Method performed by terminal or network in wireless communication system and apparatus therefor

Abstract

A method performed by a terminal, according to one embodiment of the present disclosure, may comprise: receiving configuration information for channel state information-reference signal (CSI-RS) resources via higher layer signaling; calculating CSI for coherent joint transmission (CJT) on the basis of the configuration information; and transmitting a CSI report on the basis of the CSI, wherein the calculation of the CSI may include calculating at least one of a time difference, a frequency difference, and a phase difference of each CSI-RS resource with respect to a reference CSI-RS resource from among the CSI-RS resources, and a CSI processing unit (CPU) used in the calculation of the CSI may be determined on the basis of at least one scaling value set for the CJT.

Description

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

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

[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] The current NR standard defines coherent joint transmission (CJT), where multiple TRPs transmit signals together to a single UE. However, it assumes an ideal backhaul with zero delay and perfect synchronization between multiple TRPs, making it difficult for CJT to operate correctly in real-world environments. In practice, non-ideal backhaul is common between TRPs, resulting in frequency / time / phase synchronization errors between different TRPs.

[0004] The technical task of the present disclosure is to provide a method and device for efficiently performing wireless signal transmission and reception processes. As an example, considering non-ideal backhaul conditions between TRPs, we propose rules for terminal CSI processing in CSI reports to compensate for time / frequency / phase misalignment between TRPs for CJT operation.

[0005] In addition to the technical challenges described above, 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 configuration information for channel state information-reference signal (CSI-RS) resources through higher layer signaling; calculating CSI for coherent joint transmission (CJT) based on the configuration information; and transmitting a CSI report based on the CSI, wherein calculating the CSI includes calculating at least one of a time difference, a frequency difference, or a phase difference of each CSI-RS resource with respect to a reference CSI-RS resource among the CSI-RS resources, and a CPU (CSI processing unit) occupied by the calculation of the CSI can be determined based on at least one scaling value set for the CJT.

[0007] The at least one scaling value may be individually set for each of the time difference, the frequency difference and the phase difference.

[0008] Based on the fact that the output of the CSI includes all of the time difference, the frequency difference, and the phase difference, the CPU may be determined based on the sum of a first scaling value set for the time difference, a second scaling value set for the frequency difference, and a third scaling value set for the phase difference.

[0009] The at least one scaling value may be determined based on a capability report of the terminal.

[0010] The above CPU can be determined based on the number of TRPs (transmission reception points) for the CJT.

[0011] The CPU may be determined based on the product of X determined based on the at least one scaling value and N determined based on the number of TRPs.

[0012] The above CSI report may be an aperiodic CSI report triggered via a physical downlink control channel (PDCCH).

[0013] Based on the above CSI being for the above CJT, at least one of a Z value related to the time length from the last symbol of the PDCCH to the first symbol of the CSI report and a Z' value related to the time length from the last symbol of the CSI-RS resource to the first symbol of the CSI report may be shortened.

[0014] 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.

[0015] According to another aspect of the present disclosure, a device comprises: a memory configured to store instructions; and a processor configured to perform operations by executing the instructions, wherein the operations of the processor include receiving configuration information for channel state information-reference signal (CSI-RS) resources through higher layer signaling; calculating CSI for coherent joint transmission (CJT) based on the configuration information; and transmitting a CSI report based on the CSI, wherein calculating the CSI includes calculating at least one of a time difference, a frequency difference, or a phase difference of each CSI-RS resource with respect to a reference CSI-RS resource among the CSI-RS resources, and a CPU (CSI processing unit) occupied by the calculation of the CSI can be determined based on at least one scaling value set for the CJT.

[0016] The above device may further include a transceiver.

[0017] The above device may be a terminal in a wireless communication system.

[0018] The above device may be a processing device configured to control a terminal in a wireless communication system.

[0019] According to another aspect of the present disclosure, a method performed by at least one base station includes transmitting configuration information for channel state information-reference signal (CSI-RS) resources to a terminal through higher layer signaling; and receiving a CSI report including CSI for coherent joint transmission (CJT) from the terminal based on the configuration information, wherein the CSI includes at least one of a time difference, a frequency difference, or a phase difference of each CSI-RS resource with respect to a reference CSI-RS resource among the CSI-RS resources, and a CPU (CSI processing unit) of the terminal occupied by the CSI can be determined based on at least one scaling value set for the CJT.

[0020] 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.

[0021] According to another aspect of the present disclosure, a base station includes a memory configured to store instructions; and a processor configured to perform operations by executing the instructions, wherein the operations of the processor include transmitting configuration information for channel state information-reference signal (CSI-RS) resources to a terminal through higher layer signaling; and receiving a CSI report including CSI for coherent joint transmission (CJT) from the terminal based on the configuration information, wherein the CSI includes at least one of a time difference, a frequency difference, or a phase difference of each CSI-RS resource with respect to a reference CSI-RS resource among the CSI-RS resources, and a CPU (CSI processing unit) of the terminal occupied by the CSI can be determined based on at least one scaling value set for the CJT.

[0022] According to the present disclosure, wireless signal transmission and reception can be efficiently performed in a wireless communication system. For example, CPU occupancy and CSI processing delay values ​​for CJT reporting are defined to adjust for time / frequency / phase misalignment between TRPs considering non-ideal backhaul conditions, thereby enabling more accurate CSI reporting between terminals and base stations.

[0023] In addition to the technical effects described above, other technical effects can be inferred from the description below.

[0024] 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.

[0025] Figure 2 illustrates the structure of a radio frame.

[0026] Figure 3 illustrates a resource grid of slots.

[0027] Figure 4 illustrates an example of physical channels being mapped within a slot.

[0028] Figure 5 illustrates the PDSCH and ACK / NACK transmission process.

[0029] Figure 6 illustrates a PUSCH transmission process.

[0030] Figure 7 shows an example of a CSI-related procedure.

[0031] Figure 8 illustrates multiple TRP transmissions.

[0032] FIG. 9 illustrates a flow of a method performed by a terminal according to one embodiment.

[0033] FIG. 10 illustrates a flow of a method performed by a base station according to one embodiment.

[0034] Figures 11 to 14 illustrate communication systems and wireless devices applicable to the present disclosure.

[0035] 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.

[0036] As more and more communication devices demand greater communication capacity, the need for improved mobile broadband communications compared to existing Radio Access Technology (RAT) is emerging. Furthermore, massive Machine Type Communications (MTC), 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.

[0037] For clarity of explanation, the description will focus on 3GPP NR, but the technical idea of ​​the present invention is not limited thereto.

[0038] 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.

[0039] 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.

[0040] Figure 1 is a drawing for explaining physical channels used in a 3GPP NR system and a general signal transmission method using them.

[0041] 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.

[0042] 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.

[0043] 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.

[0044] 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.

[0045] 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.

[0046] 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.

[0047] 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

[0048] * N slot symb : Number of symbols in the slot

[0049] * N frame,u slot : Number of slots in the frame

[0050] * N subframe,u slot : Number of slots in a subframe

[0051] 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.

[0052] SCS (15*2^u)N slot symb N frame,u slot N subframe,u slot 60KHz (u=2)12404

[0053] 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.

[0054] 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).

[0055] 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.

[0056] 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.

[0057] Below, each physical channel is described in more detail.

[0058] 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).

[0059] 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.

[0060] 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.

[0061] - controlResourceSetId: Indicates the CORESET associated with the search space.

[0062] - monitoringSlotPeriodicityAndOffset: Indicates the PDCCH monitoring period (in slots) and the PDCCH monitoring interval offset (in slots).

[0063] - monitoringSymbolsWithinSlot: Indicates the PDCCH monitoring symbols within the slot (e.g., the first symbol(s) of the CORESET).

[0064] - nrofCandidates: AL={1, 2, 4, 8, 16} indicates the number of PDCCH candidates (one of 0, 1, 2, 3, 4, 5, 6, 8)

[0065] * 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.

[0066] Table 3 illustrates the characteristics of each search space type.

[0067] 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

[0068] Table 4 illustrates DCI formats transmitted via PDCCH.

[0069] 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

[0070] 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.

[0071] 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.

[0072] 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.

[0073] PUCCH carries Uplink Control Information (UCI). UCI includes:

[0074] - SR (Scheduling Request): Information used to request UL-SCH resources.

[0075] - 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.

[0076] - 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).

[0077] 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).

[0078] 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)

[0079] 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.

[0080] 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)).

[0081] 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.

[0082] 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.

[0083] 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.

[0084] 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.

[0085] 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.

[0086] 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:

[0087] - Frequency domain resource assignment: Indicates the set of RBs allocated to the PDSCH.

[0088] - 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).

[0089] - PDSCH-to-HARQ_feedback timing indicator: Indicates K1

[0090] - HARQ process number (4 bits): Indicates the HARQ process ID (Identity) for data (e.g., PDSCH, TB)

[0091] - PUCCH resource indicator (PRI): Indicates the PUCCH resource to be used for UCI transmission among multiple PUCCH resources within the PUCCH resource set.

[0092] 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.

[0093] 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.

[0094] 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.

[0095] 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.

[0096] 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.

[0097] 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.

[0098] 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 success or failure of the 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.

[0099] 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.

[0100] - Frequency domain resource assignment: Indicates the set of RBs allocated to PUSCH.

[0101] - 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.

[0102] 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.

[0103] CSI-related actions

[0104] Figure 7 shows an example of a CSI-related procedure.

[0105] 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.

[0106] - 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.

[0107] - 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.

[0108] - 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.

[0109] - 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.

[0110] - 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.

[0111] 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).

[0112] 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.

[0113] 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.

[0114] Table 6 is an excerpt from the TS 38.214 standard document regarding CSI processing criteria.

[0115]

[0116]

[0117]

[0118]

[0119]

[0120]

[0121]

[0122] Table 7 is an excerpt from TS38.214 regarding the terminal's CSI computation time.

[0123]

[0124]

[0125]

[0126]

[0127]

[0128] QCL (quasi-co location)

[0129] 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.

[0130] 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:

[0131] - 'QCL-TypeA': {Doppler shift, Doppler spread, average delay, delay spread}

[0132] - 'QCL-TypeB': {Doppler shift, Doppler spread}

[0133] - 'QCL-TypeC': {Doppler shift, average delay}

[0134] - 'QCL-TypeD': {Spatial Rx parameter}

[0135] M-TRP (multiple-transmission / reception point) related operations

[0136] 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. For example, 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 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.

[0137] 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.

[0138] 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.).

[0139] Techniques are discussed for multi-TRP based URLLC scheduled by a single DCI, as shown in Table 8 below.

[0140] 1) Technique 1 (SDM): Time and frequency resource allocation overlap, n (n<=Ns) TCI states in a single slot1-a) Technique 1a- At each transmission occasion, the same TB is transmitted in one layer or set of layers, and each layer or set of layers is associated with one TCI and one set of DMRS port(s).- A single codeword with one RV is used in all spatial layers or sets of all layers. From the UE perspective, different coded bits are mapped to different layers or sets of layers using the same mapping rule.1-b) Technique 1b- At each transmission occasion, the same TB is transmitted in one layer or set of layers, and each layer or set of layers is associated with one TCI and one set of DMRS port(s).- A single codeword with one RV is used in each spatial layer or set of layers. The RV(s) corresponding to each spatial layer or each set of layers may be the same or different. 1-c) Technique 1c- At one transmission occasion, the same TB having one DMRS port associated with multiple TCI state indices is transmitted in one layer, or the same TB having multiple DMRS ports that are one-to-one associated with multiple TCI state indices is transmitted in one layer. In the above-mentioned techniques 1a and 1c, the same MCS is applied to all layers or all sets of layers. 2) Technique 2 (FDM): Frequency resource allocations are non-overlapping, n (n<=Nf) TCI states in a single slot - Each non-overlapping frequency resource allocation is associated with one TCI state - The same single / multiple DMRS port(s) are associated with all non-overlapping frequency resource allocations.2-a) Technique 2a - A single codeword with a single RV is used for all resource allocations. From the UE perspective, common RB matching (mapping of codewords to layers) is applied to all resource allocations. 2-b) Technique 2b - A single codeword with a single RV is used for each non-overlapping frequency resource allocation. The RV corresponding to each non-overlapping frequency resource allocation can be the same or different. For the above scheme 2a, the same MCS is applied to all non-overlapping frequency resource allocations. 3) Scheme 3 (TDM): Time resource allocations are non-overlapping, and n (n<=Nt1) TCI states in a single slot - Each transmission occasion of a TB has one TCI and one RV with a time granularity of a mini-slot. - A common MCS is used for all transmission occasions in a slot to a single or multiple DMRS port(s). - The RV / TCI in different transmission occasions can be the same or different. 4) Scheme 4 (TDM): n (n<=Nt2) TCI states in K (n<=K) different slots - Each transmission occasion of a TB has one TCI and one RV. - All transmission occasions across K slots have a single or Uses a common MCS with multiple DMRS port(s). - RV / TCI can be same or different at different transmission occasions.

[0141] Meanwhile, the DL M-TRP URLLC transmission method refers to a method in which multiple TRPs transmit the same data / DCI using different space (e.g., layer / port) / time / frequency resources. For example, TRP 1 can transmit specific data / DCI in resource 1, and TRP 2 can transmit the specific data / DCI (the same data / DCI) in resource 2.

[0142] For example, when the DL M-TRP URLLC transmission method is configured, the terminal can receive the same data / DCI using different space / time / frequency resources. At this time, the terminal can receive an indication from the base station regarding the QCL RS / type (DL TCI state) used in the space / time / frequency resources where the data / DCI is received.

[0143] For example, if the corresponding data / DCI is received from resource 1 and resource 2, the terminal can be instructed by the base station about the DL TCI state used in resource 1 and the DL TCI state used in resource 2. By receiving the corresponding data / DCI through resource 1 and resource 2, high reliability can be achieved. This M-TRP URLLC transmission method can be applied to PDSCH / PDCCH.

[0144] UL M-TRP URLLC transmission method refers to a method in which multiple TRPs receive the same data / UCI from a terminal using different space / time / frequency resources. For example, TRP 1 can receive the same data / UCI from a terminal on resource 1, and TRP 2 can receive the same data / UCI from a terminal on resource 2. In addition, TRP 1 and TRP 2 can share the data / UCI received from the terminal through a backhaul link (connected between TRPs).

[0145] For example, when the UL M-TRP URLLC transmission method is set, the terminal can transmit the same data / UCI to each TRP using different space / time / frequency resources. At this time, the terminal can be instructed by the base station about the Tx beam and Tx power (UL TCI state) to be used in the space / time / frequency resources for transmitting the same data / UCI. For example, when the same data / UCI is transmitted in resource 1 and resource 2, the terminal can be instructed by the base station about the UL TCI state used in resource 1 and the UL TCI state used in resource 2. This UL M-TRP URLLC can be applied to PUSCH / PUCCH.

[0146] In addition, in describing the present disclosure, when receiving / transmitting data / DCI / UCI through specific space / time / frequency resources, using (or mapping) a specific TCI state (or TCI) may mean, in the case of DL, estimating a channel from a DMRS using a QCL type and QCL RS indicated by the specific TCI state in the specific space / time / frequency resources, and receiving / demodulating data / DCI / UCI with the estimated channel.

[0147] And, when receiving / transmitting data / DCI / UCI through specific space / time / frequency resources, using (or mapping) a specific TCI state (or TCI) may mean, in the case of UL, transmitting / modulating DMRS and data / UCI using a Tx beam and / or Tx power indicated by a specific TCI state in a specific space / time / frequency resource.

[0148] In addition, the UL TCI state may include Tx beam or Tx power information of the terminal. In addition, the base station may set other parameters, such as spatial relation information, to the terminal instead of the TCI state.

[0149] For example, the UL TCI state can be directly indicated to the UE via the UL grant DCI. Alternatively, the UL TCI state can mean spatial relationship information of SRS resources indicated via the SRI (SRS resource indicator) field of the UL grant DCI. Alternatively, the UL TCI state can mean an open loop (OP) Tx power control parameter linked to a value indicated via the SRI field of the UL grant DCI.

[0150] Here, the OL Tx power control parameters may include, for example, j (index for OP parameter(s) Po and alpha (set of up to 32 parameter values ​​per cell), q_d (index of DL RS resources for path loss (PL) measurement (up to 4 measurements per cell), or / and I (closed-loop power control process index (up to 2 processes per cell)).

[0151] The M-TRP eMBB transmission method refers to a method in which M-TRP transmits different data / DCI using different space / time / frequency resources. When the M-TRP eMBB transmission method is configured, the terminal can receive multiple TCI states from the base station through DCI, and can assume that the data received using the QCL RS indicated by each of the multiple TCI states are different data.

[0152] In addition, since the RNTI for M-TRP URLLC and the M-TRP eMBB RNTI are used separately, the terminal can determine whether a specific transmission / reception is an M-TRP URLLC transmission / reception or an M-TRP eMBB transmission / reception. For example, if the RNTI for URLLC is used and CRC masking is performed on the DCI, the terminal can determine the corresponding transmission as a URLLC transmission. In addition, if the RNTI for eMBB is used and CRC masking is performed on the DCI, the terminal can determine the corresponding transmission as an eMBB transmission. As another example, the base station can set the M-TRP URLLC transmission / reception method or the M-TRP eMBB transmission / reception method to the terminal through new signaling.

[0153] For the convenience of explaining the present disclosure, it is assumed that two TRPs cooperate with each other to perform transmission / reception operations, but this is not limited thereto. For example, the present disclosure can be expanded to a multi-TRP environment of three or more, and can also be expanded to an environment in which transmission / reception is performed using different panels or beams in the same TRP. A terminal can recognize different TRPs as having different TCI states. When a terminal transmits / receives data / DCI / UCI using TCI state 1, this means that it transmits / receives data / DCI / UCI / from TRP 1 (or to TRP 1).

[0154] The present disclosure can be utilized in situations where M-TRPs perform cooperative transmission of PDCCHs (repeatedly transmitting or splitting the same PDCCH). Furthermore, the present disclosure can also be utilized in situations where M-TRPs perform cooperative transmission of PDSCHs or cooperatively receive PUSCHs / PUCCHs.

[0155] Additionally, the fact that multiple base stations (M-TRP) repeatedly transmit the same PDCCH may mean that the same DCI is transmitted through multiple PDCCH candidates, which is the same as the fact that multiple base stations repeatedly transmit the same DCI. Here, two DCIs with the same DCI format / size / payload can be viewed as the same DCI.

[0156] Alternatively, if the scheduling results are the same even though the payloads of two DCIs are different, the two DCIs can be considered the same DCI. For example, the time domain resource allocation (TDRA) field of a DCI can relatively determine the slot / symbol positions of data and the slot / symbol positions of A(ACK) / N(NACK) based on the time of reception of the DCI.

[0157] At this time, if the DCI received at point n and the DCI received at point n+1 indicate the same scheduling result to the terminal, the TDRA fields of the two DCIs will be different, and as a result, the DCI payloads will be different. Therefore, even if the payloads of the two DCIs are different, if the scheduling results are the same, the two DCIs can be viewed as the same DCI. Here, the number of repetitions R can be directly indicated by the base station to the terminal or can be mutually agreed upon.

[0158] Alternatively, even if the payloads of two DCIs are different and the scheduling results are not identical, if the scheduling result of one DCI is a subset of the scheduling result of the other DCI, the two DCIs can be considered the same DCI.

[0159] For example, if the same data is TDM-transmitted repeatedly N times, DCI 1 received before the first data indicates (or schedules) data repetition N times, and DCI 2 received before the second data indicates data repetition (scheduling) N-1 times. At this time, the scheduling result (or data) of DCI 2 becomes a subset of the scheduling result (or data) of DCI 1, and both DCIs have scheduling results for the same data. Therefore, in this case as well, the two DCIs can be viewed as the same DCI.

[0160] And, multiple base stations (M-TRPs) dividing and transmitting the same PDCCH may mean that one DCI is transmitted through one PDCCH candidate, but TRP 1 transmits some of the resources defined for the PDCCH candidate, and TRP 2 transmits the remaining resources.

[0161] For example, if TRP 1 and TRP 2 divide and transmit PDCCH candidates corresponding to AL (aggregation level) m1 + m2, the PDCCH candidates may be divided into PDCCH candidate 1 corresponding to AL m1 and PDCCH candidate 2 corresponding to AL m2, and TRP 1 may transmit PDCCH candidate 1 and TRP 2 may transmit PDCCH candidate 2. At this time, TRP 1 and TRP 2 may transmit PDCCH candidate 1 and PDCCH candidate 2 using different time / frequency resources. After receiving PDCCH candidate 1 and PDCCH candidate 2, the terminal may generate a PDCCH candidate corresponding to AL m1+m2 and attempt DCI decoding.

[0162] At this time, the method of dividing the same DCI and transmitting it to multiple PDCCH candidates can be implemented in the following two ways.

[0163] The first method is a method in which the DCI payload (e.g., control information + CRC) is encoded through a single channel encoder (e.g., a polar encoder) and transmitted across two TRPs. For example, the first method means a method in which the coded bits obtained based on the encoding result are transmitted across two TRPs. Here, the coded bits transmitted by each TRP may encode the entire DCI payload, but this is not limited to the case, and only a portion of the DCI payload may be encoded.

[0164] The second method divides the DCI payload (e.g., control information + CRC) into two DCIs (e.g., DCI 1 and DCI 2), and then encodes each of them using a channel encoder (e.g., a polar encoder). Then, each of the two TRPs can transmit the coded bits corresponding to DCI 1 and the coded bits corresponding to DCI 2 to the terminal.

[0165] For example, the meaning that multiple base stations (M-TRP) divide / repeat the same PDCCH and transmit it over multiple MOs (monitoring occasions) may mean 1) repeatedly transmitting coded bits encoding the entire DCI content of the corresponding PDCCH through each MO for each base station (S-TRP), 2) dividing the coded bits encoding the entire DCI content of the corresponding PDCCH into multiple parts, and transmitting different parts through each MO for each base station (S-TRP), or 3) dividing the DCI content of the corresponding PDCCH into multiple parts, encoding different parts for each base station (S-TRP) (separate encoding), and transmitting them through each MO.

[0166] Repeated / divided transmission of PDCCH can be understood as transmitting PDCCH multiple times over multiple TOs (transmission occasions).

[0167] In general, a TO (Transmission Occasion) refers to each channel transmitted at a different time when multiple channels are TDMed, each channel transmitted on a different frequency / RB when multiple channels are FDMed, and each channel transmitted on a different layer / beam / DMRS port when multiple channels are SDMed. Each TO can be mapped to one TCI state. When the same channel is repeatedly transmitted, complete data / DCI / UCI is transmitted on one TO, and the receiver can receive multiple TOs to increase the reception success rate.

[0168] For PDCCH transmission, TO may refer to a specific time and / or frequency resource unit in which the PDCCH is transmitted. For example, if the PDCCH is transmitted multiple times (in a specific RB) across slots 1, 2, 3, and 4, TO may refer to each slot. As another example, if the PDCCH is transmitted multiple times (in a specific slot) across RB sets 1, 2, 3, and 4, TO may refer to each RB set. As another example, if the PDCCH is transmitted multiple times across different times and frequencies, TO may refer to each time / frequency resource. In addition, the TCI state used for DMRS channel estimation may be set differently for each TO, and TOs with different TCI states may be assumed to have been transmitted by different TRPs / panels.

[0169] Repeated or divided transmission of a PDCCH by multiple base stations 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.

[0170] In describing the present disclosure, when a terminal repeatedly transmits the same PUSCH to multiple base stations (M-TRP), it may mean that the terminal transmits the same data through multiple PUSCHs, and each PUSCH may be transmitted in an optimized manner on an UL channel of a different TRP.

[0171] For example, a terminal may repeatedly transmit the same data through PUSCH 1 and PUSCH 2. At this time, PUSCH 1 is transmitted using UL TCI state 1 for TRP 1, and link adaptation such as precoder / MCS may also be scheduled with a value optimized for the channel of TRP 1, and the PUSCH may be transmitted. PUSCH 2 is transmitted using UL TCI state 2 for TRP 2, and link adaptation such as precoder / MCS may also be scheduled with a value optimized for the channel of TRP 2, and the PUSCH may be transmitted. At this time, PUSCH 1 and PUSCH 2 that are repeatedly transmitted may be transmitted at different times and may be TDM, FDM, or SDM.

[0172] Additionally, the fact that the terminal divides the same PUSCH and transmits it to multiple base stations (M-TRP) may mean that one data is transmitted through one PUSCH, but the resources allocated to the PUSCH are divided and transmitted in an optimized manner on the UL channels of different TRPs.

[0173] For example, a terminal can transmit the same data through a 10-symbol PUSCH. At this time, the first 5 symbols of the 10 symbols can be transmitted using UL TCI state 1 for TRP 1, and the terminal can transmit the 5-symbol PUSCH (as TRP 1) by scheduling a value optimized for the channel of TRP 1, such as a precoder / MCS, for link adaptation. The remaining 5 symbols can be transmitted using UL TCI state 2 for TRP 2, and the terminal can transmit the remaining 5-symbol PUSCH (as TRP 2) by scheduling a value optimized for the channel of TRP 2, such as a precoder / MCS, for link adaptation.

[0174] In the above example, a method of dividing one PUSCH into time resources and performing TDM for transmission toward TRP 1 and transmission toward TRP 2 was described, but the present disclosure is not limited thereto, and a terminal can divide the same PUSCH and transmit it to multiple base stations by using the FDM / SDM method.

[0175] A terminal can repeatedly transmit a PUCCH to multiple base stations (similar to PUSCH transmission) or divide and transmit the same PUCCH.

[0176] And, when multiple TOs are indicated to a UE in order to repeatedly transmit or divide PDCCH / PDSCH / PUSCH / PUCCH, each TO can transmit UL toward a specific TRP or receive DL from a specific TRP. At this time, the UL TO transmitted toward TRP 1 (or TO of TRP 1) may mean a TO that uses the first value among two spatial relations, two UL TCIs, two UL power control parameters, or two PL (pathloss)-RSs indicated to the UE. And, the UL TO transmitted toward TRP 2 (or TO of TRP 2) means a TO that uses the second value among two spatial relations, two UL TCIs, two UL power control parameters, and two PL-RSs indicated to the UE.

[0177] Similarly, in DL transmission, the DL TO transmitted by TRP 1 (or TO of TRP 1) may mean a TO that uses the first value among the two DL TCI states indicated to the terminal (for example, when two TCI states are set in CORESET), and the DL TO transmitted by TRP 2 (or TO of TRP 2) may mean a TO that uses the second value among the two DL TCI states indicated to the terminal (for example, when two TCI states are set in CORESET).

[0178] The present disclosure can be extended to various channels, such as PUSCH / PUCCH / PDSCH / PDCCH. Furthermore, the present disclosure can be extended to both cases where the channels are repeatedly transmitted on different space / time / frequency resources and cases where the channels are transmitted in segmented manner.

[0179] <MTRP Coherent joint transmission (CJT) 관련 설명>

[0180] Similar to MTRP SFN (single frequency network), MTRP CJT transmits the same data on the same layer and DMRS port in the same time / frequency domain. However, unlike MTRP SFN, MTRP CJT aligns the channel phases of each TRP with each other. Ideally, the two channels are constructively summed to create a composite channel, resulting in higher SNR gain through beamforming than SFN. To ensure that the channel phases of each TRP are aligned with each other, the UE can add the phase difference between the two TRP channels to the existing CSI and provide feedback. Furthermore, when data is transmitted in multiple layers, some layers transmit CJT while others transmit only one TRP. For example, during rank 2 PDSCH transmission, the first layer may perform CJT on TRPs 1 and 2, transmitting the same data on both TRPs, while the second layer may transmit only TRP 1.

[0181] For CSI feedback for CJT transmission (e.g., CSI including co-phase for DL ​​channel of each TRP), the base station can set the CMR (channel measurement resource) and CSI contents in the following manner to enable the UE to measure the channels of the two TRPs.

[0182] 1) Alt 1. One concatenated channel from One CMR

[0183] In the first method, one CSI-RS is set as a CMR, but some ports of the CSI-RS can be transmitted by TRP 1, and the remaining ports can be transmitted by TRP 2. In this method, some ports of the CSI-RS are set with QCL beam information for TRP 1 (or TCI state or QCL reference RS defined in the TCI state), and the remaining ports are set with QCL beam information for TRP 2 (or TCI state or QCL reference RS defined in the TCI state). The UE measures the channel with the corresponding CMR to estimate the channel for as many Tx antenna ports as (the number of ports of TRP 1 + the number of ports of TRP 2) and calculates the PMI for the (the number of ports of TRP 1 + the number of ports of TRP 2) ports. The PMI calculated in this way reflects the optimal co-phase between the ports of TRP 1 and the ports of TRP 1, and feeds back the calculated RI / PMI / CQI to the base station.

[0184] 2) Alt 2. one concatenated channel from two CMR

[0185] In the second method, two CMRs are set, CMR 1 sets CSI-RS 1 transmitted by TRP 1, and CMR 2 sets CSI-RS 2 transmitted by TRP 2. The UE can measure the channel with the corresponding CMR to estimate the channel of TRP 1 and the channel of TRP 2 respectively, and concatenate the estimated channels to create the entire channel of TRP 1 and 2. For example, a 2pt channel of TRP 1 is estimated with CMR 1, a 2pt channel of TRP 2 is estimated with CMR 2, and these are concatenated to create a 4pt channel. RI / PMI / CQI are calculated for the channels created in this way and fed back to the base station.

[0186] 3) Alt 3. two channels from two CMR

[0187] The third method sets two CMRs in the same way as the second method. However, unlike the second method, the UE does not concatenate the channels measured by the corresponding CMRs. It calculates RI1 / PMI1 from the channel of CMR 1, RI2 / PMI2 from the channel of CMR 2, and calculates the co-phase value between each channel. Then, it applies RI1 / PMI1 / RI2 / PMI2 / co-phase / co-amplitude to calculate the CQI that can be achieved when transmitting the CJT PDSCH and feeds it all back.

[0188] CPU occupation for CJT CSI

[0189] Hereinafter, 'beam' can mean a source RS for a 'spatial filter' or a 'spatial relation', and can be interpreted as a QCL (type-D) RS or a (DL / UL / joint) TCI state or a spatial relation RS (in case of uplink).

[0190] Currently, CSI feedback in NR supports a beam / CSI report method in which the UE reports the quality value (e.g., L1-RSRP / SINR) and the corresponding RS ID (e.g., CRI) based on the reference signal to be measured (e.g., SSB or CSI-RS) set by the base station. As described above, in coherent joint transmission (CJT) based on multiple TRPs, M-TRPs transmit the same data together in the same time / frequency domain through the same layer and DM-RS port. This CJT operation of the existing NR standard assumes an ideal synchronization / backhaul state between multiple TRPs. For example, the reference DL timing and channel phase from each TRP are aligned with respect to the target UE, so that a constructive composite channel of multiple channels is formed, which can improve performance in terms of reception quality.

[0191] However, in real-world environments, non-ideal backhaul between TRPs is common, which can lead to problems in synchronization between TRPs.

[0192] The Rel-19 standardization will discuss a series of processes by which terminals measure / report timing misalignment information and / or frequency / phase offset information to compensate for timing, frequency, and / or phase misalignment caused by non-ideal backhaul between TRPs for CJT.

[0193] Specifically, improvements to UE reporting in non-ideal synchronization and backhaul will be discussed, targeting both FDD and TDD in FR1. Assuming a conventional CSI-RS structure, time misalignment and frequency / phase offsets between TRPs can be measured and reported using aperiodic reporting on the PUSCH.

[0194] Terminal reporting for CJT thus takes into account the following:

[0195] - Report content: Information related to time misalignment (between inter-TRPs), information related to frequency / phase offset

[0196] - RS configuration: Reuse of existing CSI-RS design

[0197] - Report container: Stand-alone aperiodic reporting on PUSCH

[0198] In other words, when a terminal provides feedback (named a CJT report) of misalignment correction information for CJT operation to a base station, the report contents can be included and transmitted as AP reporting on PUSCH as a form of existing CSI feedback.

[0199] In this way, a UE report (CJT report) can be transmitted to correct misalignment of time / frequency / phase of inter-TRP due to non-ideal backhaul, but issues such as those in Table 9 need to be considered for the report content.

[0200] Propagation delays between different TRPs and terminals can be different - in addition to these propagation delay differences, DL timing differences between TRPs are added - this combination leads to large delay differences in a frequency selective composite channel. Transmission with Frequency Differences Even assuming the same nominal transmit frequency across multiple TRPs, in practice there will be transmit frequency differences between multiple TRPs due to local oscillator stability. The maximum transmit frequency error of a base station is defined in TS38.104, with the most stringent value being + / -0.5 ppm. Even in this case, there may be a residual frequency error. This frequency error means that the relative phase of the signals received from different TRPs will change over time. For example, at a 1 GHz carrier frequency, the relative phase difference can change by 180 degrees in a 5 ms period. Therefore, the time between measuring the CSI and applying the CSI must be much shorter than 5 ms (which is not realistic in most cases), and the resulting time and phase misalignment may degrade the performance to the point where the expected gain of the CJT cannot be achieved. Regarding the effect of non-ideal channel reciprocity, it is not practical to introduce a connection or coupling circuit between TRPs for inter-TRP antenna coordination.

[0201] Table 10 summarizes the Rel-18 CJT CSI standardization, including information such as the number of cooperating TRPs involved in CSI codebook refinement for CJT MTRP and / or the associated NZP CSI-RS setup.

[0202] Type-II codebook improvement for CJT MTRP, supporting up to 4 TRPs - RI={1,2,3,4} - Number of cooperative TRPs for CJT, N TRP={1,2,3,4} resource configuration NZP CSI-RS (CMR) configuration - CMR contains K>1 NZP CSI-RS resources, where one resource corresponds to one TRP / TRP group (i.e. K=N TRP ) Each CSI-RS resource has the same number of CSI-RS ports. - The associated resource configuration includes a CMR containing N>=1 NZP CSI-RS resources in one CSI-RS resource set. Periodic / semi-persistent / aperiodic NZP CSI-RS are supported. The supported CSI-RS resource parameter configuration follows the existing standards. The UE reports a CSI report only after receiving at least one CSI-RS transmission opportunity for each CSI-RS resource in the CSI-RS resource set that is configured no later than the CSI reference resource, otherwise it drops the report. TRP selection scheme (N is the number of cooperative TRPs assumed in PMI reporting) - N TRP The selection of N among the CSI-RS resources is N of CSI Part 1. TRP It is reported through bit bitmap. CSI calculation and measurement - set N including CMR TRP For CSI-RS resources, the constraints specified for the existing NCJT CSI apply. For example, the set N TRP CSI-RS resources are located in the same slot or two consecutive slots. The required number of CPUs and the Z / Z' value - O_CPU = X*N TRP , where X={1, 1.5, 2} is N TRP is a common parameter, X is reported by the UE according to the UE capability - Z / Z' if N TRP If =1, the existing Z / Z' is used, otherwise, depending on the terminal capability, the existing Z / Z' or the existing Z / Z' + r is used. - When calculating active resources, the existing definition and calculation method are reused.

[0203] When CJT operation is performed considering non-ideal backhaul situation as above, it is necessary to introduce UE report (CJT report) to correct misalignment of time / frequency / phase of inter-TRP, and this can be regarded as CSI. In this case, the CJT report is N TRP (eg N TRP =4) For CJT operation of TRPs, the terminal must calculate the time / frequency / phase difference for NZP CSI-RSs corresponding to other TRPs based on a specific reference CMR (NZP CSI-RS) of the inter-TRP.

[0204] For example, the number of CPU occupations is N TRP may be determined based on (e.g., proportional) and / or may be determined based on (e.g., proportional) a specific parameter (e.g., X) (i.e., O CPU = X*N TRP ).

[0205] Below, we propose a method for setting CPU occupation for CJT report output that corrects misalignment of T / F / P (time / frequency / phase) of the inter-TRP and a method for setting related CSI calculation latency Z / Z'.

[0206] Proposal 1

[0207] Number of CPU occupations for UE report (CJT report) that compensates for inter-TRP misalignment for CJT operation O CPU Suggest a method for making decisions.

[0208] For example, O CPU can be determined based on the scaling value X and the number of TPRs N for CJT. Specifically, O CPU= (Scaling factor, X) * (Number of TRPs during CJT operation, N) can be defined as follows. In the following description, the number of TRPs may be replaced with the number of CMRs.

[0209] The scaling factor X setting may follow at least one of the following, but is not limited to:

[0210] (1) Alt 1: Scaling factor X can be set to a specific value(s) (including X=1) regardless of how the report contents for the corresponding CJT report are structured, and this can be reported as a UE capability.

[0211] (2) Alt 2: Scaling factor X can be set differently depending on the composition method of the report contents for the corresponding CJT report.

[0212] For example, when calculating Time / Frequency / Phase (T / F / P) difference, a separate CPU is configured for each, and the scaling factor values ​​X1, X2, and X3 for each T / F / P can be the same / different.

[0213] -X1 for time difference calculation

[0214] -X2 for frequency difference calculation

[0215] -X3 for phase difference calculation

[0216] For example, if all T / F / P differences are included, the final scaling factor value X can be determined based on X1, X2, and X3. Specifically, X=X1+X2+X3, which is O CPU Can be applied when calculating.

[0217] As another example, if only T and F differences are included, the final scaling factor value X can be determined based on X1 and X2. Specifically, X=X1+X2 and this is O CPU Can be applied when calculating.

[0218] The X1, X2, and X3 values ​​can be determined based on UE capability reporting. For example, the terminal can report each of the X1, X2, and X3 values ​​as UE capability.

[0219] Meanwhile, the number of TRPs N during CJT operation is N TRP or follow N=N TRP It can also be set to -1. For example, if a specific TRP (or CMR) is set as a reference, the number of TRPs (or CMRs) excluding the reference can be considered. This means that the terminal is N TRP If you set a specific RS as a reference for the CMRs of the terminal, the remaining N TRP -Because we calculate the difference for 1 RS.

[0220] Proposal 1 is to perform CPU occupancy O for the terminal to perform measurement of the difference in time / center frequency / phase (T / F / P) of CMR between inter-TRPs for CJT operation and to perform calculations to compose report contents with the corresponding information and / or information required for correction. CPU It means how to decide.

[0221] O CPU N is the maximum number of TRPs participating in the CJT operation. TRP is proportional to, and can be determined by further considering the scaling factor for that value.

[0222] The scaling factor can be a specific fixed value for the corresponding CJT report operation, such as Alt 1.

[0223] Alternatively, as in Alt 2, each CPU can be calculated for each T / F / P content of the CJT report, and the scaling factor values ​​at this time can be the same or different. Therefore, when one or more contents related to T / F / P difference are included as reporting content, each scaling factor can be added up and considered as a scaling factor for the total processing time. The scaling factor(s) can be reported by the terminal to the base station as UE capability information. In addition, N, the total number of TRPs considered for CJT, TRP Based on the T / F / P difference information, the remaining N is based on one specific CMR. TRP - Since it will be expressed as 1 difference, the number of CPUs required for actual operation is N TRP It can be set to be proportional to -1.

[0224] Alternatively, if the amount of computation required to compute the T / F / P difference between CMRs is not considered high, serial processing for this may also be possible. For example, instead of CPU occupation being proportional to the number of CMRs, such as beam / CSI reports, only 1 CPU can be used for the computation for the corresponding CJT report, or the CPU can be used as much as the scaling factor X, but X (e.g., a value determined by UE capability) can be applied as a value independent of the number of CMRs / TRPs.

[0225] As above, when the terminal reports the difference information for T / F / P to the base station by configuring it as UCI, O is provided for each UCI configuration method. CPU Since there may be cases where each of these needs to be applied, the details for this are described.

[0226] Proposal 2

[0227] For example, to support rapid CSI reporting of the CJT report, a value smaller than the previously defined CSI calculation latency (e.g. Z / Z') value can be defined / set.

[0228] As described in Table 7 above, the Z value is related to the time length from the last symbol of the PDCCH that triggers the CSI report to the first symbol of the CSI report. The UE calculates Zref based on the Z value. To satisfy the requirement of a valid CSI report, the time length from the end of the last symbol of the PDCCH that triggers the CSI report to the start of the CP of the first symbol of the CSI report must be at least Zref. Otherwise, the CSI report is not valid, and the UE may not perform the CSI report requested by the corresponding PDCCH.

[0229] The Z' value is related to the time length from the last symbol of the CSI-RS resource to the first symbol of the CSI report. The terminal calculates Z'ref based on the Z' value. To meet the requirement of a valid CSI report, the time length from the end of the last symbol of the CSI-RS resource to the start of the CP of the first symbol of the CSI report must be at least Z'ref. Otherwise, the CSI report is not valid, and the terminal may not perform the CSI report.

[0230] As an improvement to the existing UE CSI computation time, a table with values ​​smaller than Z / Z' of the CSI computation delay requirement 1 / 2 (e.g., table 5.4-1 / 5.4-2 of the existing TS 38.214 as extracted in Table 7) may be added for CJT reporting, or the Z / Z' value of delay requirement 1 may be used for the reporting.

[0231] Proposal 2 not only requires relatively less processing time for configuring the contents of the CJT report compared to the calculation for the existing CSI configuration, but also provides information for correcting misalignment for subsequent CJT CSI calculations, so a table with values ​​smaller than table 5.4-1 / 2 of the existing TS 38.214 can be added and used as Z / Z' for the CJT report. Alternatively, the Z / Z' values ​​for (simple CSI) processing of the existing table 5.4-1 can be used for the CJT report.

[0232] FIG. 9 illustrates a flow of a method performed by a terminal according to one embodiment.

[0233] Referring to FIG. 9, a terminal can receive configuration information for CSI-RS (channel state information-reference signal) resources through upper layer signaling.

[0234] The terminal may calculate CSI for coherent joint transmission (CJT) based on the above configuration information (910). Calculating the CSI may include calculating at least one of a time difference, a frequency difference, or a phase difference between each CSI-RS resource and a reference CSI-RS resource among the CSI-RS resources. The CPU (CSI processing unit) occupied by the calculation of the CSI may be determined based on at least one scaling value set for the CJT.

[0235] The terminal can transmit a CSI report based on the above CSI (915).

[0236] The at least one scaling value may be individually set for each of the time difference, the frequency difference and the phase difference.

[0237] Based on the fact that the output of the CSI includes all of the time difference, the frequency difference, and the phase difference, the CPU may be determined based on the sum of a first scaling value set for the time difference, a second scaling value set for the frequency difference, and a third scaling value set for the phase difference.

[0238] The at least one scaling value may be determined based on a capability report of the terminal.

[0239] The above CPU can be determined based on the number of TRPs (transmission reception points) for the CJT.

[0240] The CPU may be determined based on the product of X determined based on the at least one scaling value and N determined based on the number of TRPs.

[0241] The above CSI report may be an aperiodic CSI report triggered via a physical downlink control channel (PDCCH).

[0242] Based on the above CSI being for the above CJT, at least one of a Z value related to the time length from the last symbol of the PDCCH to the first symbol of the CSI report and a Z' value related to the time length from the last symbol of the CSI-RS resource to the first symbol of the CSI report may be shortened.

[0243] FIG. 10 illustrates a flow of a method performed by a base station according to one embodiment.

[0244] Referring to FIG. 10, a base station can transmit configuration information for CSI-RS (channel state information-reference signal) resources to a terminal through upper layer signaling (1005).

[0245] The base station can receive a CSI report including CSI for coherent joint transmission (CJT) from the terminal based on the above setting information (1010).

[0246] The above CSI may include at least one of a time difference, a frequency difference, or a phase difference of each CSI-RS resource compared to a reference CSI-RS resource among the above CSI-RS resources.

[0247] The CPU (CSI processing unit) of the terminal occupied by the CSI can be determined based on at least one scaling value set for the CJT.

[0248] The at least one scaling value may be individually set for each of the time difference, the frequency difference and the phase difference.

[0249] Based on the fact that the output of the CSI includes all of the time difference, the frequency difference, and the phase difference, the CPU may be determined based on the sum of a first scaling value set for the time difference, a second scaling value set for the frequency difference, and a third scaling value set for the phase difference.

[0250] The at least one scaling value may be determined based on a capability report of the terminal.

[0251] The above CPU can be determined based on the number of TRPs (transmission reception points) for the CJT.

[0252] The CPU may be determined based on the product of X determined based on the at least one scaling value and N determined based on the number of TRPs.

[0253] The above CSI report may be an aperiodic CSI report triggered via a physical downlink control channel (PDCCH).

[0254] Based on the above CSI being for the above CJT, at least one of a Z value related to the time length from the last symbol of the PDCCH to the first symbol of the CSI report and a Z' value related to the time length from the last symbol of the CSI-RS resource to the first symbol of the CSI report may be shortened.

[0255] Fig. 11 illustrates a communication system (1) applicable to the present disclosure.

[0256] Referring to FIG. 11, 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.

[0257] 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).

[0258] 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.

[0259] Figure 12 illustrates a wireless device applicable to the present disclosure.

[0260] Referring to FIG. 12, 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. 11.

[0261] 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.

[0262] 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.

[0263] 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.

[0264] 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.

[0265] 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.

[0266] 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.

[0267] Figure 13 illustrates another example of a wireless device applicable to the present invention. The wireless device may be implemented in various forms depending on the use case / service (see Figure 11).

[0268] Referring to FIG. 13, the wireless device (100, 200) corresponds to the wireless device (100, 200) of FIG. 12 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. 12. For example, the transceiver(s) (114) may include one or more transceivers (106, 206) and / or one or more antennas (108, 208) of FIG. 12. 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).

[0269] 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. 11, 100a), a vehicle (Fig. 11, 100b-1, 100b-2), an XR device (Fig. 11, 100c), a portable device (Fig. 11, 100d), a home appliance (Fig. 11, 100e), an IoT device (Fig. 11, 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. 11, 400), a base station (Fig. 11, 200), a network node, etc. Wireless devices may be mobile or stationary depending on the use / service.

[0270] In FIG. 13, 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 one or more processor sets. 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.

[0271] Figure 14 illustrates a vehicle or autonomous vehicle applicable to the present disclosure. 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, or the like.

[0272] Referring to FIG. 14, 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. 13, respectively.

[0273] 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.

[0274] 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.

[0275] 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 incorporated as a new claim through a post-application amendment.

[0276] 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.

[0277] The present disclosure may 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 configuration information for CSI-RS (channel state information-reference signal) resources through upper layer signaling; Calculate CSI for coherent joint transmission (CJT) based on the above setting information; and Including transmitting a CSI report based on the above CSI, The calculation of the above CSI includes calculating at least one of a time difference, a frequency difference, or a phase difference of each CSI-RS resource compared to a reference CSI-RS resource among the above CSI-RS resources, A method in which the CPU (CSI processing unit) occupied by the output of the above CSI is determined based on at least one scaling value set for the above CJT.

2. In paragraph 1, A method wherein the at least one scaling value is individually set for each of the time difference, the frequency difference and the phase difference.

3. In paragraph 2, A method in which the CPU is determined based on the sum of a first scaling value set for the time difference, a second scaling value set for the frequency difference, and a third scaling value set for the phase difference, based on the fact that the output of the CSI includes all of the time difference, the frequency difference, and the phase difference.

4. In paragraph 1, A method wherein at least one scaling value is determined based on a capability report of the terminal.

5. In paragraph 1, A method in which the CPU is determined based on the number of TRPs (transmission reception points) for the CJT.

6. In paragraph 5, A method wherein the CPU is determined based on the product of X determined based on the at least one scaling value and N determined based on the number of TRPs.

7. In paragraph 1, The above CSI report is an aperiodic CSI report triggered via a physical downlink control channel (PDCCH).

8. In paragraph 7, A method in which at least one of a Z value related to the time length from the last symbol of the PDCCH to the first symbol of the CSI report and a Z' value related to the time length from the last symbol of the CSI-RS resource to the first symbol of the CSI report is shortened based on the above CSI being for the CJT.

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, a memory configured to store instructions; and A processor configured to perform operations by executing the above instructions, The operations of the above processor are: Receive configuration information for CSI-RS (channel state information-reference signal) resources through upper layer signaling; Calculate CSI for coherent joint transmission (CJT) based on the above setting information; and Including transmitting a CSI report based on the above CSI, The calculation of the above CSI includes calculating at least one of a time difference, a frequency difference, or a phase difference of each CSI-RS resource compared to a reference CSI-RS resource among the above CSI-RS resources, A device in which the CPU (CSI processing unit) occupied by the output of the above CSI is determined based on at least one scaling value set for the above CJT.

11. In paragraph 10, Including a transmitter and receiver, The above device is a terminal in a wireless communication system.

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

13. In a method performed by at least one base station, Transmitting configuration information about CSI-RS (channel state information-reference signal) resources to the terminal through upper layer signaling; and Including receiving a CSI report including CSI for coherent joint transmission (CJT) from the terminal based on the above setting information, The above CSI includes at least one of a time difference, a frequency difference, or a phase difference of each CSI-RS resource compared to a reference CSI-RS resource among the above CSI-RS resources, A method in which the CPU (CSI processing unit) of the terminal occupied by the CSI is determined based on at least one scaling value set for the CJT.

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, a memory configured to store instructions; and A processor configured to perform operations by executing the above instructions, The operations of the above processor are: Transmitting configuration information about CSI-RS (channel state information-reference signal) resources to the terminal through upper layer signaling; and Including receiving a CSI report including CSI for coherent joint transmission (CJT) from the terminal based on the above setting information, The above CSI includes at least one of a time difference, a frequency difference, or a phase difference of each CSI-RS resource compared to a reference CSI-RS resource among the above CSI-RS resources, A base station, wherein the CPU (CSI processing unit) of the terminal occupied by the CSI is determined based on at least one scaling value set for the CJT.

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