Method performed by terminal or base station in wireless communication system, and device therefor

Abstract

A method performed by a terminal according to at least one of embodiments disclosed in the present specification may comprise: receiving a sounding reference signal (SRS) configuration via higher layer signaling; performing, on the basis of the SRS configuration, SRS resource mapping for multiple SRS antenna ports; and transmitting an SRS through the multiple SRS antenna ports on the basis of the SRS resource mapping, wherein on the basis that the number of the multiple SRS antenna ports is three, the terminal performs the SRS resource mapping on the basis of an SRS resource mapping method defined for four SRS antenna ports, wherein the transmission of the SRS is performed by muting the last SRS port among the four SRS antenna ports.

Description

Method performed by a terminal or base station in a wireless communication system and device therefor

[0001] The present disclosure relates to a wireless communication system, and more particularly, to a method for transmitting and receiving uplink / downlink signals by a terminal or a base station in a wireless communication system, and a device therefor.

[0002] Wireless communication systems are widely deployed to provide various types of communication services, such as voice and data. Typically, wireless communication systems are multiple access systems that support communication with multiple users by sharing available system resources (e.g., bandwidth, transmission power). Examples of multiple access systems include code division multiple access (CDMA), frequency division multiple access (FDMA), time division multiple access (TDMA), orthogonal frequency division multiple access (OFDMA), and single-carrier frequency division multiple access (SC-FDMA).

[0003] NR Rel.15~17 supported 1, 2, 4-Tx port UL transmission, and NR Rel.18 introduced 8-Tx port UL transmission.

[0004] The technical task to be achieved is to provide a method and device for more accurately and efficiently performing the process of transmitting and receiving wireless signals. According to one embodiment, a method for transmitting and receiving uplink signals based on a 3-TX port and a terminal / base station for the same can be provided.

[0005] Other technical challenges can be inferred from the description below.

[0006] A method performed by a terminal according to one aspect of the present disclosure includes receiving a sounding reference signal (SRS) configuration through upper layer signaling; performing SRS resource mapping for a plurality of SRS antenna ports based on the SRS configuration; and transmitting an SRS through the plurality of SRS antenna ports based on the SRS resource mapping, wherein, based on the number of the plurality of SRS antenna ports being 3, the terminal: performs the SRS resource mapping based on an SRS resource mapping scheme defined for four SRS antenna ports, and performs the SRS transmission by muting a last SRS port among the four SRS antenna ports.

[0007] The above terminal can receive DCI (downlink control information) instructing to transmit the SRS through three SRS antenna ports.

[0008] The above terminal can transmit a PUSCH (physical uplink control channel) based on a non-coherent codebook supporting three antenna ports.

[0009] For example, the non-coherent codebook may include precoding matrices constructed based on Table A for each rank.

[0010] [Table A]

[0011]

[0012] The precoding matrices in Table A above can be normalized to 1 / √3.

[0013] For example, the non-coherent codebook may include precoding matrices constructed based on Table B for each rank.

[0014] [Table B]

[0015]

[0016] The x, y and z values ​​in Table B above may be variables given through network signaling.

[0017] The above network signaling includes a 2-bit index, and the 2-bit index can indicate the x, y, and z values ​​based on Table C.

[0018] [Table C]

[0019]

[0020] One of the three antenna ports for the above PUSCH can be set as a reference antenna port.

[0021] The above network signaling may indicate the x, y and z values ​​based on the reference antenna port.

[0022] The above terminal can receive information indicating the above reference antenna port.

[0023] The above reference antenna port may be an antenna port linked to an uplink layer indicator included in DCI (downlink control information) that schedules the PUSCH.

[0024] According to another aspect of the present disclosure, a non-transitory computer-readable recording medium having recorded thereon a program for performing the method described above may be provided.

[0025] According to another aspect of the present disclosure, a device includes a memory that stores instructions; and a processor that performs operations by executing the instructions, wherein the operations of the processor include receiving a sounding reference signal (SRS) configuration through upper layer signaling; performing SRS resource mapping for a plurality of SRS antenna ports based on the SRS configuration; and transmitting an SRS through the plurality of SRS antenna ports based on the SRS resource mapping, wherein based on the number of the plurality of SRS antenna ports being 3, the device: performs the SRS resource mapping based on an SRS resource mapping scheme defined for four SRS antenna ports, and performs the SRS transmission by muting a last SRS port among the four SRS antenna ports.

[0026] The above device may further include a transmitter and receiver.

[0027] The above device may be a terminal operating in a wireless communication system.

[0028] The above device may be a processing device configured to control a terminal operating in a wireless communication system.

[0029] According to another aspect of the present disclosure, a method performed by a base station includes transmitting a sounding reference signal (SRS) configuration through upper layer signaling; and receiving an SRS transmitted through a plurality of SRS antenna ports based on the SRS configuration, wherein based on the number of the plurality of SRS antenna ports being 3, the base station receives the SRS based on an SRS resource mapping scheme defined for four SRS antenna ports, and a last SRS port among the four SRS antenna ports may be muted.

[0030] According to another aspect of the present disclosure, a non-transitory computer-readable recording medium having recorded thereon a program for performing the method described above may be provided.

[0031] According to another aspect of the present disclosure, a base station includes a memory for storing commands; and a processor for performing operations by executing the commands, wherein the operations of the processor include transmitting a sounding reference signal (SRS) configuration through upper layer signaling; and receiving an SRS transmitted through a plurality of SRS antenna ports based on the SRS configuration, wherein based on the number of the plurality of SRS antenna ports being 3, the base station receives the SRS based on an SRS resource mapping scheme defined for four SRS antenna ports, and a last SRS port among the four SRS antenna ports may be muted.

[0032] According to one embodiment, wireless signal transmission and reception can be efficiently performed in a wireless communication system. According to one embodiment, UL transmission can be performed more efficiently through a newly defined uplink codebook and SRS transmission method for a 3-Tx port.

[0033] Other effects can be inferred from the description below.

[0034] Figure 1 illustrates physical channels used in a 3GPP system, which is an example of a wireless communication system, and a general signal transmission method using the channels.

[0035] Figure 2 illustrates the structure of a radio frame.

[0036] Figure 3 illustrates a resource grid of slots.

[0037] Figure 4 illustrates an example of physical channels being mapped within a slot.

[0038] Figure 5 illustrates the PDSCH and ACK / NACK transmission process.

[0039] Figure 6 illustrates a PUSCH transmission process.

[0040] Figure 7 shows an example of a CSI-related procedure.

[0041] Figure 8 illustrates multiple TRP transmissions.

[0042] Figure 9 illustrates an example of a partial-coherent antenna configuration.

[0043] Figure 10 illustrates another example of a partial-coherent antenna configuration.

[0044] Figure 11 is an example of the uplink 3Tx antenna layout of a terminal.

[0045] Figure 12 illustrates an implementation example of the operation of a network and a terminal according to one embodiment.

[0046] Fig. 13 illustrates an implementation example of the operation of a terminal in a wireless communication system according to one embodiment.

[0047] FIG. 14 illustrates an implementation example of the operation of a base station in a wireless communication system according to one embodiment.

[0048] Figures 15 to 18 illustrate a communication system (1) and a wireless device applicable to the embodiments.

[0049] The following technologies can be used in various wireless access systems, such as CDMA (code division multiple access), FDMA (frequency division multiple access), TDMA (time division multiple access), OFDMA (orthogonal frequency division multiple access), and SC-FDMA (single carrier frequency division multiple access). CDMA can be implemented with radio technologies such as UTRA (Universal Terrestrial Radio Access) or CDMA2000. TDMA can be implemented with radio technologies such as GSM (Global System for Mobile communications) / GPRS (General Packet Radio Service) / EDGE (Enhanced Data Rates for GSM Evolution). OFDMA can be implemented with radio technologies such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, and E-UTRA (Evolved UTRA). UTRA is a part of UMTS (Universal Mobile Telecommunications System). 3GPP (3rd Generation Partnership Project) LTE (long term evolution) is part of E-UMTS (Evolved UMTS) that uses E-UTRA, and LTE-A (Advanced) is an evolved version of 3GPP LTE. 3GPP NR (New Radio or New Radio Access Technology) is an evolved version of 3GPP LTE / LTE-A.

[0050] As more and more communication devices demand greater communication capacity, the need for improved mobile broadband communications compared to existing RAT (Radio Access Technology) is emerging. Furthermore, massive MTC (Machine Type Communications), which connects multiple devices and objects to provide diverse services anytime, anywhere, is also a key issue to be considered in next-generation communications. Furthermore, communication system design that considers reliability and latency-sensitive services / terminals is being discussed. Accordingly, the introduction of next-generation RATs that consider enhanced Mobile BroadBand Communication (eMBB), massive MTC, and Ultra-Reliable and Low Latency Communication (URLLC) is being discussed. For convenience, this technology is referred to as NR (New Radio or New RAT) in the present invention.

[0051] For clarity of explanation, the description will focus on 3GPP NR, but the technical idea of ​​the present invention is not limited thereto.

[0052] In this specification, the expression "setting" can be replaced with the expression "configure / configuration", and the two can be used interchangeably. In addition, conditional expressions (e.g., "if", "in a case", or "when", etc.) can be replaced with the expression "based on that ~~" or "in a state / status". In addition, the operation of the terminal / base station or the SW / HW configuration according to the satisfaction of the condition can be inferred / understood. In addition, if the process of the receiving (or transmitting) side can be inferred / understood from the process of the transmitting (or receiving) side in signal transmission / reception between wireless communication devices (e.g., base stations, terminals), the description thereof can be omitted. For example, signal determination / generation / encoding / transmission, etc. of the transmitting side can be understood as signal monitoring reception / decoding / determination, etc. of the receiving side. In addition, the expression that the terminal performs (or does not perform) a specific operation can also be interpreted as meaning that the base station operates while expecting / assuming (or expecting / assuming that the terminal does not perform) the specific operation. In addition, the expression that the base station performs (or does not perform) a specific operation can also be interpreted as meaning that the terminal operates while expecting / assuming (or expecting / assuming that the base station does not perform) the specific operation. In addition, the division and index of each section, embodiment, example, option, method, plan, etc. in the following description are for the convenience of explanation and should not be interpreted as meaning that each constitutes an independent invention or that each must be implemented only individually. In addition, in describing each section, embodiment, example, option, method, plan, etc., if there is no explicitly conflicting / opposing description, it can be inferred / interpreted that at least some of them can be combined and implemented together, or at least some can be implemented with the omission of each.

[0053] In a wireless communication system, a terminal receives information from a base station via the downlink (DL) and transmits it to the base station via the uplink (UL). The information transmitted and received between the base station and the terminal includes data and various control information, and various physical channels exist depending on the type and purpose of the information being transmitted and received.

[0054] Figure 1 is a drawing for explaining physical channels used in a 3GPP NR system and a general signal transmission method using them.

[0055] When a terminal is powered on again from a powered-off state or enters a new cell, it performs an initial cell search operation, such as synchronizing with the base station, in step S101. To this end, the terminal receives a Synchronization Signal Block (SSB) from the base station. The SSB includes a Primary Synchronization Signal (PSS), a Secondary Synchronization Signal (SSS), and a Physical Broadcast Channel (PBCH). Based on the PSS / SSS, the terminal synchronizes with the base station and obtains information such as a cell ID (cell identity). In addition, the terminal can obtain broadcast information within the cell based on the PBCH. Meanwhile, the terminal can check the downlink channel status by receiving a Downlink Reference Signal (DL RS) during the initial cell search phase.

[0056] After completing the initial cell search, the terminal can obtain more specific system information by receiving a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH) based on the physical downlink control channel information in step S102.

[0057] Thereafter, the terminal may perform a random access procedure such as steps S103 to S106 to complete connection to the base station. To this end, the terminal may transmit a preamble through a physical random access channel (PRACH) (S103) and receive a response message to the preamble through a physical downlink control channel and a corresponding physical downlink shared channel (S104). In the case of contention-based random access, a contention resolution procedure such as transmission of an additional physical random access channel (S105) and reception of a physical downlink control channel and a corresponding physical downlink shared channel (S106) may be performed.

[0058] The terminal that has performed the procedure as described above can then perform the general uplink / downlink signal transmission procedure, such as receiving a physical downlink control channel / physical downlink shared channel (S107) and transmitting a physical uplink shared channel (PUSCH) / physical uplink control channel (PUCCH) (S108). The control information that the terminal transmits to the base station is collectively referred to as uplink control information (UCI). UCI includes HARQ ACK / NACK (Hybrid Automatic Repeat and request Acknowledgement / Negative-ACK), SR (Scheduling Request), CSI (Channel State Information), etc. CSI includes CQI (Channel Quality Indicator), PMI (Precoding Matrix Indicator), RI (Rank Indication), etc. UCI is generally transmitted through PUCCH, but can be transmitted through PUSCH when control information and traffic data must be transmitted simultaneously. Additionally, UCI can be transmitted aperiodically via PUSCH upon request / instruction from the network.

[0059] Figure 2 illustrates the structure of a radio frame. In NR, uplink and downlink transmissions are organized into frames. Each radio frame is 10 ms long and is divided into two 5 ms half-frames (HF). Each half-frame is divided into five 1 ms sub-frames (SF). A sub-frame is divided into one or more slots, and the number of slots within a sub-frame depends on the subcarrier spacing (SCS). Each slot contains 12 or 14 OFDM (Orthogonal Frequency Division Multiplexing) symbols, depending on the cyclic prefix (CP). When a normal CP is used, each slot contains 14 OFDM symbols. When an extended CP is used, each slot contains 12 OFDM symbols.

[0060] Table 1 illustrates that when CP is normally used, the number of symbols per slot, the number of slots per frame, and the number of slots per subframe vary depending on the SCS.

[0061] SCS (15*2^u)N slot symb N frame,u slot N subframe,u slot 15KHz (u=0)1410130KHz (u=1)1420260KHz (u=2)14404120KHz (u=3)14808240KHz (u=4)1416016

[0062] * N slot symb : Number of symbols in the slot

[0063] * N frame,u slot : Number of slots in the frame

[0064] * N subframe,u slot : Number of slots in a subframe

[0065] Table 2 illustrates that when extended CP is used, the number of symbols per slot, the number of slots per frame, and the number of slots per subframe vary depending on the SCS.

[0066] SCS (15*2^u)N slot symb N frame,u slot N subframe,u slot 60KHz (u=2)12404

[0067] The structure of the frame is only an example, and the number of subframes, number of slots, and number of symbols in the frame can be varied.

[0068] In an NR system, OFDM numerology (e.g., SCS) may be set differently between multiple cells that are merged into a single terminal. Accordingly, the (absolute time) interval of a time resource (e.g., SF, slot, or TTI) (conveniently referred to as TU (Time Unit)) consisting of the same number of symbols may be set differently between the merged cells. Here, the symbol may include an OFDM symbol (or CP-OFDM symbol), an SC-FDMA symbol (or Discrete Fourier Transform-spread-OFDM, DFT-s-OFDM symbol).

[0069] Figure 3 illustrates a resource grid of a slot. A slot contains multiple symbols in the time domain. For example, in the case of a regular CP, one slot contains 14 symbols, but in the case of an extended CP, one slot contains 12 symbols. A carrier contains multiple subcarriers in the frequency domain. A Resource Block (RB) is defined as multiple (e.g., 12) consecutive subcarriers in the frequency domain. A Bandwidth Part (BWP) is defined as multiple consecutive Physical RBs (PRBs) in the frequency domain and can correspond to a single numerology (e.g., SCS, CP length, etc.). A carrier can contain up to N (e.g., 5) BWPs. Data communication is performed through activated BWPs, and only one BWP can be activated for a single terminal. Each element in the resource grid is referred to as a Resource Element (RE), to which one complex symbol can be mapped.

[0070] Figure 4 illustrates an example of how physical channels are mapped within a slot. A PDCCH can be transmitted in the DL control region, and a PDSCH can be transmitted in the DL data region. A PUCCH can be transmitted in the UL control region, and a PUSCH can be transmitted in the UL data region. GP provides a time gap between the base station and the terminal when switching from transmission mode to reception mode or from reception mode to transmission mode. Some symbols within a subframe at the time of transition from DL to UL can be set as GP.

[0071] Below, each physical channel is described in more detail.

[0072] The PDCCH carries Downlink Control Information (DCI). For example, the PCCCH (DCI) carries the transmission format and resource allocation of the downlink shared channel (DL-SCH), resource allocation information for the uplink shared channel (UL-SCH), paging information for the paging channel (PCH), system information on the DL-SCH, resource allocation information for upper-layer control messages such as random access responses transmitted on the PDSCH, transmission power control commands, activation / deactivation of Configured Scheduling (CS), etc. The DCI includes a cyclic redundancy check (CRC), which is masked / scrambled with various identifiers (e.g., Radio Network Temporary Identifier, RNTI) depending on the owner or usage of the PDCCH. For example, if the PDCCH is for a specific terminal, the CRC is masked with a terminal identifier (e.g., Cell-RNTI, C-RNTI). If the PDCCH is for paging, the CRC is masked with the Paging-RNTI (P-RNTI). If the PDCCH is for system information (e.g., a System Information Block, SIB), the CRC is masked with the System Information RNTI (SI-RNTI). If the PDCCH is for a random access response, the CRC is masked with the Random Access-RNTI (RA-RNTI).

[0073] The PDCCH consists of 1, 2, 4, 8, or 16 Control Channel Elements (CCEs) depending on the Aggregation Level (AL). A CCE is a logical allocation unit used to provide a PDCCH with a predetermined code rate depending on the radio channel status. A CCE consists of six Resource Element Groups (REGs). A REG is defined as one OFDM symbol and one (P)RB. The PDCCH is transmitted through a Control Resource Set (CORESET). A CORESET is defined as a set of REGs with a given numerology (e.g., SCS, CP length, etc.). Multiple CORESETs for a single UE can overlap in the time / frequency domain. A CORESET can be configured through system information (e.g., Master Information Block, MIB) or UE-specific upper layer (e.g., Radio Resource Control, RRC, layer) signaling. Specifically, the number of RBs and the number of OFDM symbols (up to 3) that constitute the CORESET can be set by upper layer signaling.

[0074] To receive / detect PDCCH, the UE monitors PDCCH candidates. PDCCH candidates represent the CCE(s) that the UE should monitor for PDCCH detection. Each PDCCH candidate is defined as 1, 2, 4, 8, or 16 CCEs depending on the AL. Monitoring involves (blind) decoding the PDCCH candidates. The set of PDCCH candidates that the UE monitors is defined as a PDCCH Search Space (SS). The search space includes a Common Search Space (CSS) or a UE-specific search space (USS). The UE can acquire DCI by monitoring PDCCH candidates in one or more search spaces configured by the MIB or higher-layer signaling. Each CORESET is associated with one or more search spaces, and each search space is associated with one COREST. The search space can be defined based on the following parameters.

[0075] - controlResourceSetId: Indicates the CORESET associated with the search space.

[0076] - monitoringSlotPeriodicityAndOffset: Indicates the PDCCH monitoring period (in slots) and the PDCCH monitoring interval offset (in slots).

[0077] - monitoringSymbolsWithinSlot: Indicates the PDCCH monitoring symbols within the slot (e.g., the first symbol(s) of the CORESET).

[0078] - nrofCandidates: AL={1, 2, 4, 8, 16} indicates the number of PDCCH candidates (one of 0, 1, 2, 3, 4, 5, 6, 8)

[0079] * An opportunity (e.g., time / frequency resource) for monitoring PDCCH candidates is defined as a PDCCH (monitoring) opportunity. One or more PDCCH (monitoring) opportunities can be configured within a slot.

[0080] Table 3 illustrates the characteristics of each search space type.

[0081] TypeSearch SpaceRNTIUse CaseType0-PDCCHCommonSI-RNTI on a primary cellSIB DecodingType0A-PDCCHCommonSI-RNTI on a primary cellSIB DecodingType1-PDCCHCommonRA-RNTI or TC-RNTI on a primary cellMsg2, Msg4 decoding in RACHType2-PDCCHCommonP-RNTI on a primary cellPaging DecodingType3-PDCCHCommonINT-RNTI, SFI-RNTI, TPC-PUSCH-RNTI, TPC-PUCCH-RNTI, TPC-SRS-RNTI, C-RNTI, MCS-C-RNTI, or CS-RNTI(s)UE SpecificUE SpecificC-RNTI, or MCS-C-RNTI, or CS-RNTI(s)User specific PDSCH decoding

[0082] Table 4 illustrates DCI formats transmitted via PDCCH.

[0083] DCI formatUsage0_0Scheduling of PUSCH in one cell0_1Scheduling of PUSCH in one cell1_0Scheduling of PDSCH in one cell1_1Scheduling of PDSCH in one cell2_0Notifying a group of UEs of the slot format2_1Notifying a group of UEs of the PRB(s) and OFDM symbol(s) where UE may assume no transmission is intended for the UE2_2Transmission of TPC commands for PUCCH and PUSCH2_3Transmission of a group of TPC commands for SRS transmissions by one or more UEs

[0084] DCI format 0_0 is used to schedule a TB-based (or TB-level) PUSCH, and DCI format 0_1 ​​can be used to schedule a TB-based (or TB-level) PUSCH or a CBG (Code Block Group)-based (or CBG-level) PUSCH. DCI format 1_0 is used to schedule a TB-based (or TB-level) PDSCH, and DCI format 1_1 can be used to schedule a TB-based (or TB-level) PDSCH or a CBG-based (or CBG-level) PDSCH (DL grant DCI). DCI format 0_0 / 0_1 may be referred to as UL grant DCI or UL scheduling information, and DCI format 1_0 / 1_1 may be referred to as DL grant DCI or DL ​​scheduling information. DCI format 2_0 is used to convey dynamic slot format information (e.g., dynamic SFI) to the terminal, and DCI format 2_1 is used to convey downlink pre-emption information to the terminal. DCI format 2_0 and / or DCI format 2_1 can be conveyed to the terminals within a group through the group common PDCCH, which is a PDCCH conveyed to the terminals defined as a group.

[0085] DCI format 0_0 and DCI format 1_0 may be referred to as fallback DCI formats, while DCI format 0_1 ​​and DCI format 1_1 may be referred to as non-fallback DCI formats. In the fallback DCI format, the DCI size / field configuration remains the same regardless of the terminal configuration. On the other hand, in the non-fallback DCI format, the DCI size / field configuration varies depending on the terminal configuration.

[0086] PDSCH carries downlink data (e.g., DL-SCH transport block, DL-SCH TB) and applies modulation methods such as Quadrature Phase Shift Keying (QPSK), 16 Quadrature Amplitude Modulation (QAM), 64 QAM, and 256 QAM. TB is encoded to generate a codeword. PDSCH can carry up to two codewords. Scrambling and modulation mapping are performed for each codeword, and modulation symbols generated from each codeword can be mapped to one or more layers. Each layer is mapped to resources along with a Demodulation Reference Signal (DMRS), generated as an OFDM symbol signal, and transmitted through the corresponding antenna port.

[0087] PUCCH carries Uplink Control Information (UCI). UCI includes:

[0088] - SR (Scheduling Request): Information used to request UL-SCH resources.

[0089] - HARQ(Hybrid Automatic Repeat reQuest)-ACK(Acknowledgement): This is a response to a downlink data packet (e.g., codeword) on the PDSCH. It indicates whether the downlink data packet was successfully received. One HARQ-ACK bit can be transmitted in response to a single codeword, and two HARQ-ACK bits can be transmitted in response to two codewords. The HARQ-ACK response includes a positive ACK (simply, ACK), a negative ACK (NACK), a DTX, or a NACK / DTX. Here, HARQ-ACK is used interchangeably with HARQ ACK / NACK and ACK / NACK.

[0090] - CSI (Channel State Information): Feedback information for the downlink channel. MIMO (Multiple Input Multiple Output)-related feedback information includes the Rank Indicator (RI) and Precoding Matrix Indicator (PMI).

[0091] Table 5 illustrates PUCCH formats. Depending on the PUCCH transmission length, they can be classified into Short PUCCH (formats 0 and 2) and Long PUCCH (formats 1, 3, and 4).

[0092] PUCCH formatLength in OFDM symbols N PUCCH symb Number of bitsUsageEtc01 - 2≤2HARQ, SRSequence selection14 - 14≤2HARQ, [SR]Sequence modulation21 - 2>2HARQ, CSI, [SR]CP-OFDM34 - 14>2HARQ, CSI, [SR]DFT-s-OFDM(no UE multiplexing)44 - 14>2HARQ, CSI, [SR]DFT-s-OFDM(Pre DFT OCC)

[0093] PUCCH format 0 carries UCI of up to 2 bits in size and is mapped and transmitted based on sequence. Specifically, the terminal transmits a specific UCI to the base station by transmitting one of multiple sequences through the PUCCH of PUCCH format 0. The terminal transmits the PUCCH of PUCCH format 0 within the PUCCH resources for the corresponding SR configuration only when transmitting a positive SR.

[0094] PUCCH format 1 carries UCI of up to 2 bits in size, and modulation symbols are spread in the time domain using an orthogonal cover code (OCC) (which is set differently depending on whether frequency hopping is used). DMRS is transmitted in symbols where modulation symbols are not transmitted (transmitted using Time Division Multiplexing (TDM)).

[0095] PUCCH format 2 carries UCI with a bit size greater than 2 bits, and modulation symbols are transmitted by frequency division multiplexing (FDM) with DMRS. DM-RSs are located at symbol indices #1, #4, #7, and #10 within a given resource block with a density of 1 / 3. Pseudo Noise (PN) sequences are used for DM_RS sequences. Frequency hopping can be enabled for 2-symbol PUCCH format 2.

[0096] PUCCH format 3 does not multiplex terminals within the same physical resource blocks and carries UCI with a bit size greater than 2 bits. In other words, PUCCH resources in PUCCH format 3 do not include orthogonal cover codes. Modulation symbols are transmitted through time division multiplexing (TDM) with DMRS.

[0097] PUCCH format 4 supports multiplexing of up to four terminals within the same physical resource blocks and carries UCI with a bit size greater than 2 bits. In other words, PUCCH resources in PUCCH format 3 include orthogonal cover codes. Modulation symbols are transmitted through time division multiplexing (TDM) with DMRS.

[0098] At least one of one or more configured cells in a terminal may be configured for PUCCH transmission. At least the primary cell may be configured as a cell for PUCCH transmission. At least one PUCCH cell group may be configured in the terminal based on at least one cell configured for PUCCH transmission, and each PUCCH cell group includes one or more cells. The PUCCH cell group may be simply referred to as a PUCCH group. PUCCH transmission may be configured not only for the primary cell but also for the SCell, and the primary cell belongs to the primary PUCCH group, and the PUCCH-SCell configured for PUCCH transmission belongs to the secondary PUCCH group. For cells belonging to the primary PUCCH group, the PUCCH on the primary cell may be used, and for cells belonging to the secondary PUCCH group, the PUCCH on the PUCCH-SCell may be used.

[0099] PUSCH carries uplink data (e.g., UL-SCH transport block, UL-SCH TB) and / or uplink control information (UCI), and is transmitted based on a CP-OFDM (Cyclic Prefix - Orthogonal Frequency Division Multiplexing) waveform or a DFT-s-OFDM (Discrete Fourier Transform - spread - Orthogonal Frequency Division Multiplexing) waveform. When the PUSCH is transmitted based on a DFT-s-OFDM waveform, the UE transmits the PUSCH by applying transform precoding. For example, when transform precoding is disabled (e.g., transform precoding is disabled), the UE transmits the PUSCH based on the CP-OFDM waveform, and when transform precoding is enabled (e.g., transform precoding is enabled), the UE can transmit the PUSCH based on the CP-OFDM waveform or the DFT-s-OFDM waveform. PUSCH transmissions can be dynamically scheduled by UL grants in DCI, or semi-statically scheduled (configured grant) based on higher layer (e.g., RRC) signaling (and / or Layer 1 (L1) signaling (e.g., PDCCH)). PUSCH transmissions can be performed in a codebook-based or non-codebook-based manner.

[0100] Figure 5 illustrates an ACK / NACK transmission process. Referring to Figure 5, a terminal can detect a PDCCH in slot #n. Here, the PDCCH includes downlink scheduling information (e.g., DCI formats 1_0, 1_1), and the PDCCH indicates a DL assignment-to-PDSCH offset (K0) and a PDSCH-HARQ-ACK reporting offset (K1). For example, DCI formats 1_0, 1_1 can include the following information:

[0101] - Frequency domain resource assignment: Indicates the set of RBs allocated to the PDSCH.

[0102] - Time domain resource assignment: K0 (e.g., slot offset), indicates the starting position of the PDSCH within slot #n+K0 (e.g., OFDM symbol index), and the length of the PDSCH (e.g., number of OFDM symbols).

[0103] - PDSCH-to-HARQ_feedback timing indicator: Indicates K1

[0104] - HARQ process number (4 bits): Indicates the HARQ process ID (Identity) for data (e.g., PDSCH, TB)

[0105] - PUCCH resource indicator (PRI): Indicates the PUCCH resource to be used for UCI transmission among multiple PUCCH resources within the PUCCH resource set.

[0106] Afterwards, the terminal receives PDSCH from slot #(n+K0) according to the scheduling information of slot #n, and when reception of PDSCH is finished in slot #n1 (where, n+K0≤n1), UCI can be transmitted through PUCCH in slot #(n1+K1). Here, UCI may include HARQ-ACK response for PDSCH. In Fig. 5, for convenience, it is assumed that SCS for PDSCH and SCS for PUCCH are the same and slot # n1 = slot #n+K0, but the present invention is not limited thereto. If the SCSs are different, K1 can be indicated / interpreted based on the SCS of PUCCH.

[0107] When the PDSCH is configured to transmit at most 1 TB, the HARQ-ACK response may consist of 1 bit. When the PDSCH is configured to transmit at most 2 TB, the HARQ-ACK response may consist of 2 bits if spatial bundling is not configured, and may consist of 1 bit if spatial bundling is configured. When the HARQ-ACK transmission timing for multiple PDSCHs is designated as slot #(n+K1), the UCI transmitted in slot #(n+K1) includes HARQ-ACK responses for multiple PDSCHs.

[0108] Whether a UE should perform spatial bundling for a HARQ-ACK response can be configured (e.g., via RRC / higher layer signaling) for each cell group. For example, spatial bundling can be individually configured for each HARQ-ACK response transmitted over the PUCCH and / or each HARQ-ACK response transmitted over the PUSCH.

[0109] Spatial bundling can be supported when the maximum number of TBs (or codewords) that can be received at a time (or scheduled via 1 DCI) in the serving cell is 2 (or more than 2) (e.g., when the upper layer parameter maxNrofCodeWordsScheduledByDCI corresponds to 2-TB). Meanwhile, more than 4 layers can be used for 2-TB transmission, and up to 4 layers can be used for 1-TB transmission. Consequently, when spatial bundling is configured for the cell group, spatial bundling can be performed for serving cells that can schedule more than 4 layers among the serving cells in the cell group. On the serving cell, a terminal that wishes to transmit a HARQ-ACK response via spatial bundling can generate the HARQ-ACK response by performing a (bit-wise) logical AND operation on the A / N bits for multiple TBs.

[0110] For example, assuming that a terminal receives a DCI scheduling 2 TB and receives 2 TB via PDSCH based on the DCI, the terminal performing spatial bundling can generate a single A / N bit by logically ANDing the first A / N bit for the first TB and the second A / N bit for the second TB. Consequently, if both the first TB and the second TB are ACK, the terminal reports the ACK bit value to the base station, and if either TB is NACK, the terminal reports the NACK bit value to the base station.

[0111] For example, if only 1-TB is actually scheduled on a serving cell configured to receive 2-TB, the terminal can generate a single A / N bit by logically ANDing the A / N bit for the 1-TB with bit value 1. Consequently, the terminal reports the A / N bit for the 1-TB to the base station as is.

[0112] A base station / terminal has multiple parallel DL HARQ processes for DL ​​transmission. These multiple parallel HARQ processes allow DL transmissions to be performed continuously while waiting for HARQ feedback regarding the successful or unsuccessful reception of a previous DL transmission. Each HARQ process is associated with a HARQ buffer in the MAC (Medium Access Control) layer. Each DL HARQ process manages state variables such as the number of transmissions of MAC Physical Data Blocks (PDUs) in the buffer, HARQ feedback for MAC PDUs in the buffer, and the current redundancy version. Each HARQ process is identified by a HARQ process ID.

[0113] Figure 6 illustrates a PUSCH transmission process. Referring to Figure 6, a terminal can detect a PDCCH in slot #n. Here, the PDCCH includes uplink scheduling information (e.g., DCI formats 0_0 and 0_1). DCI formats 0_0 and 0_1 can include the following information.

[0114] - Frequency domain resource assignment: Indicates the set of RBs allocated to PUSCH.

[0115] - Time domain resource assignment: Slot offset K2 indicates the starting position (e.g., symbol index) and length (e.g., number of OFDM symbols) of the PUSCH within the slot. The starting symbol and length can be indicated through SLIV (Start and Length Indicator Value) or can be indicated separately.

[0116] Thereafter, the terminal can transmit a PUSCH in slot #(n+K2) according to the scheduling information of slot #n. Here, the PUSCH includes a UL-SCH TB.

[0117] SRS (sounding reference signal)

[0118] SRS is a UL reference signal transmitted by the terminal and received by the base station. Based on SRS, the base station can perform link adaptation, DL channel estimation using channel reciprocity characteristics, UL beam management, UL precoding, and / or UL measurement acquisition.

[0119] The terminal can receive SRS configuration information (e.g., TS38.331 SRS-Config IE) provided by the base station and determine parameters for SRS transmission based on the information. The SRS configuration is composed of a list of SRS-Resources, SRS-PosResources, SRS-ResourceSets, and SRS-PosResourcesets, where SRS-ResourceSets and SRS-PosResourcesets each contain a set of SRS-Resources and SRS-PosResources.

[0120] Table 6 is an excerpt from the TS38.331 SRS-Config IE.

[0121] SRS-ResourceSet ::= SEQUENCE {srs-ResourceSetId SRS-ResourceSetId,srs-ResourceIdList SEQUENCE (SIZE(1..maxNrofSRS-ResourcesPerSet)) OF SRS-ResourceIdresourceType CHOICE {aperiodic SEQUENCE {aperiodicSRS-ResourceTrigger INTEGER (1..maxNrofSRS-TriggerStates-1),csi-RS NZP-CSI-RS-ResourceIdslotOffset INTEGER (1..32)...,[[aperiodicSRS-ResourceTriggerList SEQUENCE (SIZE(1..maxNrofSRS-TriggerStates-2)) OF INTEGER (1..maxNrofSRS-TriggerStates-1)]]},semi-persistent SEQUENCE {associatedCSI-RS NZP-CSI-RS-ResourceId...},periodic SEQUENCE {associatedCSI-RS NZP-CSI-RS-ResourceId...}},usage {beamManagement, codebook, nonCodebook, antennaSwitching},alpha Alphap0 INTEGER (-202..24)pathlossReferenceRS PathlossReferenceRS-Configsrs-PowerControlAdjustmentStates ENUMERATED { sameAsFci2, separateClosedLoop}...,[[pathlossReferenceRSList-r16 SetupRelease { PathlossReferenceRSList-r16} ]]}SRS-Resource ::= SEQUENCE {srs-ResourceId SRS-ResourceId,nrofSRS-Ports ENUMERATED {port1, ports2, ports4},ptrs-PortIndex ENUMERATED {n0, n1}transmissionComb CHOICE {n2 SEQUENCE {combOffset-n2 INTEGER (0..1),cyclicShift-n2 INTEGER (0..7)},n4 SEQUENCE {combOffset-n4 INTEGER (0..3),cyclicShift-n4 INTEGER (0..11)}},resourceMapping SEQUENCE {startPosition INTEGER (0..5),nrofSymbols ENUMERATED {n1, n2, n4},repetitionFactor ENUMERATED {n1, n2, n4}},freqDomainPosition INTEGER (0..67),freqDomainShift INTEGER (0..268),freqHopping SEQUENCE {c-SRS INTEGER (0..63),b-SRS INTEGER (0..3),b-hop INTEGER (0..3)},groupOrSequenceHopping ENUMERATED { neither, groupHopping, sequenceHopping},resourceType CHOICE {aperiodic SEQUENCE {...},semi-persistent SEQUENCE {periodicityAndOffset-sp SRS-PeriodicityAndOffset,...},periodic SEQUENCE {periodicityAndOffset-p SRS-PeriodicityAndOffset,...}},sequenceId INTEGER (0..1023),spatialRelationInfo SRS-SpatialRelationInfo...,[[ resourceMapping-r16 SEQUENCE {startPosition-r16 INTEGER (0..13),nrofSymbols-r16 ENUMERATED {n1, n2, n4},repetitionFactor-r16 ENUMERATED {n1, n2, n4}} ]]}.

[0122] SRS can be divided into three resource types depending on the time resource setting and transmission method.

[0123] In the case of SRS with the resource type set to periodic, the terminal determines the location where the SRS resource is transmitted based on the configured period and offset of the SRS resource set by RRC, and if configured, periodically transmits the SRS without separate signaling.

[0124] For SRS with the resource type set to semi-persistent, the terminal determines the transmission location of the SRS resource based on the configured cycle and offset of the SRS resource set by RRC, and initiates periodic transmission of the indicated SRS if SRS transmission is activated by MAC CE. If deactivated by MAC CE, the terminal stops transmitting the SRS.

[0125] For SRSs where the resource type is set to aperiodic, the terminal transmits the indicated SRS by reflecting the position of the offset set by RRC based on the time of reception of the DCI indicating triggering for the corresponding SRS resource set.

[0126] DCI (e.g., UL scheduling DCI format 0_1, 0_2, etc.) includes an SRS resource indicator (SRI) and an SRS request. The SRI field can indicate SRS resources configured within the SRS resource set associated with the upper layer parameter 'usage'. In addition, 'spatialRelationInfo' can be configured for each SRS resource, and its value can be one of {CRI, SSB, SRI}.

[0127] i) In codebook-based PUSCH transmission, the UE can determine a PUSCH transmission precoder based on the SRI, TPMI (Transmit Precoding Matrix Indicator) and transmission rank of the DCI. The TPMI is used to indicate a precoder to be applied across antenna ports, and corresponds to an SRS resource selected by the SRI when multiple SRS resources are configured. Alternatively, when a single SRS resource is configured, the TPMI is used to indicate a precoder to be applied across antenna ports, and corresponds to the single SRS resource. The transmission precoder is selected from an uplink codebook having the same number of antenna ports as the upper layer parameter 'nrofSRS-Ports'. When the upper layer in which the UE is set to 'codebook' is configured with the parameter 'txConfig', the UE is configured with at least one SRS resource. The SRI indicated in slot n is associated with the most recent transmission of the SRS resource identified by the SRI, where the SRS resource precedes the PDCCH (slot n) carrying the SRI.

[0128] ii) In non-codebook based PUSCH transmission, when multiple SRS resources are configured, the UE can determine the PUSCH precoder and transmission rank based on the wideband SRI, where the SRI is given by the SRS resource indicator in the DCI or by the higher layer parameter 'srs-ResourceIndicator'. The UE uses one or multiple SRS resources for SRS transmission, where the number of SRS resources can be configured for simultaneous transmission within the same RB based on the UE capability. Only one SRS port is configured for each SRS resource. Only one SRS resource can be configured with the higher layer parameter 'usage' set to 'nonCodebook'. The maximum number of SRS resources that can be configured for non-codebook based uplink transmission is 4. The SRI indicated in slot n is associated with the most recent transmission of the SRS resource identified by the SRI, where the SRS transmission precedes the PDCCH (slot n) carrying the SRI.

[0129] SRS enhancement in Rel-17 MIMO

[0130] In NR TDD systems, the importance of SRS transmission at terminals to ensure UL and DL channel estimation performance has increased. Accordingly, Rel-17 MIMO standardization was conducted with the following three goals in mind.

[0131] First, standardization was carried out with the goal of more flexibly controlling aperiodic SRS transmission according to the DL and UL slot ratios and traffic conditions of various TDD systems.

[0132] Second, NR terminals supporting DL Rank 8 transmission must be equipped with at least 8 receive antennas, but the SRS antenna switching transmission technique for estimating DL channels based on channel reciprocity in NR TDD systems only supports terminals with up to 4 receive antennas. Therefore, Rel-17 standardized the technique with the goal of supporting the SRS antenna switching transmission technique for terminals equipped with more than 4 receive antennas.

[0133] Third, standardization was carried out to increase the transmission coverage of SRS and increase the capacity of SRS considering simultaneous access of multiple terminals.

[0134] A more flexible aperiodic SRS transmission triggering technique

[0135] In order to more flexibly control aperiodic SRS transmission according to the DL and UL slot ratios and traffic conditions of various TDD systems in Rel-17 MIMO, the following two techniques were standardized.

[0136] First, to solve the problem that the slot offset value for the aperiodic SRS transmission trigger is fixed semi-statically through the RRC message, which may cause a significant delay in SRS transmission depending on the DL and UL slot settings, a technique was introduced to dynamically control the slot offset value for the aperiodic SRS transmission trigger through DCI. To this end, a new DCI field was defined that specifies one of multiple slot offset values ​​set by the RRC message. In addition, the slot offset value indicated through the DCI field was standardized to be calculated based on available slots defined as uplink slots and slots composed of flexible symbols, thereby enabling flexible SRS transmission triggering with a small number of slot offset candidate values.

[0137] Another issue is that, previously, aperiodic SRS transmissions could only be triggered via UL DCI when PUSCH allocation triggered UL data and / or CSI reporting. Therefore, it was difficult for base stations to estimate UL / DL channels by triggering SRS for UEs that had no UL data to transmit and no need for aperiodic CSI reporting. To address this issue, Rel-17 MIMO introduced a technique for triggering aperiodic SRS transmissions without accompanying UL data transmission and CSI reporting.

[0138] SRS antenna change transmission for terminals equipped with more than four receiving antennas

[0139] As previously described, the SRS antenna switching transmission technique supported in the Rel-15 / 16 NR system only considered terminals equipped with four receive antennas. In Rel-17 MIMO, the SRS antenna switching transmission method was standardized for terminals equipped with six and eight receive antennas. The extended antenna switching transmission method supports the following combinations of the number of transmit antennas Nt and the number of receive antennas Nr.

[0140] Terminal with Nr=6: Nt=1, Nt=2,

[0141] Terminals with Nr=8: Nt=1, Nt=2, Nt=4

[0142] The above SRS transmission can be transmitted within one slot, or across two or four slots.

[0143] SRS Coverage and Capacity Enhancement Techniques

[0144] In Rel-17 MIMO, three major techniques were introduced to increase the coverage and capacity of SRS.

[0145] First, the maximum number of repetitions of SRS was increased to enable utilization in systems requiring wider coverage. In Rel-15 and Rel-16, SRS could be repeated in up to 4 symbols within a slot, except for cases for positioning. In Rel-17 MIMO, SRS can be repeated in up to 14 symbols within a slot to secure wider SRS coverage. Specifically, SRS can be transmitted in 8, 10, 12, or 14 consecutive symbols within a slot.

[0146] Another approach is to enable SRS transmission only in partial bands. To achieve this, the base station can configure the resource block location where SRS transmission begins and the SRS transmission band for the terminal. For SRS transmission, the corresponding frequency location can also be hopped or fixed according to established rules, depending on the SRS frequency hopping cycle. The introduction of this technique allows different terminals to simultaneously transmit SRS to the same base station in different partial bands, thereby increasing SRS capacity.

[0147] Finally, we support SRS with lower frequency densities. In Rel-15 / 16, except for positioning, the supported SRS frequency density was 1 RE per 2 REs or 1 RE per 4 REs. While this ensured stable channel estimation performance in frequency-selective channel environments, it limited SRS capacity. Therefore, in Rel-17 MIMO, we additionally introduced a transmission technique that transmits SRS on 1 RE per 8 REs, thereby further increasing SRS capacity in frequency-nonselective channel environments.

[0148] CSI-related actions

[0149] Figure 7 shows an example of a CSI-related procedure.

[0150] The terminal receives configuration information related to CSI from the base station via RRC signaling (710). The configuration information related to CSI may include at least one of CSI-IM (interference management) resource-related information, CSI measurement configuration-related information, CSI resource configuration-related information, CSI-RS resource-related information, or CSI report configuration-related information.

[0151] - CSI-IM resources can be configured for interference measurement (IM) of the terminal. In the time domain, the CSI-IM resource set can be configured periodically, semi-persistently, or aperiodicly. The CSI-IM resources can be configured as Zero Power (ZP)-CSI-RS for the terminal. The ZP-CSI-RS can be configured separately from the Non-Zero Power (NZP)-CSI-RS.

[0152] - The UE may assume that the CSI-RS resource(s) for channel measurement configured for one CSI reporting and the CSI-IM / NZP CSI-RS resource(s) for interference measurement (when NZP CSI-RS resource(s) are used for interference measurement) are in a QCL relationship with respect to 'QCL-TypeD' per resource.

[0153] - The CSI resource configuration may include at least one of a CSI-IM resource for interference measurement, an NZP CSI-RS resource for interference measurement, and an NZP CSI-RS resource for channel measurement. The CMR (channel measurement resource) may be an NZP CSI-RS for CSI acquisition, and the IMR (Interference measurement resource) may be an NZP CSI-RS for CSI-IM and IM.

[0154] - CSI-RS can be configured for one or more terminals. Different CSI-RS configurations may be provided for each terminal, or the same CSI-RS configuration may be provided to multiple terminals. CSI-RS can support up to 32 antenna ports. CSI-RS corresponding to N (N is 1 or greater) antenna ports can be mapped to N RE locations within a time-frequency unit corresponding to one slot and one RB. When N is 2 or greater, N-port CSI-RS can be multiplexed using CDM, FDM, and / or TDM schemes. CSI-RS can be mapped to REs other than REs to which CORESET, DMRS, and SSB are mapped. In the frequency domain, CSI-RS can be configured for the entire bandwidth, a portion of the bandwidth (BWP), or a portion of the bandwidth. CSI-RS may be transmitted in each RB within the bandwidth for which CSI-RS is configured (density = 1), or in every second RB (e.g., even or odd RB) (density = 1 / 2). When CSI-RS is used as a Tracking Reference Signal (TRS), a single-port CSI-RS may be mapped on three subcarriers in each resource block (density = 3). One or more CSI-RS resource sets may be configured for a UE in the time domain. Each CSI-RS resource set may include one or more CSI-RS configurations. Each CSI-RS resource set may be configured periodically, semi-persistently, or aperiodicly.

[0155] - The CSI report configuration may include configurations for feedback type, measurement resources, report type, etc. The NZP-CSI-RS resource set may be used for the CSI report configuration of the corresponding terminal. The NZP-CSI-RS resource set may be associated with CSI-RS or SSB. In addition, multiple periodic NZP-CSI-RS resource sets may be configured as TRS resource sets. (i) The feedback type may include a Channel Quality Indicator (CQI), a Precoding Matrix Indicator (PMI), a CSI-RS Resource Indicator (CRI), an SSB Resource block Indicator (SSBRI), a Layer Indicator (LI), a Rank Indicator (RI), a Layer 1-Reference Signal Received Strength (RSRP), etc. (ii) Measurement resources may include configurations for downlink signals and / or downlink resources on which the terminal performs measurements to determine feedback information. The measurement resources may be configured as ZP and / or NZP CSI-RS resource sets associated with CSI reporting configurations. The NZP CSI-RS resource set may include a CSI-RS set or an SSB set. For example, L1-RSRP may be measured for a CSI-RS set or an SSB set. (iii) Reporting types may include configurations for a time point at which the terminal performs reporting and an uplink channel, etc. The reporting time point may be configured as periodic, semi-persistent, or aperiodic. Periodic CSI reporting may be transmitted on PUCCH. Semi-persistent CSI reporting may be transmitted on PUCCH or PUSCH based on a MAC CE indicating activation / deactivation. Aperiodic CSI reporting may be indicated by DCI signaling.For example, the CSI request field of an uplink grant may indicate one of several report trigger sizes. Aperiodic CSI reports may be transmitted on the PUSCH.

[0156] The terminal measures CSI based on configuration information related to CSI. CSI measurement may include a procedure of receiving a CSI-RS (720) and computing the received CSI-RS to acquire CSI (730).

[0157] The UE can transmit a CSI report to the base station (740). For the CSI report, the time and frequency resources that the UE can use are controlled by the base station. The CSI (channel state information) can include at least one of a channel quality indicator (CQI), a precoding matrix indicator (PMI), a CSI-RS resource indicator (CRI), an SS / PBCH block resource indicator (SSBRI), a layer indicator (LI), a rank indicator (RI), L1-RSRP, and / or L-SINR.

[0158] The time domain behavior of CSI reporting supports periodic, semi-persistent, and aperiodic. i) Periodic CSI reporting is performed on short PUCCH and long PUCCH. The periodicity and slot offset of periodic CSI reporting can be configured by RRC, and refer to the CSI-ReportConfig IE. ii) SP (semi-periodic) CSI reporting is performed on short PUCCH, long PUCCH, or PUSCH. In case of SP CSI on short / long PUCCH, the periodicity and slot offset are configured by RRC, and CSI reporting is activated / deactivated by separate MAC CE / DCI. In case of SP CSI on PUSCH, the periodicity of SP CSI reporting is configured by RRC, but the slot offset is not configured by RRC, and SP CSI reporting is activated / deactivated by DCI (format 0_1). For SP CSI reporting on PUSCH, a separate RNTI (SP-CSI C-RNTI) is used. The initial CSI reporting timing follows the PUSCH time domain allocation value indicated in the DCI, and subsequent CSI reporting timings follow the cycle set by RRC. DCI format 0_1 ​​includes a CSI request field and can activate / deactivate a specific configured SP-CSI trigger state. SP CSI reporting has the same or similar activation / deactivation mechanism as the data transmission mechanism on the SPS PUSCH.iii) Aperiodic CSI reporting is performed on PUSCH and is triggered by DCI. In this case, information related to the triggering of aperiodic CSI reporting can be transmitted / indicated / configured via MAC-CE. For AP CSI with AP CSI-RS, the AP CSI-RS timing is configured by RRC, and the timing for AP CSI reporting is dynamically controlled by DCI.

[0159] QCL (quasi-co location)

[0160] Two antenna ports are quasi-co-located if the channel properties of one antenna port can be inferred from the channel properties of the other antenna port. The channel properties may include one or more of Delay spread, Doppler spread, Frequency / Doppler shift, Average received power, Received Timing / average delay, and Spatial RX parameters.

[0161] A terminal can configure a list of multiple TCI-State configurations via the upper layer parameter PDSCH-Config. Each TCI-State is associated with one or two DL reference signals and a QCL configuration parameter between the DM-RS port of the PDSCH. The QCL can include qcl-Type1 for the first DL RS and qcl-Type2 for the second DL RS. The QCL type can correspond to one of the following:

[0162] - 'QCL-TypeA': {Doppler shift, Doppler spread, average delay, delay spread}

[0163] - 'QCL-TypeB': {Doppler shift, Doppler spread}

[0164] - 'QCL-TypeC': {Doppler shift, average delay}

[0165] - 'QCL-TypeD': {Spatial Rx parameter}

[0166] M-TRP (multiple-transmission / reception point) related operations

[0167] Figure 8 illustrates multi-TRP transmission. Referring to Figure 8(a), groups of layers transmitting the same CW (codeword) (or TB) correspond to different TRPs. Referring to Figure 8(b), different CWs are transmitted through layer groups of different TRPs. At this time, it can be assumed that the TBs corresponding to CW #1 and CW #2 in the figure are identical. CW #1 and CW #2 each mean that the same TB is converted into different CWs through channel coding, etc. by different TRPs. Therefore, it can be viewed as an example of repeated transmission of the same TB. In the case of Figure 8(b), compared to Figure 8(a), it may have the disadvantage of having a high code rate corresponding to the TB. However, it has the advantage of being able to adjust the code rate or control the modulation order of each CW by indicating different RV (redundancy version) values ​​for encoded bits generated from the same TB depending on the channel environment.

[0168] According to the method exemplified in Figures 8(a) and 8(b), the same TB is repeatedly transmitted through different layer groups, and since each layer group is transmitted by a different TRP / panel, the data reception probability of the terminal can be increased. This is referred to as an SDM (Spatial Division Multiplexing)-based M-TRP URLLC transmission method. Layers belonging to different layer groups are transmitted through DMRS ports belonging to different DMRS CDM groups.

[0169] In addition, although the above-described multiple TRP related content was explained based on the SDM (spatial division multiplexing) method using different layers, it can be extended and applied to the FDM (frequency division multiplexing) method based on different frequency domain resources (e.g., RB / PRB (set) etc.) and / or the TDM (time division multiplexing) method based on different time domain resources (e.g., slots, symbols, sub-symbols etc.).

[0170] MTRP URLLC

[0171] In the methods proposed below, DL MTRP-URLLC means that multiple TRPs transmit the same data / DCI using different layer / time / frequency resources. For example, TRP 1 transmits the same data / DCI on resource 1, and TRP 2 transmits the same data / DCI on resource 2. A UE configured with the DL MTRP-URLLC transmission method receives the same data / DCI using different layer / time / frequency resources. At this time, the UE is instructed by the base station which QCL RS / type (DL TCI state) to use in the layer / time / frequency resource where the same data / DCI is received. For example, if the same data / DCI is received on resource 1 and resource 2, the UE is instructed which DL TCI state is used on resource 1 and which DL TCI state is used on resource 2. Since the UE receives the same data / DCI through both resource 1 and resource 2, high reliability can be achieved. This DL MTRP URLLC can be applied to PDSCH / PDCCH.

[0172] Conversely, UL MTRP-URLLC means that multiple TRPs receive the same data / UCI from a UE using different layer / time / frequency resources. For example, TRP 1 receives the same data / DCI from the UE on resource 1, and TRP 2 receives the same data / DCI from the UE on resource 2, and then shares the received data / DCI through the connected backhaul link between the TRPs. A UE configured with the UL MTRP-URLLC transmission method transmits the same data / UCI using different layer / time / frequency resources. At this time, the UE is instructed by the base station which Tx beam and which Tx power (UL TCI state) to use in the layer / time / frequency resource transmitting the same data / UCI. For example, if the same data / UCI is transmitted on resource 1 and resource 2, the UE is instructed on the UL TCI state used on resource 1 and the UL TCI state used on resource 2. This UL MTRP URLLC can be applied to PUSCH / PUCCH.

[0173] In addition, in the methods proposed below, using (mapping) a specific TCI state (or TCI) when receiving data / DCI / UCI for a certain frequency / time / spatial resource can mean that, in the case of DL, a channel is estimated from DMRS using the QCL type and QCL RS indicated by the corresponding TCI state in the frequency / time / spatial resource, and data / DCI is received / demodulated with the estimated channel. In the case of UL, it can mean that DMRS and data / UCI are transmitted / modulated using the Tx beam and / or Tx power indicated by the corresponding TCI state in the frequency / time / spatial resource.

[0174] The above UL TCI state contains Tx beam or Tx power information of the UE, and may be set to the UE through other parameters such as spatial relation info instead of the TCI state. The UL TCI state may be directly indicated in the UL grant DCI, or may mean spatial relation info of the SRS resource indicated through the SRI field of the UL grant DCI. Or, it may mean the OL Tx power control parameter ( j: index for open loop parameters Po & alpha (maximum 32 parameter value sets per cell), q_d: index of DL RS resource for PL measurement (maximum 4 measurements per cell), l: closed loop power control process index (maximum 2 processes per cell) ) linked to the value indicated through the SRI field of the UL grant DCI.

[0175] On the other hand, MTRP-eMBB means that different data is transmitted using different layers / time / frequency of Multiple TRPs, and a UE configured with the MTRP-eMBB transmission method is instructed to multiple TCI states by DCI, and it is assumed that the data received using the QCL RS of each TCI state is different data.

[0176] Additionally, the UE can determine whether it is MTRP URLLC transmission / reception or MTRP eMBB transmission / reception by using the RNTI for MTRP-URLLC and the RNTI for MTRP-eMBB separately. If the RNTI for URLLC is used and the DCI is CRC masked, it is identified as URLLC transmission, and if the RNTI for eMBB is used and the DCI is CRC masked, it is identified as eMBB transmission. Alternatively, the base station can configure MTRP URLLC transmission / reception or MTRP eMBB transmission / reception to the UE through other new signaling.

[0177] For convenience of explanation, this specification assumes cooperative transmission / reception between two TRPs and applies the proposed method. However, it can also be applied to multi-TRP environments with three or more TRPs, and can be expanded to multi-panel environments. Different TRPs can be recognized by the UE as different TCI states, and when the UE receives / transmits data / DCI / UCI using TCI state 1, it means that the data / DCI / UCI has been received / transmitted from / to TRP 1.

[0178] The proposals in this specification can be utilized in situations where MTRP performs cooperative transmission of PDCCH (repeated transmission or divided transmission of the same PDCCH), and some of the proposals can also be utilized in situations where MTRP performs cooperative transmission of PDSCH or cooperative reception of PUSCH / PUCCH.

[0179] In addition, in the following, the meaning that multiple base stations (i.e. MTRP) repeatedly transmit the same PDCCH may mean that the same DCI was transmitted through multiple PDCCH candidates, and is the same as the meaning that multiple base stations repeatedly transmit the same DCI. The same DCI may mean two DCIs with the same DCI format / size / payload. Alternatively, even if the payloads of two DCIs are different, they can be said to be the same DCI if the scheduling results are the same. For example, the TDRA (time domain resource allocation) field of the DCI relatively determines the slot / symbol positions of the data and the slot / symbol positions of the A / N based on the time point of reception of the DCI. If the DCI received at time n and the DCI received at time n+1 inform the UE of the same scheduling result, the TDRA fields of the two DCIs will be different, and consequently, the DCI payloads will inevitably be different. The number of repetitions R can be directly indicated by the base station to the UE or can be mutually agreed upon. Or, even if the payloads of two DCIs are different and the scheduling results are not the same, if the scheduling result of one DCI is a subset of the scheduling result of the other DCI, they can be said to be the same DCI. For example, if the same data is TDMed and repeatedly transmitted N times, DCI 1 received before the first data indicates data repetition N times, and DCI 2 received after the first data and before the second data indicates data repetition N-1 times. The scheduling data of DCI 2 becomes a subset of the scheduling data of DCI 1, and since both DCIs are scheduling for the same data, they can also be said to be the same DCI in this case.

[0180] Also, in the following, the meaning that multiple base stations (i.e., MTRPs) divide and transmit the same PDCCH may mean, for example, that one DCI is transmitted through one PDCCH candidate, but some resources for which the PDCCH candidate is defined are transmitted by TRP 1 and the remaining resources are transmitted by TRP 2. For example, when TRP 1 and TRP 2 divide and transmit a PDCCH candidate corresponding to an aggregation level m1+m2, the PDCCH candidate is divided into PDCCH candidate 1 corresponding to an aggregation level m1 and PDCCH candidate 2 corresponding to an aggregation level m2, and TRP 1 transmits PDCCH candidate 1 and TRP 2 transmits PDCCH candidate 2 using different time / frequency resources. After receiving PDCCH candidate 1 and PDCCH candidate 2, the UE generates a PDCCH candidate corresponding to an aggregation level m1+m2 and attempts DCI decoding.

[0181] Meanwhile, there may be two implementation methods when the same DCI is transmitted by dividing it into multiple PDCCH candidates.

[0182] First, the DCI payload (control information bits + CRC) is encoded through a single channel encoder (e.g., polar encoder), and the resulting coded bits are divided and transmitted by two TRPs. In this case, the coded bits transmitted by each TRP may encode the entire DCI payload or only a portion of the DCI payload. The second method divides the DCI payload (control information bits + CRC) into two (DCI 1 and DCI 2), and each is encoded through a channel encoder (e.g., polar encoder). Afterwards, the two TRPs transmit the coded bits corresponding to DCI 1 and the coded bits corresponding to DCI 2, respectively.

[0183] Whether the PDCCH is transmitted repeatedly or in segments, it can be understood that the PDCCH is transmitted multiple times across multiple Transmission Occasions (TOs), where TO refers to a specific time / frequency resource unit in which the PDCCH is transmitted. For example, if the PDCCH is transmitted multiple times across slots 1, 2, 3, and 4 (to a specific RB), TO can refer to each slot. If the PDCCH is transmitted multiple times across RB sets 1, 2, 3, and 4 (in a specific slot), TO can refer to each RB set. Or, if the PDCCH is transmitted multiple times across different times and frequencies, TO can refer to each time / frequency resource. In addition, the TCI state used for DMRS channel estimation can be set differently for each TO, and TOs with different TCI states can be assumed to have been transmitted by different TRPs / panels. When multiple base stations transmit a PDCCH repeatedly or in segments, it means that the PDCCH is transmitted across multiple TOs, and the union of the TCI states set for the TOs consists of two or more TCI states. For example, if a PDCCH is transmitted across TOs 1, 2, 3, and 4, TCI states 1, 2, 3, and 4 may be set for TOs 1, 2, 3, and 4 respectively, which means that TRP i cooperatively transmitted the PDCCH on TO i.

[0184] Also, in the following, when a UE repeatedly transmits the same PUSCH so that multiple base stations (i.e., MTRPs) can receive it, it may mean that the same data is transmitted through multiple PUSCHs, and each PUSCH may be optimized for a UL channel of a different TRP. For example, when a UE repeatedly transmits the same data through PUSCH 1 and 2, PUSCH 1 is transmitted using UL TCI state 1 for TRP 1, and link adaptation such as precoder / MCS is also scheduled and transmitted with values ​​optimized for the channel of TRP 1. PUSCH 2 is transmitted using UL TCI state 2 for TRP 2, and link adaptation such as precoder / MCS is also scheduled and transmitted with values ​​optimized for the channel of TRP 2. In this case, the repeatedly transmitted PUSCHs 1 and 2 may be transmitted at different times and may be TDM, FDM, or SDM.

[0185] Also, below, the UE dividing and transmitting the same PUSCH so that multiple base stations (i.e. MTRPs) can receive it means that one data can be transmitted through one PUSCH, but the resources allocated to the PUSCH can be split and transmitted in an optimized manner on the UL channels of different TRPs. For example, if the UE transmits the same data through a 10-symbol PUSCH, the first 5 symbols are transmitted using UL TCI state 1 for TRP 1, and link adaptations such as precoder / MCS are also scheduled and transmitted with values ​​optimized for the channel of TRP 1. The remaining 5 symbols are transmitted using UL TCI state 2 for TRP 2, and link adaptations such as precoder / MCS are also scheduled and transmitted with values ​​optimized for the channel of TRP 2. In the above example, one PUSCH is divided into time resources and transmission toward TRP 1 and transmission toward TRP 2 is TDM, but it can also be transmitted in FDM / SDM manner.

[0186] Similar to PUSCH transmission, PUCCH can also be transmitted repeatedly by the UE for reception by multiple base stations (i.e. MTRP) or by dividing the same PUCCH.

[0187] Antenna Coherency

[0188] Meanwhile, antenna structures can be broadly divided into three types depending on whether coherency between antenna ports can be maintained.

[0189] - Non-coherent: Coherency cannot be maintained between all antenna ports.

[0190] - Partial-coherent: Coherency can be maintained between some antenna ports.

[0191] - Full-coherent: Coherency can be maintained between all antenna ports.

[0192] For 8Tx UL, there can be two partial-coherent types as shown in Fig. 9.

[0193] Figure 9 illustrates an example of an 8Tx partial-coherent antenna configuration. In each of Figures 9 (a) and (b), the dotted lines represent coherent port groups. Ng is the number of coherent port groups.

[0194] Ng=2 means there are two coherency antenna groups (each antenna group consists of four antenna ports), and Ng=4 means there are four coherency antenna groups (each antenna group consists of two antenna ports). Here, antenna groups can also mean antenna panels.

[0195] Ng=2 can be referred to as coherent group level11, and Ng=4 can be referred to as coherent group level12.

[0196] Fig. 10 illustrates another example of an antenna configuration corresponding to 8Tx Partial-coherent level 1. Specifically, compared to Fig. 9(a), Fig. 10 illustrates a case where port grouping according to port index is different in Partial-coherent level 1.

[0197] For reference, in the case of full-coherent TPMI, all ports can be grouped into a single coherent port group, and in the case of non-coherent, there is only one coherent port within a coherent port group. For example, a coherent port group can be a set of ports that maintain coherency from SRS transmission to PUSCH transmission. Each coherent port group can correspond to each panel. And / or, an associated SRS resource or SRS resource set can be individually configured for each coherent port group.

[0198] UL transmission based on 3 Tx antenna port

[0199] NR supports 1, 2, 4, and 8 Tx uplink transmissions. For handheld devices, integrating multiple transmit / receive antennas into a confined space is physically challenging, and even if supported, it is costly. Therefore, a more practical antenna layout needs to be supported, and thus 3-port Tx transmission needs to be considered. For 3-port uplink transmission, codebook-based or non-codebook-based uplink transmission can be considered. This specification specifically proposes methods for codebook-based transmission.

[0200] Figure 11 is an example of the uplink 3Tx antenna layout of a terminal.

[0201] Referring to FIG. 11, the uplink 3Tx antenna ports (hereinafter referred to as ports) of the terminal can be broadly divided into three types. One is a case where all three ports are configured as co-polarization (co-pol) antennas, another is a case where two ports are cross-polarization (X-pol) antenna ports and the remaining port is configured as co-pol. Lastly, there is a case where all three ports are configured from X-pol, but two ports are configured as two complete X-pols and the remaining port is configured as a " / " slant antenna or a "\" slant antenna port among the X-pols.

[0202] In Fig. 11, the X-pol antenna can be configured as one panel, and in this case, antenna coherency can be well maintained for two antenna ports. Here, antenna coherency (or uplink coherent transmission) means whether the phase difference between antennas between SRS transmission and PUSCH transmission in the uplink transmission of the terminal can be maintained, so as to properly reflect the performance for a specific codebook, and the antenna coherency can be configured as a capability of the terminal.

[0203] Proposal 1

[0204] In 3Tx uplink transmission (for codebook based UL), the following three levels of coherency are considered.

[0205] - Full coherency: When all 3 ports are capable of coherent transmission,

[0206] - Partial coherency: When only 2 ports are capable of coherent transmission, for example, in a 2+1 or 1+2 port configuration, 2 ports are capable of coherent transmission.

[0207] - Non-coherency: When no port is capable of coherent transmission, for example, when only 1 port is capable of coherent transmission.

[0208] In Proposal 1, in the case of Partial coherent, for example, as in the second and third ports in the above-mentioned Fig. 11, a 2-port group forms a coherent group, such as the same antenna group (e.g., dotted line), and the other ports are non-coherent with the group.

[0209] Proposal 2

[0210] At least some of the following options may be used to configure a 3Tx Full coherent codebook:

[0211] - Opt 1. Codebook based on phase components that match coherence with the UL 2port codebook and the remaining one port.

[0212] - Opt 2. Length-3 DFT vector based codebook

[0213] - Opt 3. Codebook based on port-wise phase components

[0214] - Opt 4. Pre-defined / configure codebook based on length-3 basis

[0215] - Opt 5. 3-port codebook configuration based on Legacy UL 4-port codebook

[0216] Let's take a closer look at the codebook configuration for each option.

[0217] (1) The codebook according to Opt 1 can be structured as follows.

[0218] (i) Rank1

[0219] For the Rank1 codebook, it takes the form of mathematical expression 1.

[0220] [Mathematical Formula 1]

[0221]

[0222] In mathematical expression 1, b is b∈C 2Х1 It is generated based on the UL 2Tx codebook as a vector. For example, b can be generated as in Equation 2. In Equation 2, the codebook normalization factor is omitted for convenience of explanation.

[0223] [Equation 2]

[0224]

[0225] ρ is a factor for aligning the co-phase with b, and can be configured as an alphabet such as BPSK or QPSK or 8PSK, such as ρ={1,-1} or {1,j,-1,-j}, by pre-determining it through a pre-defined rule or by setting the base station.

[0226] (ii) Rank 2

[0227] For UL 2Tx Rank 2 codebook, b can be based on mathematical expression 3, and in order to maintain orthogonality, a codebook in the form of mathematical expression 4 can be constructed.

[0228] [Equation 3]

[0229]

[0230] [Equation 4]

[0231]

[0232] In mathematical expression 4, the values ​​of x and y can be composed / determined as subsets of, for example, {1, j, -1, -j}.

[0233] (iii) Rank 3

[0234] For Rank 3, due to the lack of UL 2Tx dimension, rank 3 expansion is not possible. Therefore, by borrowing a layer orthogonal projection method for the rank 1 codebook, such as the House-holder transform based approach, Given's rotation based approach, or Gram-Schmidt method, the layer orthogonality procedure can be used to expand the given rank 1 codebook to rank 2 / 3 to construct a codebook. In the above case, the terminal and the base station must know each other's codebook construction method, and for this purpose, the layer orthogonality procedure must be defined in the standard.

[0235] (2) The codebook according to Opt 2 can be structured as follows.

[0236] (i) Rank 1

[0237] For Option 2, it is based on a length-3 DFT codebook that can maintain orthogonality. The Rank1 codebook using this is as shown in Equation 5.

[0238] [Equation 5]

[0239]

[0240] Mathematical expression 5 assumes an oversampling factor of 1, so the total codebook size is 3. To improve codebook performance and construct a larger codebook, the oversampling factor can be increased to 2. In this case, the additionally increased codebook size is as shown in Mathematical expression 6.

[0241] [Equation 6]

[0242]

[0243] The oversampling factor can be set by the base station through RRC, etc., or a pre-agreed value can be used. Looking at the above values, the codebook elements mapped to each port are not integers like QPSK / BPSK, but are expressed as real numbers. This is a problem that occurs when using length-3 DFT, and if the codebook factors are expressed as real numbers rather than integers, the complexity for implementing the codebook may be greater. Therefore, the oversampling factor to be applied / used in the length-3 DFT-based codebook or the length-3 DFT codebook can be set / instructed based on the capability of the terminal.

[0244] (ii) Rank 2

[0245] Compared to other options, the DFT-based codebook is easy to create a rank-2 codebook because each vector is orthogonal (i.e., in the case of Equation 5, the vectors in Equation 5 are orthogonal to each other, and in the case of Equation 6, the vectors in Equation 6 are orthogonal to each other). For example, in the case of the above rank-2 codebook, two of the three candidate vectors in Equation 5 can be selected and constructed as in Equation 7.

[0246] [Equation 7]

[0247]

[0248] Mathematical expression 6 can also be extended / applied to Rank 2 like Mathematical expression 7.

[0249] (iii) Rank 3

[0250] In the case of Rank 3, it can be limited to cases where all three vectors are used, such as in Equation 8 or Equation 9.

[0251] [Equation 8]

[0252]

[0253] [Equation 9]

[0254]

[0255] Since granularity for lower ranks is more important for performance, a codebook can be constructed using a higher oversampling factor only for ranks below a certain level. For example, an oversampling factor of 2 could be applied only to rank 1, while an oversampling factor of 1 could be applied to ranks 2 and 3.

[0256] (3) The codebook according to Opt 3 can be structured as follows.

[0257] The codebook of the above option 3 is [1, x, y] T , and x and y can be pre-determined through a pre-defined rule or determined based on the base station settings. Depending on the alphabet size of the x and y values, it can be a special case of option 1. For example, if x, y = {1, j, -1, -j}, it can be a special case of option 1.

[0258] (4) The codebook according to Opt 4 can be structured as follows.

[0259] For Option 4, a predefined orthogonal set (not the DFT) can be used.

[0260] For example, consider a codebook based on the basis of Equation 10 below, where the normalization factor is 2. Such basis can be agreed upon in advance or configured by the base station. Using this orthogonal basis, ranks 1 / 2 / 3 can be configured using the method described in Option 2 above.

[0261] [Equation 10]

[0262]

[0263] (5) The codebook according to Opt 5 can be structured as follows.

[0264] For Option 5, the legacy 4Tx codebook is used.

[0265]

[0266] For example, Table 7 is a legacy 4Tx UL codebook, and the TPMI index 12-27 is a full coherent codebook. In the case of using the 4Tx-based codebook, a codebook that uses only 3 ports out of the given 4 ports is used for the uplink precoder. In this case, how to map and use 3 ports out of the 4 ports can be agreed upon in advance or set in advance by the base station. For example, ports 1, 2, and 3 can be used, and for example, if the base station indicates TPMI index 27, in the case of 4Tx, [1, -j, -j, -1] T However, the terminal uses this 3 Tx codebook for example [1, -j, -j] T This means that it is recognized and acts as such.

[0267] Option 5 has the advantage of being able to reuse existing codebook designs without requiring a separate codebook design. However, this method presents difficulties in extending to rank 2 / 3. This is because orthogonality, which is maintained at length-4, becomes difficult to maintain if arbitrarily reduced to length-3. Therefore, this option can only be operated / configured / supported at rank 1.

[0268] As can be seen in the above proposal 2, for the rank 1 codebook, the option 1 / 3 / 5 method that can utilize the alphabet granularity of the existing codebook such as QPSK / BSPK can be used, and in the case of the above options, since it is not easy to expand to rank 2 / 3, if the above option is considered as a UL 3Tx codebook, the full coherent case is supported only for rank 1. For the remaining ranks 2 and / or 3, they can be configured by combining / combining based on the partial coherent and / or non-coherent codebook configuration method described below.

[0269] Proposal 3

[0270] For the 3Tx Partial coherent codebook, a codebook configuration such as Equation 11 can be considered.

[0271] [Equation 11]

[0272]

[0273] For the partial coherent codebook of Proposal 3, 2-port partial coherency of 2+1 and 2-port partial coherency of 1+2 can be considered, as shown in Fig. 11. Equation 11 exemplifies 2+1 for convenience of explanation, and an example of 1+2 is as shown in Equation 12.

[0274] [Equation 12]

[0275]

[0276] The above example is an example of row permutation, and the 2+1 and 1+2 port mapping orders are agreed upon in advance, so that one of the two codebooks can be set / instructed to the terminal based on the codebook configuration or the terminal's capability report.

[0277] In the above proposal 3, for x and / or y, similar to proposal 2, it can be configured in the form of eg, x, y={1, j, -1, -j}, and for codebook flexibility, the alphabet size can be set / indicated by the base station. Or [1, x] T , [1, y] T , and / or [(1, x) T (1, y) T ] For the components, it can be configured as a legacy UL 2Tx codebook for option 1 of proposal 2.

[0278] Proposal 4

[0279] For 3Tx Non-coherent codebook, a codebook configuration such as Equation 13 can be considered.

[0280] [Equation 13]

[0281]

[0282] For the above codebook, all ranks are normalized to 1 / √3 (1 / root (3)).

[0283] Proposal 4 is a non-coherent codebook configuration method, which can be configured with a port selection codebook like the legacy configuration method.

[0284] In the case of the non-coherent codebook in Proposal 4, since the terminal's port coherence is non-coherent, the phase between each port cannot be maintained. Therefore, only the port selection codebook mentioned above can be used. Furthermore, in codebook-based UL, each PUSCH port transmits with power equally distributed among the ports. Table 8 below is an excerpt from TS 38.213.

[0285]

[0286] However, when performing multi-layer transmission, allocating more power to layers with higher SINR improves performance and throughput. Therefore, the following codebook design and PUSCH power control are proposed.

[0287] (1) Proposal 4-1

[0288] For 3Tx Non-coherent codebook, consider the codebook configuration method of the following mathematical expression 14.

[0289] [Equation 14]

[0290]

[0291] Here, for x, y, z, (based on the capability of the terminal), they can be indicated / set to the values ​​in Table 9.

[0292]

[0293] Table 9 is an example where the values ​​(amplitude) corresponding to x, y, and z are represented as 2 bits. It is obvious that other bit-widths (e.g., 1-bit or 3-bit) and / or other values / granularities can also be used. Also, Table 9 above may include all values ​​>1, <1. Alternatively, one port can be considered as a reference port and only values ​​less than or equal to 1 can be used. As an example, consider Table 10 below.

[0294]

[0295] However, in the above method, the terminal cannot know which port is the reference port. To solve this problem, a method of fixing the reference port to a specific port can be considered. For example, the first port (e.g., PUSCH port 1000) can be assumed / promised / configured as the reference port. In this case, for ports with a value greater than the corresponding port, the upper bound can be indicated / configured with index 3 (value of 1). In addition, for ports with a value smaller than this, the terminal can be indicated / configured with the values ​​of the index 0, 1, 2, etc. Another method can additionally indicate which port is the reference port. As an example of the reference port indication, it is necessary to indicate / configure a strongest port indicator, etc. Or, like the layer indicator of DL, when UL LI is introduced, the port corresponding to the LI can be defined as the strongest port.

[0296] In contrast to allocating more power to the strong layer, one could also consider allocating more power to the worst layer. While this approach may be somewhat disadvantageous in terms of sum rate compared to allocating more power to the best layer, it has the advantage of improving the performance of the worst layer, thereby improving minimum performance. From this perspective, an indicator for the worst layer could be introduced, and power allocation for performance enhancement could be set / directed based on the aforementioned method.

[0297] Alternatively, in addition to the method of indicating the strongest / worst layer, the base station can indicate / configure information on layer ordering or port re-ordering for UL transmission to the terminal based on the SINR / SNR / RSRP level per port / layer, and based on this, the terminal can re-index the SRS port and / or PUSCH port to use for UL transmission. For example, if the base station indicates the layer (or port) order as 2-1-3 to the terminal, the terminal can configure the PUSCH port as 2-1-3 according to the order and transmit PUSCH. In this case, it can be promised that the strongest / worst port / layer information is set to the first port / layer that is re-ordered, and in this case, the amplitude is always set in the direction of decreasing or increasing, as shown in Table 10. The advantage of this method is that it can reduce the implementation complexity of the base station / terminal (related to power allocation).

[0298] In NR, the base station instructs the terminal to use the max rank restriction and codebook subset restriction via RRC to reduce the payload and ensure effective scheduling. In addition, the base station can instruct / configure the terminal to specify a restriction on the amplitude. For example, the power that the terminal should not use can be specified / configured using a 4-bit bitmap for the 4 codepoints of the amplitude table. Alternatively, this can be specified using 4 2-bit codepoints (00, 01, 10, 11). Based on the amplitude restriction, the payload related to the final amplitude can be determined. If 2 bits are required for the 4 amplitude indications, if only 2 codepoints are valid for the restriction, only 1 bit can be used for the 2 amplitude indications. In addition to the restriction indicated by the base station, the terminal can report information about the available (unavailable) or preferred amplitudes in the (predefined) amplitude table based on its capability. The base station can use amplitude instructions based on these reports from the terminal.

[0299] In the case of the codebook of Rank 3 in Equation 14, it can correspond to (b) or (c) of Fig. 11, two ports correspond to one panel, and only the remaining port can be mapped to a different panel. Therefore, ports belonging to the same panel have the same power per port, and the value of x can be set / indicated based on the examples in Tables 9 / 10. With this characteristic, the Rank 2 codebook can also be considered to have equal power for a specific port group, and different power only for the remaining port groups. For example, ports 1 and 2 can be considered to be the same panel, and port 3 can be assumed to correspond to a different panel. Then, the rank 2 codebook can be simplified as in Equation 15. Which ports correspond to which panels can be based on the capabilities of the terminal.

[0300] [Equation 15]

[0301]

[0302] For the codebook instruction method based on Proposal 4-1, the following instructions / settings can be followed.

[0303] (i) Option 1. Joint indication of TRI / TPMI (including matrix and / or amplitude) (One field)

[0304] (ii) Option 2. Separate indication of TRI / TPMI and amplitude (two fields)

[0305] (iii) Option 3. Separate indication of TRI and, selection matrix and amplitude.

[0306] For the above option 1, for example, a codebook subset containing multiple amplitudes is defined, and the base station instructs TRI + TPMI in the entire codebook subset. Mathematical expression 16 below represents an example codebook subset of option 1.

[0307] [Equation 16]

[0308]

[0309] For the above codebook, 15 codepoints can be indicated from rank 1 to rank 3 using a maximum of 4 bits.

[0310] For Option 2, rank TRI / TPMI, etc. are indicated as max 3 bits for the codebook of mathematical expression 17 below (first field), and amplitude is indicated as a separate field (second field).

[0311] [Equation 17]

[0312]

[0313] If a codebook without different amplitude, such as rank 1, is indicated as TRI / TPMI, the terminal ignores the indication for amplitude.

[0314] For Option 3, TRI is indicated separately (first field) for Option 2, and the components for TPMI + amplitude are indicated in one field (second field). In this case, the size of the second field is determined based on the rank with the largest payload among all ranks.

[0315] For normalization of the codebook based on Proposal 4-1, the following can be considered.

[0316] - Option 1. Normalize to 1 / √3 for all ranks.

[0317] - Option 2. Normalize the codebook matrix to 1.

[0318] For the above option 1, the legacy operation is performed by PUSCH power control for each port. For option 2, the power of all elements is normalized to the sum of their powers to align with PUSCH power control. For example, a normalization factor such as Equation 18 can be considered in the rank 2-3 codebook.

[0319] [Equation 18]

[0320]

[0321] In the case of a terminal that can have different power per layer / port, it can generally be a high-end terminal with a large power amplifier range. Therefore, in the case of the terminal, the power capability per port can be reported as a UE capability. Here, the power capability can be the max rated PA per antenna port (e.g., for PC3, 23dBm, 20dBm, 18.23dBm), or information on the power ratio that can be supported between ports / panels. For example, it can be 1: 1 / √2 or 1: 1 / √3. Based on the reported information of the terminal, the base station instructs / sets the power ratio between ports to the terminal based on the amplitude information of Proposal 4-1.

[0322] Then, the terminal transmits power P^PUSCH,b,f,c(i,j,q d ,l) linear value of P^PUSCH,b,f,c(i,j,q) d,l) is first calculated. This value is scaled to 1, and the power is split and transmitted for each port according to the power ratio. For example, it can operate as shown in Table 11.

[0323]

[0324] (2) Proposal 4-2

[0325] For 3Tx UL, even though it is a non-coherent codebook, different levels of codebook subsets can be specified and set / applied to the terminal.

[0326] The purpose of Proposal 4-2 is to reduce the payload and improve terminal implementation convenience compared to the codebook subset of Proposal 4. For example, if non-coherent codebook1 is defined as in Equation 19, then non-coherent codebook2 can be defined as in Equation 20.

[0327] [Equation 19]

[0328]

[0329] [Equation 20]

[0330]

[0331] Non-coherent codebook2 has the advantage of reducing the maximum bit-width to 2 bits and reducing implementation complexity by reducing the number of codepoints. Therefore, non-coherent codebook2 can be configured for UEs with slightly lower capabilities, such as the RedCap UE.

[0332] (3) Proposal 4-3

[0333] In the non-coherent codebook of Proposal 4, the remaining codepoints can be used to indicate / configure codebooks with different port numbers and / or full power mode / fallback mode for full power transmission purposes.

[0334] In case of Proposal 4-3, if the 3Tx non-coherent codebook cannot support 3Tx full power operation (e.g., full power mode 1 and 2), there may be an issue of insufficient UL coverage. Therefore, the remaining reserved state of the non-coherent codebook indicated by max 3 bits (in case of max rank 3, there is a total of 7 states, so there is a total of 1 reserved state) can be used to indicate the codebook and / or full power mode of another port (e.g., 2Tx). For example, the purpose of using 3Tx is to increase UL throughput compared to 2Tx, but if full power mode is not supported in 3Tx, coverage may be insufficient compared to when performing 2Tx full power operation. Therefore, to this end, even though it is configured as 3Tx, it can be configured / instructed to fallback to 2Tx to support full power operation.

[0335] For example, for one remaining reserved state(s), a TPMI of 2Tx full power mode 1, e.g., Equation 21, can be directed to full power mode 2.

[0336] [Equation 21]

[0337]

[0338] When the base station indicates the reserved state(s), the terminal falls back to 2Tx UL and performs the corresponding codebook and / or full power mode transmission.

[0339] As described above, the rank 1 codebook can be configured by the base station based on the coherent capability of full and / or partial and / or non-coherent, and can be configured to a specific codebook / codebook subset. However, as described above, for a specific full coherent codebook (e.g., option 1 / 3 / 4 / 5 of proposal 2), it is not easy to extend to ranks 2 and 3. In this case, even if the terminal reports full coherent through capability reporting and the base station configures the codebook / codebook subset, for ranks 2 and 3, the rank-2 and / or 3 codebook can be configured solely or in combination with all or part of option 2 of proposal 2 or proposals 3 / 4. For example, a characteristic of the full coherent is a codebook / codebook subset that can appear only in a specific rank.

[0340] Proposal 5

[0341] To support 3Tx codebook based UL, the following SRS configuration methods can be considered.

[0342] - Option 1: 3 port SRS resources can be determined / transmitted for UL transmission based on 3 Tx codebook, and the 4 port SRS resource mapping / transmission method can be reused for such SRS transmission. For example, even if a terminal is scheduled with a 4 port SRS resource, the terminal can understand and operate that the SRS resource is used as a 3 Tx codebook based UL by using the SRI field or a new field / indicator in the DCI.

[0343] - Option 2: Using one or more SRI fields or new fields / indicators in DCI, indicate multiple SRS resources (e.g., 2+1 or 1+1+1), and use the number of ports that aggregate the SRS resources (3 ports in the example above) for PUSCH transmission.

[0344] As an example of Proposal 5, existing legacy SRS resources can be reused without creating a 3-port SRS resource. For Option 1, the 4-port resource can be utilized as is, but in the case of a 3-port capable UE, only a 3-port can be configured with a subset of the resource when operating the 3-port. For example, (i) in a situation where 4 ports are configured / multiplexed only by CS value shift, the UE can perform SRS sequence generation for each of the 3 ports by utilizing only 3 CS values ​​out of the 4 CS values, and / or (ii) in a situation where 4 ports are configured / multiplexed by a combination of CS values ​​and comb offsets, the UE can configure 2 combs using 2 comb offsets, but use only one (same) CS value for one of the 2 combs, thereby performing SRS sequence generation / mapping for each of the 3 ports. That is, one Comb can support 1 port configuration / multiplexing through 1 CS value, and another Comb can support 2 ports configuration / multiplexing through 2 CS values. Therefore, a total of 3 ports can be configured / multiplexed for a total of 2 Combs.

[0345] Alternatively, you can configure 3 ports by always excluding the last / first SRS port (in port order) among the 4 ports.

[0346] In this way, SRS sequence generation and resource mapping are performed for a total of 4 SRS ports, but 3-port SRS transmission can be performed by not actually performing SRS sequence generation and resource mapping for one SRS port among the 4 SRS ports. Since one of the 4 ports is not used and is muted, there may be a disadvantage in that some resources are not used, but there may be an advantage in that implementation is easy by reusing the existing 4-port method. The port for which SRS sequence generation and resource mapping are omitted may be the last port among the 4 SRS ports.

[0347] Option 2 has the advantage of improving resource flexibility. In particular, to prevent performance degradation that occurs when aggregated ports overlap (in the frequency domain) or are excessively spaced apart in the time domain, specific aggregated SRS resources may not overlap, or a minimum / maximum gap (e.g., X symbol / slot) may be defined between the aggregated SRS resources. In particular, for option 2, multiple SRI fields introduced for MTRP uplink transmission can be reused to indicate each SRS aggregation resource. When multiple SRS resources are used for the port aggregation, the aggregation ordering can be configured in order from the lowest / highest index SRS resource (or aggregated in the order of indicated resources).

[0348] The above suggestions 1 / 2 / 3 / 4 / 5 can be used alone or in combination.

[0349] Figure 12 illustrates an implementation example of the operation of a network and a terminal according to one embodiment.

[0350] Referring to FIG. 12, the terminal may receive at least one RRC signaling from the network (A05). The RRC signaling may include an SRS configuration. The SRS configuration may be configured, for example, according to the SRS-Config IE described in Table 6. However, the number of SRS antenna ports (nrofSRS-Ports) in the SRS resource (SRS-Resource) configuration may be set to 3.

[0351] The terminal can generate an SRS sequence based on the SRS configuration (A10). Based on the number of the plurality of SRS antenna ports being 3, the terminal can perform SRS sequence generation for only a total of 3 SRS antenna ports based on the SRS sequence generation method defined for 4 SRS antenna ports. Table 12 is an excerpt of the SRS sequence generation method defined in the existing NR standard TS38.211, which supports up to 4 SRS antenna ports.

[0352]

[0353] The terminal follows the SRS sequence generation method defined in Table 12, assuming four antenna ports, for SRS transmission through three antenna ports, but may omit SRS sequence generation for the fourth (last) SRS antenna port.

[0354] The terminal can perform SRS resource mapping based on the SRS configuration (A15). The terminal can map the SRS sequence generated in step A10 to three antenna ports. Based on the number of the plurality of SRS antenna ports being three, the terminal can perform the SRS resource mapping only for a total of three SRS antenna ports based on the SRS resource mapping method defined for four SRS antenna ports. Table 13 is an excerpt of the SRS resource mapping method defined in the existing NR standard TS38.211, which supports up to four SRS antenna ports.

[0355]

[0356]

[0357] The terminal follows the SRS resource mapping method defined in Table 13, assuming four antenna ports, for SRS transmission through three antenna ports, but SRS resource mapping for the fourth (last) SRS antenna port may be omitted.

[0358] The terminal can perform codebook-based UL signal transmission through three antenna ports (A20). The UL signal may include at least one of the previously generated / mapped SRS and PUSCH. The codebook used for precoding the PUSCH signal may be configured based on Equation 13.

[0359] The network can perform demodulation (A25) and decoding (A30) on the UL signal.

[0360] Fig. 13 illustrates an implementation example of the operation of a terminal in a wireless communication system according to one embodiment.

[0361] Referring to FIG. 13, the terminal can receive SRS (sounding reference signal) settings through upper layer signaling (B05).

[0362] The terminal can perform SRS resource mapping for multiple SRS antenna ports based on the above SRS settings (B10).

[0363] The terminal can transmit SRS through the plurality of SRS antenna ports based on the SRS resource mapping (B15).

[0364] Based on the number of the plurality of SRS antenna ports being 3, the terminal can perform the SRS resource mapping based on an SRS resource mapping method defined for 4 SRS antenna ports, and perform the SRS transmission by muting the last SRS port among the 4 SRS antenna ports.

[0365] The above terminal can receive DCI (downlink control information) instructing to transmit the SRS through three SRS antenna ports.

[0366] The above terminal can transmit a PUSCH (physical uplink control channel) based on a non-coherent codebook supporting three antenna ports.

[0367] For example, the non-coherent codebook may include precoding matrices constructed based on Equation 13 for each rank. The precoding matrices of Equation 13 may be normalized to 1 / √3.

[0368] For example, the non-coherent codebook may include precoding matrices constructed based on mathematical expression 14 for each rank.

[0369] The x, y, and z values ​​of the above mathematical expression 14 may be variables given through network signaling.

[0370] The above network signaling includes a 2-bit index, and the 2-bit index can indicate the x, y, and z values ​​based on Table 9.

[0371] One of the three antenna ports for the above PUSCH can be set as a reference antenna port.

[0372] The above network signaling may indicate the x, y and z values ​​based on the reference antenna port.

[0373] The above terminal can receive information indicating the above reference antenna port.

[0374] The above reference antenna port may be an antenna port linked to an uplink layer indicator included in DCI (downlink control information) that schedules the PUSCH.

[0375] FIG. 14 illustrates an implementation example of the operation of a base station in a wireless communication system according to one embodiment.

[0376] Referring to FIG. 14, the base station can transmit a sounding reference signal (SRS) setting through upper layer signaling (C05).

[0377] The base station can receive SRS transmitted through multiple SRS antenna ports based on the above SRS settings (C10).

[0378] Based on the number of the above-mentioned multiple SRS antenna ports being 3, the base station can receive the SRS based on an SRS resource mapping method defined for four SRS antenna ports. The last SRS port among the four SRS antenna ports can be muted.

[0379] The base station can transmit DCI (downlink control information) to the terminal instructing the terminal to transmit the SRS through three SRS antenna ports.

[0380] The above base station can receive a PUSCH (physical uplink control channel) based on a non-coherent codebook supporting three antenna ports.

[0381] For example, the non-coherent codebook may include precoding matrices constructed based on Equation 13 for each rank. The precoding matrices of Equation 13 may be normalized to 1 / √3.

[0382] For example, the non-coherent codebook may include precoding matrices constructed based on mathematical expression 14 for each rank.

[0383] The x, y, and z values ​​of the above mathematical expression 14 may be variables indicated through network signaling.

[0384] The above network signaling includes a 2-bit index, and the 2-bit index can indicate the x, y, and z values ​​based on Table 9.

[0385] One of the three antenna ports for the above PUSCH can be set as a reference antenna port.

[0386] The above network signaling may indicate the x, y and z values ​​based on the reference antenna port.

[0387] The base station can transmit information indicating the reference antenna port to the terminal.

[0388] The above reference antenna port may be an antenna port linked to an uplink layer indicator included in DCI (downlink control information) that schedules the PUSCH.

[0389] Fig. 15 illustrates a communication system (1) applicable to this embodiment.

[0390] Referring to FIG. 15, a communication system (1) includes a wireless device, a base station, and a network. Here, the wireless device refers to a device that performs communication using a wireless access technology (e.g., 5G NR (New RAT), LTE (Long Term Evolution)) and may be referred to as a communication / wireless / 5G device. Although not limited thereto, the wireless device may include a robot (100a), a vehicle (100b-1, 100b-2), an XR (eXtended Reality) device (100c), a hand-held device (100d), a home appliance (100e), an IoT (Internet of Things) device (100f), and an AI device / server (400). For example, the vehicle may include a vehicle equipped with a wireless communication function, an autonomous vehicle, a vehicle capable of performing vehicle-to-vehicle communication, etc. Here, the vehicle may include an Unmanned Aerial Vehicle (UAV) (e.g., a drone). XR devices include AR (Augmented Reality) / VR (Virtual Reality) / MR (Mixed Reality) devices, and can be implemented in the form of HMD (Head-Mounted Device), HUD (Head-Up Display) installed in a vehicle, television, smartphone, computer, wearable device, home appliance, digital signage, vehicle, robot, etc. Mobile devices can include smartphone, smart pad, wearable device (e.g., smart watch, smart glass), computer (e.g., laptop, etc.), etc. Home appliances can include TV, refrigerator, washing machine, etc. IoT devices can include sensors, smart meters, etc. For example, base stations and networks can also be implemented as wireless devices, and a specific wireless device (200a) can act as a base station / network node to other wireless devices.

[0391] Wireless devices (100a to 100f) can be connected to a network (300) via a base station (200). Artificial Intelligence (AI) technology can be applied to the wireless devices (100a to 100f), and the wireless devices (100a to 100f) can be connected to an AI server (400) via the network (300). The network (300) can be configured using a 3G network, a 4G (e.g., LTE) network, a 5G (e.g., NR) network, etc. The wireless devices (100a to 100f) can communicate with each other via the base station (200) / network (300), but can also communicate directly (e.g., sidelink communication) without going through the base station / network. For example, vehicles (100b-1, 100b-2) can communicate directly (e.g., V2V (Vehicle to Vehicle) / V2X (Vehicle to Everything) communication). In addition, IoT devices (e.g., sensors) can communicate directly with other IoT devices (e.g., sensors) or other wireless devices (100a to 100f).

[0392] Wireless communication / connection (150a, 150b, 150c) can be established between wireless devices (100a~100f) / base stations (200), and base stations (200) / base stations (200). Here, wireless communication / connection can be achieved through various wireless access technologies (e.g., 5G NR) such as uplink / downlink communication (150a), sidelink communication (150b) (or D2D communication), and communication between base stations (150c) (e.g., relay, IAB (Integrated Access Backhaul). Through wireless communication / connection (150a, 150b, 150c), wireless devices and base stations / wireless devices, and base stations and base stations can transmit / receive wireless signals to each other. For example, wireless communication / connection (150a, 150b, 150c) can transmit / receive signals through various physical channels. To this end, at least some of various configuration information setting processes for transmitting / receiving wireless signals, various signal processing processes (e.g., channel encoding / decoding, modulation / demodulation, resource mapping / demapping, etc.), and resource allocation processes can be performed based on various proposals of the present invention.

[0393] Fig. 16 illustrates a wireless device that can be applied to this embodiment.

[0394] Referring to FIG. 16, the first wireless device (100) and the second wireless device (200) can transmit and receive wireless signals through various wireless access technologies (e.g., LTE, NR). Here, {the first wireless device (100), the second wireless device (200)} can correspond to {the wireless device (100x), the base station (200)} and / or {the wireless device (100x), the wireless device (100x)} of FIG. 15.

[0395] A first wireless device (100) includes one or more processors (102) and one or more memories (104), and may further include one or more transceivers (106) and / or one or more antennas (108). The processor (102) controls the memories (104) and / or the transceivers (106), and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in this document. For example, the processor (102) may process information in the memory (104) to generate first information / signal, and then transmit a wireless signal including the first information / signal via the transceiver (106). In addition, the processor (102) may receive a wireless signal including second information / signal via the transceiver (106), and then store information obtained from signal processing of the second information / signal in the memory (104). The memory (104) may be connected to the processor (102) and may store various information related to the operation of the processor (102). For example, the memory (104) may perform some or all of the processes controlled by the processor (102), or may store software code including commands for performing the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document. Here, the processor (102) and the memory (104) may be part of a communication modem / circuit / chip designed to implement a wireless communication technology (e.g., LTE, NR). The transceiver (106) may be connected to the processor (102) and may transmit and / or receive wireless signals via one or more antennas (108). The transceiver (106) may include a transmitter and / or a receiver. The transceiver (106) may be used interchangeably with an RF (Radio Frequency) unit. In the present invention, a wireless device may also mean a communication modem / circuit / chip.

[0396] The second wireless device (200) includes one or more processors (202), one or more memories (204), and may further include one or more transceivers (206) and / or one or more antennas (208). The processor (202) controls the memories (204) and / or the transceivers (206), and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in this document. For example, the processor (202) may process information in the memory (204) to generate third information / signals, and then transmit a wireless signal including the third information / signals via the transceivers (206). Furthermore, the processor (202) may receive a wireless signal including fourth information / signals via the transceivers (206), and then store information obtained from signal processing of the fourth information / signals in the memory (204). The memory (204) may be connected to the processor (202) and may store various information related to the operation of the processor (202). For example, the memory (204) may perform some or all of the processes controlled by the processor (202), or may store software code including commands for performing the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document. Here, the processor (202) and the memory (204) may be part of a communication modem / circuit / chip designed to implement wireless communication technology (e.g., LTE, NR). The transceiver (206) may be connected to the processor (202) and may transmit and / or receive wireless signals via one or more antennas (208). The transceiver (206) may include a transmitter and / or a receiver. The transceiver (206) may be used interchangeably with an RF unit. In the present invention, a wireless device may also mean a communication modem / circuit / chip.

[0397] Hereinafter, the hardware elements of the wireless device (100, 200) will be described in more detail. Although not limited thereto, one or more protocol layers may be implemented by one or more processors (102, 202). For example, one or more processors (102, 202) may implement one or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP, RRC, SDAP). One or more processors (102, 202) may generate one or more Protocol Data Units (PDUs) and / or one or more Service Data Units (SDUs) according to the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document. One or more processors (102, 202) may generate messages, control information, data, or information according to the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in this document. One or more processors (102, 202) can generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data or information according to the functions, procedures, proposals and / or methods disclosed herein, and provide the signals to one or more transceivers (106, 206). One or more processors (102, 202) can receive signals (e.g., baseband signals) from one or more transceivers (106, 206) and obtain PDUs, SDUs, messages, control information, data or information according to the descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed herein.

[0398] One or more processors (102, 202) may be referred to as a controller, a microcontroller, a microprocessor, or a microcomputer. One or more processors (102, 202) may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more Application Specific Integrated Circuits (ASICs), one or more Digital Signal Processors (DSPs), one or more Digital Signal Processing Devices (DSPDs), one or more Programmable Logic Devices (PLDs), or one or more Field Programmable Gate Arrays (FPGAs) may be included in one or more processors (102, 202). The descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in this document may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, etc. The descriptions, functions, procedures, suggestions, methods and / or operation flowcharts disclosed in this document may be implemented using firmware or software configured to perform one or more processors (102, 202) or stored in one or more memories (104, 204) and executed by one or more processors (102, 202). The descriptions, functions, procedures, suggestions, methods and / or operation flowcharts disclosed in this document may be implemented using firmware or software in the form of codes, instructions and / or sets of instructions.

[0399] One or more memories (104, 204) may be coupled to one or more processors (102, 202) and may store various forms of data, signals, messages, information, programs, codes, instructions, and / or commands. The one or more memories (104, 204) may be configured as ROM, RAM, EPROM, flash memory, hard drives, registers, cache memory, computer-readable storage media, and / or combinations thereof. The one or more memories (104, 204) may be located internally and / or externally to the one or more processors (102, 202). Additionally, the one or more memories (104, 204) may be coupled to the one or more processors (102, 202) via various technologies, such as wired or wireless connections.

[0400] One or more transceivers (106, 206) can transmit user data, control information, wireless signals / channels, etc., as mentioned in the methods and / or flowcharts of this document, to one or more other devices. One or more transceivers (106, 206) can receive user data, control information, wireless signals / channels, etc., as mentioned in the descriptions, functions, procedures, proposals, methods and / or flowcharts of this document, from one or more other devices. For example, one or more transceivers (106, 206) can be connected to one or more processors (102, 202) and can transmit and receive wireless signals. For example, one or more processors (102, 202) can control one or more transceivers (106, 206) to transmit user data, control information, or wireless signals to one or more other devices. Additionally, one or more processors (102, 202) may control one or more transceivers (106, 206) to receive user data, control information, or wireless signals from one or more other devices. Additionally, one or more transceivers (106, 206) may be coupled to one or more antennas (108, 208), and one or more transceivers (106, 206) may be configured to transmit and receive user data, control information, wireless signals / channels, or the like, as referred to in the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed herein, via one or more antennas (108, 208). In this document, one or more antennas may be multiple physical antennas or multiple logical antennas (e.g., antenna ports). One or more transceivers (106, 206) can convert received user data, control information, wireless signals / channels, etc. from RF band signals to baseband signals in order to process the received user data, control information, wireless signals / channels, etc. using one or more processors (102, 202).One or more transceivers (106, 206) may convert user data, control information, wireless signals / channels, etc. processed by one or more processors (102, 202) from baseband signals to RF band signals. For this purpose, one or more transceivers (106, 206) may include an (analog) oscillator and / or filter.

[0401] Figure 17 illustrates another example of a wireless device applicable to this embodiment. The wireless device may be implemented in various forms depending on the use case / service (see Figure 15).

[0402] Referring to FIG. 17, the wireless device (100, 200) corresponds to the wireless device (100, 200) of FIG. 16 and may be composed of various elements, components, units / units, and / or modules. For example, the wireless device (100, 200) may include a communication unit (110), a control unit (120), a memory unit (130), and an additional element (140). The communication unit may include a communication circuit (112) and a transceiver(s) (114). For example, the communication circuit (112) may include one or more processors (102, 202) and / or one or more memories (104, 204) of FIG. 16. For example, the transceiver(s) (114) may include one or more transceivers (106, 206) and / or one or more antennas (108, 208) of FIG. 16. The control unit (120) is electrically connected to the communication unit (110), the memory unit (130), and the additional elements (140) and controls the overall operation of the wireless device. For example, the control unit (120) may control the electrical / mechanical operation of the wireless device based on the program / code / command / information stored in the memory unit (130). In addition, the control unit (120) may transmit information stored in the memory unit (130) to an external device (e.g., another communication device) via a wireless / wired interface through the communication unit (110), or store information received from an external device (e.g., another communication device) via a wireless / wired interface in the memory unit (130).

[0403] The additional element (140) may be configured in various ways depending on the type of the wireless device. For example, the additional element (140) may include at least one of a power unit / battery, an input / output unit (I / O unit), a driving unit, and a computing unit. Although not limited thereto, the wireless device may be implemented in the form of a robot (Fig. 15, 100a), a vehicle (Fig. 15, 100b-1, 100b-2), an XR device (Fig. 15, 100c), a portable device (Fig. 15, 100d), a home appliance (Fig. 15, 100e), an IoT device (Fig. 15, 100f), a digital broadcasting terminal, a hologram device, a public safety device, an MTC device, a medical device, a fintech device (or a financial device), a security device, a climate / environmental device, an AI server / device (Fig. 15, 400), a base station (Fig. 15, 200), a network node, etc. Wireless devices may be mobile or stationary depending on the use / service.

[0404] In FIG. 17, various elements, components, units / parts, and / or modules within the wireless device (100, 200) may be entirely interconnected via a wired interface, or at least some may be wirelessly connected via a communication unit (110). For example, within the wireless device (100, 200), the control unit (120) and the communication unit (110) may be wired, and the control unit (120) and a first unit (e.g., 130, 140) may be wirelessly connected via the communication unit (110). In addition, each element, component, unit / part, and / or module within the wireless device (100, 200) may further include one or more elements. For example, the control unit (120) may be composed of a set of one or more processors. For example, the control unit (120) may be composed of a set of a communication control processor, an application processor, an electronic control unit (ECU), a graphics processing processor, a memory control processor, etc. As another example, the memory unit (130) may be composed of RAM (Random Access Memory), DRAM (Dynamic RAM), ROM (Read Only Memory), flash memory, volatile memory, non-volatile memory, and / or a combination thereof.

[0405] Figure 18 illustrates a vehicle or autonomous vehicle applicable to this embodiment. The vehicle or autonomous vehicle may be implemented as a mobile robot, a car, a train, a manned or unmanned aerial vehicle (AV), a ship, etc.

[0406] Referring to FIG. 18, a vehicle or autonomous vehicle (100) may include an antenna unit (108), a communication unit (110), a control unit (120), a driving unit (140a), a power supply unit (140b), a sensor unit (140c), and an autonomous driving unit (140d). The antenna unit (108) may be configured as a part of the communication unit (110). Blocks 110 / 130 / 140a to 140d correspond to blocks 110 / 130 / 140 of FIG. 17, respectively.

[0407] The communication unit (110) can transmit and receive signals (e.g., data, control signals, etc.) with external devices such as other vehicles, base stations (e.g., base stations, road side units, etc.), and servers. The control unit (120) can control elements of the vehicle or autonomous vehicle (100) to perform various operations. The control unit (120) can include an ECU (Electronic Control Unit). The drive unit (140a) can drive the vehicle or autonomous vehicle (100) on the ground. The drive unit (140a) can include an engine, a motor, a power train, wheels, brakes, a steering device, etc. The power supply unit (140b) supplies power to the vehicle or autonomous vehicle (100) and can include a wired / wireless charging circuit, a battery, etc. The sensor unit (140c) can obtain vehicle status, surrounding environment information, user information, etc. The sensor unit (140c) may include an IMU (inertial measurement unit) sensor, a collision sensor, a wheel sensor, a speed sensor, an incline sensor, a weight detection sensor, a heading sensor, a position module, a vehicle forward / backward sensor, a battery sensor, a fuel sensor, a tire sensor, a steering sensor, a temperature sensor, a humidity sensor, an ultrasonic sensor, an illuminance sensor, a pedal position sensor, etc. The autonomous driving unit (140d) may implement a technology for maintaining a driving lane, a technology for automatically controlling speed such as adaptive cruise control, a technology for automatically driving along a set path, a technology for automatically setting a path and driving when a destination is set, etc.

[0408] For example, the communication unit (110) can receive map data, traffic information data, etc. from an external server. The autonomous driving unit (140d) can generate an autonomous driving route and driving plan based on the acquired data. The control unit (120) can control the drive unit (140a) so that the vehicle or autonomous vehicle (100) moves along the autonomous driving route according to the driving plan (e.g., speed / direction control). During autonomous driving, the communication unit (110) can irregularly / periodically acquire the latest traffic information data from an external server and can acquire surrounding traffic information data from surrounding vehicles. In addition, during autonomous driving, the sensor unit (140c) can acquire vehicle status and surrounding environment information. The autonomous driving unit (140d) can update the autonomous driving route and driving plan based on newly acquired data / information. The communication unit (110) can transmit information regarding the vehicle location, autonomous driving route, driving plan, etc. to the external server. External servers can predict traffic information data in advance using AI technology or other technologies based on information collected from vehicles or autonomous vehicles, and provide the predicted traffic information data to the vehicles or autonomous vehicles.

[0409] The embodiments described above are combinations of components and features of the present invention in a predetermined form. Each component or feature should be considered optional unless explicitly stated otherwise. Each component or feature may be implemented without being combined with other components or features. Furthermore, it is also possible to form an embodiment of the present invention by combining some components and / or features. The order of 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 self-evident that claims that do not have an explicit citation relationship in the patent claims may be combined to form an embodiment or may be incorporated as a new claim through a post-application amendment.

[0410] It will be apparent to those skilled in the art that the present invention can be embodied in other specific forms without departing from the scope of the invention. Therefore, the above detailed description should not be construed as limiting in any respect, but rather as illustrative. The scope of the present invention should be determined by a reasonable interpretation of the appended claims, and all modifications within the scope of equivalents of the present invention are intended to be included within the scope of the present invention.

[0411] The present invention can be used in a terminal, base station, or other equipment of a wireless mobile communication system.

Claims

1. In a method performed by a terminal, Receive sounding reference signal (SRS) settings via upper layer signaling; Perform SRS resource mapping for multiple SRS antenna ports based on the above SRS settings; and Including transmitting SRS through the plurality of SRS antenna ports based on the SRS resource mapping, Based on the number of the above multiple SRS antenna ports being 3, the terminal: The SRS resource mapping is performed based on the SRS resource mapping method defined for four SRS antenna ports. A method for performing SRS transmission by muting the last SRS port among the four SRS antenna ports.

2. In paragraph 1, A method further comprising receiving downlink control information (DCI) instructing to transmit the SRS through three SRS antenna ports.

3. In paragraph 1, Further comprising transmitting a PUSCH (physical uplink control channel) based on a non-coherent codebook supporting three antenna ports, The above non-coherent codebook includes precoding matrices constructed based on Table A for each rank, [Table A] A method in which the precoding matrices in Table A above are normalized to 1 / √3.

4. In paragraph 1, Further comprising transmitting a PUSCH (physical uplink control channel) based on a non-coherent codebook supporting three antenna ports, The above non-coherent codebook includes precoding matrices constructed based on Table B for each rank, [Table B] Method in which the x, y and z values ​​in Table B above are variables given via network signaling.

5. In paragraph 4, The above network signaling includes a 2-bit index, and the 2-bit index indicates the x, y and z values ​​based on Table C. [Table C] , method.

6. In paragraph 4, One of the three antenna ports for the above PUSCH is set as a reference antenna port, A method wherein the network signaling indicates the x, y and z values ​​based on the reference antenna port.

7. In paragraph 6, A method further comprising receiving information indicating the reference antenna port.

8. In paragraph 6, A method wherein the above reference antenna port is an antenna port linked to an uplink layer indicator included in DCI (downlink control information) that schedules the PUSCH.

9. A non-transitory computer-readable recording medium having recorded thereon a program for performing the method described in paragraph 1.

10. In the device, memory for storing commands; and A processor for performing operations by executing the above instructions, The operations of the above processor are: Receive sounding reference signal (SRS) settings via upper layer signaling; Perform SRS resource mapping for multiple SRS antenna ports based on the above SRS settings; and Including transmitting SRS through the plurality of SRS antenna ports based on the SRS resource mapping, Based on the number of the above multiple SRS antenna ports being 3, the device: The SRS resource mapping is performed based on the SRS resource mapping method defined for four SRS antenna ports. A device that performs the SRS transmission by muting the last SRS port among the four SRS antenna ports.

11. In Article 10, Including a transceiver, The above device is a terminal operating in a wireless communication system.

12. In paragraph 10, The above device is a processing device configured to control a terminal operating in a wireless communication system.

13. In a method performed by a base station, Transmitting sounding reference signal (SRS) settings via upper layer signaling; and Including receiving an SRS transmitted through a plurality of SRS antenna ports based on the above SRS settings, Based on the number of the above multiple SRS antenna ports being 3, the base station receives the SRS based on an SRS resource mapping method defined for 4 SRS antenna ports, A method wherein the last SRS port among the above four SRS antenna ports is muted.

14. A non-transitory computer-readable recording medium having recorded thereon a program for performing the method described in Article 13.

15. At the base station, memory for storing commands; and A processor for performing operations by executing the above instructions, The operations of the above processor are: Transmitting sounding reference signal (SRS) settings via upper layer signaling; and Including receiving an SRS transmitted through a plurality of SRS antenna ports based on the above SRS settings, Based on the number of the above multiple SRS antenna ports being 3, the base station receives the SRS based on an SRS resource mapping method defined for 4 SRS antenna ports, A base station in which the last SRS port among the above four SRS antenna ports is muted.

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