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

Abstract

A method performed by a terminal, according to at least one from among embodiments disclosed in the present specification, comprises: receiving a CSI-RS configuration through higher layer signaling; receiving a CSI-RS on the basis of the CSI-RS configuration; and acquiring CSI on the basis of the CSI-RS, wherein the CSI-RS is provided through P antenna ports, P is an integer that is greater than 32 but does not exceed 128, the CSI-RS configuration includes a configuration for a plurality of CSI-RS resources related to the P antenna ports, the configuration for the plurality of CSI-RS resources includes information about a slot offset value of each CSI-RS resource, and the plurality of CSI-RS resources can be mapped, on the basis of the slot offset value, within a time interval corresponding to T slots.

Description

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

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

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

[0003] In NR Rel.15-18, up to 32-Tx port CSI-RS transmission is supported, and CSI-RS resources can be mapped to even PRB or odd PRB in the frequency domain to reduce density.

[0004] The technical challenge to be achieved is to provide a method and device for accurately and efficiently performing wireless signal transmission and reception processes. According to one embodiment, a method for transmitting and receiving CSI-RS based on more than 32 ports and a terminal / base station for the same can be provided.

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

[0006] According to one aspect of the present disclosure, a method performed by a terminal includes receiving a CSI-RS (channel state information - reference signal) configuration through higher layer signaling; receiving a CSI-RS based on the CSI-RS configuration; and acquiring CSI based on the CSI-RS, wherein the CSI-RS is provided through P antenna ports, P is an integer greater than 32 and not exceeding 128, the CSI-RS configuration includes configurations for a plurality of CSI-RS resources related to the P antenna ports, the configurations for the plurality of CSI-RS resources include information on a slot offset value of each CSI-RS resource, and the plurality of CSI-RS resources can be mapped within a time interval corresponding to T slots based on the slot offset value.

[0007] The above T slots can be two consecutive slots.

[0008] The above P can be 64 or 128.

[0009] Each CSI-RS resource can be mapped to one of the two slots based on the slot offset value.

[0010] The CSI can be acquired based on the aggregation of CSI-RS resources mapped to the first slot among the two slots and CSI-RS resources mapped to the second slot.

[0011] The above slot offset value can be 0 or 1.

[0012] The density of the CSI-RS, which is determined based on the number P of the antenna ports for the CSI-RS, the number of REs (resource elements) and the number of RBs (resource blocks), may be 0.5.

[0013] Each CSI-RS resource can be mapped to either an even physical resource block (PRB) or an odd PRB in the frequency domain.

[0014] Among the plurality of CSI-RS resources, a first CSI-RS resource may be mapped to an even PRB of a first slot among the T slots, and a second CSI-RS resource may be mapped to an odd PRB of a second slot among the T slots.

[0015] The terminal may not expect the plurality of CSI-RS resources to collide with other signals having a higher priority than the CSI-RS.

[0016] The above CSI-RS may be an aperiodic CSI-RS.

[0017] According to another aspect of the present disclosure, a non-transitory computer-readable recording medium having recorded thereon instructions for performing the method described above may be provided.

[0018] According to another aspect of the present disclosure, a device includes a memory that stores instructions; and a processor that performs operations by executing the instructions, wherein the operations of the processor include receiving a channel state information-reference signal (CSI-RS) configuration through higher layer signaling; receiving a CSI-RS based on the CSI-RS configuration; and acquiring CSI based on the CSI-RS, wherein the CSI-RS is provided through P antenna ports, and P is an integer greater than 32 and not exceeding 128, and the CSI-RS configuration includes a configuration for a plurality of CSI-RS resources related to the P antenna ports, and the configuration for the plurality of CSI-RS resources includes information on a slot offset value of each CSI-RS resource, and the plurality of CSI-RS resources can be mapped within a time interval corresponding to T slots based on the slot offset value.

[0019] The above device may further include a transmitter and receiver.

[0020] The above device may be a terminal operating in a wireless communication system.

[0021] The above device may be a processing device configured to control a terminal operating in a wireless communication system.

[0022] According to another aspect of the present disclosure, a method performed by a base station includes transmitting a CSI-RS (channel state information - reference signal) configuration to a terminal through higher layer signaling; transmitting a CSI-RS to the terminal based on the CSI-RS configuration; and receiving a CSI report from the terminal, wherein the CSI-RS is provided through P antenna ports, P is an integer greater than 32 and not exceeding 128, the CSI-RS configuration includes configurations for a plurality of CSI-RS resources related to the P antenna ports, the configurations for the plurality of CSI-RS resources include information on a slot offset value of each CSI-RS resource, and the plurality of CSI-RS resources can be mapped within a time interval corresponding to T slots based on the slot offset value.

[0023] According to another aspect of the present disclosure, a base station includes a memory that stores commands; and a processor that performs operations by executing the commands, wherein the operations of the processor include transmitting a CSI-RS (channel state information - reference signal) configuration to a terminal through higher layer signaling; transmitting a CSI-RS to the terminal based on the CSI-RS configuration; and receiving a CSI report from the terminal, wherein the CSI-RS is provided through P antenna ports, and P is an integer greater than 32 and not exceeding 128, and the CSI-RS configuration includes a configuration for a plurality of CSI-RS resources related to the P antenna ports, and the configuration for the plurality of CSI-RS resources includes information on a slot offset value of each CSI-RS resource, and the plurality of CSI-RS resources can be mapped within a time interval corresponding to T slots based on the slot offset value.

[0024] According to at least one of the disclosed embodiments, a wireless signal transmission and reception process can be performed accurately and efficiently. According to one embodiment, system throughput can be improved by supporting up to 128 CSI-RS ports, and overhead increase due to an increase in the number of CSI-RS ports can be mitigated by distributing and mapping CSI-RS resources to multiple aggregated slots in the time domain.

[0025] Other effects can be inferred from the description below.

[0026] 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.

[0027] Figure 2 illustrates the structure of a radio frame.

[0028] Figure 3 illustrates a resource grid of slots.

[0029] Figure 4 illustrates an example of physical channels being mapped within a slot.

[0030] Figure 5 illustrates the PDSCH and ACK / NACK transmission process.

[0031] Figure 6 illustrates a PUSCH transmission process.

[0032] Figure 7 shows an example of a CSI-related procedure.

[0033] Figure 8 illustrates multiple TRP transmissions.

[0034] Figure 9 illustrates CSI-RS mapped based on FDM / TDM / CDM in this way.

[0035] FIG. 10 illustrates a CDM-16 pattern according to one embodiment.

[0036] Figures 11 and 12 illustrate examples of CSI-RS mapping for time domain density reduction according to one embodiment.

[0037] FIGS. 13 to 15 illustrate examples of CSI-RS mapping for frequency domain density reduction according to one embodiment.

[0038] FIG. 16 and FIG. 17 are diagrams each illustrating indexing of CSI-RS ports according to one embodiment.

[0039] Figure 18 illustrates an example of a 32 port CSI-RS configuration.

[0040] Figure 19 is an example of a 64 port CSI-RS configuration and port indexing by aggregating two legacy 32 port CSI-RSs.

[0041] Figure 20 is an example of an operation procedure of a base station and a terminal according to one embodiment.

[0042] FIG. 21 illustrates a flow of a method performed by a terminal according to one embodiment.

[0043] FIG. 22 illustrates a flow of a method performed by a base station according to one embodiment.

[0044] Figures 23 to 26 illustrate a communication system (1) and a wireless device applicable to various embodiments.

[0045] 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.

[0046] 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.

[0047] For clarity of explanation, the description will focus on 3GPP NR, but the technical idea of ​​the present invention is not limited thereto.

[0048] 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 upon 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 upon 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.

[0049] 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.

[0050] Figure 1 is a drawing for explaining physical channels used in a 3GPP NR system and a general signal transmission method using them.

[0051] 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.

[0052] 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.

[0053] 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.

[0054] 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.

[0055] 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.

[0056] 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.

[0057] 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

[0058] * N slot symb : Number of symbols in the slot

[0059] * N frame,u slot : Number of slots in the frame

[0060] * N subframe,u slot : Number of slots in a subframe

[0061] 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.

[0062] SCS (15*2^u)N slot symb N frame,u slot N subframe,u slot 60KHz (u=2)12404

[0063] 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.

[0064] 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).

[0065] 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.

[0066] 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.

[0067] Below, each physical channel is described in more detail.

[0068] The PDCCH carries DCI (Downlink Control Information). For example, the PDCCH (DCI) carries the transmission format and resource allocation of the DL-SCH (downlink shared channel), resource allocation information for the UL-SCH (uplink shared channel), paging information for the PCH (paging channel), 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).

[0069] 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.

[0070] 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.

[0071] - controlResourceSetId: Indicates the CORESET associated with the search space.

[0072] - monitoringSlotPeriodicityAndOffset: Indicates the PDCCH monitoring period (in slots) and the PDCCH monitoring interval offset (in slots).

[0073] - monitoringSymbolsWithinSlot: Indicates the PDCCH monitoring symbols within the slot (e.g., the first symbol(s) of the CORESET).

[0074] - nrofCandidates: AL={1, 2, 4, 8, 16} indicates the number of PDCCH candidates (one of 0, 1, 2, 3, 4, 5, 6, 8)

[0075] An opportunity (e.g., time / frequency resource) for monitoring PDCCH candidates is defined as a PDCCH (monitoring) opportunity. One or more PDCCH (monitoring) opportunities may be configured within a slot.

[0076] Table 3 illustrates the characteristics of each search space type.

[0077] 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

[0078] Table 4 illustrates DCI formats transmitted via PDCCH.

[0079] 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

[0080] 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.

[0081] 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.

[0082] 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.

[0083] PUCCH carries Uplink Control Information (UCI). UCI includes:

[0084] - SR (Scheduling Request): Information used to request UL-SCH resources.

[0085] - 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.

[0086] - 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).

[0087] 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).

[0088] 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)

[0089] 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.

[0090] 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)).

[0091] 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.

[0092] 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.

[0093] 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.

[0094] 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.

[0095] 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.

[0096] 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:

[0097] - Frequency domain resource assignment: Indicates the set of RBs allocated to the PDSCH.

[0098] - 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).

[0099] - PDSCH-to-HARQ_feedback timing indicator: Indicates K1

[0100] - HARQ process number (4 bits): Indicates the HARQ process ID (Identity) for data (e.g., PDSCH, TB)

[0101] - PUCCH resource indicator (PRI): Indicates the PUCCH resource to be used for UCI transmission among multiple PUCCH resources within the PUCCH resource set.

[0102] 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.

[0103] 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.

[0104] 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.

[0105] 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.

[0106] 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.

[0107] 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.

[0108] 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.

[0109] 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.

[0110] - Frequency domain resource assignment: Indicates the set of RBs allocated to PUSCH.

[0111] - 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.

[0112] 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.

[0113] CSI-related actions

[0114] Figure 7 shows an example of a CSI-related procedure.

[0115] 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.

[0116] - 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.

[0117] - 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.

[0118] - 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.

[0119] - 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.

[0120] - 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.

[0121] 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).

[0122] 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.

[0123] 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.

[0124] QCL (quasi-co location)

[0125] 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.

[0126] 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:

[0127] - 'QCL-TypeA': {Doppler shift, Doppler spread, average delay, delay spread}

[0128] - 'QCL-TypeB': {Doppler shift, Doppler spread}

[0129] - 'QCL-TypeC': {Doppler shift, average delay}

[0130] - 'QCL-TypeD': {Spatial Rx parameter}

[0131] M-TRP (multiple-transmission / reception point) related operations

[0132] Figure 8 illustrates multi-TRP transmission. Referring to Figure 8(a), groups of layers transmitting the same CW (codeword) (or TB) correspond to different TRPs. Referring to Figure 8(b), different CWs are transmitted through layer groups of different TRPs. At this time, it can be assumed that the TBs corresponding to CW #1 and CW #2 in the figure are identical. CW #1 and CW #2 each mean that the same TB is converted into different CWs through channel coding, etc. by different TRPs. Therefore, it can be viewed as an example of repeated transmission of the same TB. In the case of Figure 8(b), compared to Figure 8(a), it may have the disadvantage of 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.

[0133] 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.

[0134] 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.).

[0135] Design of 64 and 128 CSI-RS ports

[0136] In Rel-19 NR MIMO or later standards, the number of base station Tx / Rx antenna ports is being considered to increase compared to the existing legacy (e.g., 32-port Tx) to improve system throughput of DL / UL and to enable more flexible MIMO operation. To support this, a new 64 / 128-port CSI-RS design is required, and this specification presents methods for achieving this.

[0137] Table 6 shows the CSI-RS mapping method defined in the existing NR standard (TS 38.211, Rel. 17).

[0138]

[0139]

[0140]

[0141]

[0142] As shown in Table 6, NR's CSI-RS is supported based on FDM / TDM / CDM. Figure 9 illustrates a CSI-RS mapped based on FDM / TDM / CDM in this manner.

[0143] Based on the above CSI-RS design, it can be expanded to 64 port / 128 port CSI-RS, and for 64 port / 128 port CSI-RS configuration, the combinations shown in Table 7 below can be considered. Table 7 shows the number of CDM groups required for expansion to 64 / 128 ports.

[0144] 64 port CSI-RS128 port CSI-RSFD CDM-23264FD2-TD2 CDM-41632FD2-TD4 CDM-8816

[0145] Based on the above CDM-2, in order to support 64 port CSI-RS and / or 128 port CSI-RS, the number of configurations that must be set is 32 or 64, which results in a very large signaling overhead. Table 8 below shows examples of FD CDM-2, FD2-TD2 CDM-4, ​​and FD2-TD4 CDM-8 configurations of 64 port CSI-RS.

[0146]

[0147] Additionally, since the transmission power per port may decrease as the number of ports increases in existing CDMs, it is necessary to introduce a larger CDM. To this end, the following is proposed.

[0148] Proposal 1

[0149] To support 64 port / 128 port CSI-RS, CDM-16 configuration can be applied, and FD4-TD4 CDM-16 and / or FD2-TD8 CDM-16 configuration can be supported.

[0150] Figure 10 illustrates the CDM-16 pattern of Proposal 1. Based on this CDM-16, 64 ports require 4 CDM-16 groups, and 128 ports require 8 CDM-16 groups. These CDM groups are aggregated to form 64-port and 128-port CSI-RSs. Tables 9 and 10 below show the CDM sequences of FD4-TD4 CDM-16 and FD2-TD8 CDM-16, respectively.

[0151]

[0152]

[0153] Proposal 2

[0154] In a 64 port / 128 port CSI-RS design, the following time domain / frequency domain density reduction is proposed.

[0155] (1) Option 1. Time domain density reduction

[0156] Figures 11 and 12 illustrate an example of option 1 of proposal 2. Figure 12 shows the case where k is fixed to 1.

[0157] Among multiple CDM-X groups (e.g., X = 2 or 4 or 8 or 16) constituting 64 or 128 port CSI-RS, the first set of Y CDM groups is transmitted in the n-th slot, and the second set of Z CDM groups is transmitted in the n+k-th slot. Here, X*(Y+Z) = P (64 or 128), and when X*Y CSI-RSs transmitted periodically / semi-persistently / aperiodically are transmitted for the nth time, X*Z CSI-RSs are transmitted in the k-th slot (k is RRC configurable, based on the UE capability of the terminal, or can be fixed to a specific value, e.g., k=1). As a special case of the above example, when the number of ports of CSI-RSs transmitted in each slot is the same, Y=Z=64 / 2 or 128 / 2 port CSI-RS can be set.

[0158] (2) Option 2. Frequency domain density reduction

[0159] Figures 13 to 15 illustrate an example for option 2 of proposal 2. Specifically, (i) Figure 13 illustrates 64 port CSI-RS as an example for option 2. (ii) Figure 14 illustrates 64 port CSI-RS with 0.5 CSI-RS density (port / RE / RB) as an example for option 2. In Figure 14, the density is 64-port / 64-RE / 2-RB = 0.5 port / RE / RB. (iii) Figure 15 illustrates 128 port CSI-RS with 0.25 CSI-RS density (port / RE / RB) as an example for option 2. In Figure 15, the density is 128-port / (16*8)-RE / 4-RB = 0.25 port / RE / RB.

[0160] Among multiple CDM-X groups (e.g., X = 2 or 4 or 8 or 16) that constitute 64 or 128 port CSI-RS, the first set of Y CDM groups is transmitted in an even PRB, and the second set of Z CDM groups is transmitted in an odd PRB. Here, X*(Y+Z) = P (64 or 128). As a special case of the above example, if the number of ports of CSI-RS transmitted in each slot is the same, Y=Z=64 / 2 or 128 / 2 port CSI-RS can be set.

[0161] In the case of the above proposal 2, the number of REs per PRB occupied by 64 port CSI-RS and 128 port CSI-RS is too large, so this is a measure to effectively reduce RS overhead.

[0162] In FIGS. 11 to 13, it is assumed that the base station instructs / configures different CDM configurations for each PRB of different frequency / time resources. However, in order to reduce signaling / configuration overhead, it may be considered that the CDM group configuration pattern of one PRB is repeated, as in FIG. 14. The configuration in FIG. 14 means that if a CSI-RS configuration for an even (odd) PRB is given (configuration / instruction for 4 CDM-8s in FIG. 14 and the total number of CSI-RS ports (64-port CSI-RS) and / or CSI-RS density), the CSI-RS pattern is repeatedly configured for the odd (even) PRB. This was explained based on option 2, but can also be extended to option 1.

[0163] In Fig. 11, CSI-RSs corresponding to the 1st CDM-8 to the 4th CDM-8 (n-th slot CSI-RS) may correspond to one CSI-RS resource #1, and CSI-RSs corresponding to the 5th CDM-8 to the 8th CDM-8 ((n+k)th slot CSI-RS) may correspond to CSI-RS resource #2. Extending the above example, CSI-RS resources #1, #2, ...#N aggregated for 64 port or 128 port CSI-RS configuration may be set / transmitted in different time slots. Alternatively, the plurality of resources may be grouped and transmitted in different time slots for each group. As also shown in Proposal 3 described below, when multiple CSI-RSs are aggregated to form 64 ports or 128 ports and transmitted across multiple slots, one resource is set to be transmitted within the same slot or T slots / symbols in consideration of channel coherence time. For example, according to the embodiment where k is fixed to 1 as described above, T may correspond to two consecutive slots. The reason why such a constraint is necessary is that when CSI-RS resources are transmitted in slots that are far apart from each other in the time domain, the coherency property may not be maintained between these CSI-RS resources, and acquiring CSI based on the aggregation of CSI-RS resources may be inaccurate / inappropriate.On the other hand, if all CSI-RS resources are mapped to the same slot, the coherency property can be maintained, but the increased number of ports, such as 64 or 128 ports, can cause excessive overhead for the CSI-RS in the slot, which may prevent other signals / channels from being transmitted or cause conflicts with them. To compromise the benefits of overhead reduction and coherence, aggregated CSI-RS resources within the coherence time corresponding to T slots can be mapped with a lower time domain density.

[0164] For example, the T value may be a value configured by the base station, set based on coherence time, or determined by the terminal's capability report. In the case of determining by coherence time, the T value may be determined, for example, as in Equation 1.

[0165]

[0166] In Equation 1, fm is the maximum Doppler spread, v is the velocity, and λ is the wavelength. Alternatively, the terminal can measure the channel based on the TRS, and the base station can set the T value based on the TDCP (time domain channel property) report, which is a report on the correlation measurement value.

[0167] In Fig. 13 / 14, a CSI-RS density of, for example, 0.5 port / RE / RB is considered, where all 64 or 128 ports are repeatedly transmitted every 2 PRBs. Here, the PRBs to which the 1st to 4th CDM-8 belong have a PRB offset value of 0, and the PRBs to which the 5th to 8th CDM-8 belong are examples where the offset value is 1. In other words, the CSI-RS resources corresponding to the 1st to 4th CDM-8 can be transmitted only in even PRBs, and the CSI-RS resources corresponding to the 5th to 8th CDM-8 can be transmitted only in odd PRBs. In the above case, since both consecutive PRBs are used, additional offset signaling is not necessary. However, for further RS ​​overhead reduction, a CSI-RS density of a smaller value (e.g., 0.25) can be considered for configuring / instructing the 64 or 128 ports. In this case, it means that 64 port or 128 port CSI-RS is repeated every 4 PRBs. In the case of the 0.25 density, two levels of PRB offset values ​​may be required to indicate this. For example, the first PRB offset (e.g., PRBs to which 1st to 4th CDM-8 belong in the example of FIG. 14) may be indicated by one of three values: 0, 1, 2, and the second offset (e.g., PRBs to which 5th to 8th CDM-8 belong in the example of FIG. 14) may be indicated by one of three values: 1, 2, 3. Alternatively, a method of jointly indicating two offsets, such as (0,1), (0,2), (0,3), (1,2), (1,3), (2,3), can also be considered.

[0168] Another way to set the CSI-RS density to 0.25 is to set 32 ​​port CSI-RS to PRB offset 0, 32 port CSI-RS to PRB offset 1, 32 port CSI-RS to PRB offset 2, and 32 port CSI-RS to PRB offset 3, for example, in the case of 128 ports. In this case, signaling for the PRB offset is not necessary, as illustrated in FIG. 15. Generalizing FIGS. 14 and 15, in the case of P port CSI-RS, as many CSI-RS ports as P * CSI-RS density are mapped to each PRB with a PRB offset of 1 to configure P port. This has the advantage of being able to reuse the existing CSI-RS configuration, and thus, there is no need for RS density and PRB offset signaling. In FIGS. 14 / 15, CSI-RS ports set to different PRB offsets can be distinguished as different CSI-RS resources.

[0169] A method of maximizing configuration flexibility by setting different time / frequency resources by combining the above options 1 and 2 can also be considered. For example, the CSI-RSs of the nth slot in FIG. 11 (e.g., PRBs to which the 1st to 4th CDM-8 belongs) can be transmitted every even PRB, and the CSI-RSs of the n+kth slot (e.g., PRBs to which the 5th to 8th CDM-8 belongs) can be transmitted every odd PRB.

[0170] Meanwhile, instead of designing a new 64-port / 128-port CSI-RS, one could consider designing a 64-port / 128-port CSI-RS by aggregating multiple legacy CSI-RS configurations. For example, two legacy 32-port CSI-RS resources could be aggregated to form a 64-port configuration, or four resources could be aggregated to form a 128-port configuration. In this case, CSI-RS port indexing could also be considered to ensure matching between the aggregated CSI-RS and the codebook ports.

[0171] Proposal 3

[0172] When configuring a 64 port / 128 port CSI-RS by aggregating legacy CSI-RSs, the port indexing in the following mathematical expression 2 is followed.

[0173]

[0174] In Equation 2, N represents # of CSI-RS ports per resource, K represents # of aggregated CSI-RS resources, L∈{1,2,4,8} represents CDM group size, and s represents sequence index within the CDM group.

[0175] In the case of the above proposal 3, it is a formula in which port indexing is performed while multiple CSI-RS resources are sequentially aggregated. For example, when two 32-port CSI-RSs are aggregated, the first resource is indexed from 3000 to 3031, and the second resource is indexed from 3032 to 3063. In this case, which CSI-RS resource is indexed first (index k) can be indexed in the order in which the base station configures the CSI-RS resources in the CSI-RS resource Config, or can be indexed in the lowest / highest order based on the CSI-RS resource ID. Alternatively, in the overhead reduction in the above proposal 2, indexing can be performed in the order of the CSI-RS resources configured in the lowest / highest PRB or slot based on the reference PRB (k=0) or the reference slot n. For example, in FIG. 15, if CSI-RSs composed of 1st-4th CDM-8 are configured as the second CSI-RS resource, CSI-RSs composed of 5th-8th CDM-8 are configured as the first CSI-RS resource, CSI-RSs composed of 9th-12th CDM-8 are configured as the third CSI-RS resource, and CSI-RSs composed of 13th-16th CDM-8 are configured as the fourth CSI-RS resource, the indexing order is 2nd→1st→3rd→4th CSI-RS resource. In addition, CSI-RS port indexing within each resource is indexed by the formula s+jL above.

[0176] As another example, when multiple CSI-RS resources are configured together in one PRB, CSI-RS port indexing is performed in the order of the resource to which the lowest / highest symbol index or the lowest / highest subcarrier index belongs among the REs occupied by the CSI-RSs in each resource. In Fig. 16, CSI-RS resource #2 is indexed first, and then CSI-RS resource #1 is indexed.

[0177] As another example, by reordering the CDM-groups composed of the aggregated CSI-RSs, port indexing can be performed in the order of the CDM-group index. The order of indexing the CDM groups is reordered in the order of frequency → time. For example, in the case of FIG. 16, the 1st CDM-8 to the 4th CDM-8 of CSI-RS resource #2 become the 1st CDM-8 to the 4th CDM-8, and the 1st CDM-8 to the 4th CDM-8 of CSI-RS resource #1 become the 5th CDM-8 to the 8th CDM-8. According to an example of Fig. 17, the order of the CDM group is 1st - 4th CDM-4 of CSI-RS resource #1 → 1st - 4th CDM-4 of CSI-RS resource #2 → 5th - 8th CDM-4 of CSI-RS resource #1 → 5th - 8th CDM-4 of CSI-RS resource #2, and the CDM group is reordered in this order. In this case, the formula has the advantage of being able to follow the legacy formula (p = 3000 + s + jL ). In addition, in the case of Proposal 3, if multiple resources have different numbers of ports, for example, if the 64 port configuration is CSI-RS resource #1 (32 ports) + CSI-RS resource #2 (16 ports) + CSI-RS resource #3 (16 ports), the above formula can be borrowed as is. However, in this case, the order of resource aggregation can be port indexing in the order of large / small port numbers.

[0178] Meanwhile, reusing legacy CSI-RSs means that specific CSI-RS resources are configured for legacy UEs, and since the base station is equipped with a cross-pol antenna, CSI-RSs corresponding to two poles are transmitted within one resource, and the codebook is configured accordingly. For example, in the example of a 32-port configuration as in FIG. 18, the first 16 ports correspond to the " / " slant, and the remaining 16 ports correspond to the "\" slant. Therefore, the codebook is also designed in a block diagonal form to apply a DFT vector to each port corresponding to each slant.

[0179] However, if Proposal 3 is followed, port indexing is performed sequentially for each CSI-RS resource, so although the CSI-RS is actually mapped to a cross-pol, due to the indexing, it can only be mapped to the same slant. To this end, the following port indexing is proposed.

[0180] Proposal 3-1

[0181] When configuring a 64 port / 128 port CSI-RS by aggregating legacy CSI-RSs, the port indexing in Equation 3 is followed.

[0182]

[0183] The ordering (index k) of the CSI-RS resources aggregated in Equation 3 can be directly borrowed from the method of Proposal 3.

[0184] According to Equation 3, half of the ports in the aggregated CSI-RS resource are mapped to the " / " slant, and the remaining ports are mapped to the "\" slant.

[0185] Fig. 19 is an example of a 64-port CSI-RS configuration and port indexing by aggregating two legacy 32-port CSI-RSs. In Fig. 19, (a) is a 64-port CSI-RS configured by aggregating two legacy 32-port CSI-RSs, (b) is port indexing according to Proposal 3, and (c) is port indexing according to Proposal 3-1. In Fig. 19, assuming that legacy UEs are also supported at the same time, it is illustrated that each legacy CSI-RS supports a legacy 32-port UE. If only the legacy CSI-RS configuration is reused, and the actual port mapping is CSI-RS resource #1 in the " / " slant and CSI-RS resource #2 in the "\" slant, the result of Proposal 3 is as shown in Fig. 19 (c). In addition, the port indexing method can be selectively used depending on the CSI reporting quantity or codebook structure. For example, in the case of Proposal 3, it is easy to apply to a multi-panel codebook when multiple CRIs (CSI-RS resource indicators) are selected from multiple CSI-RS resources and CSI (e.g., RI / CQI / PMI) is reported for each resource, and in the case of Proposal 3-1, it is easy to apply to a single-panel codebook consisting of 64 or 128 port CSI-RS.

[0186] In addition, if we generalize Proposal 3-1 to the case where multiple resources have different numbers of ports, we get Equation 4.

[0187]

[0188] ∑ k=0 K-1N k = P(64 / 128 port). In addition, although Equation 4 generalizes by assuming different CDM-sizes for each resource, if the CDM-sizes are different, power imbalance between ports may occur, so the CDM-size can be restricted to be the same across CSI-RS resources.

[0189] Additionally, when designing a multi-panel CSI codebook, ports belonging to the same panel can be restricted to be included in the same CDM group and / or the same CSI-RS resource, and ports belonging to different panels can be restricted to be included in different CDM groups and / or different CSI-RS resources. Similarly, when designing a single panel rank 3-4, two port sub-groups are considered for one panel, and according to the same principle as above, in the case of the same port sub-group, they can be restricted to be included in the same CDM group and / or CSI-RS resource.

[0190] In the above proposal, when multiple or single CSI-RS resources are transmitted across TDM across multi-slots or FDM across multi-PRM, the question arises: how to resolve collisions with other signals / channels. Here, resource collision refers to cases where some or all of a resource's time / frequency resources overlap. To address this collision, the following method is proposed.

[0191] # In case some of the resources that make up 64 / 128 CSI-RS collide with higher priority signals / channels (e.g., SSB, CORESET, DM-RS) than CSI-RS:

[0192] (1) Method 1: Drop all 64 / 128 port CSI-RS.

[0193] Even when multiple CSI-RS resources are aggregated to form a 64 / 128 port CSI-RS, all of the multiple resources are dropped.

[0194] (2) Method 2: Among the multiple resources that constitute the 64 / 128 port CSI-RS, all ports within the overlapping resources are dropped.

[0195] For example, when two resources are aggregated to form 64 ports (e.g., 32+32), if the ports corresponding to the second 32-port CSI-RS resource overlap, 32 ports are dropped, and only the remaining 32-port CSI-RS is transmitted. In this case, even if the terminal is configured with 64 ports, the report is performed for the 32-port CSI-RS. The terminal can determine whether specific ports are dropped based on a predefined priority rule, or the base station can notify the terminal of whether or not to drop them through a separate instruction.

[0196] (3) Method 3: Among the multiple resources that constitute the 64 / 128 port CSI-RS, overlapping resources are transmitted by performing time domain and / or frequency domain shift.

[0197] Among the CSI-RS resources that constitute a single or multiple 64 / 128 port CSI-RSs, collided resources are promised to be transmitted with a shift in the time axis or frequency axis (based on a predefined rule). The base station can configure whether the C symbol / slot and / or D RE / RB are shifted in the time / frequency axis. Alternatively, it can be determined to be located within the above-described coherence time.

[0198] (4) Method 4: The terminal does not expect the configured / transmitted CSI-RS resources to collide with channels / signals with higher priority than the CSI-RS. Furthermore, when configuring a 64-port or 128-port CSI-RS by aggregating multiple CSI-RS resources, the terminal does not expect collisions among the individual resources. For example, multiple CSI-RS resources are not configured / indicated to overlap with each other within a time / frequency resource.

[0199] Figure 20 illustrates examples of base station and terminal operation procedures for Proposals 1 / 2 / 3 / 3-1. Some terminal / base station operations may be omitted in Figure 20.

[0200] Referring to FIG. 20, the terminal can transmit a UE capability report including the number of supportable CSI-RS ports and the total number of simultaneously supportable CSI-RS ports to the base station (2005).

[0201] The terminal can receive configuration information related to CSI-RS and configuration information related to CSI reporting from the base station (2010).

[0202] The terminal can receive CSI-RS from the base station (2015) and measure / predict / calculate CSI based on this (2020).

[0203] The terminal can report measured / predicted / calculated CSI to the base station (2025).

[0204] The terminal can receive scheduling information (e.g., DCI) for a downlink channel (e.g., PDCCH, PDSCH) from the base station (2030).

[0205] The terminal can receive a downlink channel / signal transmitted by the base station (2035).

[0206] FIG. 21 illustrates a flow of a method performed by a terminal according to one embodiment.

[0207] Referring to FIG. 21, the terminal can receive CSI-RS (channel state information - reference signal) settings through upper layer signaling (2105).

[0208] The terminal can receive CSI-RS based on the above CSI-RS settings (2110).

[0209] The terminal can obtain CSI based on the above CSI-RS (2115).

[0210] The above CSI-RS is provided through P antenna ports, where P may be an integer greater than 32 and not exceeding 128.

[0211] The above CSI-RS configuration may include configurations for a plurality of CSI-RS resources related to the P antenna ports.

[0212] The configuration for the above multiple CSI-RS resources may include information about the slot offset value of each CSI-RS resource.

[0213] The above plurality of CSI-RS resources can be mapped within a time interval corresponding to T slots based on the slot offset value.

[0214] The above T slots can be two consecutive slots.

[0215] The above P can be 64 or 128.

[0216] Each CSI-RS resource can be mapped to one of the two slots based on the slot offset value.

[0217] The CSI can be acquired based on the aggregation of CSI-RS resources mapped to the first slot among the two slots and CSI-RS resources mapped to the second slot.

[0218] The above slot offset value can be 0 or 1.

[0219] The density of the CSI-RS, which is determined based on the number P of the antenna ports for the CSI-RS, the number of REs (resource elements) and the number of RBs (resource blocks), may be 0.5.

[0220] Each CSI-RS resource can be mapped to either an even physical resource block (PRB) or an odd PRB in the frequency domain.

[0221] Among the plurality of CSI-RS resources, a first CSI-RS resource may be mapped to an even PRB of a first slot among the T slots, and a second CSI-RS resource may be mapped to an odd PRB of a second slot among the T slots.

[0222] The terminal may not expect the plurality of CSI-RS resources to collide with other signals having a higher priority than the CSI-RS.

[0223] The above CSI-RS may be an aperiodic CSI-RS.

[0224] FIG. 22 illustrates a flow of a method performed by a base station according to one embodiment.

[0225] Referring to FIG. 22, the base station can transmit CSI-RS (channel state information - reference signal) settings to the terminal through upper layer signaling (2205).

[0226] The base station can transmit CSI-RS to the terminal based on the CSI-RS settings (2210).

[0227] The base station can receive a CSI report from the terminal (2215).

[0228] The above CSI-RS is provided through P antenna ports, where P may be an integer greater than 32 and not exceeding 128.

[0229] The above CSI-RS configuration may include configurations for a plurality of CSI-RS resources related to the P antenna ports.

[0230] The configuration for the above multiple CSI-RS resources may include information about the slot offset value of each CSI-RS resource.

[0231] The above plurality of CSI-RS resources can be mapped within a time interval corresponding to T slots based on the slot offset value.

[0232] The above T slots can be two consecutive slots.

[0233] The above P can be 64 or 128.

[0234] Each CSI-RS resource can be mapped to one of the two slots based on the slot offset value.

[0235] The above CSI report may include CSI obtained based on an aggregation of CSI-RS resources mapped to a first slot among the two slots and CSI-RS resources mapped to a second slot.

[0236] The above slot offset value can be 0 or 1.

[0237] The density of the CSI-RS, which is determined based on the number P of the antenna ports for the CSI-RS, the number of REs (resource elements) and the number of RBs (resource blocks), may be 0.5.

[0238] Each CSI-RS resource can be mapped to either an even physical resource block (PRB) or an odd PRB in the frequency domain.

[0239] Among the plurality of CSI-RS resources, a first CSI-RS resource may be mapped to an even PRB of a first slot among the T slots, and a second CSI-RS resource may be mapped to an odd PRB of a second slot among the T slots.

[0240] The base station can schedule the plurality of CSI-RS resources so that they do not collide with other signals having a higher priority than the CSI-RS.

[0241] The above CSI-RS may be an aperiodic CSI-RS.

[0242] Fig. 23 illustrates a communication system (1) applicable to various embodiments.

[0243] Referring to FIG. 23, 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.

[0244] 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).

[0245] 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.

[0246] Figure 24 illustrates a wireless device that can be applied to various embodiments.

[0247] Referring to FIG. 24, 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. 23.

[0248] 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.

[0249] 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.

[0250] 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.

[0251] 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.

[0252] 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.

[0253] 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.

[0254] Figure 25 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 23).

[0255] Referring to FIG. 25, the wireless device (100, 200) corresponds to the wireless device (100, 200) of FIG. 24 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. 24. For example, the transceiver(s) (114) may include one or more transceivers (106, 206) and / or one or more antennas (108, 208) of FIG. 24. 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).

[0256] 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. 23, 100a), a vehicle (Fig. 23, 100b-1, 100b-2), an XR device (Fig. 23, 100c), a portable device (Fig. 23, 100d), a home appliance (Fig. 23, 100e), an IoT device (Fig. 23, 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. 23, 400), a base station (Fig. 23, 200), a network node, etc. Wireless devices may be mobile or stationary depending on the use / service.

[0257] In FIG. 25, various elements, components, units / parts, and / or modules within the wireless device (100, 200) may be entirely interconnected via a wired interface, or at least some may be wirelessly connected via a communication unit (110). For example, within the wireless device (100, 200), the control unit (120) and the communication unit (110) may be wired, and the control unit (120) and a first unit (e.g., 130, 140) may be wirelessly connected via the communication unit (110). In addition, each element, component, unit / part, and / or module within the wireless device (100, 200) may further include one or more elements. For example, the control unit (120) may be composed of a set of one or more processors. For example, the control unit (120) may be composed of a set of a communication control processor, an application processor, an electronic control unit (ECU), a graphics processing processor, a memory control processor, etc. As another example, the memory unit (130) may be composed of RAM (Random Access Memory), DRAM (Dynamic RAM), ROM (Read Only Memory), flash memory, volatile memory, non-volatile memory, and / or a combination thereof.

[0258] Figure 26 illustrates a vehicle or autonomous vehicle applicable to various embodiments. The vehicle or autonomous vehicle may be implemented as a mobile robot, car, train, manned or unmanned aerial vehicle (AV), ship, etc.

[0259] Referring to FIG. 26, 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. 25, respectively.

[0260] 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.

[0261] 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.

[0262] The embodiments described above are combinations of components and features of the present invention in a predetermined form. Each component or feature should be considered optional unless explicitly stated otherwise. Each component or feature may be implemented without being combined with other components or features. Furthermore, it is also possible to form an embodiment of the present invention by combining some components and / or features. The order of operations described in the embodiments of the present invention may be changed. Some components or features of one embodiment may be included in another embodiment or may be replaced with corresponding components or features of another embodiment. It is self-evident that claims that do not have an explicit citation relationship in the patent claims may be combined to form an embodiment or may be incorporated as a new claim through a post-application amendment.

[0263] 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.

[0264] 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 CSI-RS (channel state information - reference signal) configuration via upper layer signaling; Receive CSI-RS based on the above CSI-RS settings; and Including obtaining CSI based on the above CSI-RS, The above CSI-RS is provided through P antenna ports, where P is an integer greater than 32 and not exceeding 128, The above CSI-RS configuration includes configurations for multiple CSI-RS resources related to the P antenna ports, The configuration for the above multiple CSI-RS resources includes information on the slot offset value of each CSI-RS resource, A method wherein the above plurality of CSI-RS resources are mapped within a time interval corresponding to T slots based on the slot offset value.

2. In paragraph 1, The above T slots are two consecutive slots, The above P is 64 or 128.

3. In paragraph 2, A method wherein each CSI-RS resource is mapped to one of the two slots based on the slot offset value.

4. In paragraph 3, A method in which the CSI is obtained based on an aggregation of CSI-RS resources mapped to a first slot among the two slots and CSI-RS resources mapped to a second slot.

5. In paragraph 3, The above slot offset value is 0 or 1.

6. In paragraph 1, The density of the CSI-RS, which is determined based on the number P of the antenna ports for the CSI-RS, the number of REs (resource elements) and the number of RBs (resource blocks), is 0.5, A method in which each CSI-RS resource is mapped to either an even physical resource block (PRB) or an odd PRB in the frequency domain.

7. In paragraph 6, A method wherein a first CSI-RS resource among the plurality of CSI-RS resources is mapped to an even PRB of a first slot among the T slots, and a second CSI-RS resource is mapped to an odd PRB of a second slot among the T slots.

8. In paragraph 1, A method wherein the terminal does not expect the plurality of CSI-RS resources to collide with other signals having higher priority than the CSI-RS.

9. In paragraph 1, A method wherein the above CSI-RS is aperiodic CSI-RS.

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

11. In the device, memory for storing commands; and A processor for performing operations by executing the above instructions, The operations of the above processor are: Receive CSI-RS (channel state information - reference signal) configuration via upper layer signaling; Receive CSI-RS based on the above CSI-RS settings; and Including obtaining CSI based on the above CSI-RS, The above CSI-RS is provided through P antenna ports, where P is an integer greater than 32 and not exceeding 128, The above CSI-RS configuration includes configurations for multiple CSI-RS resources related to the P antenna ports, The configuration for the above multiple CSI-RS resources includes information on the slot offset value of each CSI-RS resource, A device wherein the above plurality of CSI-RS resources are mapped to time intervals corresponding to T slots based on the slot offset value.

12. In paragraph 11, The above device further comprises a transceiver, The above device is a terminal operating in a wireless communication system.

13. In paragraph 11, The above device is a processing device configured to control a terminal operating in a wireless communication system.

14. In a method performed by a base station, Transmit CSI-RS (channel state information - reference signal) settings to the terminal via upper layer signaling; Transmitting CSI-RS to the terminal based on the above CSI-RS settings; and Including receiving a CSI report from the terminal, The above CSI-RS is provided through P antenna ports, where P is an integer greater than 32 and not exceeding 128, The above CSI-RS configuration includes configurations for multiple CSI-RS resources related to the P antenna ports, The configuration for the above multiple CSI-RS resources includes information on the slot offset value of each CSI-RS resource, A method wherein the above plurality of CSI-RS resources are mapped within a time interval corresponding to T slots based on the slot offset value.

15. At the base station, memory for storing commands; and A processor for performing operations by executing the above instructions, The operations of the above processor are: Transmit CSI-RS (channel state information - reference signal) settings to the terminal via upper layer signaling; Transmitting CSI-RS to the terminal based on the above CSI-RS settings; and Including receiving a CSI report from the terminal, The above CSI-RS is provided through P antenna ports, where P is an integer greater than 32 and not exceeding 128, The above CSI-RS configuration includes configurations for multiple CSI-RS resources related to the P antenna ports, The configuration for the above multiple CSI-RS resources includes information on the slot offset value of each CSI-RS resource, A base station, wherein the above plurality of CSI-RS resources are mapped within a time interval corresponding to T slots based on the slot offset value.

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