a set of derived TPMIs, TPMI indexes may be sequentially applied to PUSCH instances.

For example, the maximum rank indicated to the terminal may be 1, and the number (eg, the maximum number) of antenna ports indicated to the terminal may be 2. The UE may derive the TPMI from Table 1 and/or Table 2. When fullyAndPartialAndNonCoherent is indicated by RRC signaling, the set of TPMIs may include TPMIs 0, 1, 2, 3, 4, and 5. When the TPMI index indicated to the UE is 3, TPMI 3 may be applied to the first PUSCH instance based on method 2.1-1. In PUSCH instance(s) after the first PUSCH instance, TPMI 4, 5, 0, 1, 2, etc. may be sequentially applied based on method 2.1-2. When noncoherent is indicated by RRC signaling, the set of TPMIs may include TPMIs 0 and 1. When the TPMI index indicated to the UE is 1, TPMI 1 may be applied to the first PUSCH instance based on method 2.1-1. In PUSCH instance(s) after the first PUSCH instance, TPMI 0, 1, 0, 1, etc. may be sequentially applied based on method 2.1-2.

Method 2.1-3: The TPMI index indicated by the base station may be applied to all PUSCH instances. For example, the TPMI index indicated to the UE may be equally applied to all PUSCH instances belonging to the PUSCH occasion.

Meanwhile, a method of applying TPMI may be indicated to the UE by RRC signaling. Based on one value indicated by RRC signaling, one TPMI indicated to the UE may be applied to all PUSCH instances. Based on other values indicated by RRC signaling, TPMI may be applied differently for each PUSCH instance. For example, one TPMI indicated to the UE may be applied to the first PUSCH instance, and a TPMI following a predefined order may be applied to PUSCH instance(s) after the first PUSCH instance.

2.2 DM-RS (demodulation-reference signal) improvement method

The base station may estimate the channel by using the PUSCH DM-RS to decode the PUSCH. In order to widen the coverage area of the PUSCH, it may be desirable for the base station to estimate the channel by using all DM-RSs belonging to the PUSCH. In the case of "the terminal does not have mobility" or "the terminal has little mobility", the change in the channel value experienced by the base station may not be large. According to the technical standard, when the PUSCH instances are different (or the frequency hops are different in the same PUSCH instance), the UE may not need to guarantee phase continuity. The base station may estimate a channel by using a DM-RS (eg, PUSCH DM-RS) belonging to a frequency hop unit of a PUSCH instance.

When the PUSCH occasion is transmitted in a plurality of slots, the base station may improve the quality of channel estimation by using all DM-RSs. When the interval between PUSCH instances belonging to a PUSCH occasion is a slot or a mini-slot, it may be desirable to utilize both a DM-RS belonging to a PUSCH instance or a DM-RS belonging to adjacent PUSCH instances.

Method 2.2-1 : By RRC signaling, the UE determines that the DM-RS belonging to the frequency hop(s) of the PUSCH instance(s) using the same frequency resource among one or more PUSCH instances has phase continuity or phase coherence ) to transmit the corresponding DM-RS.

The DM-RS may have power continuity (or power coherence) as well as phase continuity (or phase coherence). This is because, if the DM-RS does not have power continuity, it may be difficult to have phase continuity due to the nonlinear characteristic of the power amplifier. The non-linear characteristic may be caused by a change in the amplitude to be amplified in the power amplifier (eg, the amplitude changing by more than a preset threshold). Power continuity may mean that the amplitude amplified in the power amplifier is kept constant.

In order to maintain independent phase/power continuity per slot or nominal PUSCH instance, the meaning of the DM-RS antenna port needs to be extended. When DM-RS antenna ports in two resource elements (REs) are the same, channels may be derived from each other.

In the absence of separate RRC signaling, even when DM-RS antenna ports for different PUSCH instances are the same in the same slot or in different slots, the UE may generate PUSCH instances independent of each other. When separate RRC signaling is performed (eg, when method 2.2-1 is used), the UE may maintain phase/power continuity in all or some PUSCH instances belonging to a PUSCH occasion.

로 정의될 수 있고, 채널의 응답은

로 정의될 수 있다. 이 경우, 기지국에서 수신된 신호는

로 정의될 수 있다. 여기서,

은 잡음일 수 있고, i는 PUSCH 인스턴스의 인덱스일 수 있다. "단말이 경계 영역에 위치하고, 채널의 응답이 모든 PUSCH 인스턴스들(예를 들어, i)에 대해 거의 변하지 않는 경우", 조인트 추정(joint estimation) 동작은 적용될 수 있다. j≠i를 만족하는 j에 대해서, PUSCH 인스턴스 j와 PUSCH 인스턴스 i 간의 조인트 추정 동작을 위해, DM-RS에서 위상과 전력(예를 들어, 진폭)은 동일할 수 있다. 또는, DM-RS의 위상과 전력이 달라지는 경우, 기지국은 DM-RS의 위상과 전력이 달라지는 값을 알 수 있고, 해당 값에 기초하여 보상 동작을 수행할 수 있다. 그렇지 않은 경우, 유효 채널의 값은 다르게 추정될 수 있다. 이는

로 표현될 수 있다. 따라서 단말은 "

"로 유지할 수 있다. 또는, 기지국이

를 보상할 수 있도록, 단말은 단말과 기지국 간에 설정된 값을 적용할 수 있다. 단말과 기지국 간에 별도의 설정이 필요하지 않도록, 단말이 위상 및 진폭을 유지하는 것이 바람직할 수 있다.For convenience of explanation, the value of DM-RS transmitted by the terminal is

It can be defined as , and the response of the channel is

can be defined as In this case, the signal received from the base station is

can be defined as here,

may be noise, and i may be an index of a PUSCH instance. When "the UE is located in the boundary region and the channel response hardly changes for all PUSCH instances (eg, i)", a joint estimation operation may be applied. For j satisfying j≠i, for a joint estimation operation between PUSCH instance j and PUSCH instance i, the phase and power (eg, amplitude) in DM-RS may be the same. Alternatively, when the phase and power of the DM-RS are different, the base station may know a value at which the phase and power of the DM-RS change, and may perform a compensation operation based on the value. Otherwise, the value of the effective channel may be estimated differently. this is

can be expressed as Therefore, the terminal "

" can be maintained. Alternatively, the base station

To compensate for , the terminal may apply a value set between the terminal and the base station. It may be desirable for the terminal to maintain the phase and amplitude so that a separate configuration between the terminal and the base station is not required.

If N frequency hops are used in a PUSCH occasion, K (nominal) PUSCH instances may be transmitted. In this case, for all PUSCH instances transmitted in frequency hop n (n=1, 2, ..., N), DM-RSs may be generated to have phase continuity. Here, the PUSCH instances share a frequency hop n, but may be transmitted apart from each other in time.

For example, the transmission method of the DM-RS may be indicated to the UE by RRC signaling. Based on one value indicated by RRC signaling, the DM-RS for each frequency hop of PUSCH instances belonging to a PUSCH occasion need not have phase continuity. Based on another value indicated by RRC signaling, if PUSCH instances belonging to a PUSCH occasion belong to the same frequency hop, DM-RSs for the same frequency hop may be generated to have phase continuity.

Method 2.2-2 : The UE may consider the corresponding PUSCH instance(s) as one extended PUSCH instance in order to generate (nominal) PUSCH instance(s) having the same phase/power continuity, A PUSCH instance can be created. Here, the extended PUSCH instance may include (nominal) PUSCH instance(s) corresponding to all or part of PUSCH occasions.

For example, when PUSCH repetition type A is indicated, a case in which K nominal PUSCH instances are transmitted in K slots may be considered. In the K slots, according to the existing method, the UE can nominally generate the PUSCH instance(s) independently, and the base station cannot utilize the DM-RS of the nominal PUSCH instance(s) for the joint estimation operation. When method 2.2-2 is used, K nominal PUSCH instances may be considered as contiguous virtual nominal PUSCH instances (eg, extended PUSCH instances) in the time domain. The UE may jointly perform DM-RS generation and mapping for the extended PUSCH instance. Here, the number of PUSCH instance(s) belonging to the extended PUSCH instance may be K or less than K. For example, the extended PUSCH instance(s) may be transmitted in consecutive slots.

3 is a conceptual diagram illustrating a first embodiment to which PUSCH repetition type A is applied.

Referring to FIG. 3 , PUSCH instance(s) may belong to a PUSCH occasion, PUSCH instance(s) may be generated in an extended PUSCH instance, and then PUSCH repetition type A may be applied. Four PUSCH instances constituting a PUSCH occasion may be created to maintain phase/power continuity. The UE may regard four PUSCH instances as one extended PUSCH instance, and may configure the four PUSCH instances to have the same phase/power.

Method 2.2-3 : In method 2.2-2, the UE may regard the front loaded DM-RS of the first PUSCH instance as the front loaded DM-RS of the extended PUSCH instance in one extended PUSCH instance. In addition, the UE considers "additional DM-RS of the first PUSCH instance" and "front loaded DM-RS and additional DM-RS of the remaining PUSCH instance(s)" as additional DM-RSs of the extended PUSCH instance can do.

In addition, coded data (eg, uplink-shared channel (UL-SCH) or uplink control information (UCI)) may be jointly applied to the extended PUSCH instance. Alternatively, the coded data may be applied separately (eg, per slot or nominally PUSCH instance). This operation may be expressed as performing a rate matching operation based on a nominal PUSCH instance or an extended PUSCH instance.

Method 2.2-4 : In method 2.2-2, the UE may derive a transport block (TB) size from one reference PUSCH instance or reference PUSCH instance(s) for an extended PUSCH instance, and different redundancy version (RV) ) ) or encoded UCI (or extended UCI) may be mapped for each PUSCH instance or PUSCH instance(s).

For example, data for PUSCH instance 1 shown in FIG. 3 may be mapped from coded data having RV a in a circular buffer, and PUSCH instance 2 may be mapped from coded data having RV b. can This operation can be regarded as applying method 2.2-4. Accordingly, the UE may perform the DM-RS generation operation based on the extended PUSCH instance, but the data/UCI mapping operation may be performed based on the PUSCH instance.

Method 2.2-5 : In method 2.2-2, the UE may derive a TB size from one reference PUSCH instance or reference PUSCH instance(s) for an extended PUSCH instance, and to the first PUSCH instance of the extended PUSCH instance Encoded data or coded UCI (eg, extended UCI) with an associated RV may be newly mapped.

For example, data for the extended PUSCH instance shown in FIG. 3 may be nominally mapped independently of the PUSCH instance. When the first nominal PUSCH instance starts from RV a, data for the extended PUSCH instance may start from coded data having RV a in the circular buffer. Correspondence to all REs belonging to the PUSCH instance extended in the circular buffer may be established. Data/UCI may be nominally mapped independent of PUSCH instances. Therefore, the UE may perform not only the DM-RS generation operation but also the data/UCI mapping operation based on the extended PUSCH instance.

In order to process the extended PUSCH instance, a larger amount of memory may be required in the UE. Here, the memory may be distinguished from the circular buffer. A rate matching operation may be performed in a circular buffer, and after the rate matching operation, symbols resulting from the modulation operation (eg, Quadrature Amplitude Modulation (QAM)/Phase Shift Keying (PSK) symbols) are time and frequency resources can be mapped to In the mapping step between the symbol and the physical resource, the corresponding symbol may be stored in the memory of the terminal.

The UE may process TB/UCI in units of the extended PUSCH instance, and the processing result may be stored in the memory. When the memory size of the UE is limited, the configuration of the extended PUSCH instance may be restricted according to the memory size.

Method 2.2-6 : Depending on the capability of the UE, the combinations of which the extended PUSCH instance can be configured may be limited.

The larger the size of the TB to be transmitted in the PUSCH occasion, the more the memory of the UE may be required. The larger the number of nominal PUSCH instances belonging to the extended PUSCH instance, the more memory may be required. In addition, as the number of repetitions of the PUSCH and the number of additional DM-RSs increases, the number of DM-RS symbols jointly generated by the UE may increase. Therefore, the base station may limit the nominal maximum number of PUSCH instances belonging to the extended PUSCH instance in consideration of the terminal capability.

The terminal capability for the extended PUSCH instance may be reported to the base station through higher layer signaling. Considering the size of the TB that the UE intends to receive in the PUSCH occasion, the nominal number of symbols in the PUSCH instance, the number of symbols in the PUSCH occasion, and/or the number of DM-RS symbols, the base station performs the extended PUSCH instance The maximum number of may be informed to the terminal through higher layer signaling. Alternatively, the maximum number of extended PUSCH instances may be defined in a technical standard. When the maximum number of extended PUSCH instances is indicated in the technical standard, the nominal number of PUSCH instances constituting the extended PUSCH instances may be determined according to the above-described conditions. When the maximum number of extended PUSCH instances is indicated in higher layer signaling, the nominal maximum number of PUSCH instances is indicated to the UE by scheduling DCI, activating DCI and/or RRC signaling for allocating PUSCH occasions. can be

Method 2.2-7 : Nominal PUSCH instances belonging to a PUSCH occasion may belong to one or more extended PUSCH instances, and the extended PUSCH instance(s) is the size of the extended PUSCH instance(s) (eg, a nominal PUSCH instance) ) can be sorted in ascending or descending order.

When the UE is instructed to perform repeated PUSCH transmission K times, the PUSCH instance may be nominally repeated K times. When the terminal capability supports the joint DM-RS estimation operation, extended PUSCH instance(s) may be configured, and the extended PUSCH instance(s) may configure a PUSCH occasion. According to method 2.2-6, the terminal capability can be further subdivided. When the UE capability is sufficient, one extended PUSCH instance may be configured. If the UE capability is not sufficient, two or more extended PUSCH instances may be configured. Each of the extended PUSCH instances is J ₁ , J ₂ , J ₃ , … It may contain two nominal PUSCH instances. According to the method from 2.2 to 7, it can be defined as _{"J 1 ≤J 2 ≤J 3 ≤} ..." or _{"J 1 ≥J 2 ≥J 3 ≥} ...".

For example, if the PUSCH occasion is repeated 4 times, "the terminal capability, the size of the TB, and/or the configuration of the additional DM-RS", "the number of symbols that the nominal PUSCH instance has", or "the PUSCH occasion is Depending on the "total number of symbols with", 4 nominally PUSCH instances can maintain phase/power continuity. Alternatively, two nominal PUSCH instances may maintain phase/power continuity to configure one extended PUSCH instance, and the number of the aforementioned extended PUSCH instances may be two.

For example, if the PUSCH occasion is repeated 6 times, "the terminal capability, the size of the TB, and/or the configuration of additional DM-RS", "the number of symbols that a nominal PUSCH instance has", or "the PUSCH occasion is Depending on the "total number of symbols with", 6 nominal PUSCH instances can maintain phase/power continuity. Alternatively, four nominal PUSCH instances may configure one extended PUSCH instance to maintain phase/power continuity, and two nominal PUSCH instances may configure one extended PUSCH instance.

2.2.1 How to apply OCC (Orthogonal Cover Code) to DM-RS of PUSCH instance

Method 2.2-8 : In transmission of PUSCH occasion, OCC may be applied to DM-RS of PUSCH instances.

A comprehensive channel estimation operation (eg, joint estimation operation) may be performed by using all DM-RSs of some or all PUSCH instance(s) belonging to a PUSCH occasion. Here, the role of the OCC may be to secure a multiplexing gain with other terminals. DM-RSs of PUSCH instances transmitted by terminals may have OCC, and the base station may perform joint estimation for PUSCH occasions. It may be desirable for the UE to transmit the PUSCH occasion to have phase continuity.

The OCC may be generated by a Walsh code or a Discrete Fourier Transform (DFT) code. For convenience of description, the codeword of the OCC may be delivered to the terminal as an OCC index. The codeword of OCC may have as many coded symbols as the length of OCC. When the OCC is generated by the Walsh code, the coded symbol may be expressed as -1/+1 or 0/1. When the OCC is generated by the DFT code, the coded symbol may be expressed as a complex number constituting an n-th root of unity. Here, n may be the length of the OCC.

Method 2.2-9 : When method 2.2-8 is applied, the length of the OCC given to the UE may correspond to the number of PUSCH instances (eg, actual PUSCH instances) in the PUSCH occasion.

The coded symbols of OCC may be applied to DM-RS symbols belonging to an actual PUSCH instance. When two actual PUSCH instances are configured, the length of the OCC may be m. In this case, the plurality of DM-RS symbols may belong to the j-th actual PUSCH instance. The j-th coded symbol of OCC (j=1,2,...,m) may be commonly multiplied.

4 is a conceptual diagram illustrating a first embodiment of a method of applying OCC in units of actual PUSCH instances.

Referring to FIG. 4 , OCC may be applied to an actual PUSCH instance in a PUSCH occasion. Since the PUSCH instance is transmitted 4 times in (a) shown in FIG. 4 , the length of the OCC may be 4. Since the PUSCH instance is transmitted 6 times in (b) of FIG. 4 , the length of the OCC may be 6.

Method 2.2-9 : When a PUCCH occasion is transmitted, the actual number of PUSCH instances may be any natural number. When the OCC is generated by a Walsh code, it may be convenient for the length of the OCC to be defined as a power of two. Therefore, it may be preferable that the length of the OCC has a specific structure rather than an arbitrary natural number.

Method 2.2-10 : When method 2.2-8 is applied, the length of the OCC given to the UE may correspond to the number of slots required for transmission of the PUSCH occasion.

According to a slot transmitted in a PUSCH occasion, an OCC coded symbol may be applied. Even when a plurality of actual PUSCH instances are transmitted in one slot, the same coded symbols of OCC may be applied.

5 is a conceptual diagram illustrating a first embodiment of a method of applying OCC in units of slots.

Referring to FIG. 5 , the terminal may perform transmission based on method 2.2-10. In (a) shown in FIG. 5, a predefined interval (eg, a slot) between PUSCH instances may exist. In (b) shown in FIG. 5, there may not be an interval between PUSCH instances. Since the OCC coded symbol is reflected for each slot, the DM-RS in (b) shown in FIG. 5 may be determined by applying the same OCC coded symbol to two or more PUSCH instances. Here, the length of the OCC may be 4. The length of the OCC may be defined as the number of slots in which the PUSCH occasion is transmitted. For example, when PUSCH repetition type A is used, the number of repetitions may correspond to the length of the OCC. When PUSCH repetition type B is used, the number of slots may be derived from the length of a time window. The number of slots may correspond to the length of the OCC.

2.2.2 Example of PUCCH: DM-RS

The above-described methods (eg, embodiments) may be applied to not only PUSCH transmission but also physical uplink control channel (PUCCH) transmission. According to the transmission method of the PUCCH occasion, the phase continuity (or phase coherence) and power continuity (or power coherence) of the PUCCH DM-RS may be maintained.

For example, the extended PUCCH instance in the PUSCH occasion may be configured according to the TB size, but the extended PUCCH instance in the PUCCH occasion may be configured according to the amount of UCI and/or the number of symbols that the PUCCH instance has. .

The terminal capability for the extended PUCCH instance may be reported to the base station by higher layer signaling. Considering “the amount of UCI to be received from the UE in the PUCCH occasion”, “the number of symbols of the PUCCH instance”, “the number of symbols of the PUCCH occasion”, and/or “the number of DM-RS symbols” , the base station may inform the terminal of the maximum number of extended PUCCH instances through higher layer signaling. Alternatively, the maximum number of extended PUCCH instances may be indicated in the technical specification. When the maximum number of extended PUCCH instances is indicated in the technical specification, the number of PUCCH instances constituting the extended PUCCH instance may be determined according to the above-described condition. When the maximum number of extended PUCCH instances is indicated in higher layer signaling, the maximum number of PUCCH instances may be indicated to the UE by scheduling DCI, activation DCI, and/or RRC signaling for allocating PUCCH occasions.

When the UE is instructed to perform K repeated PUCCH transmissions, the PUCCH instance may be repeated K times. If the terminal capability supports the joint DM-RS estimation operation, a PUCCH instance may be configured. The terminal capability may be further subdivided. If the terminal capability is sufficient, one extended PUCCH instance may be configured, and the extended PUCCH instance(s) may constitute a PUCCH occasion. If the terminal capability is not sufficient, two or more extended PUCCH instances may be configured. Each of the extended PUCCH instances is J ₁ , J ₂ , J ₃ , … may include PUCCH instances. It may be defined as “J ₁ ≤J ₂ ≤J ₃ ≤…” or “J ₁ ≥J ₂ ≥J _{3 ≥…”.}

The UE may transmit a PUSCH occasion. Transmission of the PUCCH occasion by the terminal may be indicated by the base station. In this case, the multiplexing operation of PUCCH and PUSCH may be performed. "If the PUCCH occasion includes one PUCCH instance and the PUCCH instance is not repeated", the PUSCH instance may overlap some symbols of the PUCCH in the time domain. In this case, in consideration of the processing time of the UE, UCI may be multiplexed in the PUSCH instance, and the PUCCH instance may not be transmitted. That is, UCI may be transmitted in a PUSCH instance instead of a PUCCH instance.

In some PUSCH instances belonging to PUSCH occasions, UCI as well as TB may be transmitted. In this case, in order to support the joint DM-RS estimation operation, it may be desirable to maintain the transmit power and/or phase continuity regardless of the amount of UCI in order to determine the transmit power of the extended PUSCH instance.

2.3 How to improve in the time domain

The base station may indicate the PUSCH repetition type A or the PUSCH repetition type B to the UE through RRC signaling. The UE may repeatedly transmit the PUSCH based on the PUSCH repetition type indicated by the base station. When PUSCH repetition type A is used, the UE may transmit one or more PUSCHs. The minimum interval between first symbols in adjacent PUSCH transmissions may be one slot. When PUSCH repetition type B is used, the UE may transmit two or more PUSCHs. The minimum interval between first symbols in adjacent PUSCH transmissions may be the number of symbols included in the PUSCH. PUSCH repetition type A may be used to widen a coverage area, and the UE may perform repeated transmission according to PUSCH repetition type A. PUSCH repetition type B may be used to reduce an error rate and/or delay time, and the UE may perform repetitive transmission according to PUSCH repetition type B. For convenience of description, “PUSCH transmitted once” may be referred to as a “PUSCH instance”, and one PUSCH occasion may consist of one or more PUSCH instances.

In a communication system supporting time division duplex (TDD), the number of UL symbols and / or FL symbols is "slot pattern", "Type0-PDCCH Common search space set and CORESET (control resource set) settings" and / or " According to the "synchronization signal/physical broadcast channel (SS/PBCH) block pattern", it may be less than the number of symbols of the PUSCH instance. When PUSCH repetition type A is used, a PUSCH instance may not be transmitted, and a PUSCH instance that has not been transmitted may not be transmitted later. The number of repetitions of the PUSCH may not be readjusted, and the corresponding PUSCH instance may be considered transmitted. When PUSCH repetition type B is used, a PUSCH instance may be split into split PUSCH instances, and split PUSCH instances may be transmitted. A split PUSCH instance may have a DM-RS.

When repeated transmission according to PUSCH repetition type A is performed in a communication system supporting TDD, PUSCH instances may not be transmitted in some slots. The base station may perform dynamic scheduling for retransmission of a PUSCH instance that has not been transmitted. When there are many terminals to extend the reach area, many PDCCHs may be required. To solve this problem, an improved PUSCH repetition type A may be needed.

For convenience of description, the improved PUSCH repetition transmission may be referred to as PUSCH repetition type C. PUSCH repetition type C may be used for the purpose of extending the coverage area. When PUSCH repetition type C is used, PUSCH instances may be transmitted in units of slots. In order to save the amount of PDCCH, the transmission number of PUSCH instances may be guaranteed.

Method 2.3-1 : When PUSCH repetition type C is used, PUSCH instances may be transmitted in units of slots, and PUSCH instances may be transmitted in non-consecutive slots so that the number of PUSCH repetitions is guaranteed.

In a communication system supporting TDD, slot pattern information may be transmitted to the terminal through RRC signaling and/or a slot format indicator (SFI). The PUSCH occasion may be scheduled using a UL grant or RRC signaling. A slot in which the first PUSCH instance is transmitted in a PUSCH occasion may be indicated by a UL grant or RRC signaling.

In order to satisfy the number of PUSCH repetitions (eg, K) indicated by RRC signaling, the UE may check whether the PUSCH instance can be transmitted in the slot in which the first transmission starts or in consecutive slots after the corresponding slot. When UL symbols and/or FL (flexible) symbols are insufficient according to a slot pattern, the UE may not be able to transmit a PUSCH instance. Except for slots in which PUSCH instances cannot be transmitted, K PUSCH instances may be transmitted in non-consecutive slots.

For example, a case in which 4 PUSCH instances are indicated to be repeatedly transmitted in a PUSCH occasion may be considered.

6 is a conceptual diagram illustrating a first embodiment of a PUSCH transmission method according to PUSCH repetition type C. Referring to FIG.

Referring to FIG. 6 , a PUSCH instance may be transmitted 4 times in 5 slots. The time interval between PUSCH instances may be Δ. Δ may be represented by one slot (eg, 14 symbols or 12 symbols). A PUSCH instance may have the same Start and Length Indicator Value (SLIV) in a slot. The fourth slot may be considered a time when the SLIV is not valid (eg, an invalid resource). In this case, the fourth PUSCH instance may be transmitted in the fifth slot.

According to method 2.3-1, PUSCH instances transmitted in the slot may always have the same SLIV and mapping type. In this case, according to the slot pattern, many slots may be required to transmit the PUSCH instance K times. Accordingly, it may be desirable for a PUSCH instance belonging to a PUSCH occasion to have two or more SLIV and mapping types.

For convenience of description, the improved PUSCH repetition transmission may be referred to as PUSCH repetition type D. PUSCH repetition type D may indicate various time resources by UL grant and/or RRC signaling.

Method 2.3-2 : When PUSCH repetition type D is used, PUSCH instances may be transmitted in units of slots, and a Time Domain Resource Assignment (TDRA) index applied to K consecutive slots may be indicated.

PUSCH occasions may be scheduled using UL grants and/or RRC signaling. Here, the value of K may be set by RRC signaling. Alternatively, the value of K may be indicated by the number of SLIV and/or mapping types included in UL grant and/or RRC signaling. That is, the value of K can be dynamically indicated.

The UL grant and/or RRC signaling may indicate that the PUSCH instance is transmitted K times, and the TDRA index may indicate K SLIVs and/or mapping types. Alternatively, when fewer than K SLIVs and/or mapping types are indicated, it may be interpreted that K SLIVs and/or mapping types are indicated according to a predefined method. For example, when a PUSCH is to be transmitted eight times, if four SLIVs and/or mapping types are indicated, the same four SLIVs and/or mapping types may be applied again in order. Alternatively, if more than K SLIVs and/or mapping types are indicated, K SLIVs and/or mapping types may be applied from the first SLIV and/or mapping type.

For example, a case in which repeated transmission of 4 PUSCH instances is indicated in a PUSCH occasion may be considered.

7 is a conceptual diagram illustrating a first embodiment of a PUSCH transmission method according to PUSCH repetition type D. Referring to FIG.

Referring to FIG. 7 , a PUSCH instance may be transmitted 4 times in 4 slots. In the PUSCH occasion allocation procedure, (SLIV1, SLIV2, SLIV3, SLIV4) may be indicated to the UE. Each of the corresponding SLIVs may be interpreted as a SLIV of each PUSCH instance. In the fourth slot, SLIV4 may be regarded as belonging to an invalid time (eg, an invalid resource). Therefore, the fourth PUSCH instance may not be transmitted.

As another example, the K SLIVs may be interpreted in order. The UE may determine whether the first SLIV is applied. If the first SLIV cannot be applied, the UE may determine whether to apply the second SLIV. The UE may check the applicable SLIV by repeating the above-described operation, and may map the PUSCH instance according to the applicable SLIV. Here, the meaning of “applicable SLIV” may mean “transmission of a full PUSCH instance composed of valid symbols is possible”. The UE may select the minimum number of valid SLIV(s) in consideration of the order from among the SLIVs (eg, SLIV vectors) indicated to the UE.

8 is a conceptual diagram illustrating a second embodiment of a PUSCH transmission method according to PUSCH repetition type D. Referring to FIG.

Referring to FIG. 8 , a PUSCH instance may be transmitted 3 times in 4 slots. SLIV1 may be applicable in the first slot and the second slot. Considering invalid symbols, SLIV1 and SLIV2 may not be applied in the third slot. Therefore, SLIV3 may be applied in the third slot. In the fourth slot, SLIV1, SLIV2, and SLIV3 may not be applied. Therefore, SLIV4 may be applied in the fourth slot.

Method 2.3-3 : To comply with method 2.3-1 and/or method 2.3-2, the UL grant may include one new data indicator (NDI) and RV. Alternatively, when a plurality of NDIs and RVs are included in a UL grant to schedule two or more TBs, the combination of specific field(s) included in the corresponding UL grant may imply that one TB is scheduled by the UE. .

Method 2.3-4 : According to method 2.3-1 and/or method 2.3-2, the value of K may be indicated by RRC signaling. In this case, even when the UL grant includes a plurality of NDIs and RVs, the UE may transmit a PUSCH occasion using one NDI and RV among the plurality of NDIs and RVs.

When two or more PUSCH instances are transmitted in a PUSCH occasion, different RVs may be mapped to each PUSCH instance. The start value of RV may be indicated by DCI or RRC signaling for allocating PUSCH occasions, and other values of RV may be determined based on one sequence indicated by RRC signaling among sequences defined in the technical standard. . Alternatively, one of the above-described sequences may be defined in a technical standard, and in this case, an RRC signaling operation for indicating another value of RV may not be performed.

For convenience of description, the improved PUSCH repetition transmission may be referred to as PUSCH repetition type E. When PUSCH repetition type E is used, various time resources may be indicated by UL grant and/or RRC signaling. PUSCH repetition type E may be applied to PUSCH occasions allocated to exceed a boundary of a slot. When "PUSCH repetition type E is used and a PUSCH occasion is transmitted in two or more slots", a start symbol to which a PUSCH instance can be mapped may be explicitly indicated for each slot.

Method 2.3-5 : When PUSCH repetition type E is used, a TDRA index applied in K consecutive slots may be indicated.

"Transmission of PUSCH instances in K slots" may be configured by UL grant and/or RRC signaling, and the TDRA index may indicate K SLIVs and/or mapping types. Alternatively, if fewer than K SLIVs and/or mapping types are indicated, it may be interpreted that K SLIVs and/or mapping types are indicated based on a predefined method.

Alternatively, K start symbol indexes (S), one length (L), and/or mapping types may be derived through UL grant and/or RRC signaling. Here, the start symbol index (S) and length (L) may be indicated by SLIV. The UE may recognize the start symbol index (S), the length (L), and/or the mapping type based on the first SLIV. The UE may recognize the start symbol index (S) based on the second SLIV and the SLIV(s) after the second SLIV.

2.3.1 Improvement of reinterpretation method of time window

For convenience of description, the improved PUSCH repetition transmission may be referred to as PUSCH repetition type BB. PUSCH repetition type F may be similar to PUSCH repetition type B. The interpretation method of the time window in PUSCH repetition type F may be different from the interpretation method of the time window in PUSCH repetition type B.

When PUSCH repetition type BB is used, regardless of slot format, invalid symbol(s), SSB, or Type0-PDCCH CSS set, the length of the time window may be regarded as a symbol equal to the length of the PUSCH instance and the number of repetitions. have. The index of the start symbol of the time window may be the index of the start symbol in which the PUSCH occasion is located. Thereafter, according to the slot format, invalid symbol(s), SSB, or Type0-PDCCH CSS set, a symbol in which a PUSCH occasion cannot be transmitted (eg, an invalid symbol) and a symbol in which a PUSCH occasion can be transmitted (eg, valid symbols) may be distinguished. A PUSCH occasion may be transmitted in a valid symbol among symbols within a time window.

The method of the base station indicating the time window to the terminal may be maintained the same as that of PUSCH repetition type B, and the interpretation method of the time window may be changed. A guaranteed number of symbols may be used in the PUSCH occasion transmitted by the UE. Therefore, the PUSCH occasion can be utilized in a wider area.

Method 2.3-6 : When PUSCH repetition type BB is used, the time window may be interpreted as follows. The time window may be interpreted as the number of symbols in which PUSCH occasions may be transmitted. When a PUSCH occasion is transmitted, a DM-RS may be allocated for each actual PUSCH instance.

The enhanced time window may include only valid symbols. An actual PUSCH instance may be transmitted in an invalid symbol within a PUSCH occasion. In this case, the actual PUSCH instance may include a DM-RS.

9A is a conceptual diagram illustrating a first embodiment of a method for analyzing a time window when PUSCH repetition type B is used, and FIG. 9B is a first embodiment of a method for analyzing a time window when PUSCH repetition type BB is used. is a conceptual diagram showing

Referring to FIG. 9A , the time window may be determined based on SLIV (eg, S, L) and/or K, and valid symbol(s) may be selected after the time window is determined. Referring to FIG. 9B , valid symbol(s) may be selected first, and after the valid symbol(s) are selected, a time window may be determined based on SLIV (eg, S, L) and/or K.

Method 2.3-7 : The first symbol (eg, modulation symbol) of an actual PUSCH instance may be transmitted in a valid symbol located after the invalid symbols. That is, the first symbol of an actual PUSCH instance may be located in a valid symbol.

When PUSCH repetition type B is used, PUSCH transmission may be performed on valid symbols. In this case, the time window may be maintained as it is. Therefore, in the embodiment shown in FIG. 9A , a nominal PUSCH instance may be transmitted in period 0, and an actual PUSCH instance may be transmitted in period 1, period 2, and period 3.

On the other hand, when the PUSCH repetition type BB is used, the time window may be defined only in valid symbols. In this case, the number of symbols actually occupied by the PUSCH occasion may be greater than L×K. In the embodiment shown in FIG. 9B , a PUSCH instance may be nominally transmitted in period 0. After period 0, the PUSCH instance may be nominally transmitted again in period 1 excluding the invalid symbol. When valid symbols remain, an actual PUSCH instance may be transmitted in section 2 from the remaining valid symbols to the boundary of the slot. By repeating the above-described operations, the PUSCH instance may be nominally transmitted in sections 3, 4, 5, and 6.

A coded symbol of data (eg, a symbol in which coded bits are modulated) may be mapped to an actual PUSCH instance. In this case, the mapping operation in the circular buffer may start from a new RV. The RV of the nth PUSCH instance and the RV of the n+1th PUSCH instance may have the same value (eg, 0). Alternatively, the RV of the nth PUSCH instance may be different from the RV of the n+1th PUSCH instance.

For example, in section 0 shown in FIG. 9B , a PUSCH instance may correspond to RV 0, and in section 1, a PUSCH instance may correspond to RV 1. By repeating the above-described operations, the PUSCH instance may correspond to the RV. In the case of "when RV consists of only zeros" or "when RV consists of only zeros and two", the same method as the above-described method may be applied.

Method 2.3-8 : DM-RS may be mapped to each PUSCH instance.

An actual PUSCH instance may always have a DM-RS. This operation may help the base station to ensure the quality of the channel estimation at the stage of data reception. For example, the base station may estimate a channel by performing a joint estimation operation, and may perform a reception operation of concatenated real PUSCH instances based on the estimated channel. When a DM-RS is mapped to a PUSCH instance, there may be few symbols to which data is mapped in the corresponding PUSCH instance. In order to solve this problem, the following methods can be considered.

Method 2.3-9 : DM-RS may not be mapped to some PUSCH instances. When the number of symbols allocated for data among the symbols of the PUSCH instance is small, the effective code rate may be greater than or equal to a predefined threshold. In this case, the DM-RS may be dropped, and data may be mapped to the PUSCH instance instead of the DM-RS.

In order to determine whether to allocate the DM-RS, the UE may assume that the DM-RS is virtually allocated, and may calculate a code rate based on the above-mentioned assumption. When the calculated code rate is greater than or equal to a threshold defined in the technical standard (eg, effective code rate = 0.95), the UE may not allocate the DM-RS to the PUSCH instance. After determining whether DM-RS is allocated, the UE may map the coded symbols (eg, modulation symbols) of data to a resource grid.

2.4 How to improve power control

The same transmit power control (TPC) command may be applied to all PUSCH instance(s) belonging to a PUSCH occasion. Since the number of symbols in each of the PUSCH instances may be different, the PUSCH instances may not have the same transmit power.

Transmission power applied to the PUSCH instance may be calculated based on the equation defined in the technical standard. For example, the transmit power applied to the PUSCH instance may be calculated based on Equation 2 below.

P(i,j,q,l) may be applied to PUSCH instance i. j may be a set of parameters for calculating power. q may be an index of a downlink-reference signal (DL-RS) used by the UE to estimate path attenuation or an index of an uplink-reference signal (UL-RS). l may be an index of a set managing TPC commands.

P _o (j) may be a variable that is a criterion for transmission power for a PUSCH instance. A value for the j- th power control parameter may be indicated by RRC signaling. μ may be a variable for the subcarrier interval used by the PUSCH instance. α( j ) may be a variable related to the compensation magnitude of path attenuation for the j-th power control loop. α( j ) may be indicated by RRC signaling. PL(q) may be the magnitude of the DL path attenuation calculated based on q when the reference RS is q. PL(q) may be a value measured by the terminal and/or an estimated value. f(i,l) may be an accumulated value of TPC commands for the l-th power control loop.

"이 지시될 수 있다. 여기서, BPRE(bits per RE)는 부호율과 관련된 변수일 수 있다. PUSCH 인스턴스에서 TB가 맵핑되는 경우에 BPRE는 PUSCH 인스턴스에서 TB 없이 비주기(aperiodic) CSI(channel state information)만이 맵핑되는 경우에 BPRE와 다르게 계산될 수 있다. PUSCH 인스턴스가 TB를 포함하는 경우, "

"가 정의될 수 있다. PUSCH 인스턴스가 TB를 포함하지 않는 경우, "

"가 정의될 수 있다. 여기서, β는 부호율의 오프셋에 관련된 변수일 수 있다. PUSCH 인스턴스에서 TB가 맵핑되는 경우에 β는 PUSCH 인스턴스에서 TB 없이 비주기 CSI만이 맵핑되는 경우에 β와 다르게 계산될 수 있다.Here, the value of Δ(i) may be fixed to 0 according to a value indicated by RRC signaling. Alternatively, the value of Δ(i) may be calculated as a different value according to a value indicated by RRC signaling. When a PUSCH instance is transmitted through two or more MIMO layers, regardless of RRC signaling "Δ(i)=0" may be indicated. When a PUSCH instance is transmitted through one MIMO layer, "Δ(i)=0" may be indicated by RRC signaling. Or, when the PUSCH instance is transmitted through one MIMO layer, by RRC signaling

" may be indicated. Here, bits per RE (BPRE) may be a code rate-related variable. When a TB is mapped in a PUSCH instance, the BPRE is an aperiodic channel state (CSI) without a TB in the PUSCH instance. information) can be calculated differently from BPRE when only mapped. When the PUSCH instance includes a TB, "

" may be defined. If the PUSCH instance does not include a TB, "

" may be defined. Here, β may be a variable related to an offset of a code rate. When TB is mapped in the PUSCH instance, β is calculated differently from β when only aperiodic CSI without TB is mapped in the PUSCH instance. can be

"가 정의될 수 있다. M _RB (i)는 PUSCH 인스턴스가 맵핑되는 RB의 개수일 수 있다. N _sym (i)는 PUSCH 인스턴스에 속하는 심볼의 개수일 수 있다. N _sc (i,j)는 PUSCH 인스턴스가 맵핑되는 심볼 j가 갖는 부반송파들 중에서 DM-RS와 PT(phase tracking)-RS가 매핑되는 부반송파들을 제외한 나머지 부반송파들의 개수를 의미할 수 있다. Q는 PUSCH 인스턴스에 적용되는 변조율을 의미할 수 있다. R는 PUSCH 인스턴스에 적용되는 부호율을 의미할 수 있다.When the PUSCH instance includes a TB, “β=1” may be defined. When the PUSCH instance does not include a TB, β may be one value indicated by a UL grant or RRC signaling among values indicated by RRC signaling. C may mean the number of code blocks included in the PUSCH instance, and K _r may mean the size of the r- th code block (eg, the number of bits). N _RE may be a variable related to the number of REs of a PUSCH instance. "

" may be defined. M _RB (i) may be the number of RBs to which the PUSCH instance is mapped. N _sym (i) may be the number of symbols belonging to the PUSCH instance. N _sc (i, j) is It may mean the number of remaining subcarriers excluding subcarriers to which DM-RS and PT (phase tracking)-RS are mapped among the subcarriers of symbol j to which the PUSCH instance is mapped Q means the modulation rate applied to the PUSCH instance R may mean a code rate applied to a PUSCH instance.

The above-described parameters may be divided into an open loop control parameter and a closed loop control parameter. For example, the UE may update PL(q) by measuring the path attenuation by itself. PL(q) may be an open loop control parameter. For example, the terminal may update f(i,l) based on the received TPC command. f(i,l) may be a closed loop control parameter.

Method 2.4-1 : Transmission power applied to a PUSCH instance may be derived according to a technical standard (eg, Equation 2).

For example, different bandwidths and/or different numbers of symbols may be allocated to each PUSCH instance belonging to a PUSCH occasion. Based on Equation 2, each of the PUSCH instances may have different power. The PUSCH instance may belong to a slot (or subframe) to which a new timing advance (TA), TPC command, or path attenuation is applied. In this case, TA, TPC command, or path attenuation may be applied differently in adjacent PUSCH instances.

Method 2.4-2 : A transmit power applied to a PUSCH instance may be derived from a reference PUSCH instance, and a PUSCH occasion may be transmitted by reusing the derived transmit power. For example, the transmission power of the PUSCH instance may be the same as the transmission power of the reference PUSCH instance.

For example, the transmission power applied to the first PUSCH instance belonging to the PUSCH occasion may be equally applied to the remaining PUSCH instance(s). As another example, the transmission power applied to the longest PUSCH instance belonging to the PUSCH occasion may be equally applied to the remaining PUSCH instance(s). The UE may allocate the same transmission power to symbols belonging to the PUSCH instance based on the above-described method.

As another method, since the number of symbols ( N _sym (i) ) of the PUSCH instance may be changed, the UE may unify only the variable for the number of symbols. For example, the UE can expect the same Δ(i) to be used.

Method 2.4-3 : With respect to transmission power applied to the PUSCH instance, the UE may assume that “Δ(i)=0” is indicated.

For example, with respect to a continuous transmission method in a PUSCH occasion (eg, FIGS. 6, 7, and 8 ), method 2.4-2 may be applied. In addition, it is preferable that the UE not update both the open-loop control parameter and the closed-loop control parameter for all PUSCH instances belonging to the PUSCH occasion. This will be explained in Method 2.4-4 below.

Method 2.4-4 : For transmit power applied to a PUSCH instance, the UE may not update PL(q) and f(i,l).

2.4.1 When UL occasions (eg, PUSCH occasions and/or PUCCH occasions) overlap in some slots (eg, mini-slots)

The transmission power of PUSCH instances constituting the PUSCH occasion needs to be maintained the same or similar. When the UE transmits two or more PUSCH occasions to the base station, power control in the two or more PUSCH occasions may be different from each other. In this case, maintaining coherence can be difficult.

The same problem may occur in PUCCH occasions. The UE may transmit the PUCCH occasion while transmitting the PUSCH occasion. In embodiments, the UL occasion may mean a PUSCH occasion and/or a PUCCH occasion, and the UL instance may mean a PUSCH instance and/or a PUCCH instance. UL instances may have a predefined interval (eg, a slot).

The transmit power of the UL occasion may be derived based on the method(s) proposed in Section 2.4 and/or Section 3.3 to be described below. To maintain coherence while transmitting UL occasions, it may be desirable for the same transmit power to be used. In order to maintain coherence while transmitting UL occasions, it may be desirable for the transmit power to remain within a predefined error. Accordingly, in the UL occasion, the transmit power may be determined based on one UL instance (eg, the reference UL instance), and the transmit power of the remaining UL instance(s) is the same as the transmit power determined based on the reference UL instance or may be similar.

A period in which the terminal can maintain coherence (hereinafter, referred to as a "coherence period") may be determined according to the capability of the corresponding terminal. The base station may inform the terminal of information on the coherence section by using RRC signaling. The coherence interval may be set in units of symbols. Although the frequency aspect of the coherence section is emphasized in Method 2.5-2, which will be described later, the coherence section can also be utilized in terms of power. Here, the coherence period may be longer than the time during which the UL occasion is transmitted. Alternatively, the coherence period may be less than or equal to the time during which the UL occasion is transmitted.

10 is a conceptual diagram illustrating a first embodiment of a method for a terminal to transmit two or more UL occasions.

Referring to FIG. 10 , the UE may transmit UL occasion 1 and UL occasion 2 . The UE may transmit UL occasion 2 before completion of transmission of UL occasion 1. In this case, the transmit power (eg, P1 and P2) and coherence (eg, phase continuity or power coherence) allocated to UL occasion i (i=1,2) belong to UL occasion i. It may be determined based on UL instances, slot pattern and/or terminal capability. Each of the transmit power and coherence applied to the UL instance belonging to UL occasion 1 may be different from the transmit power and coherence applied to the UL instance belonging to UL occasion 2. Therefore, it may be difficult for the terminal to maintain coherence. However, when the same power is allocated to UL occasion 1 and UL occasion 2, coherence may be maintained in UL occasion 1 and UL occasion 2.

Since the base station allocates the UL occasion to the terminal, it may be implemented so that the above-described situation does not occur for the PUSCH occasion allocated by the dynamic grant or the PUCCH occasion for transmitting the HARQ-ACK for the PDSCH. "When a CG (configured grant) PUSCH exists in the UL occasion" or "When a PUCCH occasion in which HARQ-ACK for semi-persistence scheduling (SPS) PDSCH is transmitted is involved", the terminal maintains coherence A separate specification may be required for this purpose.

Method 2.4-5 : If UL occasion 2 is transmitted before completion of transmission of UL occasion 1, coherence for UL occasion 1 and UL occasion 2 cannot be assumed.

When the transmit power is changed from P1 to P2, coherence may not be maintained. In this case, it may be desirable for the base station to schedule transmission of UL occasion 2 after completion of transmission of UL occasion 1. Method 2.4-5 can be easily applied to UL occasions by dynamic grant.

It may be difficult to apply method 2.4-5 to UL occasions by configured grant (CC). The reason is that when it is determined that data does not exist in the terminal (eg, when the MAC layer does not deliver the TB to the PHY layer), the PUSCH transmission operation may not be performed. Therefore, by applying Method 2.4-5 or Method 2.4-6 below, it may be desirable to maintain coherence for UL Occasion 1.

Method 2.4-6 : New UL occasion 2 may not be transmitted before completion of transmission of UL occasion 1 .

The UE may assume that UL occasion 2 is not scheduled before transmission of UL occasion 1 is completed. Alternatively, the UE may receive scheduling information and/or configuration information for UL occasion 2, but may not transmit UL occasion 2 before completion of transmission of UL occasion 1. For example, the UE may not transmit a configured PUSCH occasion. The UE may not transmit the PUCCH occasion including the scheduling request.

UL occasions having different priorities may be treated as an exception in method 2.4-6. The different priorities may be the priority of the eMBB traffic and the priority of the URLLC traffic. In the same traffic, the priority of UCI and the priority of data may be considered.

Method 2.4-7 : UL occasions having the same priority may be scheduled in the UE. In this case, the UE may transmit UL occasions having the same priority. In the transmission procedure of UL occasion 2 with high priority, new transmission may be allowed. Coherence of UL occasion 2 may be maintained, but coherence of UL occasion 1 may not be maintained.

The UE may distinguish that UL occasion 1 and UL occasion 2 have different priorities. For example, a priority index of eMBB traffic and a priority index of URLLC traffic may indicate different priorities. UL occasion 1 is "PUSCH with priority 0", "PUCCH with priority 0", "SP (semi-persistent) CSI or PUCCH on which periodic CSI is transmitted", and/or "SP CSI or PUSCH on which periodic CSI is transmitted". UL occasion 2 may be "PUSCH with priority 1" and/or "PUCCH with priority 1". UL occasion 1 may be “PUCCH with priority 0”. In this case, coherence of PUCCH may not be maintained by UL occasion 2.

For example, when the priority index of the eMBB traffic is the same as the priority index of the URLLC traffic, the priority of the UCI type may be considered. The priority may be in the order of "HARQ-ACK > scheduling request > CSI part 1 > CSI part 2". The priority of data may be lower than the priority of CSI part 2. Alternatively, the priority of data may be considered to be the same as the priority of CSI part 1. Here, when the priorities are the same, only the property of the first transmitted UL occasion may be maintained. After the UL occasion is transmitted, the UL occasion having the same priority may not be transmitted.

Coherence of UL Occasion 2 may not be maintained according to transmit power. For example, when P1 is different from P2, coherence of UL occasion 2 may not be maintained. To solve this problem, the transmit power of UL Occasion 2 may be adjusted. The transmit power of UL occasion 2 may be adjusted so that coherence of UL occasion 1 is maintained.

Method 2.4-8 : Transmission power of UL occasion 2 is determined between a period in which UL occasion 1 is transmitted (eg, a period in which coherence of UL occasion 1 is maintained) and a period in which UL occasion 1 is not transmitted (eg, For example, it may be applied differently in a section in which coherence of UL occasion 1 is not maintained).

P1 may be applied to an instance of UL occasion 2 belonging to the transmission period of UL occasion 1. P2 may be applied in the remaining instance(s) of UL occasion 2 that do not belong to the transmission period of UL occasion 1 .

11 is a conceptual diagram illustrating a first embodiment in which a coherence window is applied based on UL occasion 1 in a transmission procedure of two or more UL occasions, and FIG. 12 is a coherence window in a transmission procedure of two or more UL occasions. It is a conceptual diagram illustrating a second embodiment in which is applied based on UL occasion 1.

11 and 12 , it may be indicated that P2 is allocated to an instance belonging to UL occasion 2 . According to method 2.4-8, the power that the UE actually allocates to the instance may be P1 or P2. Method 2.4-8 may be applied to the coherence window of UL occasion 1 instead of the transmission period of UL occasion 1.

To maintain coherence for UL occasion 1, the base station may indicate using RRC signaling and/or a scheduling grant (eg, a dynamic grant or a configured grant). If method 2.4-8 is applied, the UE may start transmission of UL occasion 2, and UL occasion 2 may be transmitted in the coherence window of UL occasion 1. The above-described operation may be illustrated in FIG. 11 . By adjusting the transmission power of UL occasion 2 from P2 to P1, transmission belonging to the coherence window of UL occasion 1 may be performed. After that, the UE may transmit the UL instance so that coherence of UL occasion 2 is maintained.

Meanwhile, the terminal may maintain coherence even when P1 and P2 are different from each other. In this case, although the power of UL occasion 2 is allocated to P2 in the embodiment shown in FIG. 11 , the coherence window of UL occasion 1 may be applied.

If the maintenance period of coherence (eg, coherence window) is longer than the transmission time of the UL occasion, the coherence of the UL occasion may be maintained, and in exceptional circumstances (eg, the above-described slot pattern, A slot pattern to be described later, whether to transmit another UL occasion, etc.) may be additionally considered. On the other hand, when the coherence window (W) is shorter than the transmission time (T) of the UL occasion, the UE may repeatedly apply the coherence window. T may be shortened by applying a coherence window to the remaining UL occasion(s) after placement of W (eg, an integer multiple of W). For example, T may be less than or equal to W. The terminal may be applied in a form in which the length of the coherence window is gradually shortened.

Method 2.4-9 : If the coherence window is shorter than the transmission time of the UL occasion, the coherence window having the maximum length may be repeatedly applied, and the last coherence window may have a short length.

Generalizing the above-described operation, the coherence window may be applied such that sufficient coherence is enlarged for a UL occasion scheduled first among UL occasions.

Method 2.4-10: For UL occasions having the same priority, the UL occasion (eg, UL occasion 1) in the time domain may be started first, and the remaining UL occasion(s) are UL occasions 1 can be followed.

For example, in the embodiment shown in FIG. 12 , it may be assumed that the terminal has the ability to maintain coherence in two slots. In this case, the coherence window may be derived (or set) with a time (or symbol) corresponding to two slots or two or less slots. When the UE needs to transmit UL occasion 1 during 4 slots, the UE may apply a coherence window every 2 slots. Here, a coherence window that has priority over UL occasion 1 may be applied.

In the embodiment shown in FIG. 12 , UL occasion 2 may be transmitted twice, and UL occasion 2 may completely belong to the coherence window in which UL occasion 1 is transmitted. Alternatively, UL occasion 2 may not completely belong to the coherence window in which UL occasion 1 is transmitted. UL occasion 2 may be divided into an instance belonging to the coherence window and an instance not belonging to the coherence window.

The transmission start time of UL occasion 2 may be after the transmission start time of UL occasion 1, and the coherence window for UL occasion 2 may not be newly applied. Alternatively, the coherence window for UL occasion 2 may be applied after transmission of UL occasion 1 is terminated.

Conversely, the terminal may also apply the coherence maintenance period in a form that becomes longer and longer. When UL occasion 2 is allocated, the UE may start a new coherence maintenance period for UL occasion 2 so that the coherence of UL occasion 2 is maintained. Based on this operation, it may be interpreted that important UCI and/or data are transmitted in the last UL occasion allocated by the scheduling of the base station.

Method 2.4-11: For UL occasions with the same priority, a UL occasion (eg, UL occasion 2) in time domain may be started later, and the remaining UL occasion(s) are UL occasions 2 can be followed.

13 is a conceptual diagram illustrating a third embodiment in which a coherence window is applied based on UL occasion 1 in a transmission procedure of two or more UL occasions.

Referring to FIG. 13 , the coherence window of UL occasion 1 may be interpreted as divided. UL occasion 1 may include 4 instances, and UL occasion 2 may be transmitted later in the time domain.

So that the coherence window for UL occasion 2 has priority, the coherence window for UL occasion 1 is "coherence window to which the first instance belongs" and "coherence window to which third and fourth instances belong" can be divided into

2.5 How to improve in the frequency domain

In the case of "indicated to perform K-th repeated transmission and not to perform frequency hopping", the frequency resource in the time window in which the PUSCH occasion is transmitted may maintain the same set of physical resource block (PRB). have. Alternatively, when it is indicated to perform frequency hopping, the frequency resource may have two or more PRB sets. The PRB set may mean frequency domain resource assignment (FDRA) or RB assignment indicated (or configured) by DCI and/or RRC signaling for allocating PUSCH occasions.

In order to perform frequency hopping, the base station may transmit information (eg, configuration information) indicating activation or deactivation of frequency hopping to the terminal using RRC signaling. When frequency hopping is activated, whether to perform frequency hopping may be indicated by DCI and/or RRC signaling for allocating PUSCH occasions.

When frequency hopping for PUSCH occasion transmission is performed, the base station receiving the PUSCH occasion may obtain a frequency multiplexing gain. The frequency hopping method may be divided into a frequency hopping method within a slot (hereinafter, referred to as a “first frequency hopping method”) and a frequency hopping method at a slot boundary (hereinafter referred to as a “second frequency hopping method”).

When the first frequency hopping scheme is used, frequency hopping for a PUSCH instance may be performed, and the above-described PUSCH instance may be repeated. A frequency hop of each PUSCH instance may consist of half the symbols constituting the corresponding PUSCH instance (or "a maximum integer not greater than half a symbol" or "a minimum integer not less than half a symbol").

When the second frequency hopping scheme is used, frequency hopping for a PUSCH instance may not be performed, and frequency hopping may be performed at a boundary between PUSCH instances.

In order to perform joint channel estimation in a base station receiving a PUSCH occasion, phase coherence and/or power coherence for PUSCH instances may be maintained. To support this operation, a new frequency hopping scheme may be needed. When the K-th PUSCH repeated transmission is indicated, frequency hopping is not performed in as many PUSCH instances as possible, so that the base station may perform joint channel estimation. By performing frequency hopping, the base station can obtain a frequency multiplexing gain.

Method 2.5-1 : The first K/2 (or "maximum integer not greater than K/2" or "minimum integer not less than K/2") PUSCH instances may constitute the first frequency hop, and the remaining A PUSCH instance may configure a second frequency hop.

As the index of the slot to which the first PUSCH instance belongs is an odd number or an even number, the first frequency hop may be determined as a starting PRB derived from the FDRA of the PUSCH or a PRB to which a hopping offset is applied. The second frequency hop may be determined as a start PRB not used by the first frequency hop or a PRB to which a hopping offset is applied. For convenience of explanation, the drawings to be described later show that the first frequency hop is determined by the start PRB, but the first frequency hop may be determined as the PRB to which a hopping offset is additionally applied.

The “maximum number of PUSCH instances”, “maximum length of time window”, or “maximum number of symbols” capable of maintaining power coherence and/or phase coherence may be determined according to UE capabilities. In this case, method 2.5-1 can be improved. For example, the predefined number in method 2.5-1 may be replaced with K/2. The following embodiments will be described based on K/2, but in the embodiments below, a predefined number may be used instead of K/2.

Method 2.5-2 : A predefined number may be determined (or indicated, configured) by the UE capability or RRC signaling, and the UE may derive the number of PUSCH instances belonging to the same frequency hop based on the predefined number. can

In a communication system supporting frequency division duplex (FDD), the PUSCH occasion may be transmitted in consecutive slots. When the PUSCH occasion is repeatedly transmitted K times, the PUSCH occasion may be transmitted in K consecutive slots. In a communication system supporting TDD, PUSCH occasions may be transmitted in non-contiguous slots according to a slot pattern. Examples of interpretation of a time window in which a PUSCH occasion may be transmitted and transmission of a PUSCH instance may be illustrated in FIGS. 6 , 7 , and/or 8 . If some symbols are invalid, PUSCH instances may not be transmitted in consecutive time resources. The reason is that invalid symbols (eg, DL symbols, FL symbols, SS/PBCH blocks, Type0-PDCCH CSS set, invalid symbol patterns) are located between PUSCH instances.

In this case, the terminal may not be able to maintain phase coherence and power coherence. Therefore, in order to apply Method 2.5-1 to TDD, improvement of Method 2.5-1 may be necessary.

Method 2.5-3 : Frequency hopping may be performed at a boundary between an invalid symbol and a valid symbol belonging to a PUSCH occasion.

If there is no invalid symbol, frequency hopping may not be performed in the PUSCH occasion. To solve this problem, the maximum number of adjacent PUSCH instances belonging to the same frequency hop may be limited.

Method 2.5-4 : In method 2.5-3, the number of adjacent PUSCH instances belonging to the same frequency hop may not be greater than a predefined number.

The predefined number may be determined in the PUSCH occasion allocation procedure. For example, the predefined number may be set to K/2 (or "a minimum integer not less than K/2" or "a maximum integer not greater than K/2").

When a PUSCH occasion is transmitted according to the above-described method (eg, PUSCH repetition type A/B/C/D/BB), the number of PUSCH instances that cannot be transmitted due to invalid symbols may be omitted. Alternatively, the number of PUSCH instances may be guaranteed to K.

2.5.1 Example

14A is a conceptual diagram illustrating a first embodiment of a method for applying frequency hopping to a PUSCH occasion, and FIG. 14B is a conceptual diagram illustrating a second embodiment of a method for applying frequency hopping to a PUSCH occasion.

14A and 14B , “K=8” may be indicated in the PUSCH occasion. The UE may maintain phase coherence and/or power coherence in 4 (=K/2) consecutive PUSCH instances (Method 2.5-1). Alternatively, the base station may indicate (or set) 4 to the terminal through RRC signaling. In this case, the UE may maintain phase coherence and/or power coherence for a time corresponding to four PUSCH instances (Method 2.5-2). Alternatively, the UE may maintain phase coherence and/or power coherence for a time corresponding to 4 or less PUSCH instances according to capability (Method 2.5-2).

A PUSCH occasion may consist of only valid symbols. In the embodiment shown in FIG. 14A , the frequency hop to which the first PUSCH instance belongs may be the first hop, and the first PUSCH instance may be transmitted at a frequency hop determined as the starting PRB. In the embodiment shown in FIG. 14(b) , the frequency hop to which the first PUSCH instance belongs may be the second hop, and the first PUSCH instance may be transmitted at a frequency hop determined by the start PRB and the hopping offset.

When the PUSCH instance is not dropped due to an invalid symbol, method 2.5-1 or method 2.5-2 may be applied. In this case, four PUSCH instances may belong to the same frequency hop. Frequency hopping may be performed at the boundary between PUSCH instance 4 and PUSCH instance 5.

When some PUSCH instances are dropped or deferred, method 2.5-3 and/or method 2.5-4 may be applied. In FIGS. 15 and 16, which will be described later, PUSCH instances 2 and 3 may be dropped or postponed due to invalid symbols. In FIGS. 17 and 18, which will be described later, PUSCH instances 2, 3, and 5 may be dropped or postponed due to invalid symbols.

15A is a conceptual diagram illustrating a first embodiment of a method of applying frequency hopping to a PUSCH occasion in consideration of invalid symbols in a PUSCH occasion from which a PUSCH instance is dropped, and FIG. 15B is a PUSCH occasion from which a PUSCH instance is dropped. It is a conceptual diagram illustrating a second embodiment of a method of applying frequency hopping to a PUSCH occasion in consideration of invalid symbols.

Referring to FIG. 15A , method 2.5-3 may be applied. PUSCH instances 2 and 3 may be dropped, and the remaining PUSCH instance(s) may belong to different frequency hops. Frequency hopping may be performed at the boundary between an invalid symbol and a valid symbol. PUSCH instances 4, 5, 6, 7, and 8 may belong to the same frequency hop. The UE may maintain phase coherence and/or power coherence in PUSCH instances 4, 5, 6, 7, and 8.

Referring to FIG. 15B , method 2.5-4 may be applied, and frequency hopping may be performed at a boundary between an invalid symbol and a valid symbol. In this case, the number of consecutive PUSCH instances may be limited to four. The UE may maintain phase coherence and/or power coherence in PUSCH instances 4, 5, 6, and 7.

16A is a conceptual diagram illustrating a first embodiment of a method of applying frequency hopping to a PUSCH occasion in consideration of invalid symbols in a PUSCH occasion in which a PUSCH instance is postponed, and FIG. 16B is a PUSCH occasion in which a PUSCH instance is postponed. It is a conceptual diagram illustrating a second embodiment of a method of applying frequency hopping to a PUSCH occasion in consideration of invalid symbols, and FIG. 16C shows frequency hopping to a PUSCH occasion in consideration of invalid symbols in a PUSCH occasion in which a PUSCH instance is postponed. It is a conceptual diagram showing a third embodiment of the method to be applied.

Referring to FIG. 16A , the boundary of frequency hopping may be determined based on the maximum number of PUSCH instances. Two PUSCH instances may be deferred. Even when four PUSCH instances are discontinuously arranged, the four PUSCH instances may belong to the same frequency hop. In this case, the UE may maintain phase coherence and/or power coherence of consecutive PUSCH instances in the time domain among PUSCH instances belonging to the same frequency hop. Here, consecutive PUSCH instances may be “PUSCH instances 2, 3, and 4” or “PUSCH instances 5, 6, 7, and 8”.

Referring to FIG. 16B , frequency hopping may be performed at a boundary between an invalid symbol and a valid symbol, and method 2.5-3 may be applied. In this case, two PUSCH instances may be deferred, and the remaining PUSCH instances may belong to different frequency hops based on the deferred PUSCH instance. The UE may maintain phase coherence and/or power coherence in PUSCH instances 4, 5, 6, 7, and 8.

Referring to FIG. 16C , frequency hopping may be performed at a boundary between an invalid symbol and a valid symbol, and the maximum number of consecutive PUSCH instances may be indicated. Method 2.5-4 may be applied, and 4 or less PUSCH instances may belong to the same frequency hop. The UE may maintain phase coherence and/or power coherence in PUSCH instances 2, 3, 4, and 5. The UE may maintain phase coherence and/or power coherence in PUSCH instances 6, 7, and 8.

17 is a conceptual diagram illustrating a third embodiment of a method of applying frequency hopping to a PUSCH occasion in consideration of invalid symbols in a PUSCH occasion from which a PUSCH instance is dropped.

Referring to FIG. 17 , method 2.5-3 may be applied. PUSCH instances 2, 3, and 5 may be dropped, and the remaining PUSCH instances may belong to different frequency hops. PUSCH instances 6, 7, and 8 may belong to the same frequency hop. The UE may maintain phase coherence and/or power coherence in PUSCH instances 6, 7, and 8.

Alternatively, method 2.5-4 may be applied in the embodiment shown in FIG. 17 . In this case, the number of consecutive PUSCH instances may be three. That is, the number of consecutive PUSCH instances may be smaller than the maximum number. Frequency hopping when method 2.5-4 is applied may be the same as frequency hopping when method 2.5-3 is applied.

18A is a conceptual diagram illustrating a fourth embodiment of a method of applying frequency hopping to a PUSCH occasion in consideration of invalid symbols in a PUSCH occasion in which a PUSCH instance is postponed, and FIG. 18B is a PUSCH occasion in which a PUSCH instance is postponed. It is a conceptual diagram illustrating a fifth embodiment of a method of applying frequency hopping to a PUSCH occasion in consideration of invalid symbols, and FIG. 18C is a diagram illustrating frequency hopping to a PUSCH occasion in consideration of invalid symbols in a PUSCH occasion in which a PUSCH instance is postponed. It is a conceptual diagram showing a sixth embodiment of a method to be applied.

Referring to FIG. 18A , the boundary of frequency hopping may be determined based on the maximum number of PUSCH instances. 3 PUSCH instances may be deferred, and 4 PUSCH instances may be arranged discontinuously. Four non-contiguous PUSCH instances may belong to the same frequency hop. In this case, the UE may maintain phase coherence and/or power coherence of consecutive PUSCH instances in the time domain among PUSCH instances belonging to the same frequency hop. Here, the consecutive PUSCH instances may be “PUSCH instances 3 and 4” or “PUSCH instances 5, 6, 7, and 8”.

Referring to FIG. 18B , frequency hopping may be performed at a boundary between an invalid symbol and a valid symbol, and method 2.5-3 may be applied. In this case, three PUSCH instances may be deferred, and the remaining PUSCH instances may belong to different frequency hops based on the deferred PUSCH instance. The UE may maintain phase coherence and/or power coherence in PUSCH instances 3, 4, 5, 6, 7, and 8.

Referring to FIG. 18C , frequency hopping may be performed at a boundary between an invalid symbol and a valid symbol, and the maximum number of consecutive PUSCH instances may be indicated. Method 2.5-4 may be applied, and 4 or less PUSCH instances may belong to the same frequency hop. The UE may maintain phase coherence and/or power coherence in PUSCH instances 3, 4, 5, and 6. The UE may maintain phase coherence and/or power coherence in PUSCH instances 7 and 8.

2.6 Sub-PRB-based transmission method

In order to extend the UL coverage, the UE may use high transmit power. When the transmission power of the terminal increases, the interference that the terminal exerts on other base stations may increase. The UE may use the same transmission power and a narrow bandwidth (eg, a small number of PRBs). In this case, since the energy per RE (EPRE) is high, the block error rate (BLER) in the base station may be reduced. Even when one or more PRBs are used, PUSCH may not be transmitted on all subcarriers, and PUSCH may be allocated on some subcarriers. PUSCH may not be allocated in the remaining subcarrier(s). The UE may increase the EPRE by allocating transmit power only to the subcarriers used. In this case, BLER in the base station may be further reduced.

When some subcarriers are used for PUSCH transmission in a plurality of PRBs, the base station may use the DM-RS in a wide band. Therefore, the base station can accurately estimate the channel using the wide-band DM-RS. The UE may increase the EPRE only on some subcarriers. In this case, BLER in the base station may be further reduced.

2.6.1 DM-RS allocation method

The PUSCH DM-RS may be configured according to two schemes. When DM-RS config 1 is used, the PUSCH DM-RS may be mapped at intervals of two subcarriers in the same symbol. When DM-RS config 2 is used, the PUSCH DM-RS may be mapped at intervals of 6 subcarriers in the same symbol. The base station may indicate DM-RS config 1 or DM-RS config 2 to the terminal by using RRC signaling. The UE may know which code division multiplexing (CDM) group is applied based on the scheduling DCI. Accordingly, the UE may determine the mapping of the PUSCH DM-RS.

Method 2.6-1 : When PUSCH is allocated per sub-PRB, the base station may indicate DM-RS config 1 or DM-RS config 2 to the terminal by using RRC signaling.

According to the DM-RS config, since the method in which the DM-RS is mapped is different, the channel may be estimated from subcarriers to which the DM-RS belonging to the allocated bandwidth is mapped. In addition, by applying the interpolation method, channels for subcarriers to which DM-RS is not mapped can be estimated.

Method 2.6-2 : When PUSCH is allocated in units of sub-PRBs, DM-RS config 1 or DM-RS config 2 defined in the technical standard may be used.

For example, only DM-RS config 1 may be used. The base station may allocate the sub-PRB-based PUSCH only when DM-RS config 1 is indicated to the terminal. In this case, the PUSCH may be allocated only to the subcarrier to which the DM-RS is mapped. In this case, it is not necessary to perform interpolation on the subcarrier to which the DM-RS is not mapped.

2.6.2 How data is allocated

Data (eg, TB, UCI, or SCI) may be mapped based on sub-PRB. In this case, in order to reduce the peak to average power rate (PAPR), it may be desirable to perform a pre-processing procedure to obtain a single carrier property. For example, if a discrete Fourier transform (DFT) preprocessing is applied together with an inverse fast Fourier transform (IFFT), a single carrier property can be obtained.

Method 2.6-3 : For subcarriers belonging to the allocated bandwidth, data may be mapped on equally spaced subcarriers, and data may not be mapped on the remaining subcarriers.

For example, with respect to transmission to which transform precoding is applied, subcarriers to which data are mapped may not be consecutively arranged. That is, subcarriers to which data is mapped may always be arranged at equal intervals. The application of method 2.6-3 can be extended. For example, when the TB size is large, a small number of subcarriers may be adjacent, and adjacent subcarriers may be arranged at equal intervals. That is, with respect to subcarriers belonging to the allocated bandwidth, two or more subcarriers may be adjacent, adjacent subcarriers may be disposed at equal intervals, data may be mapped to corresponding subcarriers, and data from the remaining subcarriers may be mapped it may not be In this case, even when transform precoding is applied, multi-carrier characteristics can be obtained. Therefore, the method(s) below may be applied.

Method 2.6-4 : For subcarriers belonging to the allocated bandwidth, data may be mapped only on consecutive subcarriers in the PRB, and data may not be mapped to the remaining subcarriers.

For example, the UE may apply method 2.6-3 or method 2.6-4 according to the waveform for transmitting the PUSCH.

Meanwhile, a subcarrier to which data is mapped and a subcarrier to which a DM-RS is mapped may be allocated in the same PRB. DM-RS and data may be indicated independently of each other. Alternatively, DM-RS and data may be indicated to have the same value (eg, the same subcarrier). In this case, the performance of channel estimation can be improved.

Method 2.6-5 : When the CDM group of the DM-RS is indicated, this can be applied to the data mapping operation as well.

The UE may map data only to subcarriers to which the CDM group of the DM-RS is mapped. Therefore, according to method 2.6-5, the base station may estimate the channel based on the received DM-RS, and then may not apply interpolation to estimate the channel for the subcarrier to which the data is mapped. However, if data is mapped only to a subcarrier to which the CDM group of the DM-RS is indicated, scheduling restrictions may be large. Therefore, a method not limited to the above-described mapping method may be applied.

Method 2.6-6 : Scheduling DCI (or scheduling RRC signaling message) may indicate subcarriers to which data is mapped, and subcarriers associated with the CDM group of DM-RS may be indicated differently from subcarriers to which data is mapped.

The scheduling DCI (or the scheduling RRC signaling message) may indicate subcarrier sets of data. The subcarrier set(s) may be arranged at equal intervals. A small number of subcarriers belonging to the subcarrier set(s) may be concatenated, and the contiguous subcarriers may be arranged at equal intervals. When subcarriers (e.g., contiguous subcarriers) are arranged at equal intervals, the base station instructs (e.g., sets) the offset of the subcarrier (e.g., only the offset of the subcarrier) to the terminal. If "subcarriers are consecutively arranged and n consecutive subcarriers are again arranged at equal intervals", the base station may indicate (eg, set) an index for the subcarrier set to the terminal. Here, n may be a natural number.

Meanwhile, in order to support PUSCH transmission based on sub-PRB, the base station may allocate TBs of different sizes. When the number of subcarriers occupied by the sub-PRB is reflected, the TB size may be reduced. For example, when the UE transmits the PUSCH using half of the subcarriers, the value of the scaling factor may be 1/2, and the scaling factor may be reflected in the equation for deriving the TB size.

2.6.3 Example

A frequency hopping pattern may be applied within the PRB.

2.6.4 Example

Embodiments of a sub-PRB based PUSCH (sub-PRB based PUSCH) indicated to the UE will be shown in FIGS. 19, 20, and 21 below. 19, 20, and 21 may illustrate a method in which data is mapped to a subcarrier in a PUSCH to which one or more PRBs are allocated. Here, the DM-RS (eg, DM-RS config 1, DM-RS config 2, or CDM group) may be allocated regardless of data, and it may be indicated that data and DM-RS are mapped to the same subcarrier. can

19A is a conceptual diagram illustrating a first embodiment of an IFDMA (Interleaved Frequency Division Multiplex Access) mapping method for a sub-PRB-based PUSCH, and FIG. 19B is a second embodiment of an IFDMA mapping method for a sub-PRB-based PUSCH. It is a conceptual diagram showing an example.

Referring to FIG. 19A , half of the subcarriers may be used in the allocated band, and the subcarrier shift may be zero.

Referring to FIG. 19B , half of the subcarriers may be used in the allocated band, and the subcarrier shift may be 1. The value of the subcarrier shift in the embodiment shown in FIG. 19A may be different from the value of the subcarrier shift in the embodiment shown in FIG. 19B . The subcarrier shift may be indicated to the UE by scheduling DCI and/or RRC signaling.

20A is a conceptual diagram illustrating a first embodiment of a hybrid method of IFDMA mapping and localized mapping for sub-PRB-based PUSCH, and FIG. 20B is IFDMA mapping and localized mapping for sub-PRB-based PUSCH It is a conceptual diagram illustrating a second embodiment of a hybrid method, and FIG. 20C is a conceptual diagram illustrating a third embodiment of a hybrid method of IFDMA mapping and localized mapping for sub-PRB-based PUSCH.

20A, 20B, and 20C , some subcarriers may be utilized in an allocated band, and two consecutive subcarriers may be arranged at regular intervals. In the embodiment shown in FIG. 20A, the subcarrier shift may be 0, in the embodiment shown in FIG. 20B, the subcarrier shift may be 1, and in the embodiment shown in FIG. 20C, the subcarrier shift may be 2. That is, in embodiments, different subcarrier shifts may be set. The subcarrier shift may be indicated to the UE by scheduling DCI and/or RRC signaling.

21A is a conceptual diagram illustrating a first embodiment of a localized mapping method for a sub-PRB-based PUSCH, and FIG. 21B is a conceptual diagram illustrating a second embodiment of a localized mapping method for a sub-PRB-based PUSCH.

21A and 21B , some subcarriers may be utilized in an allocated band. For example, six consecutive subcarriers may be utilized. In the embodiment shown in FIG. 21A, the subcarrier shift may be 0, and in the embodiment shown in FIG. 21B, the subcarrier shift may be 1. That is, in embodiments, different subcarrier shifts may be set. The subcarrier shift may be indicated to the UE by scheduling DCI and/or RRC signaling.

Chapter 3 How to extend the reach of PUCCH

A UE located in the boundary region of a cell may transmit PUCCH (eg, PUCCH format 1, 2, 3, or 4). In this case, the base station may estimate the UL channel based on the received DM-RS, and may demodulate the PUCCH based on the estimation result of the UL channel. The base station may identify PUCCH format 1 based on a spreading code. The base station may identify PUCCH format 2, 3, or 4 based on a Reed Muller code or a polar code. In this case, the performance obtained by the base station may be defined as BLER, ACK-to-NACK probability, NACK-to-ACK probability, and/or DTX-to-ACK probability.

A UE located in the boundary region of a cell may transmit a PUCCH. In this case, the performance in the base station may be greatly affected by the estimation performance of the UL channel using the DM-RS. If the estimation error of the UL channel is large, the base station may not detect the UCI. Therefore, when the PUCCH is repeatedly transmitted, a method for the base station to utilize all of the PUCCH DM-RSs has been discussed in Chapter 2. The application method of PUSCH DM-RS can be easily extended, and the extended method can also be applied to PUCCH DM-RS.

As another method, when PUCCH format 0 is used, a method in which spread UCI configures UCCH without a separate DM-RS may be considered. In this case, the base station does not need to estimate the UL channel. Accordingly, the base station can detect the UCI using the spreading code without estimating the UL channel. This method may be extended, and a new PUCCH format without DM-RS may be considered based on the extended method.

3.1 DM-RS-less PUCCH

DM-RS-less PUCCH may be used when the UCI size is smaller than a preset size. A UCI size (eg, a preset size) for applying the DM-RS-less PUCCH may be defined in a technical standard. Alternatively, the base station may inform the terminal of the UCI size for applying the DM-RS-less PUCCH by using RRC signaling. For example, the preset size may be 3 bits, 11 bits, or 16 bits or less.

When the UCI size is 3 bits or more, the terminal may generate a codeword by performing an encoding operation on an information word (eg, information bit) of the UCI, and modulate the codeword by performing a modulation operation on the codeword. A symbol (eg, a QPSK symbol) may be generated, and the modulation symbol may be mapped to an RE.

According to the number of REs of the DM-RS-less PUCCH, the effective code rate for the codeword may be determined. For example, the information word may be k bits, and the code word may be n bits. Each of k and n may be a natural number. The base station may inform the terminal of the number of REs (eg, N) of the DM-RS-less PUCCH. N may be a natural number. If the number of REs of the DM-RS-less PUCCH is N, N QPSK symbols may be required, and code blocks may be represented by 2N bits.

When the number of code blocks is M, each of the M code blocks (eg, one codeword) may be expressed by 2N/M bits. To support this operation, cyclic extension may be applied. When the information word is k bits, the mapping relationship between the index corresponding to the k bits and the information word may be one to one. Each of the indices may correspond to a respective spreading code. Accordingly, one index may correspond to one RE mapping. The spreading code may be a set of QPSK sequences (eg, one-dimensional sequences) defined for each symbol. Alternatively, the spreading code may be a set of QPSK sequences mapped to a 2D resource grid defined in time and frequency.

22 is a conceptual diagram illustrating a first embodiment of a frequency-first RE mapping method.

Referring to FIG. 22 , a PUCCH (eg, a PUCCH resource) may be composed of T symbols and B subcarriers. That is, the PUCCH may be mapped to B×T REs. The frequency hopping operation may be configured by higher layer signaling. Alternatively, the embodiment shown in FIG. 22 may be regarded as RE mapping in a logical domain.

The base station may indicate (eg, configure) one PUCCH resource to the terminal. The UE may know that B×T REs are used for PUCCH transmission. The terminal may convert an information word (eg, a k-bit information word) into a codeword (eg, an n-bit codeword) by using the linear code defined in the technical standard. In this case, the nominal code rate may be k/n. In order to utilize all the PUCCH resources, the UE may map code blocks of 2×B×T bits. The codeword is c ₀ , c ₁ , … , c _n-1 , the extended codeword is c ₀ , c ₁ , ... , c _n-1 , c ₀ , c ₁ , … can be expressed as When there are M code blocks, the codeword may be extended to 2×B×T/M bits. Each code block may be modulated, and the modulated code blocks may be mapped to the resource grid in the order of the code blocks.

The bandwidth of the DM-RS-less PUCCH may be a specific combination. For example, a particular combination may be a number of PRBs that are multiples of 2, 3, or 5. The value of B in FIG. 22 may be a value obtained by converting a bandwidth into the number of subcarriers.

The number of symbols of the DM-RS-less PUCCH may be limited to one or two. Alternatively, the number of symbols of the DM-RS-less PUCCH may be limited to 4 or more. Alternatively, there may be no restriction on the number of symbols of the DM-RS-less PUCCH. The number of symbols in the PUCCH may be derived from the PUCCH resource index.

3.1.1 How to reflect slot format

DM-RS-less PUCCH may be transmitted in a communication system supporting TDD. According to the amount of traffic in a communication system supporting TDD, the slot format may be indicated by a ratio of DL traffic and UL traffic. The slot format may be divided into a semi-static slot format and a dynamic slot format. The base station may indicate to the terminal a slot pattern having a preset period using RRC signaling. In this case, the slot may be divided into a DL slot, a UL slot, and a special slot. A specific slot may be composed of a DL symbol, a FL symbol, and a UL symbol. When the FL symbol is indicated by RRC signaling, the UE receiving the DCI format 2_0 may check information (eg, SFI) indicating the FL symbol as a DL symbol, FL symbol, or UL symbol.

Method 3.1-1 : DM-RS-less PUCCH may be transmitted in all indicated time resources or some time resources.

According to the slot format, the UE may transmit the PUCCH not only in the UL symbol but also in the FL symbol. For example, the DM-RS-less PUCCH may include HARQ-ACK for the PDSCH allocated by DL-DCI. In this case, the UE may transmit the PUCCH even in the FL symbol.

23A is a conceptual diagram illustrating a first embodiment of a symbol mapping method for SFI, and FIG. 23B is a conceptual diagram illustrating a second embodiment of a symbol mapping method for SFI.

Referring to FIG. 23A , PUCCH may be transmitted in FL symbols and UL symbols. A PUCCH consisting of 4 symbols may be transmitted.

Referring to FIG. 23B , the UE may transmit the PUCCH only in the UL symbol. For example, the DM-RS-less PUCCH may include HARQ-ACK for the PDSCH allocated by RRC signaling (or PDSCH activated by DCI). In this case, the UE may transmit the PUCCH only in the UL symbol. DM-RS-less PUCCH may be transmitted only in valid symbols (eg, UL symbols). That is, the PUCCH may be transmitted only in UL symbols. Only two symbols may be transmitted among the PUCCHs composed of four symbols.

When the PUCCH is transmitted only in some symbols, the code block(s) of the UCI may be mapped regardless of the slot format. Alternatively, code block(s) of UCI may be mapped according to a slot format. The difference between Method 3.1-2 and Method 3.1-3 below may be whether a slot format is applied in a mapping procedure of code block(s) of UCI.

Method 3.1-2 : When method 3.1-1 is applied, code block(s) of UCI may be mapped regardless of a slot format, and PUCCH may be transmitted only in valid symbols.

The UE may perform a symbol-based puncturing operation in order to transmit a PUCCH (eg, DM-RS-less PUCCH) only in a valid symbol (eg, a UL symbol). Since the PUCCH transmission is performed regardless of the slot format, the implementation in the terminal can be simplified.

Method 3.1-3 : Code block(s) of UCI, to which method 3.1-1 is applied, may be mapped only to valid symbols according to the slot format. PUCCH can be transmitted only in valid symbols.

The UE may follow the slot format indicated by RRC signaling and/or DCI format 2_0. In this case, the UE may not be able to transmit PUCCH in some symbols. Some symbols may be excluded from the mapping of code block(s) of UCI. The UE may perform a rate matching operation of mapping the UCI code block(s) only in valid symbols. The UE may first reflect RRC signaling and/or DCI indicating the slot format, and then map the code block(s) of UCI.

According to the proposed method, some symbols may be transmitted in the PUCCH, but transmission power may be determined based on the assumption that all symbols constituting the PUCCH are transmitted.

3.1.2 Repeat transmission method

When the terminal is located in the boundary region of the cell, the base station may allocate the maximum power to the PUCCH and may apply the minimum code rate to the PUCCH. In order to lower the error rate of the PUCCH, the base station may instruct the terminal to repeatedly transmit the PUCCH.

The repeated transmission of PUCCH may be indicated to the UE by "RRC signaling" or "combination of RRC signaling and DCI". Therefore, the UE may repeatedly transmit the PUCCH. The PUCCH may be repeatedly transmitted using time resources and frequency resources in a slot or subslot. Repeated transmission of PUCCH may mean "transmitting PUCCH using the same PUCCH resource in two consecutive slots or two consecutive sub-slots". The number of repetitions of PUCCH may be indicated to the UE by “RRC signaling” or “combination of RRC signaling and DCI”. For convenience of description, when PUCCH is repeatedly transmitted, all PUCCHs may be referred to as PUCCH occasions, and each PUCCH may be referred to as a PUCCH instance.

When the slot format is configured in the terminal, the number of transmissions of the PUCCH instance may be reduced. Alternatively, the number of transmissions of the PUCCH instance may be guaranteed. For example, in a system supporting FDD, according to the slot format indicated to the UE, the PUCCH instance may not be transmitted in any slot (or subslot). Even in this case, the PUCCH instance may be regarded as transmitted. That is, the actual number of transmissions of the PUCCH instance may be reduced. For another example, in a communication system supporting TDD, according to the slot format indicated to the terminal, the PUCCH instance may not be transmitted in any slot (or sub-slot). In this case, the corresponding PUCCH instance may be transmitted in the next slot (eg, sub-slot). That is, the number of transmissions of the PUCCH instance may be guaranteed.

24A is a conceptual diagram illustrating a first embodiment of a RE mapping method for SFI when PUCCH is repeatedly transmitted, and FIG. 24B shows a second embodiment of a RE mapping method for SFI when PUCCH is repeatedly transmitted. It is a conceptual diagram, and FIG. 24C is a conceptual diagram illustrating a third embodiment of a RE mapping method related to SFI when PUCCH is repeatedly transmitted.

24A, 24B, and 24C , the UE may transmit a PUCCH occasion. According to the slot format, the transmission method of the PUCCH instance may be classified in detail. In the embodiment shown in FIG. 24A , when a PUCCH instance is transmitted in all symbols (eg, all symbols in consecutive slots (or subslots)) according to the slot format, the UE uses 4 slots (eg For example, 4 subslots) may be used to transmit the PUCCH instance 4 times.

On the other hand, when the PUCCH instance is transmitted in some symbols according to the slot format, the method shown in FIG. 24B may be used.

In the embodiment shown in FIG. 24B , a PUCCH instance may be transmitted only in valid symbols. In order to transmit the PUCCH instance 4 times, 4 consecutive slots (eg, sub-slots) may be considered. Some symbols among symbols belonging to the PUCCH instance may not be valid. That is, some symbols may be invalid symbols. In this case, the invalid symbol may not be used for transmission. If all symbols in the PUCCH instance are not valid, the corresponding PUCCH instance may not be transmitted.

In the embodiment shown in FIG. 24C , the number of transmissions of the PUCCH instance may be guaranteed. In order to transmit the PUCCH instance 4 times, 5 slots (eg, sub-slots) may be used. A PUCCH occasion (eg, PUCCH instance) may be transmitted in 4 non-contiguous slots (eg, sub-slots). A PUCCH instance may be transmitted using all symbols.

A method of mapping the code block(s) of UCI to a PUCCH instance may be applied to each PUCCH instance. Alternatively, a method of mapping code block(s) of UCI to a PUCCH instance may be applied in a PUCCH occasion.

Method 3.1-4 : Code block(s) of UCI may be mapped identically for each PUCCH instance.

PUCCH instances may always be mapped identically. _{For example, when the PUCCH instance consists of L sign bits, c 0} , c ₁ , ... which are code block(s) of UCI for the first PUCCH instance in the embodiments shown in FIGS. 24B and 24C . , c _L-1 may be mapped according to a predefined order, and a modulation operation may be performed on the code block(s). The above-described mapping operation and modulation operation may be equally applied to the second PUCCH instance, the third PUCCH instance, and the fourth PUCCH instance. Then, in the embodiment shown in Fig. 24B, the slot format may be considered. Invalid symbols in the PUCCH instance may be punctured. That is, the invalid symbol may not be transmitted. According to the proposed method 3.1-4, the UE can generate all PUCCH instances identically. Therefore, implementation in the terminal may be easy.

Method 3.1-5 : Code block(s) of UCI may be mapped in PUCCH occasions. Accordingly, code blocks of consecutive UCIs in adjacent PUCCH instances may be mapped.

PUCCH instances may be concatenated, and code block(s) of UCI may be mapped in units of PUCCH occasions. In the embodiment shown in FIG. 24B, a PUCCH instance may be transmitted only in some symbols according to a slot format. In this case, the transmission symbols may be considered to be consecutively arranged. The code block(s) of UCI c ₀ , c ₁ , ... , c _L-1 , c ₀ , c ₁ , … may be mapped according to a preset order, and a modulation operation may be performed on the code block(s). The above-described method may also be applied to symbols belonging to other PUCCH instances. The above-described method can be easily applied to the embodiment shown in Fig. 24C.

3.2 How to improve in the frequency domain

Repeated transmission of the PUSCH (eg, PUSCH occasion) K times may be indicated. In this case, if it is indicated that frequency hopping is not performed, frequency resources in the time window in which the PUCCH occasion is transmitted may maintain the same PRB set. Alternatively, if frequency hopping is indicated to be performed, a frequency resource in a time window in which a PUCCH occasion is transmitted may include two or more PRB sets. PRB set means "RB assignment indicated by DCI for allocating PUCCH occasions" or "RB allocation derived from PRI and / or CCE indexes indicated (or set) by RRC signaling". have.

In order to perform frequency hopping, the terminal may receive an RRC signaling message including information indicating activation or deactivation of frequency hopping from the base station. If frequency hopping is activated, a DCI or RRC signaling message for allocating a PUCCH occasion may indicate whether frequency hopping is performed.

The UE may transmit a PUCCH occasion by performing frequency hopping. In this case, a frequency multiplexing gain may be obtained at the base station. The frequency hopping method may be divided into a frequency hopping method within a slot (hereinafter, referred to as a “first frequency hopping method”) and a frequency hopping method at a slot boundary (hereinafter referred to as a “second frequency hopping method”).

When the first frequency hopping scheme is used, frequency hopping for a PUCCH instance may be performed, and the corresponding PUCCH instance may be repeated. Each of the frequency hops may consist of half of the symbols constituting the PUCCH (or "the maximum integer not greater than half of a symbol" or "the minimum integer not less than half of a symbol").

When the second frequency hopping scheme is used, frequency hopping for a PUCCH instance may not be performed, and frequency hopping may be performed at a boundary between PUCCH instances.

In order for a base station receiving a PUCCH occasion to perform a joint channel estimation operation, phase coherence and/or power coherence of PUCCH instances may be maintained. To support this operation, a new frequency hopping scheme may be needed. If K times repeated transmission of a PUCCH instance is indicated, frequency hopping may not be performed in as many PUCCH instances as possible. Accordingly, the base station may perform a joint channel estimation operation. When frequency hopping is performed, a frequency multiplexing gain may be obtained at the base station.

Method 3.2-1 : The first K/2 (or "maximum integer not greater than K/2" or "minimum integer not less than K/2") PUCCH instances may constitute the first frequency hop, and the remaining PUCCH instance(s) may constitute a second frequency hop.

Here, the PRB of the first frequency hop may be determined according to the index (eg, odd or even number) of the slot to which the first PUCCH instance belongs. For example, the PRB of the first frequency hop may be determined as the starting PRB of the PUCCH or the 2nd PRB. The PRB of the second frequency hop may be determined as an unused PRB (eg, a start PBR or a 2nd PRB) in the first frequency hop.

The “maximum number of PUCCH instances”, “maximum length of time window”, and/or “maximum number of symbols” for which power coherence and/or phase coherence are maintained may be determined according to terminal capabilities. In this case, method 3.2-1 can be improved. In the improved method 3.2-1, the predefined number may replace K/2. The embodiments below will be described based on K/2, but various values (eg, a predefined number) as well as K/2 may be applied to the embodiments below.

Method 3.2-2 : The predefined number may be determined (or indicated or configured) by UE capability or RRC signaling. The number of PUCCH instances belonging to the same frequency hop can be derived.

In a communication system supporting FDD, the PUCCH occasion may be transmitted in consecutive slots. When the PUCCH occasion is repeatedly transmitted K times, the PUCCH occasion may be transmitted in K consecutive slots. In a communication system supporting TDD, a PUCCH occasion may be transmitted in non-contiguous slots according to a slot pattern. Examples of interpretation of a time window in which a PUSCH occasion may be transmitted and transmission of a PUCCH instance may be illustrated in FIG. 24 . If some symbols are invalid, PUCCH instances may not be transmitted in consecutive time resources. The reason is that invalid symbols (eg, DL symbols, FL symbols, SS/PBCH blocks, Type0-PDCCH CSS set, invalid symbol patterns) are located between PUCCH instances.

In this case, the terminal may not be able to maintain phase coherence and power coherence. Therefore, in order to apply method 3.2-1 to a communication system supporting TDD, improvement of method 3.2-1 may be required.

Method 3.2-3 : At least frequency hopping may be performed at the boundary between an invalid symbol and a valid symbol belonging to a PUCCH occasion.

If there is no invalid symbol, frequency hopping may not be performed in the PUCCH occasion. To solve this problem, the maximum number of adjacent PUCCH instances belonging to the same frequency hop may be limited.

Method 3.2-4 : In method 3.2-3, the number of adjacent PUCCH instances belonging to the same frequency hop may not be greater than a predefined number.

The predefined number may be determined in the allocation procedure of the PUCCH occasion. For example, the predetermined number may be determined as K/2 (or "a minimum integer not less than K/2" or "a maximum integer not greater than K/2").

In the transmission procedure of the PUCCH occasion, the number of PUCCH instances that cannot be transmitted due to an invalid symbol may be guaranteed to K.

3.2.1 Example

In the PUCCH occasion, K=8 may be indicated. The UE may maintain phase coherence and/or power coherence in 4 (=K/2) consecutive PUCCH instances (Method 3.2-1). The base station may indicate (or set) 4 to the terminal using RRC signaling. In this case, the UE may maintain phase coherence and/or power coherence for a time corresponding to four PUSCH instances (Method 3.2-2). The UE may maintain phase coherence and/or power coherence for a time corresponding to 4 or less PUCCH instances according to capability (Method 3.2-2).

25A is a conceptual diagram illustrating a first embodiment of a frequency hopping method for a PUCCH occasion, and FIG. 25B is a conceptual diagram illustrating a second embodiment of a frequency hopping method for a PUCCH occasion.

Referring to FIG. 25A , the PUCCH occasion may consist of only valid symbols, and the frequency hop to which the first PUCCH instance belongs may be the first hop. The first PUCCH instance may be transmitted in a frequency hop determined as the starting PRB.

Referring to FIG. 25B , a PUCCH occasion may consist of only valid symbols, and a frequency hop to which a first PUCCH instance belongs may be a second hop. The first PUCCH instance may be transmitted at a frequency hop determined based on the starting PRB and the hopping offset.

When a PUCCH instance is not dropped due to an invalid symbol, if method 3.2-1 or method 3.2-2 is applied, four PUCCH instances may belong to the same frequency hop. Frequency hopping may be performed at the boundary between PUCCH instance 4 and PUCCH instance 5.

When some PUCCH instances are deferred, methods 3.2-3 and 3.2-4 may be applied. An embodiment in which PUCCH instances 2 and 3 are deferred due to invalid symbols will be shown in FIG. 26 . An embodiment in which PUSCH instances 2, 3, and 5 are postponed due to invalid symbols will be shown in FIG. 27 .

26A is a conceptual diagram illustrating a first embodiment of a frequency hopping method of a PUCCH occasion considering an invalid symbol in a PUCCH occasion in which a PUCCH instance is postponed, and FIG. 26B is a PUCCH instance in which an invalid symbol is considered in a deferred PUCCH occasion A conceptual diagram illustrating a second embodiment of a frequency hopping method of a PUCCH occasion, and FIG. 26C is a conceptual diagram illustrating a third embodiment of a frequency hopping method of a PUCCH occasion considering invalid symbols in a PUCCH occasion in which a PUCCH instance is postponed to be.

Referring to FIG. 26A , the boundary of frequency hopping may be determined based on the maximum number of PUCCH instances. Two PUCCH instances may be deferred, and four non-contiguous PUCCH instances may belong to the same frequency hop. In this case, among PUCCH instances belonging to the same frequency hop, consecutive PUCCH instances in the time domain may maintain phase coherence and/or power coherence. Here, phase coherence and/or power coherence may be maintained in PUCCH instances 2, 3, and 4, and phase coherence and/or power coherence may be maintained in PUCCH instances 5, 6, 7, and 8 have.

Referring to FIG. 26B , frequency hopping may be performed at a boundary between an invalid symbol and a valid symbol. When method 3.2-3 is applied, two PUCCH instances may be deferred, and the remaining PUCCH instances may belong to different frequency hops based on a deferred PUCCH instance. Phase coherence and/or power coherence in PUCCH instances 4, 5, 6, 7, and 8 may be maintained.

Referring to FIG. 26C , frequency hopping may be performed at a boundary between an invalid symbol and a valid symbol, and the maximum number of consecutive PUCCH instances may be set. When method 3.2-4 is applied, 4 or less PUCCH instances may belong to the same frequency hop. The UE may maintain phase coherence and/or power coherence in PUCCH instances 2, 3, 4, and 5. In addition, the UE may maintain phase coherence and/or power coherence in PUCCH instances 6, 7, and 8.

27A is a conceptual diagram illustrating a fourth embodiment of a frequency hopping method of a PUCCH occasion considering an invalid symbol in a PUCCH occasion in which a PUCCH instance is postponed, and FIG. 27B is a PUCCH occasion in which a PUCCH instance is postponed considering an invalid symbol. A conceptual diagram illustrating a fifth embodiment of a frequency hopping method of a PUCCH occasion, and FIG. 27C is a conceptual diagram illustrating a sixth embodiment of a frequency hopping method of a PUCCH occasion considering invalid symbols in a PUCCH occasion in which a PUCCH instance is postponed to be.

Referring to FIG. 27A , the boundary of frequency hopping may be determined based on the maximum number of PUCCH instances. 3 PUCCH instances may be deferred, and 4 non-contiguous PUCCH instances may belong to the same frequency hop. In this case, phase coherence and/or power coherence for consecutive PUCCH instances in the time domain among PUCCH instances belonging to the same frequency hop may be maintained. Here, phase coherence and/or power coherence may be maintained in PUCCH instances 3 and 4, and phase coherence and/or power coherence may be maintained in PUCCH instances 5, 6, 7, and 8.

Referring to FIG. 27B , frequency hopping may be performed at a boundary between an invalid symbol and a valid symbol. When method 3.2-3 is applied, three PUCCH instances may be deferred, and the remaining PUCCH instances may belong to different frequency hops based on the deferred PUCCH instance. Phase coherence and/or power coherence in PUCCH instances 3, 4, 5, 6, 7, and 8 may be maintained.

Referring to FIG. 26C , frequency hopping may be performed at a boundary between an invalid symbol and a valid symbol, and the maximum number of consecutive PUCCH instances may be set. When method 3.2-4 is applied, 4 or less PUCCH instances may belong to the same frequency hop. The UE may maintain phase coherence and/or power coherence in PUCCH instances 3, 4, 5, and 6. In addition, the UE may maintain phase coherence and/or power coherence in PUCCH instances 7 and 8.

3.3 How to improve power control

In order to widen the coverage area of the PUCCH, repeated transmission of the PUCCH occasion may be indicated to the UE. The terminal may receive an RRC signaling message including information indicating a repetition transmission method (eg, repetition type) from the base station. For convenience of description, similar to the embodiment of the PUSCH occasion, the repeated transmission method of the PUCCH occasion may be classified into a PUCCH repetition type A and a PUCCH repetition type B.

When PUCCH repetition type A is used, the UE may transmit PUCCH more than once. The minimum interval between the first symbol in the first PUCCH transmission and the first symbol in the second PUCCH transmission may be one slot or one subslot. The first PUCCH transmission and the second PUCCH transmission may be adjacent PUCCH transmissions. When PUCCH repetition type B is used, the UE may transmit PUCCH twice or more. The minimum interval between the first symbol in the first PUCCH transmission and the first symbol in the second PUCCH transmission may be symbols of the PUCCH. The first PUCCH transmission and the second PUCCH transmission may be adjacent PUCCH transmissions. PUCCH repetition type A may be used to widen the coverage area of PUCCH. PUCCH repetition type B may be used to reduce an error rate and/or delay time of PUCCH.

For convenience of description, “a PUCCH being transmitted once” may be referred to as a “PUCCH instance”, and one or more PUCCH instances may constitute one PUCCH occasion.

Alternatively, the PUCCH occasion may be transmitted based on PUCCH repetition types C, D, or BB. Each of the PUCCH repetition types C, D, and BB may correspond to the above-described PUSCH repetition types C, D, and BB.

The same TPC command may be applied to all PUCCH instance(s) belonging to the PUCCH occasion. Since the number of symbols in each of the PUCCH instances may be different, the PUCCH instances may not have the same transmit power.

Transmission power applied to the PUCCH instance may be calculated based on the equation presented in the technical specification. For example, in a new radio (NR) technology standard, transmission power may be calculated based on Equation 3 below.

Here, P(i,u,q,l) may be applied to PUCCH instance i. u may represent a set of parameter(s) for calculating transmit power. q may indicate an index of a DL-RS or UL-RS used by the UE to estimate path attenuation. l may be an index of a set managing TPC commands.

P _o (u) may be a reference variable of transmit power for a PUCCH instance. When the reference RS (eg, reference variable) is u , a value corresponding to u may be indicated (eg, set) by RRC signaling. μ may be a variable for the subcarrier interval used by the PUCCH instance. PL(q) may be the amount of path attenuation of the DL calculated based on q when the reference RS is q. PL(q) may be estimated in the terminal. g(i,l) may be an accumulated value of the TPC command for the l-th power control loop.

Δ _F (i) may be set by RRC signaling. Δ _F (i) may be set differently for each PUCCH format. In addition, Δ (i) may have a different value for each PUCCH format. When PUCCH format 0 or PUCCH format 1 is used, Δ _F (i) or Δ (i) may be determined as a function of the number of bits of UCI and the number of symbols of PUCCH. If the PUCCH format 2, PUCCH format 3, or 4 PUCCH format used, Δ _F (i) or Δ (i) may be determined as a function that is determined by the amount of UCI. This function may be different depending on the encoding method applied to UCI.

M _RB (i) may be the number of RBs to which PUCCH instances are mapped. The parameters may be classified into an open loop control parameter and a closed loop control parameter. For example, the UE may measure the path attenuation by itself, and may update PL(q) based on the measured result. The above-described parameters may be open loop control parameters. For example, the terminal may receive the TPC command and may update g(i,l) based on the TPC command. The above-described parameters may be classified as closed loop control parameters.

Method 3.3-1 : Transmission power applied to a PUCCH instance may be derived according to a technical standard.

The PUCCH instance may belong to a slot (or subframe) to which a new TA, a new TPC command, or a new path attenuation is applied. In this case, TA, TPC command, or path attenuation in adjacent PUCCH instances may be applied differently.

Method 3.3-2 : The transmit power applied to the PUCCH instance may be derived from a reference PUCCH instance, and the PUCCH occasion may be transmitted by reusing the derived transmit power.

For example, the transmit power applied to the first PUCCH instance belonging to the PUCCH occasion may be equally applied to the remaining PUCCH instance(s). In addition, for all PUCCH instances belonging to the PUCCH occasion, it may be desirable for the UE not to update both the open loop control parameter and the closed loop control parameter. This operation will be described below.

Method 3.3-3 : For the transmit power applied to the PUCCH instance, the UE may not update PL(q) and/or g(i,l).

Chapter 4 Method of Extending Signal Arrival Area in Initial Access Procedure

4.1 PUSCH used in the initial access procedure

UL coverage may be interpreted as an outage probability of PUSCH. In the initial access procedure, PUSCH may mean message 3 PUSCH (eg, Msg3) or message A PUSCH (eg, MsgA). In order to extend the UL coverage, the base station may instruct the terminal that high transmission power is allocated to the PUSCH. Alternatively, in order to extend UL coverage, the number of PUSCH transmissions (eg, time resource) may be increased. "When PUSCH transmission power of a terminal located at the boundary of UL coverage is increased", interference from PUSCH transmission to other base stations may increase. Therefore, instead of increasing the transmit power, it may be desirable to transmit the PUSCH for a long time.

Method 4.1-1 : A RACH procedure performed by a UE (eg, a UE located in a boundary area) and/or parameters necessary for the RACH procedure may be indicated using a system information block (SIB) and/or a dedicated control message. . The parameters necessary for the RACH procedure and/or RACH procedure performed by the terminal located in the boundary area (eg, terminal having low reception quality) are not located in the boundary area (eg, terminal having high reception quality) It may be distinguished from the parameters required for the RACH procedure and/or the RACH procedure to be performed.

For example, a random access (RA) procedure (eg, RACH procedure, PRACH procedure) may be classified into a first RA procedure and a second RA procedure. Repeated transmission of a message (eg, Msg1, Msg2, Msg3, Msg4, MsgA, and/or MsgB) in the first RA procedure may not be performed, and in the second RA procedure, the message (eg, Msg1, Msg2) , Msg3, Msg4, MsgA, and/or MsgB) may be repeatedly transmitted. The base station may transmit the SIB and/or dedicated control message including the configuration information of the first RA procedure and the configuration information of the second RA procedure. The configuration information of the first RA procedure (eg, parameters required for the first RA procedure) may be referred to as first RA configuration information, and the configuration information of the second RA procedure includes the second RA configuration information (eg, , parameters required for the second RA procedure). The terminal may receive the first RA configuration information and the second RA configuration information from the base station. When a predefined condition is satisfied, the UE may perform the first RA procedure based on the first RA configuration information. When the predefined condition is not satisfied, the UE may perform the second RA procedure based on the second RA configuration information. In the second RA procedure, the UE may repeatedly transmit a PUSCH (eg, Msg3 or MsgA).

Here, the predefined condition may be a case in which a measurement result (eg, received signal strength, reception quality) of a signal received from the base station exceeds a threshold value. For example, the terminal may perform a measurement operation on the synchronization signal and/or the reference signal received from the base station. When the result of the measurement operation exceeds the threshold (eg, when a predefined condition is satisfied), the terminal may perform the first RA procedure using the first RA configuration information. In this case, the terminal may determine that it is not located in the boundary area. When the result of the measurement operation is less than or equal to a threshold (eg, when a predefined condition is not satisfied), the UE may perform the second RA procedure using the second RA configuration information. In this case, the terminal may determine that it is located in the boundary area.

The result of the measurement operation (eg, reference signal received power (RSRP) of the SS/PBCH block, path attenuation, the relative position of the terminal (eg, an estimate of the position), the relative position of the base station (eg, the position of the The second RA configuration information (eg, RACH configuration and/or RACH-related parameters) used when the estimated value)) is less than or equal to the threshold is the first RA used when the result of the above-described measurement operation exceeds the threshold. It may be configured independently of configuration information (eg, RACH configuration and/or RACH related parameters). That is, the RA procedure (eg, the second RA procedure) performed when the result of the measurement operation is below the threshold value is the RA procedure (eg, the first RA procedure) performed when the result of the measurement operation exceeds the threshold value procedure) can be distinguished.

The RA configuration information (eg, the first RA configuration information and/or the second RA configuration information) may include a threshold value that is a comparison criterion for the measurement operation result of the terminal. The terminal may determine whether it is located in the boundary area using the threshold value. When the result of the measurement operation performed on the terminal is less than or equal to the threshold, the terminal may determine that it is located in the boundary area. In this case, the UE may perform a new RA procedure (eg, a random access procedure, an initial access procedure). The new RA procedure may be a second RA procedure using the second RA configuration information.

In the new RA procedure, "specific PRACH occasion", "use of specific PRACH preamble index", "repeated transmission of PRACH preamble (eg, Msg1)", "use of appropriate PRACH preamble format", "repeated transmission of Msg2 ", "repeated transmission of Msg3", "repeated transmission of Msg4", "repeated transmission of MsgA", and/or "repeated transmission of MsgB" may be supported. Indicates whether the terminal supports "repeated transmission of Msg1", "repeated transmission of Msg2", "repeated transmission of Msg3", "repeated transmission of Msg4", "repeated transmission of MsgA", and/or "repeated transmission of MsgB" information to be transmitted from the terminal to the base station in the initial access procedure or in a separate procedure after the initial access procedure.

When the result of the measurement operation performed by the terminal exceeds the threshold, the terminal may determine that it is not located in the boundary area. In this case, the UE may perform the existing RA procedure. The existing RA procedure may be a first RA procedure using the first RA configuration information. In the existing RA procedure, "repeated transmission of Msg1", "repeated transmission of Msg2", "repeated transmission of Msg3", "repeated transmission of Msg4", "repeated transmission of MsgA", and/or "repeated transmission of MsgB" are may not be supported.

The RA configuration information may include parameters for transmission of the PRACH preamble. For example, the RA configuration information may include a PRACH mask and/or an allowable PRACH preamble index (eg, a set of PRACH preamble indexes).

The RA configuration information may include resource mapping information between a PRACH (eg, Msg1 or MsgA) and a PUSCH (eg, Msg3 or MsgB). For example, the slot offset between the transmission slot of the PRACH and the transmission slot of the PUSCH may be included in the RA configuration information. The UE may derive the first slot in which the PUSCH is transmitted using the slot offset.

The RA configuration information may include repeated transmission information of PUSCH. The repeated transmission information of the PUSCH may be independent of the resource mapping information between the PRACH and the PUSCH. In this case, the repeated transmission information of the PUSCH includes time resource information (eg, time resource location, information indicating the time resource of the first PUSCH (eg, offset)), the number of repetitions, and/or MCS. can

The base station may determine whether the terminal is located in the boundary area based on the PRACH preamble format, the PRACH mask, and/or the resource (eg, PRACH occasion) used in the RA procedure. That is, the base station may determine whether the result of the measurement operation in the terminal is less than or equal to a threshold value. For example, the PRACH preamble for the first RA procedure may be distinguished from the PRACH preamble for the second RA procedure, and the PRACH mask for the first RA procedure may be distinguished from the PRACH mask for the second RA procedure, The PRACH occasion for the first RA procedure may be distinguished from the PRACH occasion for the second RA procedure.

Alternatively, the PRACH preamble for the first RA procedure may be distinguished from the PRACH preamble for the second RA procedure, and the PRACH mask for the first RA procedure may be distinguished from the PRACH mask for the second RA procedure. Even in this case, the PRACH occasion for the first RA procedure may not be distinguished from the PRACH occasion for the second RA procedure. The PRACH occasion for the first RA procedure and the PRACH occasion for the second RA procedure may share the same PRACH occasion. That is, the PRACH occasion for the first RA procedure and the PRACH occasion for the second RA procedure may be a shared PRACH occasion. When the PRACH occasion for the first RA procedure and the PRACH occasion for the second RA procedure are configured as a shared PRACH occasion, the first RA procedure (eg, the PRACH preamble for the first RA procedure) is a PRACH mask (or PRACH submask) may be distinguished from the second RA procedure (eg, the PRACH preamble for the second RA procedure).

Here, the PRACH mask may be subdivided into PRACH submask(s). That is, the PRACH submask may be introduced. One PRACH submask may be used for the first RA procedure, and another PRACH submask may be used for the second RA procedure.

When the UE is located in the boundary region (eg, when the result of a measurement operation in the UE is less than or equal to a threshold), the base station transmits a MAC UL grant for allocating a PUSCH (eg, PUSCH resource) to the UE through the PDSCH can The MAC UL grant may be referred to as a UL grant.

28 is a conceptual diagram illustrating a first embodiment of a MAC random access response (RAR) or fallback RAR.

Referring to FIG. 28 , MAC RAR or fallback RAR may include a timing advance (TA) command, a UL grant (eg, MAC UL grant), and a temporary cell (TC)-radio network temporary identifier (RNTI). . The MAC UL grant may include one or more fields defined in Table 3 below.

When an RRC connection is not established between the terminal and the base station, the base station may inform the terminal of the number of repetitions of the PUSCH by using another method instead of RRC signaling. For example, in the PUSCH (eg, PUSCH resource) allocation step, the base station may transmit a MAC RAR (or fallback RAR) including information indicating the number of repetitions of the PUSCH to the terminal.

Method 4.1-2 : Information indicating the number of repetitions of the PUSCH (eg, Msg3 or MsgA) may be included in the MAC RAR or the fallback RAR. For example, information indicating the number of repetitions of the PUSCH may be included in a UL grant field (or another field) of a MAC RAR (or fallback RAR).

In the initial access procedure, the PUSCH may be scheduled by the PDSCH (eg, MAC UL grant). One or more bits included in the MAC UL grant may indicate the number of repetitions (K) of the PUSCH. The UE may repeatedly transmit the PUSCH using the same time resource in each of K consecutive slots. The same time resource in each of K consecutive slots may be indicated by a start and length indicator value (SLIV). That is, the same SLIV may be applied to K consecutive slots. Alternatively, the UE may repeatedly transmit the PUSCH K times using the minimum slots in which the PUSCH can be transmitted. In this case, the PUSCH may be repeatedly transmitted using the same time resource in each of the slots.

The MAC UL grant may be expressed by many bits to include a field indicating the number of repetitions of the PUSCH. Reserved (reserved) bit(s) in the MAC RAR (or fallback RAR) may be used to indicate the number of repetitions of the PUSCH. Reserved bit(s) indicating the number of repetitions of the PUSCH may be included in the MAC UL grant. Alternatively, the reserved bit(s) of the MAC RAR (or fallback RAR) are “that repeated transmission of PUSCH is performed” or “that PUSCH is transmitted once (eg, that repeated transmission of PUSCH is not performed)” " can be instructed. In this case, the number of repetitions of the PUSCH may be indicated to the UE by the MAC UL grant. The index indicated by the base station may implicitly indicate the number of repetitions of the PUSCH. In this case, the terminal may check the number of repetitions of the PUSCH based on the index indicated by the base station. MAC RAR (or fallback RAR) may include a field explicitly indicating the number of repetitions of PUSCH.

Alternatively, in the PUSCH (eg, PUSCH resource) allocation step, the MAC RAR (or fallback RAR) may implicitly indicate to the UE the number of repetitions of the PUSCH.

Method 4.1-3 : The TDRA default table A referenced in the MAC UL grant may be extended. The extended TDRA default table A may be referred to as a TDRA default table B. The TDRA default table B may indicate the PUSCH time resource including the number of repetitions of the PUSCH. That is, the information included in the TDRA default table B may indicate the number of repetitions of the PUSCH.

For example, the TDRA default table B may include (eg, indicate) one or more of "SLIV", "PUSCH mapping type", and "index including two or more K2s". The number of SLIVs included in the TDRA default table B may be interpreted as the number of repetitions of the PUSCH. The number of PUSCH mapping types included in the TDRA default table B may be interpreted as the number of repetitions of the PUSCH.

For another example, the TDRA default table B may include one or more of “SLIV”, “PUSCH mapping type”, “K2 (eg, an index containing two or more K2s)”, and “number of repetitions of PUSCH”. can

Method 4.1-4 : In method 4.1-3, the MAC RAR (or fallback RAR) may include a bit indicating the use (or selection) of the TDRA default table A or the TDRA default table B. The size of the corresponding bit may be 1 bit.

The UE refers to the TDRA default table (eg, TDRA default table A or TDRA) for PUSCH transmission based on information (eg, an additional 1 bit) included in the MAC RAR (or fallback RAR) received from the base station. You can check the default table B).

Information included in the MAC UL grant of the MAC RAR (or the fallback RAR) may indicate a TDRA default table used for repeated transmission of the PUSCH. In this case, the UE may refer to the TDRA default table indicated by information included in the MAC UL grant for repeated transmission of the PUSCH. The TDRA default table may include information indicating the number of repetitions of Msg3 or MsgA.

The base station may instruct (eg, set) the TDRA table or TDRA list for interpreting the TDRA of the PUSCH to the terminal using system information. For example, when SIB1 not including pusch-configCommon is received from the base station, the terminal may determine that the TDRA default table A is used, and may derive the TDRA of the PUSCH from the TDRA default table A. Alternatively, when SIB1 including pusch-configCommon is received from the base station, the UE may check the TDRA of PUSCH by referring to the TDRA table (or TDRA list) indicated by pusch-configCommon. The TDRA index included in the RAR UL grant may be associated with different tables according to SIB1.

Method 4.1-5 : The TDRA list included (or indicated) in pusch-configCommon may include information indicating the number of repetitions of PUSCH. One TDRA index may indicate one or more of the PUSCH mapping type, SLIV, K2, and the number of repetitions of PUSCH.

The TDRA list included by pucch-configCommon can be utilized in DCI of other scenarios as well as RAR UL grants. For example, even when DCI format 0_0 (eg, cyclic redundancy check (CRC) of DCI format 0_0) is scrambled with C-RNTI, MCS-C-RNTI, CS-RNTI, or TC-RNTI, the terminal The referenced TDRA list may include a TDRA index indicating repeated transmission of the PUSCH (eg, the number of repetitions of the PUSCH). The TDRA table referenced by the TDRA index included in DCI (eg, DCI format 0_0) may include information indicating the number of repetitions of a PUSCH (eg, Msg3 or MsgA). These methods will be described in detail in the examples below.

When the PUSCH is repeatedly transmitted, the size (eg, TB size) of the PUSCH (eg, PUSCH message) is the MCS, time resource, and/or frequency resource indicated by the MAC RAR (or fallback RAR). can be derived using Alternatively, the size of the PUSCH may be indicated (eg, configured) to the UE by higher layer signaling.

Meanwhile, a message type (eg, Messagetype) of a common control channel (CCCH) (eg, CCCH1) included in the PUSCH may be configured. For example, the CCCH message type may be classified into rrcSetupRequest, rrcResumeRequest, rrcReestablishmentRequest, rrcSystemInfoRequest, and the like. The type of message of CCCH1 may be divided into rrcResumeRequest1 and the like. When one type of message is indicated, cause, which is a value of a field specifying the type of message, may be determined. For example, when rrcSetupRequest of CCCH is indicated, EstablishmentCause which is the purpose of rrcSetupRequest may be indicated. When rrcResumeRequest of CCCH is indicated, ResumeCause, which is the purpose of rrcResumeRequest, may be indicated. When rrcReestablishmentRequest of CCCH is indicated, ReestablishmentCause, which is the purpose of rrcReestablishmentRequest, may be indicated. When rrcResumeRequest1 of CCCH1 is indicated, ResumeCause, which is the purpose of rrcResumeRequest1, may be indicated.

Here, EstablishmentCause may have a value of one of emergency, highPriorityAccess, mt-Access, mo-Signalling, mo-Data, mo-VoiceCall, mo-VideoCall, mo-SMS, mps-PriorityAccess, and mcs-PriorityAccess. ResumeCause may have a value of one of emergency, highPriorityAccess, mt-Access, mo-Signalling, mo-Data, mo-VoiceCall, mo-VideoCall, mo-SMS, rna-Update, mps-PriorityAccess, and mcs-PriorityAccess . ReestablishmentCause may have one of reconfigurationFailure, handoverFailure, and otherFailure.

Method 4.1-6 : When the PUSCH is repeatedly transmitted, the cause of the CCCH (eg, CCCH1) included in the PUSCH may be limited, and one value among the limited causes may be indicated to the UE.

When limited to a specific service, the PUSCH may be repeatedly transmitted. For example, when the terminal located in the boundary area performs the initial access procedure, rrcSetupRequest, rrcResumeRequest, ReestablishmentCause, or rrcResumeRequest1 may be indicated as a message type of CCCH or CCCH1. Here, cause may be indicated by one of all or part of the values suggested in the technical specification. When the terminal performs an initial access procedure to support voice over internet protocol (VoIP), an appropriate cause may be indicated in the initial access procedure for VoIP. For example, for an initial access procedure for VoIP, a cause may be selected from all or part of mo-Signalling, mo-Data, mo-VoiceCall, mo-VideoCall, and mo-SMS.

As another method, in Method 4.1-6, a cause may be indicated among some values of existing causes, but a new cause limitedly applied to repeated transmission of PUSCH may be introduced.

4.1.1 PUSCH Allocated by Fallback DCI

After the RRC connection establishment between the UE and the base station is completed, the UE may transmit a PUSCH (eg, Msg3) allocated by the fallback DCI (eg, DCI format 0_0). Based on the technical standard, the time resource of the PUSCH may be determined based on the TDRA divided according to a search space in which the scheduling DCI is transmitted. Based on Tables 4 and 5 below, the UE may obtain the TDRA list through default A (eg, TDRA default table A) or default B (eg, TDRA default table B). Tables 4 and 5 may be DCI format 0_0 in a UE-specific search space and PDSCH TDRA for a common search space. Alternatively, the UE may use pusch-ConfigCommon or a TDRA list included in pusch-Config.

Here, TB may include at least Msg3. The above-described method may be applied when DCI format 0_0 scrambled with TC-RNTI is used. Alternatively, the above-described method may be applicable even when DCI format 0_0 scrambled with C-RNTI, MCS-C-RNTI, or CS-RNTI is used. When considering Msg3, the RRC connection between the terminal and the base station may not necessarily be established.

Method 4.1-7 : In the TDRA list included in pusch-ConfigCommon, the TDRA index may explicitly indicate the number of repetitions of PUSCH. For example, the TDRA index may include information explicitly indicating the number of repetitions of the PUSCH.

If some TDRA indexes in the TDRA list indicated by pusch-Config indicate the number of repetitions of PUSCH, the scheduling DCI may be transmitted in any common search space not associated with CORESET 0 or UE-specific search space. In this case, the above-described TDRA list may be applied. Accordingly, the base station may instruct the terminal to repeatedly transmit the PUSCH by using an appropriate TDRA index.

In addition to the above cases, when the TDRA list is not indicated to the terminal by RRC signaling (eg, pusch-ConfigCommon, or pusch-Config), the terminal applies a TDRA index according to the TDRA default table A or TDRA default table B can do. According to method 4.1-7, "if PUSCH is assigned by MAC RAR or MAC fallback RAR" or "scheduling DCI is transmitted in any common search space or UE specific search space related to (or not related to) CORESET 0 If ", the above-described operation may be performed.

For example, the TDRA list may include one or more of "SLIV", "PUSCH mapping type", and "index including two or more K2s". The number of SLIV and/or PUSCH mapping types included in the TDRA list may be interpreted as the number of repetitions of the PUSCH.

For example, the TDRA list may include the number of repetitions of SLIV, PUSCH mapping type, K2, and/or PUSCH.

4.2 PDSCH allocated in initial access procedure and fallback DCI

In the case of "when an RRC connection is not established between the UE and the base station", "in case the RRC connection is deactivated", or "in the case of reconfiguring the RRC connection", the PDSCH may be scheduled according to DCI format 1_0. In this case, in order to widen the coverage area of the PDSCH, the base station may repeatedly transmit the PDSCH. That is, the UE may repeatedly receive the PDSCH.

Method 4.2-1 : DCI format 1_0 may indicate repeated reception of PDSCH.

A field (eg, a separate field) that explicitly indicates the number of repetitions of the PDSCH may be included in DCI format 1_0. Alternatively, the number of repetitions of the PDSCH may be implicitly derived from the TDRA index for allocating the PDSCH. For example, the TDRA index of the PDSCH allocated in DCI format 1_0 may refer to a TDRA table including a plurality of elements. Based on Tables 6 to 8 below, the TDRA table referenced by the UE may be determined according to “a multiplexing pattern of SS/PBCH block and CORESET” and/or “whether PDSCH-ConfigCommon and PDSCH-Config are configured”. Tables 6 to 8 may be PDSCH TDRAs for DCI format 1_0.

Method 4.2-2 : In method 4.2-1, some TDRA indexes of TDRA default tables A, B, and/or C may be extended, and the extended TDRA index is the number of PDSCH receptions (eg, the number of repetitions of PDSCH) may include (eg, indicate).

In the TDRA default table, the TDRA index may indicate (eg, include) the index (dmrs-TypeeA-Position) of the first symbol of the PDSCH DM-RS resource, the PDSCH mapping type, K0, S, and L. When method 4.2-2 is applied, the TDRA index may additionally include (eg, indicate) the number of repetitions of the PUSCH.

When the UE repeatedly receives the PDSCH, the time resource for receiving the PDSCH may be two or more slots. When the number of repetitions of the PDSCH is K in a communication system supporting FDD, the UE may receive the PDSCH in K consecutive slots. The same DM-RS start symbol, mapping type (eg, PDSCH mapping type), S, and L may be applied in each of the slots. K0 indicated by DCI format 1_0 may indicate the first slot in which the PDSCH is received.

For convenience of description, a PDSCH occasion may consist of one or more PDSCH instances, and mapping of one PDSCH instance (eg, a PDSCH instance belonging to the same PDSCH occasion) may be the same within a slot.

Method 4.2-3 : When some symbols of the PDSCH instance overlap the SS/PBCH block and/or the Type0-PDCCH CSS set, the UE may not receive the corresponding PDSCH instance.

In a communication system supporting TDD, a UE may check whether a PDSCH instance is received in consideration of a slot pattern. That is, it may be necessary to interpret the time window in which the PDSCH occasion is received in the terminal. The time window may vary depending on "a search space set in which DCI format 1_0 is received" and/or "whether a slot pattern is set in the terminal". Alternatively, the time window may be independent of the search space set and/or slot pattern.

Method 4.2-4 : In order to derive a valid PDSCH instance in method 4.2-3, the UE may use a common slot pattern (eg, tdd-UL-DL-ConfigurationCommon) and a TDRA index obtained from system information. For example, an effective PDSCH instance may be determined based on a common slot pattern and/or a TDRA index.

Method 4.2-5 : In order to derive a valid PDSCH instance in method 4.2-3, the UE may use a UE-specific slot pattern (eg, tdd-UL-DL-ConfigurationDedicated) and a TDRA index. For example, the effective PDSCH instance may be determined based on a UE-specific slot pattern and/or TDRA index.

In Methods 4.2-4 and 4.2-5, the UE may assume that the PDSCH instance is received only in symbols configured as DL symbols. The UE may assume that the PDSCH instance is not received in the symbol configured as the FL symbol or the UL symbol.

In the method of counting the number of repetitions of the PUSCH, if the PDSCH instance is not received, the UE may regard the PDSCH instance as the number of repetitions of the PUSCH. Alternatively, if a PDSCH instance is not received, the UE may not regard the PDSCH instance as the number of repetitions of the PUSCH. If the non-received PDSCH instance is regarded as the number of repetitions of the PUSCH, the time window for the PDSCH occasion received by the UE may be indicated by (only) DCI format 1_0. When the number of times of PDSCH instance reception is the same as the value indicated in DCI format 1_0, the time window for the PDSCH occasion received by the UE may be determined in consideration of DCI format 1_0 as well as the slot pattern.

4.3 PUCCH used in initial access procedure

The base station may indicate (eg, configure) the PUCCH resource set to the terminal using RRC signaling. In this case, one or more PUCCH resource sets may be indicated, and each of one PUCCH resource set may include one or more PUCCH resources. The UE may select a PUCCH resource set according to the number of UCI bits, and may select one PUCCH resource belonging to the selected PUCCH resource set. In this case, the base station may indicate the PUCCH resource index to the terminal using a specific field of DCI and/or RRC signaling.

When it is necessary to extend the UL coverage of the terminal, the number of repetitions of the PUCCH may be indicated by RRC signaling of the base station. In this case, the UE may repeatedly transmit the PUCCH indicated by one PUCCH resource index.

"When the RRC connection between the terminal and the base station is not established", "when the RRC connection is re-established", or "when the RRC connection is established, but information exchange between the terminal and the base station is not sufficiently performed (eg, capability signaling is If not performed)", the UE cannot use the above-described PUCCH resource set. In this case, a separate PUCCH resource set may be provided to the UE. For example, the PUCCH resource set defined in Table 9 below may be used. Table 9 may be PUCCH resource sets before dedicated (dedicated) PUCCH resource configuration.

Based on Table 9, PUCCH format 0 or 1 may be used, the bandwidth may be limited to 1 PRB, and a maximum of 14 symbols may be used. In order to extend the UL coverage, the UE may allocate a lot of transmit power. Alternatively, in order to extend UL coverage, the UE may transmit PUCCH for a long time. For example, the UE may repeatedly transmit PUCCH. "When the terminal is located in the boundary area of the UL coverage and the transmission power of the terminal is increased", interference to other base stations by a signal/channel transmitted from the corresponding terminal may increase. Therefore, rather than increasing the transmission power of the terminal, it may be preferable for the terminal to transmit the PUCCH for a long time.

According to method 4.1-1, the procedure and/or parameter(s) applied to the RA procedure may be indicated by the SIB, and the procedure and/or parameter(s) may be differently indicated for a terminal located in the boundary area. can For example, the first RA configuration information for the terminal not located in the boundary area may be set independently of the second RA configuration information for the terminal located in the boundary area. The number of repetitions of the PUCCH may be implicitly indicated by the SIB. The UE may perform a measurement operation for DL-RS (eg, SS/PBCH block), and different RA procedures (eg, according to the comparison result between the measured result (eg, RSRP) and the threshold value) For example, the first RA procedure or the second RA procedure) may be performed.

For example, the SIB may include information indicating the number of repetitions of the HARQ-ACK for the PDSCH (eg, the number of repeated transmissions). Since the SIB includes information for a UE not located in the boundary region, information indicating the number of repetitions of the HARQ-ACK may be transmitted in another step of the RA procedure.

Method 4.3-1 : The PDSCH (eg, MAC RAR or fallback RAR) may include information indicating the number of repetitions of the PUCCH.

The MAC RAR (or fallback RAR) may include information indicating the number of repetitions of HARQ-ACK for PDSCH as well as MAC UL grant.

A MAC RAR (or a fallback RAR) may be configured as shown in FIG. 28 . One or more bits included in MAC RAR (or fallback RAR) may indicate the number of repetitions of HARQ-ACK for PDSCH.

MAC RAR (or fallback RAR) may indicate repeated transmission of PUSCH. In this case, the MAC RAR (or fallback RAR) may include both information indicating the number of repetitions of the PUSCH and information indicating the number of repetitions of the HARQ-ACK for the PDSCH.

Method 4.3-2 : In method 4.3-1, the number of repetitions of PUSCH may be (re)used as the number of repetitions of PUCCH for PDSCH.

When the number of repetitions is indicated, the number of repetitions may be applied to both PUSCH transmission and PDSCH HARQ-ACK transmission. According to method 4.3-2, the amount of bits additionally included in the MAC RAR (or fallback RAR) may be reduced.

Method 4.3-3 : PDSCH may include information indicating the number of repetitions.

A MAC protocol data unit (PDU) may include information corresponding to contention resolution and information on the number of repetitions (eg, information on the number of repetitions of HARQ-ACK for PDSCH). In this case, there may be a problem in backward compatibility of the terminal.

Method 4.3-4 : Scheduling DCI for allocating PDSCH may include information indicating the number of repetitions.

The scheduling DCI may include one field indicating the number of repetitions of HARQ-ACK for the PDSCH. For example, the PDSCH may be allocated by DCI format 0_0 based on TC-RNTI. In this case, the scheduling DCI may further include information indicating the number of repetitions of the HARQ-ACK, and the base station may transmit the corresponding scheduling DCI to the terminal. To support this operation, when DCI format 0_0 is scrambled by TC-RNTI, a reserved bit may be additionally utilized. For example, a downlink assignment index (DAI) field may be reused. In this case, the value indicated by the DAI field may be interpreted as the number of repetitions of HARQ-ACK.

Method 4.3-5 : The PUCCH resource set (eg, information on the PUCCH resource set) may include information indicating the number of repetitions of HARQ-ACK.

When the UE does not utilize the PUCCH resource set indicated by RRC signaling, the UE may utilize the PUCCH resource set defined in the technical specification (eg, the PUCCH resource set defined in Table 9). In this case, repeated transmission of HARQ-ACK for the PDSCH may not be indicated. The reason is that format 0 or format 1 for HARQ-ACK can be transmitted in (only) one slot in PUCCH. According to method 4.3-5, the time resource can be extended and expressed in the PUCCH resource set defined in the technical standard. For example, the information of the PUCCH resource set may include information transmitted in two or more slots. For example, in Table 9, information indicating the number of repetitions of HARQ-ACK may be additionally included.

Method 4.3-6: PUCCH resource information may include information indicating the number of repetitions of HARQ-ACK.

For example, an index indicating a PUCCH resource belonging to the PUCCH resource set defined in Table 9 may include the number of repetitions of HARQ-ACK. According to Method 4.3-6, the number of repetitions of PUCCH (eg, the number of repetitions of HARQ-ACK) may be derived differently even in the same PUCCH resource set.

In another proposed method, the number of repetitions of the PUCCH may also be indicated together with a slot (eg, a sub-slot) in which the PUCCH is transmitted.

Method 4.3-7 : The offset of the slot (eg, sub-slot) in which the PUCCH is transmitted and the number of repetitions of the PUCCH may be indicated to the UE in the form of an index.

The UE may receive the DL-DCI and may know the offset of the slot (eg, sub-slot) in which the PUCCH is transmitted based on the index included in the DL-DCI. According to method 4.3-7, the above-mentioned index can be extended. Based on the index indicated to the UE by RRC signaling, the number of repetitions of the PUCCH as well as the offset of the slot (eg, sub-slot) may be derived. The UE may repeatedly transmit the PUCCH in slots (eg, subslots) as many as the number of repetitions indicated by RRC signaling. In this case, the UE may apply the same index (eg, the same resource index) to each of the slots (eg, sub-slots).

In a communication system supporting TDD, the UE may check whether a PUCCH instance is transmitted in consideration of a slot pattern. In this case, it may be necessary to interpret the time window in which the PUCCH occasion is received in the terminal. Interpretation of the time window may vary according to a search space set in which DCI format 1_0 is received and/or a slot pattern configured in the terminal. Alternatively, the interpretation of the time window may be independent of the search space set and/or slot pattern.

Method 4.3-8 : In order to derive a valid PUCCH instance, the terminal may utilize a common slot pattern (eg, tdd-UL-DL-ConfigurationCommon) included in the system information received from the base station.

Method 4.3-9 : In order to derive a valid PUCCH instance, the UE may utilize a UE-specific slot pattern (eg, tdd-UL-DL-ConfigurationDedicated).

In Methods 4.3-8 and 4.3-9, the UE may assume that the PUCCH instance is transmitted only in symbols configured as UL symbols. The UE may assume that a PUCCH instance is not transmitted in a symbol configured as a FL symbol, a symbol configured as a DL symbol, a symbol in which an SS/PBCH block is transmitted, and/or a symbol belonging to the Type0-PDCCH CSS set.

In the method of counting the number of repetitions, when the PUCCH instance is not transmitted, the UE may not regard the non-transmitted PUCCH instance as the number of repetitions. When the transmission number of the PUCCH instance is the same as the value indicated in DCI format 1_0, the time window for the PUCCH occasion may be determined in consideration of DCI format 1_0 as well as the slot pattern.

4.4 How to interpret time resources according to RRC connection status

When the PUSCH is repeatedly transmitted, a pattern of slots in which the PUSCH is transmitted as well as the number of repetitions of the PUSCH can be derived. When the terminal operates in RRC_CONNECTED, the base station may indicate (or set) the number of repetitions of the PUSCH and the slot pattern to the terminal by using RRC signaling. When the UE operates in RRC_IDLE or RRC_INACTIVE, since the base station cannot perform RRC signaling to a specific UE, the UE can derive the number of repetitions and the slot pattern of the PUSCH using system information.

In order to indicate the slot pattern to the terminal, a plurality of steps may be required. A common slot pattern (eg, tdd-UL-DL-ConfigurationCommon) configured in units of cells and a slot pattern (eg, tdd-UL-DL-ConfigurationDedicated) configured in units of terminals are indicated to the UE by RRC signaling (or set). Also, DCI format 2_0 may indicate a pattern for some slots. Accordingly, a UE using only system information may derive a slot in which PUSCH transmission is possible using a common slot pattern. This operation can also be applied to the transmission operation of the PUCCH.

To indicate repeated transmission of PUSCH, MAC RAR (or fallback RAR) and/or fallback DCI (eg, DCI format 0_0) may be used. Supertransmission of Msg3 PUSCH (ie, Msg3) may be indicated by MAC RAR (or fallback RAR), and retransmission of Msg3 PUSCH may be indicated by fallback DCI.

In order to indicate repeated transmission of the PUSCH, a fallback DCI (eg, DCI format 1_0) may be used. Transmission of HARQ-ACK (eg, PUCCH) for Msg4 PDSCH (ie, Msg4) may be indicated by a fallback DCI.

Method 4.4-1 : "If the RRC connection is not established between the terminal and the base station, and the terminal repeatedly transmits a UL signal and/or channel (eg, PUSCH or PUCCH)", the terminal uses a common slot pattern, SS/PBCH A valid slot may be derived in consideration of the block and/or the Type0-PDCCH CSS set.

Here, the effective slot may mean a time resource including (only) UL symbols. The reason is that when only a common slot pattern is utilized, transmission of a PUSCH or PUCCH in a semi-static FL symbol may not be valid. This operation may be similar to that of not using a semi-static FL symbol when DCI format 2_0 is not received.

The number of repetitions may correspond to the number of slots in which the terminal actually transmits. The number of repetitions of the PUSCH (eg, Msg3 or MsgA) may be determined based on the number of valid slots. For repeated transmission K times, K slots may be required in a communication system supporting FDD. In this case, if there are K valid slots, the UE may repeatedly transmit the PUSCH (eg, Msg3 or MsgA) K times. For repeated transmission K times, K or more slots may be required in a communication system supporting TDD. In this case, if there are K or more valid slots, the UE may repeatedly transmit the PUSCH (eg, Msg3 or MsgA) K times. This operation may be PUSCH repetition type C.

Method 4.4-2 : In method 4.4-1, PUSCH repetition type C may be applied.

On the other hand, when "the RRC connection between the terminal and the base station is established" or "the RRC connection between the terminal and the base station is deactivated", the terminal may perform a PDSCH reception operation or a PUSCH transmission operation based on the received fallback DCI. . Here, the PDSCH may be repeatedly received. This operation has been described in Method 4.2-1 and the like. In addition, the PUCCH including the HARQ-ACK for the PDSCH may be repeatedly transmitted. This operation was described in Method 4.3-4, Method 4.3-5, and Method 4.3-6. In addition, PUSCH may be repeatedly transmitted. This operation was described in Methods 4.1-7.

4.5 Frequency resource analysis method and coherence application method

In the initial access procedure, the UE may perform a separate RA procedure. For example, the base station may inform the terminal of the number of repetitions of the Msg3 PUSCH by using a UL grant belonging to the MAC RAR or a separate UL grant. The UE may check the number of repetitions of the Msg3 PUSCH based on the UL grant received from the base station, and may repeatedly transmit the Msg3 PUSCH to the base station.

The terminal may have the ability to maintain coherence. Alternatively, the terminal may not have the ability to maintain coherence. The UE may transmit an RRC signaling message including information indicating whether to support the ability to maintain coherence to the base station. In the RA procedure, the terminal may transmit "information indicating whether repeated Msg3 PUSCH transmission is supported" or "information indicating whether repeated Msg3 PUSCH transmission is required" to the base station. In addition, the terminal may transmit information indicating whether to support the ability to maintain coherence together with the above-described information to the base station. The UE may maintain coherence in K times Msg3 PUSCH repeated transmissions. K may be defined in technical specifications. The reason is that the base station cannot know the terminal capability in the initial access procedure.

In a separate RA procedure, the UE may repeatedly transmit Msg3 PUSCH. In this case, the inter-slot frequency hopping operation and the operation for coherence may be performed based on a combination of one or more methods among methods according to 2.2, 2.3, 2.4, and 2.5 described above.

The methods according to the present invention may be implemented in the form of program instructions that can be executed by various computer means and recorded in a computer-readable medium. The computer-readable medium may include program instructions, data files, data structures, etc. alone or in combination. The program instructions recorded on the computer-readable medium may be specially designed and configured for the present invention, or may be known and available to those skilled in the art of computer software.

Examples of computer-readable media include hardware devices specially configured to store and carry out program instructions, such as ROM, RAM, flash memory, and the like. Examples of program instructions include not only machine language codes such as those generated by a compiler, but also high-level language codes that can be executed by a computer using an interpreter or the like. The hardware device described above may be configured to operate as at least one software module to perform the operations of the present invention, and vice versa.

Although it has been described with reference to the above embodiments, it will be understood by those skilled in the art that various modifications and changes can be made to the present invention without departing from the spirit and scope of the present invention as set forth in the claims below. will be able

Claims (20)

A method of operating a terminal in a communication system, comprising:
Receiving first random access (RA) configuration information and second RA configuration information from a base station;
transmitting Msg1 to the base station based on the second RA configuration information;
receiving Msg2, which is a response to the Msg1, from the base station; and
It includes the step of repeatedly transmitting Msg3 to the base station K times,
The first RA configuration information is used when the first condition is satisfied, the Msg3 is not repeatedly transmitted in the first RA procedure according to the first RA configuration information, and the second RA configuration information is the first condition It is used when not satisfied, and in the second RA procedure according to the second RA configuration information, the Msg3 is repeatedly transmitted, and the K is a natural number. The method according to claim 1,
The method of operation of the terminal,
Before transmitting the Msg1, the method further comprising the step of transmitting information indicating whether the terminal supports the repeated transmission of the Msg3 to the base station. The method according to claim 1,
A first RA preamble indicated by the first RA configuration information is distinguished from a second RA preamble indicated by the second RA configuration information, and the Msg1 is generated based on the second RA preamble, How the terminal operates. The method according to claim 1,
A first PRACH occurrence indicated by the first RA configuration information is the same as a second PRACH occurrence indicated by the second RA configuration information, and the Msg1 according to the second RA configuration information is a PRACH A method of operating a terminal, which is distinguished from Msg1 according to the first RA configuration information by a mask. The method according to claim 1,
The first condition is a case in which the measurement result of the signal received from the base station exceeds a threshold value, and the threshold value is included in at least one of system information, the first RA configuration information, and the second RA configuration information, How the terminal operates. The method according to claim 1,
The second RA configuration information includes information indicating the K, the operating method of the terminal. The method according to claim 1,
The number of start and length indicator values (SLIV) included in a time domain resource assignment (TDRA) table referenced by an uplink (UL) grant included in the Msg2 indicates the K, the method of operating a terminal. The method according to claim 1,
The K is indicated by an index included in the TDRA table referenced by the UL grant included in Msg2. The method according to claim 1,
The UL grant included in the Msg2 includes information indicating a TDRA table used for repeated transmission of the Msg3, and the TDRA table includes information indicating the K. The method according to claim 1,
The K is determined based on the number of valid slots in which repeated transmission of the Msg3 is possible. The method according to claim 1,
The method of operation of the terminal,
Further comprising the step of receiving DCI (downlink control information) including information indicating the K from the base station,
The Msg3 is repeatedly transmitted according to the K indicated by the DCI. A method of operating a base station in a communication system, comprising:
generating first random access (RA) configuration information used when a first condition is satisfied;
generating second RA configuration information used when the first condition is not satisfied;
transmitting the first RA configuration information and the second RA configuration information to a terminal;
receiving Msg1 from the terminal based on the second RA configuration information;
transmitting Msg2, which is a response to the Msg1, to the terminal; and
It includes the step of repeatedly receiving Msg3 from the terminal K times,
The Msg3 is not repeatedly transmitted in the first RA procedure according to the first RA configuration information, the Msg3 is repeatedly transmitted in the second RA procedure according to the second RA configuration information, and K is a natural number. Way. 13. The method of claim 12,
The method of operation of the base station,
Prior to the reception of the Msg1, the method further comprising the step of receiving information indicating whether the terminal supports the repeated transmission of the Msg3 from the terminal. 13. The method of claim 12,
A first RA preamble indicated by the first RA configuration information is distinguished from a second RA preamble indicated by the second RA configuration information, and the Msg1 is generated based on the second RA preamble, How the base station works. 13. The method of claim 12,
A first PRACH occurrence indicated by the first RA configuration information is the same as a second PRACH occurrence indicated by the second RA configuration information, and the Msg1 according to the second RA configuration information is a PRACH A method of operating a base station, which is distinguished from Msg1 according to the first RA configuration information by a mask. 13. The method of claim 12,
The first condition is a case in which the measurement result of the signal received from the base station exceeds a threshold value, and the threshold value is included in at least one of system information, the first RA configuration information, and the second RA configuration information, How the base station works. 13. The method of claim 12,
The second RA configuration information includes information indicating the K, the base station operating method. 13. The method of claim 12,
The number of start and length indicator values (SLIV) included in a time domain resource assignment (TDRA) table referenced by an uplink (UL) grant included in Msg2 or an index included in the TDRA table indicates the K, base station how it works. 13. The method of claim 12,
The UL grant included in the Msg2 includes information indicating a TDRA table used for repeated transmission of the Msg3, and the TDRA table includes information indicating the K. 13. The method of claim 12,
The K is determined based on the number of valid slots in which repeated transmission of the Msg3 is possible.

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