WO2018026205A1 - Method for transmitting uplink control information in wireless communication system and device therefor - Google Patents

Abstract

A method by which a terminal transmits uplink control information to a base station in a wireless communication system is disclosed. Particularly, the method comprises the steps of: setting beam information on at least one subframe; transmitting first uplink control information on a subframe corresponding to a beam for the terminal on the basis of the set beam information; allowing a first timer corresponding to the type of the first uplink control information to count; and transmitting, in the subframe corresponding to the beam for the terminal and positioned at a point in time after the counting of the first timer has expired, second uplink control information, which is the same type as the first uplink control information.

Description

Method and apparatus for transmitting uplink control information in wireless communication system

The present invention relates to a method and apparatus for transmitting uplink control information in a wireless communication system, and more particularly, to a method and apparatus for efficiently transmitting uplink control information using beam information set to a terminal. It is about.

As an example of a wireless communication system to which the present invention can be applied, a 3GPP LTE (3rd Generation Partnership Project Long Term Evolution (LTE)) communication system will be described.

1 is a diagram schematically illustrating an E-UMTS network structure as an example of a wireless communication system. The Evolved Universal Mobile Telecommunications System (E-UMTS) system is an evolution from the existing Universal Mobile Telecommunications System (UMTS), and is currently undergoing basic standardization in 3GPP. In general, the E-UMTS may be referred to as a Long Term Evolution (LTE) system. For details of technical specifications of UMTS and E-UMTS, refer to Release 7 and Release 8 of the "3rd Generation Partnership Project; Technical Specification Group Radio Access Network", respectively.

Referring to FIG. 1, an E-UMTS is an access gateway (AG) located at an end of a user equipment (UE) and a base station (eNode B), an eNB, and a network (E-UTRAN) and connected to an external network. The base station may transmit multiple data streams simultaneously for broadcast service, multicast service and / or unicast service.

One or more cells exist in one base station. The cell is set to one of bandwidths such as 1.25, 2.5, 5, 10, 15, and 20 MHz to provide downlink or uplink transmission service to multiple terminals. Different cells may be configured to provide different bandwidths. The base station controls data transmission and reception for a plurality of terminals. For downlink (DL) data, the base station transmits downlink scheduling information to inform the corresponding UE of time / frequency domain, encoding, data size, and HARQ (Hybrid Automatic Repeat and reQuest) related information. In addition, the base station transmits uplink scheduling information to uplink UL data for uplink (UL) data and informs the corresponding time / frequency domain, encoding, data size, HARQ related information, and the like. An interface for transmitting user traffic or control traffic may be used between base stations. The core network (CN) may be composed of an AG and a network node for user registration of the terminal. The AG manages the mobility of the UE in units of a tracking area (TA) composed of a plurality of cells.

Wireless communication technology has been developed to LTE based on WCDMA, but the demands and expectations of users and operators are continuously increasing. In addition, as other radio access technologies continue to be developed, new technological evolution is required to be competitive in the future. Reduced cost per bit, increased service availability, the use of flexible frequency bands, simple structure and open interface, and adequate power consumption of the terminal are required.

The present invention provides a method and apparatus for transmitting uplink control information in a wireless communication system.

The technical problems to be achieved in the present invention are not limited to the technical problems mentioned above, and other technical problems not mentioned above will be clearly understood by those skilled in the art from the following description. Could be.

In a wireless communication system according to an embodiment of the present invention, a method for transmitting uplink control information by a terminal to a base station, the method comprising: setting beam information for at least one subframe; Transmitting first uplink control information on a subframe corresponding to the beam for the terminal based on the configured beam information; Counting a first timer corresponding to the type of the first uplink control information; And transmitting second uplink control information of the same type as the first uplink control information on a subframe corresponding to the beam for the terminal located at a time point after the counting of the first timer expires. It may include.

In this case, further comprising counting a second timer corresponding to the type of the first uplink control information together with the first timer, counting of the first timer expires, and counting the second timer. If so, the second uplink control information can be transmitted.

In addition, when a plurality of uplink control information having different types are to be transmitted on a subframe corresponding to the beam for the terminal, it may be selectively transmitted according to a preset priority.

In addition, when a plurality of uplink control information having different types are to be transmitted on a subframe corresponding to the beam for the terminal, the most recent generated uplink control information is included among the plurality of uplink control information. Can be selected.

The setting of the beam information may include receiving downlink control information including the beam information from the base station; And setting beam information on the at least one subframe based on the beam information detected from the downlink control information.

In addition, when the terminal is included in the terminal list included in the downlink control information, the terminal may transmit the first uplink control information.

In a wireless communication system according to an embodiment of the present invention, a terminal includes: an RF unit for transmitting and receiving a radio signal with a base station; And transmitting first uplink control information on a subframe corresponding to a beam for the terminal based on beam information configured for at least one subframe, connected to the RF unit, and performing the first uplink control. Counting a first timer corresponding to the information and positioned at a time point after the counting of the first timer expires, on a subframe corresponding to the beam for the terminal, a first type of the same type as the first uplink control information; 2 may include a processor for transmitting uplink control information.

In this case, when the second timer corresponding to the first uplink control information is counted together with the first timer, when the counting of the first timer expires and the second timer is counting, the second uplink control Information can be sent.

In addition, when a plurality of uplink control information having different types are to be transmitted on a subframe corresponding to the beam for the terminal, it may be selectively transmitted according to a preset priority.

In addition, when a plurality of uplink control information having different types are to be transmitted on a subframe corresponding to the beam for the terminal, the most recent generated uplink control information is included among the plurality of uplink control information. Can be selected.

The processor may receive downlink control information including the beam information from the base station through the RF module, and transmit the received downlink control information to the at least one subframe based on the beam information detected from the downlink control information. Beam information may be set.

In addition, when the terminal is included in the terminal list included in the downlink control information, the terminal may transmit the first uplink control information.

According to the present invention, even when the beam pattern changes with time, the UE can efficiently transmit the uplink control information.

The effects obtainable in the present invention are not limited to the above-mentioned effects, and other effects not mentioned above may be clearly understood by those skilled in the art from the following description. will be.

1 schematically illustrates an E-UMTS network structure as an example of a wireless communication system.

FIG. 2 is a diagram illustrating a control plane and a user plane structure of a radio interface protocol between a terminal and an E-UTRAN based on the 3GPP radio access network standard. FIG.

3 is a diagram for explaining a physical channel used in the 3GPP system and a general signal transmission method using the same.

4 is a diagram illustrating a structure of a radio frame used in an LTE system.

5 is a diagram illustrating a structure of a downlink radio frame used in the LTE system.

6 is a diagram illustrating a structure of an uplink subframe used in an LTE system.

7 shows examples of a connection scheme of a TXRU and an antenna element.

8 is an example of a self-contained subframe structure.

9 to 10 illustrate a method for transmitting uplink control information according to an embodiment of the present invention.

11 illustrates a block diagram of a communication device according to an embodiment of the present invention.

The construction, operation, and other features of the present invention will be readily understood by the embodiments of the present invention described with reference to the accompanying drawings. The embodiments described below are examples in which technical features of the present invention are applied to a 3GPP system.

Although the present specification describes an embodiment of the present invention using an LTE system and an LTE-A system, this as an example may be applied to any communication system corresponding to the above definition.

In addition, the specification of the base station may be used as a generic term including a remote radio head (RRH), an eNB, a transmission point (TP), a reception point (RP), a relay, and the like.

FIG. 2 is a diagram illustrating a control plane and a user plane structure of a radio interface protocol between a terminal and an E-UTRAN based on the 3GPP radio access network standard. The control plane refers to a path through which control messages used by a user equipment (UE) and a network to manage a call are transmitted. The user plane refers to a path through which data generated at an application layer, for example, voice data or Internet packet data, is transmitted.

The physical layer, which is the first layer, provides an information transfer service to an upper layer by using a physical channel. The physical layer is connected to the upper layer of the medium access control layer through a transport channel. Data moves between the medium access control layer and the physical layer through the transmission channel. Data moves between the physical layer between the transmitting side and the receiving side through the physical channel. The physical channel utilizes time and frequency as radio resources. In detail, the physical channel is modulated in an Orthogonal Frequency Division Multiple Access (OFDMA) scheme in downlink, and modulated in a Single Carrier Frequency Division Multiple Access (SC-FDMA) scheme in uplink.

The medium access control (MAC) layer of the second layer provides a service to a radio link control (RLC) layer, which is a higher layer, through a logical channel. The RLC layer of the second layer supports reliable data transmission. The function of the RLC layer may be implemented as a functional block inside the MAC. The Packet Data Convergence Protocol (PDCP) layer of the second layer performs a header compression function to reduce unnecessary control information in order to efficiently transmit IP packets such as IPv4 or IPv6 in a narrow bandwidth wireless interface.

The Radio Resource Control (RRC) layer located at the bottom of the third layer is defined only in the control plane. The RRC layer is responsible for controlling logical channels, transmission channels, and physical channels in connection with configuration, reconfiguration, and release of radio bearers. The radio bearer refers to a service provided by the second layer for data transmission between the terminal and the network. To this end, the RRC layers of the UE and the network exchange RRC messages with each other. If there is an RRC connected (RRC Connected) between the UE and the RRC layer of the network, the UE is in an RRC connected mode, otherwise it is in an RRC idle mode. The non-access stratum (NAS) layer above the RRC layer performs functions such as session management and mobility management.

The downlink transmission channel for transmitting data from the network to the UE includes a broadcast channel (BCH) for transmitting system information, a paging channel (PCH) for transmitting a paging message, and a downlink shared channel (SCH) for transmitting user traffic or a control message. have. Traffic or control messages of a downlink multicast or broadcast service may be transmitted through a downlink SCH or may be transmitted through a separate downlink multicast channel (MCH). The uplink transmission channel for transmitting data from the terminal to the network includes a random access channel (RAC) for transmitting an initial control message and an uplink shared channel (SCH) for transmitting user traffic or a control message. Above the transmission channel, the logical channel mapped to the transmission channel includes a broadcast control channel (BCCH), a paging control channel (PCCH), a common control channel (CCCH), a multicast control channel (MCCH), and an MTCH (multicast). Traffic Channel).

FIG. 3 is a diagram for explaining physical channels used in a 3GPP system and a general signal transmission method using the same.

When the UE is powered on or enters a new cell, the UE performs an initial cell search operation such as synchronizing with the base station (S301). To this end, the terminal may receive a Primary Synchronization Channel (P-SCH) and a Secondary Synchronization Channel (S-SCH) from the base station to synchronize with the base station and obtain information such as a cell ID. have. Thereafter, the terminal may receive a physical broadcast channel from the base station to obtain broadcast information in a cell. Meanwhile, the terminal may receive a downlink reference signal (DL RS) in the initial cell search step to check the downlink channel state.

Upon completion of the initial cell search, the UE acquires more specific system information by receiving a physical downlink control channel (PDSCH) according to a physical downlink control channel (PDCCH) and information on the PDCCH. It may be (S302).

On the other hand, when the first access to the base station or there is no radio resource for signal transmission, the terminal may perform a random access procedure (RACH) for the base station (steps S303 to S306). To this end, the UE may transmit a specific sequence as a preamble through a physical random access channel (PRACH) (S303 and S305), and receive a response message for the preamble through the PDCCH and the corresponding PDSCH ( S304 and S306). In the case of contention-based RACH, a contention resolution procedure may be additionally performed.

After performing the procedure as described above, the UE performs a PDCCH / PDSCH reception (S307) and a physical uplink shared channel (PUSCH) / physical uplink control channel (Physical Uplink) as a general uplink / downlink signal transmission procedure. Control Channel (PUCCH) transmission (S308) may be performed. In particular, the terminal receives downlink control information (DCI) through the PDCCH. Here, the DCI includes control information such as resource allocation information for the terminal, and the format is different according to the purpose of use.

Meanwhile, the control information transmitted by the terminal to the base station through the uplink or received by the terminal from the base station includes a downlink / uplink ACK / NACK signal, a channel quality indicator (CQI), a precoding matrix index (PMI), and a rank indicator (RI). ), And the like. In the 3GPP LTE system, the terminal may transmit the above-described control information such as CQI / PMI / RI through the PUSCH and / or PUCCH.

4 is a diagram illustrating a structure of a radio frame used in an LTE system.

Referring to FIG. 4, a radio frame has a length of 10 ms (327200 × T _s ) and is composed of 10 equally sized subframes. Each subframe has a length of 1 ms and consists of two slots. Each slot has a length of 0.5 ms (15360 x T _s ). Here, T _s represents a sampling time and is represented by Ts = 1 / (15 kHz x 2048) = 3.2552 x 10 ^-8 (about 33 ns). The slot includes a plurality of OFDM symbols in the time domain and a plurality of resource blocks (RBs) in the frequency domain. In the LTE system, one resource block includes 12 subcarriers x 7 (6) OFDM symbols. Transmission Time Interval (TTI), which is a unit time at which data is transmitted, may be determined in units of one or more subframes. The structure of the radio frame described above is merely an example, and the number of subframes included in the radio frame, the number of slots included in the subframe, and the number of OFDM symbols included in the slot may be variously changed.

FIG. 5 is a diagram illustrating a control channel included in a control region of one subframe in a downlink radio frame.

Referring to FIG. 5, a subframe consists of 14 OFDM symbols. According to the subframe configuration, the first 1 to 3 OFDM symbols are used as the control region and the remaining 13 to 11 OFDM symbols are used as the data region. In the drawings, R1 to R4 represent reference signals (RSs) or pilot signals for antennas 0 to 3. The RS is fixed in a constant pattern in a subframe regardless of the control region and the data region. The control channel is allocated to a resource to which no RS is allocated in the control region, and the traffic channel is also allocated to a resource to which no RS is allocated in the data region. Control channels allocated to the control region include PCFICH (Physical Control Format Indicator CHannel), PHICH (Physical Hybrid-ARQ Indicator CHannel), PDCCH (Physical Downlink Control CHannel).

The PCFICH is a physical control format indicator channel and informs the UE of the number of OFDM symbols used for the PDCCH in every subframe. The PCFICH is located in the first OFDM symbol and is set in preference to the PHICH and PDCCH. The PCFICH is composed of four Resource Element Groups (REGs), and each REG is distributed in a control region based on a Cell ID (Cell IDentity). One REG is composed of four resource elements (REs). The RE represents a minimum physical resource defined by one subcarrier x one OFDM symbol. The PCFICH value indicates a value of 1 to 3 or 2 to 4 depending on the bandwidth and is modulated by Quadrature Phase Shift Keying (QPSK).

The PHICH is a physical hybrid automatic repeat and request (HARQ) indicator channel and is used to carry HARQ ACK / NACK for uplink transmission. That is, the PHICH indicates a channel through which DL ACK / NACK information for UL HARQ is transmitted. The PHICH consists of one REG and is scrambled cell-specifically. ACK / NACK is indicated by 1 bit and modulated by binary phase shift keying (BPSK). The modulated ACK / NACK is spread with Spreading Factor (SF) = 2 or 4. A plurality of PHICHs mapped to the same resource constitutes a PHICH group. The number of PHICHs multiplexed into the PHICH group is determined according to the number of spreading codes. The PHICH (group) is repeated three times to obtain diversity gain in the frequency domain and / or the time domain.

The PDCCH is a physical downlink control channel and is allocated to the first n OFDM symbols of a subframe. Here, n is indicated by the PCFICH as an integer of 1 or more. The PDCCH consists of one or more CCEs. The PDCCH informs each UE or UE group of information related to resource allocation of a paging channel (PCH) and a downlink-shared channel (DL-SCH), an uplink scheduling grant, and HARQ information. Paging channel (PCH) and downlink-shared channel (DL-SCH) are transmitted on the PDSCH. Accordingly, the base station and the terminal generally transmit and receive data through the PDSCH except for specific control information or specific service data.

Data of the PDSCH is transmitted to which UE (one or a plurality of UEs), and information on how the UEs should receive and decode PDSCH data is included in the PDCCH and transmitted. For example, a specific PDCCH is CRC masked with a Radio Network Temporary Identity (RNTI) of "A", a radio resource (eg, frequency location) of "B" and a DCI format of "C", that is, a transmission format. Assume that information about data transmitted using information (eg, transmission block size, modulation scheme, coding information, etc.) is transmitted through a specific subframe. In this case, the terminal in the cell monitors, that is, blindly decodes, the PDCCH in the search region by using the RNTI information of the cell, and if there is at least one terminal having an "A" RNTI, the terminals receive and receive the PDCCH. The PDSCH indicated by "B" and "C" is received through the information of one PDCCH.

6 is a diagram illustrating a structure of an uplink subframe used in an LTE system.

Referring to FIG. 6, an uplink subframe may be divided into a region to which a Physical Uplink Control CHannel (PUCCH) carrying control information is allocated and a region to which a Physical Uplink Shared CHannel (PUSCH) carrying user data is allocated. The middle part of the subframe is allocated to the PUSCH, and both parts of the data area are allocated to the PUCCH in the frequency domain. The control information transmitted on the PUCCH includes ACK / NACK used for HARQ, Channel Quality Indicator (CQI) indicating a downlink channel state, RI (Rank Indicator) for MIMO, and scheduling request (SR), which is an uplink resource allocation request. There is this. The PUCCH for one UE uses one resource block occupying a different frequency in each slot in a subframe. That is, two resource blocks allocated to the PUCCH are frequency hoped at the slot boundary. In particular, FIG. 6 illustrates that PUCCH having m = 0, PUCCH having m = 1, PUCCH having m = 2, and PUCCH having m = 3 are allocated to a subframe.

Hereinafter, channel state information (CSI) reporting will be described. In the current LTE standard, there are two transmission schemes, an open-loop MIMO operated without channel state information and a closed-loop MIMO operated based on channel state information. In particular, in a closed loop MIMO, each of the base station and the terminal may perform beamforming based on channel state information in order to obtain a multiplexing gain (multiplexing gain) of the MIMO antenna. The base station instructs the terminal to feed back the channel state information (CSI) for the downlink signal by assigning a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH) to the terminal.

CSI is largely classified into three types of information such as rank indicator (RI), precoding matrix index (PMI), and channel quality indication (CQI). First, as described above, RI represents rank information of a channel, and means the number of streams that a UE can receive through the same frequency-time resource. In addition, since the RI is determined by the long term fading of the channel, the RI is fed back to the base station at a longer period than the PMI and CQI values.

Secondly, PMI is a value reflecting spatial characteristics of a channel and represents a precoding matrix index of a base station preferred by a terminal based on a metric such as SINR. Finally, CQI is a value representing the strength of the channel, which means the reception SINR that can be obtained when the base station uses PMI.

In the 3GPP LTE-A system, the base station may configure a plurality of CSI processes to the UE, and receive and report the CSI for each CSI process. Here, the CSI process is composed of a CSI-RS resource for signal quality specification from a base station and an interference measurement (CSI-IM) resource for interference measurement, that is, an IMR (interference measurement resource).

In millimeter wave (mmW), the wavelength is shortened, allowing the installation of multiple antenna elements in the same area. Specifically, in the 30 GHz band, the wavelength is 1 cm, and a total of 64 (8x8) antenna elements in a 2D (dimension) array form at 0.5 lambda intervals can be installed in a panel of 4 by 4 cm. Therefore, recent trends in the mmW field have attempted to increase the coverage or increase the throughput by increasing the beamforming gain using a plurality of antenna elements.

In this case, if a TXRU (Transceiver Unit) is provided to enable transmission power and phase adjustment for each antenna element, independent beamforming is possible for each frequency resource. However, in order to install TXRU in all 100 antenna elements, there is a problem in terms of cost effectiveness. Therefore, a method of mapping a plurality of antenna elements to one TXRU and adjusting the direction of the beam by an analog phase shifter is considered. The analog beamforming method has a disadvantage in that only one beam direction can be made in the entire band and thus frequency selective beamforming cannot be performed.

A hybrid BF having B TXRUs, which is smaller than Q antenna elements, may be considered as an intermediate form between digital BF and analog BF. In this case, although there are differences depending on the connection scheme of the B TXRU and the Q antenna elements, the beam directions that can be simultaneously transmitted are limited to B or less.

7 shows examples of a connection scheme of a TXRU and an antenna element.

7 (a) shows how a TXRU is connected to a sub-array. In this case the antenna element is connected to only one TXRU. In contrast, FIG. 7B shows how the TXRU is connected to all antenna elements. In this case the antenna element is connected to all TXRUs. In Fig. 7, W denotes a phase vector multiplied by an analog phase shifter. That is, the direction of analog beamforming is determined by W. Here, the mapping between the CSI-RS antenna port and the TXRUs may be 1-to-1 or 1-to-multi.

As more communication devices demand larger communication capacities, there is a need for improved wireless broadband communication compared to existing radio access technology (RAT). In addition, Massive MTC (Machine Type Communications), which connects multiple devices and objects to provide various services anytime and anywhere, is also one of the major issues to be considered in next-generation communication. In addition, communication system design considering services / UEs that are sensitive to reliability and latency has been discussed. The introduction of the next-generation RAT in consideration of this point is discussed, and in the present invention referred to as NewRAT for convenience.

In order to minimize data transmission latency in the TDD system, the fifth generation NewRAT considers a self-contained subframe structure as shown in FIG. 8. 8 is an example of a self-contained subframe structure.

In FIG. 8, the hatched region represents a downlink control region, and the black portion represents an uplink control region. An area without an indication may be used for downlink data transmission or may be used for uplink data transmission. The feature of such a structure is that downlink transmission and uplink transmission are sequentially performed in one subframe, thereby transmitting downlink data and receiving uplink ACK / NACK in the subframe. As a result, when a data transmission error occurs, the time taken to retransmit data is reduced, thereby minimizing the latency of the final data transfer.

In this self-contained subframe structure, a time gap is required for a base station and a UE to switch from a transmission mode to a reception mode or a process of switching from a reception mode to a transmission mode. To this end, some OFDM symbols (OFDM symbols; OS) at the time of switching from downlink to uplink in a self-contained subframe structure are set to a guard period (GP).

As an example of the self-contained subframe type configurable / configurable in a system operating based on NewRAT, at least the following four subframe types may be considered.

Downlink Control Section + Downlink Data Section + GP + Uplink Control Section

Downlink control section + downlink data section

Downlink Control Section + GP + Uplink Data Section + Uplink Control Section

Downlink control section + GP + uplink data section

Meanwhile, in the fifth generation NewRAT, a situation in which sharp beamforming (for example, analog beamforming) for DL / UL is introduced using a plurality of antennas may be considered. In this case, sharp beamforming may change over time. You can assume that.

For example, a situation in which the beam direction in SF # n (ie, subframe # n) and the beam direction in SF # m (ie, subframe # m) may be different may be common, and transmission and reception in different beam directions may be common. The signal may be assumed to be a level at which the effects of signal attenuation and the like are almost ignored. In such a situation, when transmitting an uplink signal, terminals suitable for the beam direction A may be appropriate to transmit a signal at a point corresponding to the beam direction A. Here, the meaning of A suited to the beam direction may mean a situation in which transmission efficiency in the corresponding direction is high, a probability of receiving or detecting a signal at a base station side, or a reception strength of the signal is high.

Therefore, when the terminals suitable for the beam direction A transmit a signal at a time corresponding to the direction B, the base station cannot receive or detect the signal transmitted by the terminal or the received power intensity of the signal drops below a certain level. Can be.

In addition, in the fifth generation NewRAT, a form consisting of a downlink transmission part, a GP, and an uplink transmission part within a reference time unit, such as a subframe unit, may be considered. In this case, the time interval over which a physical channel (hereinafter, referred to as xPUCCH) for uplink control information (UCI) transmission is transmitted may be very limited, for example, 1 or 2 symbols.

In addition, the beam direction indicated by beam pattern, beam information, or beam reference signal identification (BRS ID) may be changed for each reference time unit (for example, a single or a plurality of subframes), and the base station may A proper terminal can be scheduled according to the assumed or used beam information. In this case, the terminal may transmit / receive data or a reference signal with the base station in a subframe in which proper beam information is assumed by detecting downlink control information (DCI).

On the other hand, in this case, the unscheduled terminal cannot know whether the beam information assumption for a particular subframe is appropriate or unsuitable for the unscheduled terminal. Here, the meaning that the beam information hypothesis is suitable for which terminal may indicate whether the transmission and reception of data in a specific subframe is possible or whether the beam information hypothesis is the same as the beam information set in the terminal by the beam information hypothesis. .

As described above, in the case of the UE that has not been scheduled, the UCI transmission based on periodic reporting may not be suitable since the proper beam pattern may not be guaranteed for each transmission period, and the triggering based UCI transmission may not be suitable. Is the next best option. However, in the case of triggering based UCI transmission scheme, the DCI overhead may be excessively increased. Therefore, it is necessary to consider a more efficient UCI transmission scheme.

Accordingly, the present invention is to propose a method for efficiently transmitting the UCI based on the beam information in order to solve the above problems. The expressions used in the embodiments of the present invention are not limited to the LTE system, and it is obvious that the present invention can be extended to physical channels or UCI contents named by different RATs or other names. In addition, the assumption about the analog beam is also not limited to either the single or plural cases at a particular point in time, and is applicable to all.

<Example 1: UE group specific UCI or beam specific UCI triggering>

Types of UCI may include beam state information (BSI), beam refinement information (BRI), channel state information (CSI), scheduling request (SR), and HARQ-ACK. Here, the CSI-related UCI is called explicit CSI and may be set to a value extracted from a channel coefficient.

Meanwhile, according to Embodiment 1 of the present invention, a UE group may be generated through preset or higher layer signaling, and the base station may transmit DCI to the UE for each UE group. At this time, the DCI may be set according to the terminal group ID corresponding to the DCI CRC masking or scrambling (Scrambling). For example, terminals belonging to the same terminal group may receive the same beam information or beam information group. However, it is also acceptable for terminals having the same beam information to be configured in different terminal groups. Basically, the terminal group may be preset or information about its configuration may be set through a higher layer.

If the terminal group is composed of terminals corresponding to the same beam information, the terminal group ID may be replaced with a beam-specific indication such as a BRS ID. In this case, there may be no separate signaling for UE grouping.

Meanwhile, as another example, a case in which terminals constituting one terminal group correspond to different beam information may be considered. In this case, when the UCI triggering DCI (UCI triggering DCI) is transmitted, the UCI triggering DCI transmission time The beam information assumed or used by the subframe corresponding to may be included in the UCI triggering DCI and transmitted to the terminal. In this case, the terminal may transmit the UCI only when the received beam information is set to be suitable for the terminal.

DCI detectable by a specific UE group includes a field value indicating whether UCI is transmitted, a field value indicating UCI type, a field value indicating information on timing of UCI transmission, and a reference for measuring CSI related information. It may include information about a reference resource or channel information on which a UCI is to be transmitted. In this case, the channel information to which the UCI is transmitted may include information on whether to transmit the UCI to PUCCH or PUSCH, or may include a TPC (Transmit Power Control) value for the channel or resource information on the channel.

In general, when performing group triggering in consideration of DCI overhead, it may be inefficient to separate DCI for each UCI type or UCI set, and for single UCI triggering for each UE group, beam information, or beam pattern regardless of the UCI type. It may be better to use DCI. In this case, the UE allows simultaneous transmission of at least CSI-related information in consideration of the correlation and time-varying degree among the information on the UCI type, and may simultaneously select and transmit one or more of BSI / BRI / CSI. That is, the terminal selectively transmits one or more of BSI / BRI / CSI, and when two or more information are selected, the terminal may simultaneously transmit on one subframe.

On the other hand, in case of SR, in order to reduce DCI overhead, the SR may be independently selected together with CSI-related information. That is, one or more of BSI / BRI / CSI / SR may be selected to transmit selected information simultaneously, and the unselected information may be transmitted independently of the selected information. On the other hand, by determining the SR as a separate UCI from the CSI-related information, it may be determined whether to transmit separately from the CSI-related information.

For example, the SR may be considered as a separate UCI type according to the SR transmission purpose such as a UL grant request, a BRRS request, a beam change request, and a beam change request. That is, in the case of SR, when indicating the type of UCI, there may exist a plurality of UCI types according to the purpose of transmitting the SR. The information on the reference resource for measuring the CSI-related information may include information on a process or a resource on which a CSI-RS or BRRS is transmitted, such as information on a symbol index.

On the other hand, when the base station transmits the UCI triggering DCI for a specific terminal group, terminals that are not suitable for the beam assumed or used in the subframe at that time will be unlikely to receive the DCI, and assumed in the subframe at that time. Or terminals suitable for the beam to be used or receive the DCI. In addition, terminals capable of detecting DCI may be limited to a specific terminal group according to a masking / scrambling technique.

In this case, after receiving the DCI transmitted by the base station, terminals successfully detected or decoded may prepare for UCI transmission such as measuring CSI related information based on the UCI triggering related information included in the received DCI. After the UCI transmission preparation is completed, the transmission ready UCI may be transmitted using a predetermined physical channel at a predetermined time point.

Meanwhile, the DCI transmitted by the base station may include information on the terminal list. In this case, the terminal may transmit only the UEs set in the terminal list of the DCI among the terminals that receive or decode the DCI by receiving the DCI. That is, depending on whether UCI transmission is set in DCI, operations of UEs that detect or decode DCI may vary.

In addition, the terminal and the base station may assume that a beam suitable for the terminal group is used at a specific time. In this case, the DCI may include resource allocation information for the physical channel, and there is an advantage in that a resource may be flexibly selected according to the resource allocation information. However, on the other hand, as the number of terminals constituting the terminal group increases, DCI overhead may be excessive. If the DCI is set to a beam specific DCI, the beam set by the DCI It may not be possible to specify a suitable terminal.

Therefore, at least the information on the physical channel for transmitting the UCI, such as resource allocation information, it may be better to set for each terminal in the upper layer. For example, the UCI triggering DCI may be separately set through an upper layer depending on whether UCI is transmitted on PUCCH or PUSCH. In other words, only when the UCI is transmitted through the PUCCH, information on a physical channel for transmitting the UCI may be set for each UE through an upper layer. In this case, the information on the physical channel for transmitting the UCI may include resource allocation information.

Meanwhile, in another method, a field value indicating whether UCI is transmitted, a field value indicating UCI type, a field value indicating information on timing of transmitting UCI, and reference resource for measuring CSI related information DCI including information about the channel information, or the channel information to be transmitted UCI may be configured to be UE-specific (UE-specific). That is, each terminal may independently receive a DCI for PDSCH scheduling or PUSCH scheduling and a DCI for UCI triggering. To this end, DCIs for different purposes may perform CRC masking or scrambling with the same RNTI among UE RNTI or C-RNTI, and may set or determine a DCI type or form through a flag field in the DCI. However, in addition to the UE RNTI and the C-RNTI, a third RNTI may be used separately from the scheduling purpose.

Meanwhile, among the information included in the DCI, the channel information to which the UCI is transmitted includes information on whether to transmit the UCI to the PUCCH and the PUSCH, as described above, or a TPC (Transmit Power Control) value for the channel or Resource information for the channel.

<Example 2: Beam specific information based UCI transmission>

The base station may change beam information such as a BRS ID and a transmission / reception beam pattern (Tx / Rx beam pattern) for each reference time unit, and may signal the beam information to a plurality of terminals in common or beam-specifically. In this case, the aforementioned reference time unit may be one subframe or a plurality of subframes defined in advance or set by an upper layer.

In detail, the change of the beam information may use a specific DCI format. That is, the DCI may perform CRC masking or scrambling using a third RNTI such as Beam-RNTI to be received by a plurality of terminals, and perform CRC masking or scrambling using beam information such as BRS ID. It may be. In this case, the DCI may be a beam indication DCI (Beam indication DCI) transmitted in each subframe or transmitted at a predetermined period, the beam indication DCI includes information about the beam, such as including a field indicating the BRS ID can do.

The specific terminals receiving the DCI transmitted according to a specific period may succeed in detecting the DCI when the beam information included in the DCI is beam information suitable for the specific terminal. Here, the specific period may be every subframe or may be a period set in advance or set by an upper layer.

However, even when CRC masking or scrambling is performed using an RNTI value not associated with a beam, UEs whose beam information used or assumed in a subframe corresponding to a corresponding time point do not correspond to the optimal beam information may also be used. The DCI including the information may be detected, and beam information used or assumed in a subframe corresponding to the corresponding time point may be obtained.

On the other hand, when configuring the RNTI with information related to the beam, the beam information used or assumed at the time when the DCI is transmitted may indicate an optimal beam, or only predetermined terminals may be configured to detect the DCI.

Basically, physical channel information for transmitting UCI such as CSI / BRI / BSI / SR may be set in an upper layer. For example, a PUCCH resource index may correspond to physical channel information. In this case, the PUCCH index may be set not to overlap each terminal. In this case, the PUCCH overhead may increase according to the number of terminals located in the serving cell. Therefore, as a method for alleviating this, it is possible to allow the PUCCH resource index to be the same between terminals where different beams are used or assumed in PUCCH transmission. Specifically, when configuring the setting for UCI transmission for each terminal, it is possible to configure the PUCCH resource index and beam information together.

In addition, the SR may be set to a separate UCI type according to a transmission purpose of the SR, such as a UL grant request, a BRRS request, a beam change request, and the like. In this case, the SR may exist in a plurality of UCI types according to each purpose, and the reporting configuration may be independently set or configured.

Upon successfully receiving the DCI including the beam information, the UE may determine whether to transmit UCI using the PUCCH based on the obtained beam information.

This will be described in detail with reference to FIG. 9. FIG. 9 illustrates an embodiment in which UCI # 1 and UCI # 2 are transmitted based on independent Prohibit Timers for a UE having optimal beam information as beam #A. In this case, the circle in FIG. 9 indicates the time point at which UCI # 1 is transmitted, and the rhombus indicates the time point at which UCI # 2 is transmitted.

In addition, the solid arrow indicates the Prohibit Timer for UCI # 1, and the dotted line arrow indicates the Prohibit Timer for UCI # 2.

Referring now to an embodiment of the present invention with reference to FIG. 9, when the beam #A is being used or assumed in a specific subframe, and the UCI transmission configuration for the UE # 1 is beam #A, the specific sub In the frame, it may be configured to transmit the UCI using the PUCCH resource set in the upper layer. If the set beams are different from each other, that is, when the beam for the UE # 1 is not the beam # A in a specific subframe or the UE does not receive the beam information related DCI, the UE may not transmit the UCI. .

On the other hand, depending on the UCI type and update period, even if the beam suitable for the terminal is used or assumed continuously, it may not be necessary to continuously send UCI, in this case, to set the Prohibit Timer for the UCI, or Prohibit Timer for each UCI type Can be set For example, the BSI and the CSI may have different Prohibit Timers, and may not transmit the corresponding UCI even when a proper beam turn returns to the corresponding terminal until the Prohibit Timer expires. For example, after the BSI is transmitted once, even if the proper beam turn returns to the UE, the BSI may not be transmitted again until the Prohibit Timer for the BSI expires.

In this case, the specific UCI set may be transmitted sequentially without considering simultaneous transmission. That is, BSI, BRI, and CSI may be sequentially transmitted. In this case, the Prohibit Timer of the BSI may be set longer than that of the CSI. When the two Prohibit Timers expire, a specific UCI may be selectively transmitted according to a specific priority at the next transmittable time. For example, if the priority of the BSI is higher than the priority of the CSI, only the BSI may be selected and transmitted. The Prohibit Timer described above may operate independently, but when the Prohibit Timer having a high priority or a high start value expires, other Prohibit Timers may also expire.

In the above-described example, in case of SR, it may have a separate Prohibit Timer. In more detail, an SR and another UCI may be configured through an upper layer to allow simultaneous transmission.

On the other hand, if the UE does not receive or detect the beam indication DCI (Beam Indication DCI) in the above-described multiple UCI (Multiple UCI) transmission scheme may cause ambiguity about the UCI transmission between the terminal and the base station. That is, when transmitting a plurality of types of UCI, if the terminal does not receive or detect the beam indication DCI, ambiguity about UCI transmission may occur between the terminal and the base station.

Accordingly, there may be an Expiration Timer in addition to the Prohibit Timer. For example, if the Prohibit Timer for a wideband CQI has expired but the Expiration Timer for a wideband CQI has not expired, the DCI will return to the DCI after the Prohibit Timer expires, that is, after the Prohibit Timer expires. A wideband CQI may be transmitted at a point where the included beam information coincides with a suitable beam of the terminal. On the other hand, when both the Prohibit Timer and the Expiration Timer expire, the transmission of the corresponding wideband CQI can be omitted.

Now, with reference to FIG. 10, another embodiment for transmitting the UCI will be described. The embodiment shown in FIG. 10 relates to setting a timing set for each UCI type. In this case, the timing set may be set in advance or may be set through higher layer signaling. For example, reference timing may be set for the wideband CQI and the subband CQI, respectively. In this case, the reference timing corresponds to the hatched portion in FIG. 10.

The terminal includes the reference timing based on the closest reference timing among the previous reference timings including the current reference time or the closest reference timing in the subframe corresponding to the current time according to the beam indication DCI received from the base station. The UCI type may be transmitted on the nearest suitable beam sequence.

On the other hand, the timing set may be in the form of an allowed time window. In this case, the allowed time window may be defined as a predetermined period and an offset for each UCI or each UCI type, and may be preset or designated through higher layer signaling.

If the UE is using beam information suitable for the UE within a specific time window, and the UE detects the beam indication DCI, the UE may transmit the UCI at that time. For example, when beam information suitable for a UE is detected in a plurality of subframes corresponding to the allowed time window, UCI is transmitted in a specific subframe or UCI is transmitted in all of a plurality of subframes in which suitable beam information is detected. Can transmit In this case, the specific subframe may be the most advanced subframe among the plurality of subframes in which suitable beam information is detected.

On the other hand, when the allowed time windows overlap between different UCI types, all of the corresponding UCIs may be transmitted, or a specific UCI may be selected and transmitted according to a priority rule. In this case, the priority rule, that is, which UCI to select may be set through an upper layer. For example, the priority rule may be determined according to the UCI type and may be determined according to the order between allowed time windows. That is, in order to transmit the latest information, the UCI corresponding to the allowed time window following in time may be set to have a high priority.

Alternatively, in consideration of the situation when the UE transmits the UCI, an appropriate UCI type may be selected. In this case, in order to prevent ambiguity, when transmitting the UCI, information about the UCI type may be included in the PUCCH and transmitted. . The base station may divide the received UCI based on the information on the UCI type and the beam information included in the PUCCH.

On the other hand, according to the subframe configuration or the UCI type, UCI transmission may be possible in the PUCCH of the same subframe as the subframe in which the beam indication DCI is detected. However, when preparation for generating UCI is necessary, such as BSI / BRI / CSI measurement, transmission in the same subframe as the subframe in which the beam indication DCI is detected may be difficult. That is, in case of SR, UCI can be transmitted in the same subframe as the subframe at which the beam indication DCI is detected. However, if the UCI cannot be transmitted in the same subframe as the subframe at the time of detecting the beam indication DCI due to the UCI preparation process or the like, such as CSI measurement, a method for transmitting the UCI in the subframe after the subframe is provided. need.

To this end, when the UCI is transmitted in a subframe after the point of time when the beam indication DCI is detected, the beam indication DCI may further include beam information in the subframe after the point of time when the beam indication DCI is detected. For example, the beam directing DCI is used to provide information on the timing of the subframe, that is, the timing at which the same beam information as the beam information is used or assumed together with the beam information used or assumed in the subframe at which the beam directing DCI is detected. It may include.

The timing may be a timing at which HARQ-ACK is transmitted after a PDSCH is transmitted in a subframe in which a beam indication DCI is detected, or a PUSCH is transmitted after a UL grant PDCCH is transmitted in a subframe in which the beam indication DCI is detected. The timing may be.

Meanwhile, as the third timing, the UE measures the UCI in the subframe in which the beam indication DCI is detected, and then transmits the UCI at the indicated timing in consideration of the Prohibit Timer or the reference timing set. In this case, the Prohibit Timer may have a non-zero value, and before the Prohibit Timer expires, the subframe in which the beam information corresponding to each UE is used, that is, each UE is UCI in a subframe in which a beam suitable for each UE is used. Can be measured. At this time, the terminal can recognize the subframe using the beam suitable for each terminal through the beam indication DCI.

In addition, the UE may omit the UCI measurement when there is a time left above a certain level from the point in time to the expiration of the Prohibit Timer or when the time from a specific reference timing set to the next reference timing set remains above a certain level. It may be. In this case, the specific time point may be a time point at which the terminal receives the beam indication DCI.

When the Prohibit Timer expires, the UE may prepare for transmission of the UCI or start measurement of the UCI, and according to beam information, the UE may transmit the UCI prepared for transmission, that is, triggered UCI, even when the UE is transmitted. UCI measurement process for transmission can be performed.

Embodiments according to the present invention described above may be periodically transmitted, such as semi-persistent scheduling (SPS) or periodic sounding reference signal (SRS) transmission, in addition to a beam indication DCI or a signaling-based UCI transmission scheme corresponding thereto. For example, it is also possible to apply a deterministic method to the method of transmitting close to the periodic transmission.

Referring to FIG. 11, the communication device 1100 includes a processor 1110, a memory 1120, an RF module 1130, a display module 1140, and a user interface module 1150.

The communication device 1100 is illustrated for convenience of description and some modules may be omitted. In addition, the communication device 1100 may further include necessary modules. In addition, some modules in the communication device 1100 may be classified into more granular modules. The processor 1110 is configured to perform an operation according to the embodiment of the present invention illustrated with reference to the drawings. In detail, the detailed operation of the processor 1110 may refer to the contents described with reference to FIGS. 1 to 10.

The memory 1120 is connected to the processor 1110 and stores an operating system, an application, program code, data, and the like. The RF module 1130 is connected to the processor 1110 and performs a function of converting a baseband signal into a radio signal or converting a radio signal into a baseband signal. To this end, the RF module 1130 performs analog conversion, amplification, filtering and frequency up-conversion, or a reverse process thereof. The display module 1140 is connected to the processor 1110 and displays various information. The display module 1140 may use well-known elements such as, but not limited to, a liquid crystal display (LCD), a light emitting diode (LED), and an organic light emitting diode (OLED). The user interface module 1150 is connected to the processor 1110 and may be configured with a combination of well-known user interfaces such as a keypad and a touch screen.

The embodiments described above are the components and features of the present invention are combined in a predetermined form. Each component or feature is to be considered optional unless stated otherwise. Each component or feature may be embodied in a form that is not combined with other components or features. It is also possible to combine some of the components and / or features to form an embodiment of the invention. The order of the operations described in the embodiments of the present invention may be changed. Some components or features of one embodiment may be included in another embodiment or may be replaced with corresponding components or features of another embodiment. It is obvious that the claims may be combined to form an embodiment by combining claims that do not have an explicit citation relationship in the claims or as new claims by post-application correction.

Certain operations described in this document as being performed by a base station may in some cases be performed by an upper node thereof. That is, it is obvious that various operations performed for communication with the terminal in a network including a plurality of network nodes including a base station may be performed by the base station or other network nodes other than the base station. A base station may be replaced by terms such as a fixed station, a Node B, an eNode B (eNB), an access point, and the like.

Embodiments according to the present invention may be implemented by various means, for example, hardware, firmware, software, or a combination thereof. In the case of a hardware implementation, an embodiment of the present invention may include one or more application specific integrated circuits (ASICs), digital signal processors (DSPs), digital signal processing devices (DSPDs), programmable logic devices (PLDs), FPGAs ( field programmable gate arrays), processors, controllers, microcontrollers, microprocessors, and the like.

In the case of implementation by firmware or software, an embodiment of the present invention may be implemented in the form of a module, procedure, function, etc. that performs the functions or operations described above. The software code may be stored in a memory unit and driven by a processor. The memory unit may be located inside or outside the processor, and may exchange data with the processor by various known means.

It will be apparent to those skilled in the art that the present invention may be embodied in other specific forms without departing from the spirit of the invention. Accordingly, the above detailed description should not be construed as limiting in all aspects and should be considered as illustrative. The scope of the invention should be determined by reasonable interpretation of the appended claims, and all changes within the equivalent scope of the invention are included in the scope of the invention.

The method and apparatus for transmitting uplink control information in the wireless communication system as described above have been described with reference to the example applied to the 3GPP LTE system, but it is possible to apply to various wireless communication systems in addition to the 3GPP LTE system.

Claims (12)

1. In a wireless communication system, in a terminal for transmitting uplink control information to a base station,

   Setting beam information for at least one subframe;

   Transmitting first uplink control information on a subframe corresponding to the beam for the terminal based on the configured beam information;

   Counting a first timer corresponding to the type of the first uplink control information; And

   Transmitting second uplink control information of the same type as the first uplink control information on a subframe corresponding to the beam for the terminal located at a time after the counting of the first timer expires. doing,

   Uplink control information transmission method.
2. The method of claim 1,

   Counting a second timer corresponding to the type of the first uplink control information together with the first timer,

   When the counting of the first timer expires and the second timer is counting, transmitting the second uplink control information;

   Uplink control information transmission method.
3. The method of claim 1,

   When a plurality of uplink control information having different types are to be transmitted on a subframe corresponding to the beam for the terminal, selectively transmitted according to a preset priority,

   Uplink control information transmission method.
4. The method of claim 1,

   When a plurality of uplink control information having different types are to be transmitted on a subframe corresponding to the beam for the terminal, the most recently generated uplink control information is selected from the plurality of uplink control information. ,

   Uplink control information transmission method.
5. The method of claim 1,

   Setting the beam information,

   Receiving downlink control information, including the beam information, from the base station;

   Setting beam information for the at least one subframe based on the beam information detected from the downlink control information;

   Uplink control information transmission method.
6. The method of claim 5, wherein

   When the terminal is included in the terminal list included in the downlink control information, the terminal transmits the first uplink control information,

   Uplink control information transmission method.
7. In a terminal in a wireless communication system,

   RF unit for transmitting and receiving radio signals with the base station; And

   The first uplink control information is connected to the RF unit and transmits first uplink control information on a subframe corresponding to a beam for the terminal based on beam information configured for at least one subframe. A second type of the same type as the first uplink control information, on a subframe corresponding to the beam for the terminal, counting a first timer corresponding to and positioned at a time after the counting of the first timer expires; Including a processor for transmitting uplink control information,

   Terminal.
8. The method of claim 7, wherein

   The second timer corresponding to the first uplink control information is counted together with the first timer. When the counting of the first timer expires and the second timer is counting, the second uplink control information is transmitted. doing,

   Terminal.
9. The method of claim 7, wherein

   When a plurality of uplink control information having different types are to be transmitted on a subframe corresponding to the beam for the terminal, selectively transmitted according to a preset priority,

   Terminal.
10. The method of claim 7, wherein

    When a plurality of uplink control information having different types are to be transmitted on a subframe corresponding to the beam for the terminal, the most recently generated uplink control information is selected from the plurality of uplink control information. ,

    Terminal.
11. The method of claim 7, wherein

    The processor,

    Receiving downlink control information including the beam information from the base station through the RF module, to set the beam information for the at least one subframe based on the beam information detected from the downlink control information ,

    Terminal.
12. The method of claim 11,

    When the terminal is included in the terminal list included in the downlink control information, the terminal transmits the first uplink control information,

    Terminal.

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