WO2024069780A1

WO2024069780A1 - Terminal, wireless communication method, and base station

Info

Publication number: WO2024069780A1
Application number: PCT/JP2022/036072
Authority: WO
Inventors: 祐輝松村; 聡永田; ジンワン; ランチン
Original assignee: 株式会社Ｎｔｔドコモ
Priority date: 2022-09-28
Filing date: 2022-09-28
Publication date: 2024-04-04

Abstract

A terminal according to one aspect of the present disclosure comprises: a reception unit that receives settings for one or more parameters related to the number of spatial domain basis vectors with respect to a plurality of transmission points; and a control unit for using the settings to determine the number of spatial domain basis vectors to be reported with respect to the plurality of transmission points. According to this aspect of this disclosure, an appropriate CSI/codebook for CJT can be determined.

Description

Terminal, wireless communication method and base station

This disclosure relates to terminals, wireless communication methods, and base stations in next-generation mobile communication systems.

Long Term Evolution (LTE) was specified for Universal Mobile Telecommunications System (UMTS) networks with the aim of achieving higher data rates and lower latency (Non-Patent Document 1). In addition, LTE-Advanced (3GPP Rel. 10-14) was specified for the purpose of achieving higher capacity and greater sophistication over LTE (Third Generation Partnership Project (3GPP (registered trademark)) Release (Rel.) 8, 9).

Successor systems to LTE (e.g., 5th generation mobile communication system (5G), 5G+ (plus), 6th generation mobile communication system (6G), New Radio (NR), 3GPP Rel. 15 and later, etc.) are also under consideration.

In future wireless communication systems (e.g., NR), it is being considered to report channel state information (CSI) based on the reception of a reference signal. It is also being considered to have multiple transmission/reception points (TRPs, Multi TRP (MTRP)) or multiple panels (multiple panels, multi-panel) perform DL transmission to a terminal (user terminal, User Equipment (UE)). Coherent joint transmission (CJT) using multiple TRPs/multiple panels is also being considered.

However, the CSI/codebook for CJT has not been fully considered. Unless such methods are clearly defined, there is a risk that communication throughput, communication quality, etc. will deteriorate.

Therefore, one of the objectives of this disclosure is to provide a terminal, a wireless communication method, and a base station that determine an appropriate CSI/codebook for CJT.

A terminal according to one embodiment of the present disclosure has a receiving unit that receives one or more parameter settings related to the number of spatial domain basis vectors for a plurality of transmission points, and a control unit that determines the number of spatial domain basis vectors to be reported for the plurality of transmission points based on the settings.

According to one aspect of the present disclosure, an appropriate CSI/codebook for CJT can be determined.

FIG. 1 shows an example of a 16-level quantization table. FIG. 2 shows an example of an 8-level quantization table. 3A and 3B show an example of an extended type 2-port selection codebook. 4A and 4B show an example of an extended type 2-port selection codebook. 5 shows an example of parameter combinations for a Rel.16 Type 2 codebook. 6 shows an example of parameter combinations for a Rel.17 type 2-port selective codebook. FIG. 7 shows an example of a combination of embodiment #1 and embodiment #2. FIG. 8 shows an example of a bitmap 3 according to embodiment #A1. FIG. 9 shows another example of bitmap 3 according to embodiment #A1. FIG. 10 shows an example of NZC according to embodiment #A2. FIG. 11 shows another example of an NZC according to embodiment #A. FIG. 12 is a diagram illustrating an example of a schematic configuration of a wireless communication system according to an embodiment. FIG. 13 is a diagram illustrating an example of the configuration of a base station according to an embodiment. FIG. 14 is a diagram illustrating an example of the configuration of a user terminal according to an embodiment. FIG. 15 is a diagram illustrating an example of the hardware configuration of a base station and a user terminal according to an embodiment. FIG. 16 is a diagram illustrating an example of a vehicle according to an embodiment.

(Multi-TRP)
In NR, one or more transmission/reception points (TRPs) (multi-TRPs (MTRPs)) are considered to perform DL transmission to a UE using one or more panels (multi-panels). It is also considered that a UE performs UL transmission to one or more TRPs using one or more panels.

Note that multiple TRPs may correspond to the same cell identifier (cell identifier (ID)) or different cell IDs. The cell ID may be a physical cell ID or a virtual cell ID.

The multi-TRP (TRP #1, #2) may be connected by an ideal/non-ideal backhaul to exchange information, data, etc. Each TRP of the multi-TRP may transmit a different code word (CW) and a different layer. Non-Coherent Joint Transmission (NCJT) may be used as one form of multi-TRP transmission.

In the NCJT, for example, TRP1 performs modulation mapping on a first codeword, performs layer mapping, and transmits a first PDSCH using a first number of layers (e.g., two layers) with a first precoding. TRP2 performs modulation mapping on a second codeword, performs layer mapping, and transmits a second PDSCH using a second number of layers (e.g., two layers) with a second precoding.

Note that multiple PDSCHs (multi-PDSCHs) that are NCJTed may be defined as partially or completely overlapping with respect to at least one of the time and frequency domains. In other words, the first PDSCH from the first TRP and the second PDSCH from the second TRP may overlap with each other in at least one of the time and frequency resources.

The first PDSCH and the second PDSCH may be assumed to be not quasi-co-located (QCL). Reception of multiple PDSCHs may be interpreted as simultaneous reception of PDSCHs that are not of a certain QCL type (e.g., QCL type D).

Multiple PDSCHs from a multi-TRP (which may be referred to as multiple PDSCHs) may be scheduled using one DCI (single DCI (S-DCI), single PDCCH) (single master mode). One DCI may be transmitted from one TRP of a multi-TRP. Multiple PDSCHs from a multi-TRP may be scheduled using multiple DCIs (multiple DCI (M-DCI), multiple PDCCH) (multiple master mode). Multiple DCIs may be transmitted from multiple TRPs. It may be assumed that the UE transmits separate CSI reports (CSI reports) for each TRP for different TRPs. Such CSI feedback may be referred to as separate feedback, separate CSI feedback, etc. In this disclosure, "separate" may be interchangeably read as "independent."

In addition, CSI feedback may be used to transmit CSI reports regarding both TRPs to one TRP. Such CSI feedback may be called joint feedback, joint CSI feedback, etc.

For example, in the case of separate feedback, the UE is configured to transmit a CSI report for TRP#1 using one PUCCH (PUCCH1) for TRP#1, and to transmit a CSI report for TRP#2 using another PUCCH (PUCCH2) for TRP#2. In the case of joint feedback, the UE transmits a CSI report for TRP#1 and a CSI report for TRP#2 for TRP#1 or #2.

Such a multi-TRP scenario allows for more flexible transmission control using channels with better quality.

(CSI report or reporting)
In Rel. 15 NR, a terminal (also referred to as a user terminal, User Equipment (UE), etc.) generates (also referred to as determining, calculating, estimating, measuring, etc.) channel state information (CSI) based on a reference signal (RS) (or a resource for the RS), and transmits (also referred to as reporting, feedback, etc.) the generated CSI to a network (e.g., a base station). The CSI may be transmitted to the base station, for example, using an uplink control channel (e.g., a Physical Uplink Control Channel (PUCCH)) or an uplink shared channel (e.g., a Physical Uplink Shared Channel (PUSCH)).

The RS used to generate the CSI may be, for example, at least one of a Channel State Information Reference Signal (CSI-RS), a Synchronization Signal/Physical Broadcast Channel (SS/PBCH) block, a Synchronization Signal (SS), a DeModulation Reference Signal (DMRS), etc.

The CSI-RS may include at least one of a Non-Zero Power (NZP) CSI-RS and a CSI-Interference Management (CSI-IM). The SS/PBCH block is a block including an SS and a PBCH (and corresponding DMRS), and may be referred to as an SS block (SSB), etc. The SS may also include at least one of a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS).

The CSI may include at least one of a Channel Quality Indicator (CQI), a Precoding Matrix Indicator (PMI), a CSI-RS Resource Indicator (CRI), a SS/PBCH Block Resource Indicator (SSBRI), a Layer Indicator (LI), a Rank Indicator (RI), L1-RSRP (Layer 1 Reference Signal Received Power), L1-RSRQ (Reference Signal Received Quality), L1-SINR (Signal to Interference plus Noise Ratio), and L1-SNR (Signal to Noise Ratio).

The UE may receive information regarding CSI reporting (report configuration information) and control CSI reporting based on the report configuration information. The report configuration information may be, for example, "CSI-ReportConfig" of the information element (IE) of Radio Resource Control (RRC). Note that in this disclosure, RRC IE may be interchangeably read as RRC parameters, higher layer parameters, etc.

The reporting configuration information (e.g., the RRC IE "CSI-ReportConfig") may include, for example, at least one of the following:
Information regarding the type of CSI report (report type information, e.g., RRC IE "reportConfigType")
Information on one or more quantities of CSI to be reported (one or more CSI parameters) (report quantity information, e.g., RRC IE “reportQuantity”)
Information on the RS resource used to generate the amount (the CSI parameter) (resource information, for example, "CSI-ResourceConfigId" of the RRC IE)
Information on the frequency domain to which the CSI is reported (frequency domain information, for example, the RRC IE "reportFreqConfiguration")

For example, the report type information may indicate a periodic CSI (Periodic CSI (P-CSI)) report, an aperiodic CSI (A-CSI) report, or a semi-persistent CSI (Semi-Persistent CSI (SP-CSI)) report.

The reporting amount information may also specify a combination of at least one of the above CSI parameters (e.g., CRI, RI, PMI, CQI, LI, L1-RSRP, etc.).

The resource information may also be an ID of a resource for the RS. The resource for the RS may include, for example, a non-zero power CSI-RS resource or SSB, and a CSI-IM resource (for example, a zero power CSI-RS resource).

The frequency domain information may also indicate the frequency granularity of the CSI reporting. The frequency granularity may include, for example, a wideband and a subband. The wideband is the entire CSI reporting band. The wideband may be, for example, the entirety of a certain carrier (Component Carrier (CC)), cell, serving cell), or the entirety of a bandwidth part (BWP) within a certain carrier. The wideband may also be referred to as the CSI reporting band, the entire CSI reporting band, etc.

Furthermore, a subband may be a part of a wideband and may be composed of one or more resource blocks (RBs or PRBs). The size of the subband may be determined according to the size of the BWP (number of PRBs).

The frequency domain information may indicate whether wideband or subband PMI is to be reported (the frequency domain information may include, for example, the RRC IE "pmi-FormatIndicator" used to determine whether wideband PMI reporting or subband PMI reporting is to be performed). The UE may determine the frequency granularity of the CSI report (i.e., whether wideband PMI reporting or subband PMI reporting) based on at least one of the above reporting amount information and frequency domain information.

If wideband PMI reporting is configured, one wideband PMI may be reported for the entire CSI reporting band, whereas if subband PMI reporting is configured, a single wideband indication i ₁ may be reported for the entire CSI reporting band, and one subband indication i ₂ (e.g., one subband indication for each subband) may be reported for each of the one or more subbands within the entire CSI reporting band.

The UE performs channel estimation using the received RS and estimates the channel matrix H. The UE feeds back an index (PMI) that is determined based on the estimated channel matrix.

The PMI may indicate a precoder matrix (also referred to simply as a precoder) that the UE considers appropriate to use for downlink (DL) transmissions to the UE. Each value of the PMI may correspond to one precoder matrix. A set of PMI values may correspond to a set of different precoder matrices, called a precoder codebook (also referred to simply as a codebook).

In the space domain, the CSI report may include one or more types of CSI. For example, the CSI may include at least one of a first type (Type 1 CSI) used for selecting a single beam and a second type (Type 2 CSI) used for selecting multiple beams. Single beam may be rephrased as a single layer, and multiple beams may be rephrased as multiple beams. In addition, Type 1 CSI does not assume multi-user multiple input multiple output (MU-MIMO), and Type 2 CSI may assume multi-user MIMO.

The codebook may include a codebook for type 1 CSI (also called a type 1 codebook, etc.) and a codebook for type 2 CSI (also called a type 2 codebook, etc.). Type 1 CSI may also include type 1 single-panel CSI and type 1 multi-panel CSI, and different codebooks (type 1 single-panel codebook, type 1 multi-panel codebook) may be defined for each.

In this disclosure, Type 1 and Type I may be interpreted as interchangeable. In this disclosure, Type 2 and Type II may be interpreted as interchangeable.

The uplink control information (UCI) type may include at least one of the following: Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK), scheduling request (SR), and CSI. The UCI may be carried by the PUCCH or the PUSCH.

In Rel. 15 NR, UCI may contain one CSI part for wideband PMI feedback. CSI report #n contains PMI wideband information if reported.

In Rel. 15 NR, UCI can contain two CSI parts for subband PMI feedback. CSI part 1 contains wideband PMI information. CSI part 2 contains one wideband PMI information and some subband PMI information. CSI part 1 and CSI part 2 are coded separately.

In Rel. 15 NR, the UE is configured by a higher layer with N (N≧1) CSI reporting configuration report settings and M (M≧1) CSI resource configuration resource settings. For example, the CSI reporting configuration (CSI-ReportConfig) includes channel measurement resource settings (resourcesForChannelMeasurement), interference CSI-IM resource settings (csi-IM-ResourceForInterference), interference NZP-CSI-RS settings (nzp-CSI-RS-ResourceForInterference), and report quantity (reportQuantity). Each of the channel measurement resource settings, interference CSI-IM resource settings, and interference NZP-CSI-RS settings is associated with a CSI resource configuration (CSI-ResourceConfig, CSI-ResourceConfigId). The CSI resource configuration includes a list of CSI-RS resource sets (csi-RS-ResourceSetList, e.g., an NZP-CSI-RS resource set or a CSI-IM resource set).

For both FR1 and FR2, evaluation and provision of CSI reporting for DL multi-TRP and multi-panel transmissions at least one is being considered to enable more dynamic channel/interference hypotheses for NCJT.

(Codebook settings)
The UE is configured with parameters related to the codebook (CodebookConfig) by higher layer signaling (RRC signaling). The codebook configuration is included in the CSI report configuration (CSI-ReportConfig) of the higher layer (RRC) parameters.

In the codebook setting, at least one codebook is selected from a number of codebooks including type 1 single panel (typeI-SinglePanel), type 1 multi-panel (typeI-MultiPanel), type 2 (typeII), and type 2 port selection (typeII-PortSelection).

The codebook parameters include parameters related to the codebook subset restriction (CBSR). The CBSR setting is a bit that indicates which PMI reports are allowed ('1') and which are not allowed ('0') for the precoder associated with the CBSR bit. One bit in the CBSR bitmap corresponds to one codebook index/antenna port.

(CSI Reporting Settings)
In addition to the codebook configuration (CodebookConfig), the CSI report configuration (CSI-ReportConfig) of Rel. 16 includes CSI-RS resources for channel measurement (resourcesForChannelMeasurement (CMR)), CSI-RS resources for interference measurement (csi-IM-ResourcesForInterference (ZP-IMR), nzp-CSI-RS-ResourcesForInterference (NZP-IMR)), etc. Among the parameters of CSI-ReportConfig, parameters other than codebookConfig-r16 are also included in the CSI report configuration of Rel. 15.

In Rel. 17, an extended CSI reporting configuration (CSI-ReportConfig) is being considered for CSI measurement/reporting of multi-TRP using NCJT. In this CSI reporting configuration, two CMR groups corresponding to each of the two TRPs are configured. The CMRs in the CMR group may be used for at least one measurement of multi-TRP and single-TRP using NCJT. The N CMR pairs of the NCJT are configured by RRC signaling. The UE may be configured by RRC signaling whether to use a CMR of a CMR pair for single-TRP measurement.

For CSI reporting related to multi-TRP/panel NCJT measurements configured through a single CSI reporting configuration, it is considered that at least one of the following

options

1 and 2 will be supported.

<Option 1>
The UE is configured to report X (X=0,1,2) CSIs related to single-TRP measurement hypotheses/hypotheses and one CSI related to NCJT measurements. If X=2, then two CSIs are related to two different single-TRP measurements using CMRs of different CMR groups.

<Option 2>
The UE may be configured to report one CSI associated with the best measurement result among the measurement hypotheses for the NCJT and single TRP.

As mentioned above, in Rel. 15/16, the CBSR is set for each codebook setting for each CSI reporting setting. In other words, the CBSR applies to all CMRs, etc. within the corresponding CSI reporting setting.

However, in the CSI reporting configuration for multi-TRP in Rel.17, when the above-mentioned

options

1 and 2 are applied, the following measurement configuration may be performed.
Option 1 (X=0): Measurement of NCJT CSI only.
Option 1 (X=1): Measurement of the CSI of the NCJT and the CSI of a single TRP.
Option 1 (X=2): Measurement of the CSI of the NCJT and the CSI of a single TRP (two TRPs).
Option 2: Measure both the CSI of the NCJT and the CSI of a single TRP.

(Type 1 Codebook)
Type 1 codebook (Rel. 15) specifies a type 1 single panel codebook and a type 1 multi-panel codebook for base station panels. In type 1 single panel, the number of CSI-RS antenna ports P _CSI-RS and the antenna model of the CSI antenna port array (logical configuration) are specified for (N ₁ , N ₂ ). In type 1 multi-panel, the number of CSI-RS antenna ports P _CSI-RS and the antenna model of the CSI antenna port array (logical configuration) are specified for (N _g , N ₁ , N ₂ ).

For Rel. 15 type 1 single panel CSI, the UE sets the upper layer parameter of codebook type (subType in type1 in codebookType in CodebookConfig) to type 1 single panel ('typeI-SinglePanel'). If the number of layers v is not {2,3,4}, the PMI values correspond to three codebook indices _i1,1 , _i1,2 , _i2 . If the number of layers v is not {2,3,4}, the PMI values correspond to four codebook indices _i1,1 , _i1,2 , _i1,3 , _i2 . If the number of layers v is not {2,3,4}, the composite codebook index _i1 = [ _i1,1 , _i1,2 ]. If the number of layers v is {2,3,4}, the composite codebook index _i1 = [ _i1,1 , _i1,2 , _i1,3 ].

For the number of CSI antenna ports P _CSI-RS , the supported settings (N ₁ ,N ₂ ) and (O ₁ ,O ₂ ) (combination of values) are specified. (N ₁ ,N ₂ ) indicates the number of antenna elements in two dimensions, and is set by n1-n2 in moreThanTwo in nrOfAntennaPorts in typeI-SinglePanel. (O ₁ ,O ₂ ) is the two-dimensional oversampling factor. i _1,1 , which corresponds to the horizontal beam, is {0,1,...,N ₁ O ₁ -1}. i _1,2, which corresponds to the vertical beam, is {0,1,...,N ₂ O ₂ -1}. i ₂ is {0,1,2,3}. For codebookMode=1, the matrix for one-layer CSI reporting codebook with 2999+P _CSI-RS from antenna port 3000 is W_i _1,1 ,i _1,2 ,i ₂ ^(1), where W _l,m,n ⁽¹⁾ is given by:

For Rel.15 Type-1 multi-panel CSI, compared to Type-1 single panel, the number of panels _Ng is set in addition to _N1 and _N2 . For inter-panel co-phasing (phase compensation between panels), i, _{1, and 4} are added and reported. The same SD beam (precoding matrix _Wl ) is selected for each panel, and only inter-panel co-phasing is added and reported.

For the number of CSI antenna ports P _CSI-RS , the supported settings (N _g , N ₁ , N ₂ ) and (O ₁ , O ₂ ) are specified in the specification. (N ₁ , N ₂ ) are set by ng-n1-n2 in typeI-MultiPanel. i _1,1 is {0,1,...,N ₁ O ₁ -1}. _{i 1,2} is {0,1,...,N ₂ O ₂ -1}. i _1,4,q is {0,1,2,3} for q=1,...,N _g -1. i ₂ is {0,1,2,3}. For codebookMode=1, the matrix for 1-layer CSI reporting codebook with 2999+P _CSI-RS from antenna port 3000 is _{W_i1,1} , _i1,2 , _i1,4 , _i2 ^(1), where Wl _,m,p,n ⁽¹⁾ =Wl _,m,p,n ^1, _Ng ,1.

W_l,m,p,n^1,N _g ,1 and W_l,m,p,n^2,N _g ,1 for N _g ={2,4} (matrix W _l,m,p,n ^1,2,1 for the first layer, N _g =2, codeBookMode=1, matrix W l,m,p,n ^2,2,1 for the second layer, N _g =2, codeBookMode=1, matrix W _l,m, _p,n ^1,4,1 for the first layer, N _g =4, codeBookMode=1, and matrix W _l,m,p,n ^2,4,1 for the second layer, N _g =4, codeBookMode=1) are given by the following equations.

where φ _n =e ^jπn/2 . For N _g =2, p=p ₁ , and for N _g =4, p=[p ₁ ,p ₂ ,p ₃ ]. φ_p ₁ , φ_p ₂ , φ_p ₃ represent inter-panel co-phasing. The same beams (SD beam matrix, precoding matrix W _l ) are selected for

panels

0, 1, 2, and 3, φ_p ₁ represents the phase compensation of panel 1 relative to panel 0, φ_p ₂ represents the phase compensation of panel 2 relative to panel 0, and φ_p ₃ represents the phase compensation of panel 3 relative to panel 0.

(Type 2 Codebook)
In this disclosure, a matrix Z with X rows and Y columns may be expressed as Z(X×Y).

In Type 2 CSI of Rel. 15, for a given layer k, the generation of a subband-wise (SB-wise) precoding vector is based on the following equation:
_Wk ( _Nt × _N3 ) = _W1W2 _,k (Y1)

N _t is the number of ports. N ₃ is the total number of precoding matrices (subbands) indicated by the PMI. W ₁ (N _t ×2L) is a matrix (SD beam matrix) consisting of L∈{2,4} (oversampled) spatial domain (SD) two-dimensional (2D) DFT vectors (SD beams, 2D-DFT vectors). L is the number of beams. For example, L=2 SD 2D-DFT vectors are b _i , b _j , respectively. W _2,k (2L×N ₃ ) is a matrix (LC coefficient matrix) consisting of linear combination coefficients (LC coefficients, subband complex LC coefficients, coupling coefficients) for layer k. W _2,k represents beam selection and co-phasing between the two polarizations. For example, the two W _2,k are c _i , c _j , respectively. For example, the channel vector h is approximated by a linear combination of L=2 SD 2D-DFT vectors, c _i b _i ,+c _j b _j . The feedback overhead is mainly due to the LC coefficient matrix W _2,k . Also, Type-2 CSI in Rel. 15 only supports

ranks

1 and 2.

In Type-2 CSI, the channel (channel matrix) for a user is represented by a linear combination of two polarizations and L beams (L 2D-DFT vectors). Rel. 15 Type-2 CSI supports ranks 1 and 2.

(Type 2 Codebook Extension)
Type-2 CSI (enhanced Type-2 codebook) in Rel. 16 reduces the overhead associated with W2 _,k through frequency domain (FD) compression. Type-2 CSI in Rel. 16 supports ranks 3 and 4 in addition to

ranks

1 and 2.

In Type 2 CSI of Rel. 16, for a given layer k, information based on the following formula is reported by the UE:
_Wk = _W1W ^~ ^kWf _,kH ₍ Y2)

W _2,k is approximated by W ^~ _k W _f,k ^H. The matrix W ^~ may be expressed as W with a ~ (w tilde) above it. W ^~ _k may be expressed as W ^~ _2,k . The matrix W _f,k ^H is the adjoint matrix of W _f,k and is obtained by conjugate transpose of W _f,k .

For CSI reporting, the UE may be configured with one of two subband sizes. The subband (CQI subband) is defined as N _PRB ^SB contiguous PRBs and may depend on the total number of PRBs in the BWP. The number of PMI subbands per CQI subband R is configured by the RRC IE (numberOfPMI-SubbandsPerCQI-Subband). R controls the total number of precoding matrices _N3 represented by the PMI as a function of the number of subbands configured in the csi-ReportingBand, the subband size configured by subbandSize, and the total number of PRBs in the BWP.

W ₁ (N _t ×2L) is a matrix consisting of multiple (oversampled) spatial domain (SD) 2D-DFT (vector, beam). For this matrix, multiple indices of the 2D discrete Fourier transform (2D-DFT) vector and the 2D over-sampling factor are reported. The spatial domain response/distribution represented by the SD 2D-DFT vector may be called the SD beam.

W ^~ _k (2L× _Mv ) is a matrix of LC coefficients for which up to _K0 non-zero coefficients (NZCs, LC coefficients with non-zero amplitude) are reported. The report consists of two parts: a bitmap capturing the NZC positions and the quantized NZCs.

W _f,k (N ₃ ×M _v ) is a matrix of frequency domain (FD) bases (vectors) for layer k. There are M _v FD bases (FD DFT bases) for each layer. If _{N 3} >19, M _v DFTs from an intermediate subset (InS) of size N ₃ '(<N ₃ ) are selected. If _{N 3} ≦19, log2(C(N ₃ -1,M _v -1)) bits are reported. Here, C(N ₃ -1,M _v -1) represents the number of combinations (combinatorial coefficient C(x,y)) of selecting M _v -1 from N ₃ -1, also called binomial coefficients. The frequency domain response/distribution (frequency response) represented by a linear combination of FD basis vectors and LC coefficients may be called an FD beam. The FD beam may correspond to a delay profile (time response).

The subset of FD bases is given as {f ₁ ,...,f _{M_v} }, where f _i is the ith FD basis for the kth layer, i∈{1,...,M _v }. The PMI subband size is given by CQI subband size/R, where R∈{1,2}. The number of FD bases M _v for a given rank v is given by ceil(p _v ×N ₃ /R). The number of FD bases is the same for all layers k∈{1,2,3,4}. p _v is set by the higher layer.

Each row of the matrix W2 _,k represents the channel frequency response of a particular SD beam. If the SD beam is highly directional, the channel taps per beam are limited (the power delay profile is sparse in the time domain). As a result, the channel frequency response per SD beam is highly correlated (approaching ^flat in the frequency domain). In this case, the channel frequency response can be approximated by a linear combination of a small number of FD bases. For example, if _Mv = 2, using the FD bases _f2 , _fq and LC coefficients _d10 ^, _d20 , the frequency response associated with SD _beam _b0 is approximated _by _d10f2 ⁺ , ^d20fq _.

The M _v FD bases with the highest gain are selected. By letting M _v ≪N ₃ , the overhead of W ^∼ _k is much smaller than that of W _2,k . All or a part of the M _v FD bases are used to approximate the frequency response of each SD beam. A bitmap is used to report only the FD bases selected for each SD beam. If no bitmap is reported, all FD bases are selected for each SD beam. In this case, the NZCs of all FD bases are reported for each SD beam. The maximum number of NZCs in one layer, K _k ^NZ ≦K ₀ =ceil(β×2LM _v ), and the maximum number of NZCs across all layers, K ^NZ ≦2K ₀ =ceil(β×2LM _v ), is set by the higher layer.

Each reported LC coefficient (complex coefficient) in {tilde over (W ^)} _k is represented by a separately quantized amplitude and phase.
[Amplitude quantization]
The polarization specific reference amplitude is 16-level quantized using the table of Figure 1 (multiple element mapping of amplitude coefficient indicator _i2,3,l : mapping of element kl _,p ⁽¹⁾ to amplitude coefficient _pl,p ⁽¹⁾ ). All other coefficients are 8-level quantized using the table of Figure 2 (multiple element mapping of amplitude coefficient indicator _i2,4,l : mapping of element kl _,i,f ⁽²⁾ to amplitude coefficient _pl,i,f ⁽²⁾ .
[Phase Quantization]
All coefficients are quantized using 16-PSK, e.g., φ _l,i = exp(j2πc _l,i /16), c _l,i ∈{0,...,15}, where c _l,i is the phase coefficient reported by the UE (using 4 bits) for the associated phase value φ _l,i .

　Type 2 CSI feedback on PUSCH in Rel. 16 includes two parts. CSI Part 1 has a fixed payload size and is used to identify the number of information bits in CSI Part 2. The size of Part 2 is variable (UCI size depends on the number of NZCs, which is not known to the base station). The UE reports the number of NZCs in CSI Part 1, which determines the size of CSI Part 2. After receiving CSI Part 1, the base station knows the size of CSI Part 2.

In enhanced Type-2 CSI feedback, CSI Part 1 includes RI, CQI, and an indication of the total number of non-zero amplitudes (NZC) across layers for enhanced Type-2 CSI. The fields in Part 1 are coded separately. CSI Part 2 includes PMI for enhanced Type-2 CSI.

Parts

1 and 2 are coded separately. CSI Part 2 (PMI) includes at least one of the following: oversampling factor, index of 2D-DFT basis, index M _initial of initial DFT basis (start offset) of selected DFT window, selected DFT basis per layer, NZC (amplitude and phase) per layer, strongest coefficient indicator (SCI) per layer, and strongest coefficient amplitude per layer/polarization.

The multiple PMI indices (PMI values, codebook indices) associated with different CSI Part 2 information may follow for the kth layer:
i _1,1 : Oversampling factor i _1,2 : Multiple index of 2D-DFT basis i _1,5 : Index (start offset) of initial DFT basis of selected DFT window M _initial
i _1,6,k : the DFT basis selected for the kth layer; i _1,7,k : the bitmap for the kth layer; i _1,8,k : the strongest coefficient indicator (SCI) for the kth layer.
_i2,3,k : the amplitude of the strongest coefficient (for both polarizations) of the kth layer; _i2,4,k : the amplitude of the reported coefficient of the kth layer; _i2,5,k : the phase of the reported coefficient of the kth layer.

_i1,5 and _i1,6,k are PMI indices for DFT basis reporting. _i1,5 is reported only if _N3 >19.

For a given CSI report, the PMI information is organized into three groups (groups 0 to 2) for CSI part 2 groupings. This is important in case of CSI omission. Each reported element with index _i2,4,l , _i2,5,l , and _i1,7,l is associated with a specific priority rule. Groups 0 to 2 follow:
Group 0: index _i1,1 , _i1,2 , _i1,8,l (l=1,...,v)
Group 1: the highest (top) _v2LMv -floor( ^KNZ /2) priority elements of index _i1,5 (if reported), _i1,6,l , and _i1,7,l (if reported), the highest (top) ceil(KNZ/2)-v priority elements of _i2,3,l , and _i2,4,l , and the highest (top) ceil( ^KNZ /2)-v priority elements of _i2,5,l (l=1,...,v) ^.
Group 2: The lowest (lowest) floor(K ^NZ /2) priority elements among i _{1, 7, l} , the lowest (lowest) floor(K ^NZ /2) priority elements among i _{2, 4, l} , the lowest (lowest) floor(K ^NZ /2) priority elements among i _{2, 5, l} (l=1,...,v)

In Type-1 CSI, an SD beam represented by an SD DFT vector is sent towards the UE. In Type-2 CSI, L SD beams are linearly combined and sent towards the UE. Each SD beam can be associated with multiple FD beams. For the corresponding SD beam, the channel frequency response can be obtained by linearly combining those FD basis vectors. The channel frequency response corresponds to the power delay profile.

The PMI of the extended type-2 codebook is represented by information fields _X1 and _X2 . The bit widths of _i1,1 , _i1,2 , _i1,8,1 , _i1,8,2 , _i1,8,3 , _i1,8,4 in information field _X1 are given by Fig. 3. _i1,1 , _i1,2 are the indices of the SD basis. _i1,8,1 , _i1,8,2 , _i1,8,3 , _i1,8,4 are the indices of the SCI per layer. The bit widths _of _i2,3,1 , _i2,3,2 , i2,3,3, _i2,3,4 , _i1,5 , _i1,6,1 , _i1,6,2 , _i1,6,3 , _i1,6,4 , { _i2,4 _,l } _l=1...v , { _i2,5,l } _l=1...v , { _i2,7,l } _l=1...v , in the information field X2 are given by Fig. 4. _i2,3,1 , _i2,3,2 , _i2,3,3 , _i2,3,4 are the amplitudes of the SCI per layer. _i1,5 is the window of the FD basis. _i1,6,1 , _i1,6,2 , _i1,6,3 , _i1,6,4 are the selected FD basis per layer. { _i2,4,l } _l=1...v are the amplitudes of the other (non-SCI) coefficients per layer. { _i2,5,l } _l=1...v are the phases of the other (non-SCI) coefficients per layer. { _i2,7,l } _l=1...v are the bitmaps for NZC.

(Type 2 Port Selection Codebook/Extension/Further Extension)
In Rel. 15 Type 2 port selection (PS) CSI (Type 2 PS codebook), the UE does not need to derive SD beams considering 2D-DFT as in Type 2 CSI. The base station transmits CSI-RS using K CSI-RS ports that are beamformed considering a set of SD beams. The UE selects/identifies the best L(≦K) CSI-RS ports per polarization and reports their indexes in _W1 . Rel. 15 Type 2 PS CSI supports

rank

1, 2.

The operation of Rel. 16 Type-2 PS CSI (enhanced Type-2 PS codebook) is similar to Rel. 16 Type-2 CSI, except for SD beam selection. Rel. 15 Type-2 PS CSI supports ranks 1 to 4.

For layer k ∈ {1, 2, 3, 4}, the subband (SB)-wise precoder generation is given by:
_Wk ( _Nt × _N3 ) = _QW1W ^~ _kWf _,kH ⁽ Y3)

where Q(N _t ×K) denotes the K SD beams used for CSI-RS beamforming. W ₁ (K×2L) is a block diagonal matrix. W ^∼ _k (2L×M) is the LC coefficient matrix. _{W f,k} (N ₃ ×M) consists of N ₃ DFT basis vectors (FD basis vectors). K is set by upper layers. L is set by upper layers. _{P CSI-RS} ∈{4,8,12,16,24,32}. If _{P CSI-RS} > 4, L∈{2,3,4}.

In Rel.15/16 Type-2 PS CSI, each CSI-RS port #i is associated with an SD beam (b _i ) (FIGS. 3A and 3B).

Rel. 16 Type-2 PS CSI reduces overhead compared to Rel. 15 Type-2 PS CSI by reducing the number of FD bases from _N3 to _Mv ( _Mv ≪ _N3 ) in the same manner as Rel. 16 Type-2 CSI.

In the Rel. 17 Type 2 port selection CSI/codebook (further enhanced Type 2 port selection codebook), each CSI-RS port #i is associated with an SD-FD beam pair (pair of SD beam b _i and FD beam f _i,j, where j is the frequency index) instead of an SD beam (FIGS. 4A and 4B). In this example,

ports

3 and 4 are associated with the same SD beam and different FD beams.

The frequency selectivity of the channel frequency response observed at the UE based on an SD beam-FD beam pair can be reduced by delay pre-compensation compared to the frequency selectivity of the channel frequency response observed at the UE based on an SD beam.

The main scenario for Type 2 port selection codebook in Rel. 17 is FDD. The channel reciprocity based on SRS measurement is not perfect (UL beam and DL beam angles may be different, UL and DL frequencies are different in FDD, and effective antenna spacing is different at the UL and DL frequencies). However, the base station can obtain/select some partial information (dominant angle and delay (SD beam and FD beam)). By using SRS measurement at the base station in addition to CSI report, the base station can obtain CSI for DL MIMO precoder decision. In this case, some CSI reports may be omitted to reduce CSI overhead.

In Rel. 17 Type-2 PS CSI, each CSI-RS port is beamformed using an SD beam and an FD basis vector. Each port is associated with an SD-FD pair.

For a given layer k, information based on the following equation may be reported by the UE:
_Wk (K× _N3 ) = _W1W ^~ ^kWf _,kH ₍ Y4)

For _W1 (K×2L), each matrix block consists of L columns of a K×K identity matrix. The base station transmits K beamformed CSI-RS ports. In the Rel. 16 Type-2 PS codebook, each port is associated with an SD beam. In contrast, in the Rel. 16 Type-2 PS codebook, each port is associated with an SD-FD pair. The UE selects L ports out of K and reports them to the base station as part of the PMI (W1 _,k ).

W̃ _k (2L×M _v ) is a matrix of LC coefficient (subband complex LC coefficient) vectors for layer k. At most K ₀ NZCs are reported. The report consists of ^two parts: a bitmap capturing the NZC positions and the quantized NZCs. In Rel. 16 Type-2 PS codebooks, the bitmap of NZC positions is always reported. In contrast, in Rel. 17 Type-2 PS codebooks, the bitmap can be omitted in certain cases. The specific case is when the number of reported NZCs is equal to the maximum number K ₁ *M*v (v≦2).

The precoding matrix indicated by the PMI is determined from L+M vectors, where L=K ₁ /2 is the number of SD beams (SD basis vectors), and K ₁ =αP _CSI-RS is the number of ports selected from the CSI-RS ports. The window size N for the selection of FD basis vectors may be configured using a higher layer parameter (valueOfN).

W _f,k (N ₃ ×M _v ) is a matrix consisting of M _v FD basis (FD DFT basis) vectors for layer k. M _v is 1 or 2. The base station can determine the presence or absence (on/off) of W _f,k . If W _f,k is on (M _v =2), M _v additional FD basis vectors are reported. If W _f,k is off (M _v =1, W _f,k is off, which is the same as M _v =1, W _f,k is on), no additional FD basis vectors are reported. If M _v =2, M _v FD basis vectors are selected/reported from the RRC-configured window size N (N is 2 or 4). In Rel. 16, W _f,k is always reported.

(Rel. 17 NCJT CSI)
A joint transmission (JT) may refer to simultaneous data transmission from multiple points (eg, TRPs) to a single UE.

Rel. 17 supports NCJT from two TRPs. PDSCHs from two TRPs may be precoded and decoded independently. Frequency resources may be non-overlapping, partially overlapping, or fully overlapping. In case of overlap, PDSCH from one TRP will interfere with PDSCH from the other TRP.

Applicable scenario is single DCI based MTRP NCJT with type 1 single panel codebook. For NCJT CSI measurements, two channel measurement resource (CMR) groups with each CMR from one TRP can be configured within a single CSI-ReportConfig. One CSI reporting mode can be configured from two modes.

By RRC signaling, the CSI-ReportConfig for Rel. 17 non-coherent joint transmission (NCJT) CSI configures the CMR and the CSI reporting mode (csi-ReportMode).

_Ks = _K1 + KTwo CMR groups with ₂ CMRs are configured in the UE. 2 < _Ks < 8. The _Ks CMRs correspond to the NZP-CSI-RS resource set for channel measurement. K1 and K2 are the number of CMRs in the two CMR groups, respectively. N CMR pairs are configured by higher layers by selecting from all possible pairs. N = ₁ , _Ks = ₂ are supported. Support for _Nmax = 2 is an optional UE feature. Support for _Ks,max = X is an optional UE feature. Each CMR can contain up to 32 CSI-RS ports depending on the UE capabilities. Each CMR pair is associated with one CRI value.

The bitmap in the RRC signaling indicates the N (N=1,2) CMR pairs actually used for NCJT measurement by indicating one CMR from each CMR group. The UE uses the CMRs in the two CMR groups to measure single TRP CSI for TRP1 and single TRP CSI for TRP2, and uses the N CMR pairs to measure NCJT CSI.

The UE selects one or more CSIs to report based on the mode set by csi-ReportMode. csi-ReportMode indicates one of the following two modes:

mode

1 and 2.

At least one of the following

modes

1 and 2 is supported.
[Mode 1]
The UE may be configured to report X CSIs associated to single-TRP measurement hypotheses and one CSI associated to an NCJT measurement hypothesis, where X=0,1,2. If X=2, two CSIs are associated to two different single-TRP measurement hypotheses with CMRs from different CMR groups. Support for X=1,2 is an optional UE feature for UEs supporting option 1.
[Mode 2]
The UE is configured to report one CSI associated with the best one of the measurement assumptions of NCJT and single TRP.

In Mode 1, the UE reports a total of X+1 CSIs, including X (X=0,1,2) single-TRP CSIs and one NCJT CSI. In Mode 2, the UE reports one best CSI (one CSI) from all the single-TRP CSIs and one NCJT CSI.

Up to two single-TRP CSIs and one NCJT CSI can be reported within one CSI report (mode 1 with X=2). The NCJT CSI contains one CRI, two RIs (with one joint RI index), two PMIs, two LIs, and one CQI (up to 4 layers). The single-TRP CSI is the same as the existing CSI and contains one CRI, one RI/PMI/LI, and one or two CQIs (up to 8 layers, one CQI per CW).

New mapping orders (tables) of multiple fields within one CSI report are defined for some of the following cases:
Mapping order of Wideband CSI for Mode 1 with X=0. Wideband CSI is supported only for Mode 1 with X=0, i.e., NCJT CSI.
CSI Part 1 mapping order for

modes

1 and 2.
CSI Part 2 wideband mapping order for

modes

1 and 2.
CSI Part 2 subband mapping order for

modes

1 and 2.

(CJT)
In Rel. 18, it is considered to support CJT with up to four TRPs. Data from four TRPs may be coherently precoded and transmitted to the UE on the same time-frequency resource. For example, the same precoding matrix may be used considering the channels from four TRPs. Coherent may mean that there is a certain relationship between the phases of multiple received signals. With four TRP joint precoding, the signal quality may be improved and there may be no interference in between the four TRPs. Data may only experience interference outside the four TRPs.

In the ideal case (where the four TRPs are collocated), a joint estimation of the aggregated channel matrix H can be performed and a joint precoding matrix V can be fed back. However, the large-scale path losses of the four paths can be significantly different. The joint precoding matrix V based on a constant module codebook is not accurate. In this case, the feedback per TRP and the inter-TRP coefficients can be aligned with the current NR type-2 codebook.

For a CJT of up to four TRPs in FR1, the selection of the four TRPs may be semi-static. Therefore, the selection and configuration of the four CMRs (four CSI-RS resources) for channel measurement may also be semi-static. Dynamic indication of the four TRPs from a list of CSI-RS resources is also possible, but unlikely.

The path losses from the four TRPs to the UE are different, so it is difficult to simply report one aggregated CSI that represents the joint channel matrix.

Considering fallback behavior to NCJT (i.e., single TRP), per-TRP CSI (i.e., single TRP CSI like NCJT CSI in Rel. 17) is also possible.

(CJT CSI)
Assuming ideal backhaul, synchronization, and the same number of antenna ports across multiple TRPs, CSI acquisition for coherent joint transmission (CJT) for FR1 and up to four TRPs is considered. For CJT multi-TRP for FDD, an improvement of the Rel. 16/17 type-2 codebook is considered.

The following are being considered as CSI extensions for CJT:
- CMR and IMR for measurement of up to four TRPs.
Per-TRP CSI with inter-TRP CSI feedback for x-TRP CJT.
Inter-TRP CSI: Novel feedback and codebook for inter-TRP phase matrix/inter-TRP amplitude matrix/inter-TRP matrix (including both amplitude and phase).
- Additional reportable x-TRP CJT CQI.

The following is being considered as a multi-TRP CJT CSI:
Setting restrictions on CMR/CSI for each TRP.
Inter-TRP CSI/PMI (e.g. inter-TRP phase with/without inter-TRP amplitude).
[Option 1] In addition to the Rel. 16/17 Type 2 codebook, an independent codebook and feedback.
[Option 2] W ₂ of CSI/PMI between TRPs conveyed with/within W _k ^∼ W _f,k ^H. Common/different FD basis for multiple TRPs.

The following is being considered as a multi-panel Type 2 CSI for multi-TRP CJT:
- Extension of Type 2 codebook and Type 2 PS codebook to multi-panel in Rel. 16/17.
New antenna configuration for Type 2 multi-panel codebook.

_W1 (SD basis)/ _Wf (FD basis) for each TRP may be the same or different. _Wk (NZC) for each TRP may be different. _W1 / _Wf / _Wk for each TRP may be selected jointly or individually. Different scenarios with different options for the design of _W1 / _Wf / _Wk are preferred. _Wφ may be reported as an individual content or within _Wk . These used policies relate to deployment scenarios (e.g., intra-site multi-TRP or inter-site multi-TRP).

For example, a precoding matrix for a 4-TRP CJT CSI (codebook) may be represented by W ₁ /W _f /W _k for each TRP. W ₁ for each TRP may be the same, different, jointly selected, or individually selected. W _k for each TRP may be different, jointly selected, or individually selected. W _f for each TRP may be the same, different, jointly selected, or individually selected.

In the (Rel.18) Type 2 codebook (codebook structure) for CJT multi-TRP (mTRP), at least one of the following modes (codebook modes) may be supported:

[Mode 1]
SD/FD basis selection per TRP/TRP group. It allows independent FD basis selection across N TRPs/TRP groups. For example, the codebook structure is given by: where N is the number of TRPs or TRP groups.

[Mode 2]
SD basis selection per TRP/TRP group (port group or resource) and joint/common FD basis selection (across N TRPs/TRP groups). For example, the codebook structure is given by: where N is the number of TRPs or TRP groups.

In these two modes, detailed designs such as parameter combination, basis selection, TRP (group) selection, reference amplitude, and _W2 quantization scheme may be shared.

(problem)
The setting of the maximum number of NZCs in _W2 and the setting of M for the number of FD basis vectors in _Wf have been considered. However, the setting of the number of SD basis vectors and the selection of SD basis vectors by the UE are not clear. If these considerations are not sufficient, there is a risk of a decrease in communication throughput/communication quality.

The inventors therefore came up with a method for setting/determining/reporting on CJT CSI.

The following describes in detail the embodiments of the present disclosure with reference to the drawings. Each of the following embodiments (e.g., each case) may be used alone, or at least two of them may be combined and applied.

In this disclosure, "A/B" and "at least one of A and B" may be interpreted as interchangeable. Also, in this disclosure, "A/B/C" may mean "at least one of A, B, and C."

In this disclosure, terms such as activate, deactivate, indicate, select, configure, update, and determine may be interpreted as interchangeable. In this disclosure, terms such as support, control, can be controlled, operate, and can operate may be interpreted as interchangeable.

In this disclosure, Radio Resource Control (RRC), RRC parameters, RRC messages, higher layer parameters, information elements (IEs), settings, etc. may be interchangeable. In this disclosure, Medium Access Control (MAC Control Element (CE)), update commands, activation/deactivation commands, etc. may be interchangeable.

In the present disclosure, higher layer signaling may be, for example, Radio Resource Control (RRC) signaling, Medium Access Control (MAC) signaling, broadcast information, or any combination thereof.

In the present disclosure, the MAC signaling may use, for example, a MAC Control Element (MAC CE), a MAC Protocol Data Unit (PDU), etc. The broadcast information may be, for example, a Master Information Block (MIB), a System Information Block (SIB), Remaining Minimum System Information (RMSI), Other System Information (OSI), etc.

In the present disclosure, the physical layer signaling may be, for example, Downlink Control Information (DCI), Uplink Control Information (UCI), etc.

In this disclosure, the terms index, identifier (ID), indicator, resource ID, etc. may be interchangeable. In this disclosure, the terms sequence, list, set, group, cluster, subset, etc. may be interchangeable.

In this disclosure, a panel, a panel group, a beam, a beam group, a precoder, an Uplink (UL) transmitting entity, a Transmission/Reception Point (TRP), a base station, a Spatial Relation Information (SRI), a spatial relation, an SRS Resource Indicator (SRI), a Control Resource Set (CONTROLLER RESOLUTION SET (CORESET)), a Physical Downlink Shared Channel (PDSCH), a Codeword (CW), a Transport Block (TB), a Reference Signal (RS), an antenna port (e.g., a DeModulation Reference Signal (DMRS)) port), an antenna port Group (e.g., DMRS port group), group (e.g., spatial relationship group, Code Division Multiplexing (CDM) group, reference signal group, CORESET group, Physical Uplink Control Channel (PUCCH) group, PUCCH resource group), resource (e.g., reference signal resource, SRS resource), resource set (e.g., reference signal resource set), CORESET pool, downlink Transmission Configuration Indication state (TCI state) (DL TCI state), uplink TCI state (UL TCI state), unified TCI state, common TCI state, quasi-co-location (QCL), QCL assumption, etc. may be read as interchangeable.

In this disclosure, "having the ability to..." may be read interchangeably as "supporting/reporting the ability to..."

In this disclosure, panel, base station (gNB) panel, TRP, transmission point, TCI state, reference signal, network (NW), base station, and gNB may be interpreted as interchangeable.

In this disclosure, beam, SD beam, SD basis, SD basis vector, and SD 2D-DFT vector may be interchanged. In this disclosure, L, 2L, number of SD beams, number of beams, and number of SD 2D-DFT vectors may be interchanged.

In the present disclosure, FD basis, FD basis vector, FD DFT basis, DFT basis, f _i , FD beam, FD vector, FD DFT basis vector, and DFT basis vector may be interpreted as interchangeable.

In the present disclosure, coefficients, LC coefficients, coupling coefficients, subband complex LC coefficients, coupling coefficient matrix, amplitude and phase, amplitude coefficients and phase coefficients may be interchangeable. In the present disclosure, NZC, non-zero coefficients, non-zero LC coefficients, non-zero amplitude coefficients, complex coefficients may be interchangeable.

In this disclosure, co-phasing, phase matching, phase compensation, phase adjustment, phase difference, and phase relationship may be interchangeable. In this disclosure, co-amplitude, amplitude compensation, amplitude adjustment, amplitude ratio, and amplitude relationship may be interchangeable. In this disclosure, difference, ratio, and relative value may be interchangeable.

In this disclosure, layer k and layer l may be interpreted as interchangeable.

In this disclosure, size, length, and number may be interpreted interchangeably.

(Wireless communication method)
In each embodiment, the TRP, CMR, NZP-CSI-RS resource, and CRI may be interchangeable. In each embodiment, the group/set of the TRP, the group/set of the CMR, the group/set of the NZP-CSI-RS resource, and the group/set of the CRI may be interchangeable.

In each embodiment, X TRP, X-TRP, X panels, and Ng panels may be read as interchangeable. In each embodiment, CJT using X TRP, CJT using X panels, and X-TRP CJT may be read as interchangeable.

In each embodiment, the reference CSI, the CSI for the reference TRP, and the first reported CSI may be read as interchangeable. In each embodiment, the reference TRP, the CSI corresponding to the reference CSI, the TRP corresponding to the first reported CSI, and the CSI-RS resource/CMR/CMR group/CSI-RS resource set corresponding to the first reported CSI may be read as interchangeable. In each embodiment, the TRP, CSI-RS resource, CMR, CMR group, and CSI-RS resource set may be read as interchangeable.

In each embodiment, multi-TRP, multi-panel, intra-site multi-TRP, and inter-site multi-TRP may be interpreted as interchangeable.

In each embodiment, inter-TRP, inter-panel, inter-TRP difference, and inter-TRP comparison may be interpreted as interchangeable.

In each embodiment, inter-TRP CSI, inter-TRP CJT CSI, inter-panel CSI, CSI of another TRP relative to the CSI of the reference TRP, and CSI of another TRP relative to the CSI of the reference panel may be read as interchangeable. In each embodiment, per-TRP CSI and per-panel CSI may be read as interchangeable.

In each embodiment, the inter-TRP phase index and the inter-TRP phasing index may be interchanged. In each embodiment, the inter-TRP index and the inter-TRP coefficient index may be interchanged. In each embodiment, the inter-TRP phase matrix and the inter-TRP phasing matrix may be interchanged. In each embodiment, the inter-TRP matrix and the inter-TRP coefficient matrix may be interchanged. In each embodiment, the inter-TRP phase codebook and the inter-TRP phasing codebook may be interchanged. In each embodiment, the inter-TRP codebook and the inter-TRP coefficient codebook may be interchanged.

In each embodiment, the CSI report/content may be applied to subband reports or wideband reports.

In the example of CSI in the diagram of each embodiment, the CSI for X TRPs may include the CSI of the 1st TRP to the CSI of the Xth TRP. The CSI of the i-th TRP in the diagram of each embodiment indicates the number/location of NZCs by a matrix with 2L _i rows (SD beams) and M _i columns (FD basis). _{M i} may be a value M common to the X TRPs or may be an individual value for each TRP.

In each embodiment, codebook parameter settings, parameter combinations, parameters, parameters related to the number of SD basis vectors, one or more parameters related to the number of SD basis vectors for multiple transmission points, LL, LL _i for TRP#i, LL common to multiple TRPs, LL spanning multiple TRPs, and multiple parameters LL _i corresponding to multiple TRP#i (i = 1, 2, ...) may be interpreted as interchangeable.

In the Rel. 16 (enhanced) type-2 codebook, the values of L, β, and _pv are determined by the upper layer parameter paramCombination-r16 (codebook parameter setting). Figure 5 shows an example of parameter combinations for the Rel. 16 type-2 codebook. In the Rel. 17 (further enhanced) type-2 port selection codebook, the values of α, M, and β are determined by the upper layer parameter paramCombination-r17 (codebook parameter setting). Figure 6 shows an example of parameter combinations for the Rel. 17 type-2 port selection codebook.

In codebook extension for CJT, L and α may be represented by (or replaced by) new parameters (e.g., LL).

<Embodiment #1>
This embodiment relates to a setting regarding the number of SD basis vectors. The number of SD basis vectors may be set by a parameter in paramCombination (e.g., paramCombination-rX, where X may be 18 or more). For example, the parameter may be LL or other parameters. The setting of the number of SD basis vectors may follow at least one of the following options/variations:

Option 1
To set a different number of SD basis vectors for each TRP/TRP group, either of the following options 1a and 1b are used.

[Option 1a]
A separate paramCombination is set for each TRP/TRP group. Different values of the parameter combination (paramCombination) may be set for each TRP/TRP group.

[Option 1b]
A separate LL is set for each TRP/TRP group. A different value of LL may be set for each TRP/TRP group. Parameters other than LL in paramCombination may be values for each TRP, may be values common to multiple TRPs, may be values for each TRP group, or may be values common to multiple TRP groups.

Option 2
To set the same number of SD basis vectors for all TRPs/TRP groups, either of the following options 2a and 2b is used.

[Option 2a]
A common paramCombination is set for all TRPs/TRP groups.

[Option 2b]
A common LL is set for all TRPs/TRP groups. For example, a common LL may be set for TRPs #1/#2/#3/#4. In the paramCombination, parameters other than the LL may be values for each TRP, may be values common to multiple TRPs, may be values for each TRP group, or may be values common to multiple TRP groups.

Option 3
Via paramCombination or LL, the total number of SD basis vectors for all TRPs/TRP groups is set.

Option 3 may be combined with option 1/2 if the number of SD basis vectors configured in option 1/2 is the maximum number of SD basis vectors rather than the actual number of SD basis vectors in the report. For example, when the UE determines the actual number of SD basis vectors per TRP, the UE may consider the value configured by option 1/2 to be the maximum number limit per TRP/TRP group.

"variation"
For example, different options may be set/used for different codebook modes.

According to this embodiment, the UE can appropriately configure the number of SD basis vectors.

<Embodiment #2>
This embodiment relates to the selection of SD basis vectors by the UE. In this embodiment, the number to be set may be indicated by the setting for the number of SD basis vectors in embodiment #1. The UE may follow at least one of the following options/variations:

Option 1
The UE follows a configured number LL _i for selecting and reporting SD basis vectors for each TRP#i.

This option may be applied to option 1/2 of embodiment #1. For example, if _LL1 =4, _LL2 =2, _LL3 =1, and _LL4 =1, the UE may report four SD basis vectors for TRP#1, two SD basis vectors for TRP#2, one SD basis vector for TRP#3, and one SD basis vector for TRP#4.

This option may require the following extensions to option 3 of embodiment #1.
[Extended]
The UE needs to determine the number of SD basis vectors selected for each TRP/TRP group. The UE may further report the number of SD basis vectors selected for each TRP/TRP group, or may report the association between each SD basis vector and the ID of one TRP/TRP group. For example, if LL=6 (total number of SD basis vectors for all TRPs), the UE may report the number of SD basis vectors for

TRP#

1, 2 for

TRP#

2, 1 for

TRP#

3, and 1 for TRP#4.

Option 2
The configured number is the maximum number of SD basis vectors LL, and the UE may select/report up to LL SD basis vectors. The UE may need to determine the number of SD basis vectors selected per TRP/TRP group. The UE may further report the number of SD basis vectors selected per TRP/TRP group, or may report the total number of SD basis vectors selected and report the association between each SD basis vector and the ID of one TRP/TRP group. Such configuration (e.g., setting the maximum number of SD basis vectors) may be enabled by a new RRC parameter.

The UE may follow either option 2a or 2b below.

[Option 2a]
Even if the UE selects fewer SD basis vectors than the configured LL, the UE may ensure that at least one SD basis vector is reported for each TRP/TRP group. A new RRC parameter may be configured to enable this option. In this case, if LL _i =1 is configured for one TRP#i, the UE may not need to report the number of SD basis vectors selected for that TRP#i.

[Option 2b]
The UE may determine that there are no SD basis vectors reported for a certain TRP/TRP group (the number of reported SD basis vectors is zero). New RRC parameters may be configured to enable this option.

FIG. 7 shows an example of a combination of embodiment #1 and embodiment #2 for four TRPs #1, #2, #3, and #4. LL _i is the number of SD basis vectors configured for TRP #i. LL _i,rep is the number of SD basis vectors reported for TRP #i. LL is the total number of SD basis vectors configured for all TRPs. LL _rep is the total number of SD basis vectors reported for all TRPs. For a combination of option 1/2 of embodiment #1 and option 2a of embodiment #2, if LL ₁ =4, LL ₂ =2, LL ₃ =1, and LL ₄ =1, the UE may report LL _1,rep =2, LL _2,rep =2, LL _3,rep =1, and LL _4,rep =1. For the combination of option 1/2 of embodiment #1 and option 2b of embodiment #2, if LL ₁ =4, LL ₂ =2, LL ₃ =1, LL ₄ =1, the UE may report LL _1,rep =2, LL _2,rep =2, LL _3,rep =0, LL _4,rep =0. For the combination of option 3 of embodiment #1 and option 2a of embodiment #2, if LL=6, the number of SD basis vectors reported for each TRP is 1 or more, so LL _rep is 4 or more, which is the number of TRPs. In this case, the UE may determine LL _rep =5 and report LL _1,rep =2, LL _2,rep =1, LL _3,rep =1, LL _4,rep =1. For a combination of option 3 of embodiment #1 and option 2b of embodiment #2, when LL=6, the UE may determine LL _rep =3 and report LL _1,rep =2, LL _2,rep =1, LL _3,rep =0, and LL _4,rep =0.

"variation"
For example, different options/options may be set/used for different codebook modes.

According to this embodiment, the UE can appropriately determine/report the number of SD basis vectors.

<Problem #A1>
For β (a parameter in paramCombination configured by RRC) configured by RRC to control the maximum number of NZCs for each layer and all layers, the following two options are considered:
[NZC parameter a] Same β for all TRPs.
[NZC parameter b] β differs for each TRP.

_K0 is the maximum number of NZCs for each layer. _2K0 is the maximum number of NZCs for all layers, where _K0 = ceil( _β2LM1 ), or _K0 = ceil( _β2K1M ). 2L is the number of SD beams in the Rel. 16 extended type-2 codebook. _K1 is the number of ports selected in the Rel. 17 port selection codebook.

The maximum number of NZCs controls the upper limit of the PMI size that the UE can report. A larger _K0 has better DL performance but has a larger UCI overhead.

In addition, the introduction of the following restrictions is being considered:
Maximum number of NZCs for each layer in all X TRPs in one CSI-ReportConfig.
The maximum number of NZCs for all layers in all X TRPs in one CSI-ReportConfig.

In the bitmaps reported to indicate NZC, a bitmap per TRP is being considered.

However, details regarding NZC restrictions/reporting are unclear.

As such, there has been insufficient consideration given to the setting/decisions/reporting regarding CJT CSI.

<Embodiment #A1>
This embodiment relates to a bitmap for NZC of problem #A1.

<<Bitmap 1>>
A bitmap per TRP may be reported. In a Rel. 16 Type 2 codebook, the size of each bitmap is 2LM. In a Rel. 17 Type 2 port selection codebook, the size of each bitmap is _K1M . X individual bitmaps may be reported.

<<Bitmap 2>>
One bitmap (joint bitmap) for all TRPs (X TRPs) may be reported, and the size of the joint bitmap may be Σ _i=1 ^X 2L _i M _i or Σ _i=1 ^X K _1,i M _i .

<<Bitmap 3>>
A bitmap for each group of CMRs/TRPs may be reported. If the SD beams for each TRP are different, the number of bits in the bitmap for the Y TRPs in a group may be Σ _i=1 ^Y 2L _i M _i or Σ _i=1 ^Y K _1,i M _i . If the SD beams for each TRP in a group are the same, the number of bits in the bitmap for the Y TRPs in a group may be 2L _i M _i or K _1,i M _i .

In the example of FIG. 8, the first CMR group is associated with the CSI of the first TRP and the CSI of the second TRP. The ^same N= _Mv1 =4 FD bases are used in the CSI of the first TRP and the CSI of the second TRP. Different SD beams are used in the first TRP and the second TRP in the first CMR group. _2L1 SD beams ^are used for the first TRP, _and _2L2 SD beams are used for the second TRP. The number of bits in the bitmap for the first CMR group may ^be _2L1Mv1 ₊ _2L2Mv1 .

In the example of Fig. 9, the first CMR group is associated with the CSI of the first TRP and the CSI of the second TRP. The same N = _Mv1 = 4 FD bases are used in the first TRP and the second TRP. Within the first CMR group, the ^same ^2L1 SD beams are used in the first TRP and the second TRP. ^The number of bits in the bitmap for the first CMR group may _be ^2L1Mv1 .

The use of bitmap 1/2/3 may be specified in the specifications or may be set by the RRC IE.

According to this embodiment, the UE can properly determine/report the bitmap for NZC of CJT CSI.

<Problem #A2>
Interpretation #1 (NZC parameter 1) of "same β for all TRPs" (NZC parameter a) is that the same β is set for each TRP, and the maximum number of NZCs for each layer or for all layers is considered per TRP. For example, if β=1/2, then for each TRP, up to 50% of the number of NZCs can be reported for one layer per TRP.

Interpretation #2 of "same β for all TRPs" (NZC parameter a) may be that one configured β is applied to all TRPs to limit the total number of NZCs for all TRPs. One configured β may be applied to all TRPs regardless of the maximum number of NZCs per TRP.

The maximum number of total NZCs for each layer for all TRPs (regardless of per-TRP limits) may be considered.

The maximum total number of NZCs for all layers for all TRPs (regardless of per-TRP limits) may be considered.

In the (Rel. 16) Extended Type 2 Codebook or the (Rel. 17) Extended Type 2 Port Selection Codebook, a bitmap is used to indicate the NZC in _W2 . In that bitmap, there is at least one '1'.

In CJT CSI Rel.18 and later, considering the codebook structure of CJT CSI mentioned above, _W2 is selected jointly for multiple TRPs. In the bitmap for NZC, it is not clear whether it is allowed that no NZC is selected/reported for a certain TRP.

<Embodiment #A2>
This embodiment relates to problem #A2. The UE may follow one of several options:

Option 1
It is not allowed that no NZC is selected/reported for one TRP. At least one NZC is selected/reported per TRP. The minimum number of NZCs selected/reported for one TRP may be 1.

There MAY be at least one '1' in the bitmap indicating NZC for each TRP. The signaling may be a separate bitmap for each TRP or one bitmap combined for multiple TRPs.

Option 2
It is permitted that no NZCs are selected/reported for a TRP. The minimum number of NZCs selected/reported for a TRP may be 0.

In the example of Figures 10 and 11, the number of FD bases M _i for the four TRPs is a common value M = 4, the number of SD beams for the first TRP is 2L ₁ = 8, and the number of SD beams for the other TRPs is 2L ₂ = 2L ₃ = 2L ₄ = 4. Therefore, the number of coefficients for the first TRP on a layer is 2L ₁ * M = 32, and the number of coefficients for the other TRPs on that layer is 2L ₂ * M = 2L ₃ * M = 2L ₄ * M = 16. In this example, the number of FD bases M _i is a common value for X TRPs, but may be individual values for each TRP. β = 1/2 limits the maximum number of NZCs that will be reported for each TRP. The number of NZCs actually reported may be less than the maximum number of NZCs.

In the example of Figure 10, interpretation #1 and β=1/2 are used, and NZC is not selected/reported in the fourth TRP CSI. In the example of Figure 11, interpretation #2 and β=1/4 are used, and NZC is not selected/reported in the third TRP CSI. In option 1, at least one of the examples in Figures 10 and 11 may not be allowed. In option 2, at least one of the examples in Figures 10 and 11 may be allowed.

The special case may be allowed where all NZCs selected/reported are derived from one and the same TRP.

If no NZC is selected/reported for a TRP, the bitmap indicating the NZC for that TRP may be omitted in the report. This can reduce reporting overhead.

To ensure that the UE and the base station have a common understanding regarding which bitmaps for which TRPs are omitted, the UE/base station may follow at least one of the following options:
[Option 2-1]
In CSI Part 1 with fixed size, the actual (reported) number of NZCs for each TRP is reported. For example, if the number of NZCs for four TRPs is reported as [8,2,3,0], in CSI Part 2 with variable size, there may be no bitmap and NZC for the fourth TRP.
[Option 2-2]
In the CSI Part 1, which has a fixed size, the total number of actual (reported) NZCs for all TRPs is reported. An additional bit or bits (bitmap) may be used to indicate whether each TRP has an NZC or not. For example, if 13 is reported as the total number of NZCs, an additional bitmap 1110 may be used to indicate whether each TRP has an NZC or not. A value of '0' therein may mean that the 4th TRP does not have an NZC. Bit position i in the bitmap may correspond to the i-th TRP.

UE capabilities may be introduced that support omitting TRP-specific NZC bitmaps. For example, reporting using option 2 of the CJT CSI described above may be configured only if that option is supported and the corresponding UE capabilities are reported.

　RRC configurations showing either

option

1 or 2 of this embodiment may be supported/implemented.

The maximum number of TRPs to which bitmap omission can be applied may be limited. For example, bitmap/NAC reporting may be omitted for up to one TRP.

According to this embodiment, the UE can properly report the NZC for each TRP.

<Embodiment #A3>
This embodiment relates to option 2 of embodiment #A2. If no NZC is selected/reported for a TRP, it is not clear whether the SD basis for that TRP needs to be reported (assuming that the NW configures the UE to report CJT CSI for N TRPs).

The UE may follow one of several options:

[Option 3-1]
If no NZC is selected/reported for a TRP, the SD basis for that TRP is reported in _W1 . In this case, the UE may maintain the CJT CSI reporting of N TRPs as configured.

[Option 3-2]
If no NZC is selected/reported for a TRP, the SD basis for that TRP is omitted and not reported.

If option 2-1/2-2 of embodiment #A2 is applied and bitmap and NZC reporting for a TRP is not indicated, the UE may not report the CRI index or TRP index, and may not report the SD basis index for that TRP. In this case, the overhead of CSI reporting can be further reduced.

UE capability regarding support for omission of TRP-specific SD basis may be introduced. For example, option 3-2 may be supported and configured only if the corresponding UE capability is reported.

The UE may report CJT CSI for (N-1), (N-2), ... TRPs.

RRC configurations between options 3-1 and 3-2 may be supported.

The number of TRPs to which the omission in option 3-2 applies may be limited to a maximum. For example, the bitmap and NZC of up to one TRP may be omitted.

According to this embodiment, even if no NZC is selected/reported for a certain TRP, the UE can properly report the CJT CSI.

<Additional Information>
[Notification of information to UE]
In the above-described embodiments, any information may be notified to the UE (from a network (NW) (e.g., a base station (BS))) (in other words, any information is received from the BS by the UE) using physical layer signaling (e.g., DCI), higher layer signaling (e.g., RRC signaling, MAC CE), a specific signal/channel (e.g., PDCCH, PDSCH, reference signal), or a combination thereof.

When the above notification is performed by a MAC CE, the MAC CE may be identified by including a new Logical Channel ID (LCID) in the MAC subheader that is not specified in existing standards.

When the notification is made by a DCI, the notification may be made by a specific field of the DCI, a Radio Network Temporary Identifier (RNTI) used to scramble Cyclic Redundancy Check (CRC) bits assigned to the DCI, the format of the DCI, etc.

Furthermore, notification of any information to the UE in the above-mentioned embodiments may be performed periodically, semi-persistently, or aperiodically.

[Information notification from UE]
In the above-described embodiments, notification of any information from the UE (to the NW) (in other words, transmission/report of any information from the UE to the BS) may be performed using physical layer signaling (e.g., UCI), higher layer signaling (e.g., RRC signaling, MAC CE), a specific signal/channel (e.g., PUCCH, PUSCH, PRACH, reference signal), or a combination thereof.

If the notification is made by a MAC CE, the MAC CE may be identified by including a new LCID in the MAC subheader that is not specified in existing standards.

If the notification is made by UCI, the notification may be transmitted using PUCCH or PUSCH.

Furthermore, in the above-mentioned embodiments, notification of any information from the UE may be performed periodically, semi-persistently, or aperiodically.

[Application of each embodiment]
At least one of the above-mentioned embodiments may be applied when a specific condition is satisfied, which may be specified in a standard or may be notified to a UE/BS using higher layer signaling/physical layer signaling.

At least one of the above-described embodiments may be applied only to UEs that have reported or support a particular UE capability.

The specific UE capabilities may indicate at least one of the following:
- Support for each option/choice.
Support for a different number of SD basis vectors per TRP/TRP group and a configurable maximum number of SD basis vectors per TRP/TRP group.
- Support for the same number of SD basis vectors for multiple TRPs/TRP groups and a configurable maximum number of SD basis vectors per TRP/TRP group.
Support for the total number of SD basis vectors for all TRPs/TRP groups.
Support for a maximum number of total SD basis vectors for all TRPs/TRP groups.
Support for UE to determine the number of SD basis vectors. The number of determined/selected/reported SD basis vectors may be less than or equal to the configured number of SD basis vectors.
Support for not reporting SD basis vectors for certain TRPs/TRP groups.

Furthermore, the above-mentioned specific UE capabilities may be capabilities that are applied across all frequencies (commonly regardless of frequency), capabilities per frequency (e.g., one or a combination of a cell, band, band combination, BWP, component carrier, etc.), capabilities per frequency range (e.g., Frequency Range 1 (FR1), FR2, FR3, FR4, FR5, FR2-1, FR2-2), capabilities per subcarrier spacing (SubCarrier Spacing (SCS)), or capabilities per Feature Set (FS) or Feature Set Per Component-carrier (FSPC).

The specific UE capabilities may be capabilities that are applied across all duplexing methods (commonly regardless of the duplexing method), or may be capabilities for each duplexing method (e.g., Time Division Duplex (TDD) and Frequency Division Duplex (FDD)).

Furthermore, at least one of the above-mentioned embodiments may be applied when the UE configures/activates/triggers specific information related to the above-mentioned embodiments (or performs the operations of the above-mentioned embodiments) by higher layer signaling/physical layer signaling. For example, the specific information may be information indicating that the functions of each embodiment are enabled, any RRC parameters for a specific release (e.g., Rel. 18/19), etc.

If the UE does not support at least one of the above specific UE capabilities or the above specific information is not configured, the UE may, for example, apply Rel. 15/16 operations.

(Additional Note)
With respect to one embodiment of the present disclosure, the following invention is noted.
[Appendix 1]
a receiver configured to receive one or more parameters related to a number of spatial-domain basis vectors for a plurality of transmission points;
and a control unit that determines a number of spatial domain basis vectors to be reported for the multiple transmission points based on the setting.
[Appendix 2]
2. The terminal of claim 1, wherein the one or more parameters are a plurality of parameters respectively corresponding to the plurality of transmission points.
[Appendix 3]
3. The terminal of

claim

1 or 2, wherein the one or more parameters are parameters common to the multiple transmission points.
[Appendix 4]
4. The terminal of any of claims 1 to 3, wherein the one or more parameters relate to a total number of spatial-domain basis vectors for the multiple transmission points.

(Wireless communication system)
A configuration of a wireless communication system according to an embodiment of the present disclosure will be described below. In this wireless communication system, communication is performed using any one of the wireless communication methods according to the above embodiments of the present disclosure or a combination of these.

FIG. 12 is a diagram showing an example of a schematic configuration of a wireless communication system according to an embodiment. The wireless communication system 1 (which may simply be referred to as system 1) may be a system that realizes communication using Long Term Evolution (LTE) specified by the Third Generation Partnership Project (3GPP), 5th generation mobile communication system New Radio (5G NR), or the like.

The wireless communication system 1 may also support dual connectivity between multiple Radio Access Technologies (RATs) (Multi-RAT Dual Connectivity (MR-DC)). MR-DC may include dual connectivity between LTE (Evolved Universal Terrestrial Radio Access (E-UTRA)) and NR (E-UTRA-NR Dual Connectivity (EN-DC)), dual connectivity between NR and LTE (NR-E-UTRA Dual Connectivity (NE-DC)), etc.

In EN-DC, the LTE (E-UTRA) base station (eNB) is the master node (MN), and the NR base station (gNB) is the secondary node (SN). In NE-DC, the NR base station (gNB) is the MN, and the LTE (E-UTRA) base station (eNB) is the SN.

The wireless communication system 1 may support dual connectivity between multiple base stations within the same RAT (e.g., dual connectivity in which both the MN and SN are NR base stations (gNBs) (NR-NR Dual Connectivity (NN-DC))).

The wireless communication system 1 may include a base station 11 that forms a macrocell C1 with a relatively wide coverage, and base stations 12 (12a-12c) that are arranged within the macrocell C1 and form a small cell C2 that is narrower than the macrocell C1. A user terminal 20 may be located within at least one of the cells. The arrangement and number of each cell and user terminal 20 are not limited to the embodiment shown in the figure. Hereinafter, when there is no need to distinguish between the

base stations

11 and 12, they will be collectively referred to as base station 10.

The user terminal 20 may be connected to at least one of the multiple base stations 10. The user terminal 20 may utilize at least one of carrier aggregation (CA) using multiple component carriers (CC) and dual connectivity (DC).

Each CC may be included in at least one of a first frequency band (Frequency Range 1 (FR1)) and a second frequency band (Frequency Range 2 (FR2)). Macro cell C1 may be included in FR1, and small cell C2 may be included in FR2. For example, FR1 may be a frequency band below 6 GHz (sub-6 GHz), and FR2 may be a frequency band above 24 GHz (above-24 GHz). Note that the frequency bands and definitions of FR1 and FR2 are not limited to these, and for example, FR1 may correspond to a higher frequency band than FR2.

In addition, the user terminal 20 may communicate using at least one of Time Division Duplex (TDD) and Frequency Division Duplex (FDD) in each CC.

The multiple base stations 10 may be connected by wire (e.g., optical fiber conforming to the Common Public Radio Interface (CPRI), X2 interface, etc.) or wirelessly (e.g., NR communication). For example, when NR communication is used as a backhaul between

base stations

11 and 12, base station 11, which corresponds to the upper station, may be called an Integrated Access Backhaul (IAB) donor, and base station 12, which corresponds to a relay station, may be called an IAB node.

The base station 10 may be connected to the core network 30 directly or via another base station 10. The core network 30 may include at least one of, for example, an Evolved Packet Core (EPC), a 5G Core Network (5GCN), a Next Generation Core (NGC), etc.

The core network 30 may include network functions (Network Functions (NF)) such as, for example, a User Plane Function (UPF), an Access and Mobility management Function (AMF), a Session Management Function (SMF), a Unified Data Management (UDM), an Application Function (AF), a Data Network (DN), a Location Management Function (LMF), and Operation, Administration and Maintenance (Management) (OAM). Note that multiple functions may be provided by one network node. In addition, communication with an external network (e.g., the Internet) may be performed via the DN.

The user terminal 20 may be a terminal that supports at least one of the communication methods such as LTE, LTE-A, and 5G.

In the wireless communication system 1, a wireless access method based on Orthogonal Frequency Division Multiplexing (OFDM) may be used. For example, in at least one of the downlink (DL) and uplink (UL), Cyclic Prefix OFDM (CP-OFDM), Discrete Fourier Transform Spread OFDM (DFT-s-OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier Frequency Division Multiple Access (SC-FDMA), etc. may be used.

The radio access method may also be called a waveform. In the wireless communication system 1, other radio access methods (e.g., other single-carrier transmission methods, other multi-carrier transmission methods) may be used for the UL and DL radio access methods.

In the wireless communication system 1, a downlink shared channel (Physical Downlink Shared Channel (PDSCH)) shared by each user terminal 20, a broadcast channel (Physical Broadcast Channel (PBCH)), a downlink control channel (Physical Downlink Control Channel (PDCCH)), etc. may be used as the downlink channel.

In addition, in the wireless communication system 1, an uplink shared channel (Physical Uplink Shared Channel (PUSCH)) shared by each user terminal 20, an uplink control channel (Physical Uplink Control Channel (PUCCH)), a random access channel (Physical Random Access Channel (PRACH)), etc. may be used as an uplink channel.

User data, upper layer control information, System Information Block (SIB), etc. are transmitted via PDSCH. User data, upper layer control information, etc. may also be transmitted via PUSCH. Furthermore, Master Information Block (MIB) may also be transmitted via PBCH.

Lower layer control information may be transmitted by the PDCCH. The lower layer control information may include, for example, downlink control information (Downlink Control Information (DCI)) including scheduling information for at least one of the PDSCH and the PUSCH.

Note that the DCI for scheduling the PDSCH may be called a DL assignment or DL DCI, and the DCI for scheduling the PUSCH may be called a UL grant or UL DCI. Note that the PDSCH may be interpreted as DL data, and the PUSCH may be interpreted as UL data.

A control resource set (COntrol REsource SET (CORESET)) and a search space may be used to detect the PDCCH. The CORESET corresponds to the resources to search for DCI. The search space corresponds to the search region and search method of PDCCH candidates. One CORESET may be associated with one or multiple search spaces. The UE may monitor the CORESET associated with a search space based on the search space configuration.

A search space may correspond to PDCCH candidates corresponding to one or more aggregation levels. One or more search spaces may be referred to as a search space set. Note that the terms "search space," "search space set," "search space setting," "search space set setting," "CORESET," "CORESET setting," etc. in this disclosure may be read as interchangeable.

The PUCCH may transmit uplink control information (UCI) including at least one of channel state information (CSI), delivery confirmation information (which may be called, for example, Hybrid Automatic Repeat reQuest ACKnowledgement (HARQ-ACK), ACK/NACK, etc.), and a scheduling request (SR). The PRACH may transmit a random access preamble for establishing a connection with a cell.

Note that in this disclosure, downlink, uplink, etc. may be expressed without adding "link." Also, various channels may be expressed without adding "Physical" to the beginning.

In the wireless communication system 1, a synchronization signal (SS), a downlink reference signal (DL-RS), etc. may be transmitted. In the wireless communication system 1, as the DL-RS, a cell-specific reference signal (CRS), a channel state information reference signal (CSI-RS), a demodulation reference signal (DMRS), a positioning reference signal (PRS), a phase tracking reference signal (PTRS), etc. may be transmitted.

The synchronization signal may be, for example, at least one of a Primary Synchronization Signal (PSS) and a Secondary Synchronization Signal (SSS). A signal block including an SS (PSS, SSS) and a PBCH (and a DMRS for PBCH) may be called an SS/PBCH block, an SS Block (SSB), etc. In addition, the SS, SSB, etc. may also be called a reference signal.

In addition, in the wireless communication system 1, a measurement reference signal (Sounding Reference Signal (SRS)), a demodulation reference signal (DMRS), etc. may be transmitted as an uplink reference signal (UL-RS). Note that the DMRS may also be called a user equipment-specific reference signal (UE-specific Reference Signal).

(base station)
13 is a diagram showing an example of a configuration of a base station according to an embodiment. The base station 10 includes a control unit 110, a transceiver unit 120, a transceiver antenna 130, and a transmission line interface 140. Note that one or more of each of the control unit 110, the transceiver unit 120, the transceiver antenna 130, and the transmission line interface 140 may be provided.

Note that this example mainly shows the functional blocks of the characteristic parts of this embodiment, and the base station 10 may also be assumed to have other functional blocks necessary for wireless communication. Some of the processing of each part described below may be omitted.

The control unit 110 controls the entire base station 10. The control unit 110 can be configured from a controller, a control circuit, etc., which are described based on a common understanding in the technical field to which this disclosure pertains.

The control unit 110 may control signal generation, scheduling (e.g., resource allocation, mapping), etc. The control unit 110 may control transmission and reception using the transceiver unit 120, the transceiver antenna 130, and the transmission path interface 140, measurement, etc. The control unit 110 may generate data, control information, sequences, etc. to be transmitted as signals, and transfer them to the transceiver unit 120. The control unit 110 may perform call processing of communication channels (setting, release, etc.), status management of the base station 10, management of radio resources, etc.

The transceiver unit 120 may include a baseband unit 121, a radio frequency (RF) unit 122, and a measurement unit 123. The baseband unit 121 may include a transmission processing unit 1211 and a reception processing unit 1212. The transceiver unit 120 may be composed of a transmitter/receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transceiver circuit, etc., which are described based on a common understanding in the technical field to which the present disclosure relates.

The transceiver unit 120 may be configured as an integrated transceiver unit, or may be composed of a transmission unit and a reception unit. The transmission unit may be composed of a transmission processing unit 1211 and an RF unit 122. The reception unit may be composed of a reception processing unit 1212, an RF unit 122, and a measurement unit 123.

The transmitting/receiving antenna 130 can be configured as an antenna described based on common understanding in the technical field to which this disclosure pertains, such as an array antenna.

The transceiver 120 may transmit the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transceiver 120 may receive the above-mentioned uplink channel, uplink reference signal, etc.

The transceiver 120 may form at least one of the transmit beam and the receive beam using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), etc.

The transceiver 120 (transmission processing unit 1211) may perform Packet Data Convergence Protocol (PDCP) layer processing, Radio Link Control (RLC) layer processing (e.g., RLC retransmission control), Medium Access Control (MAC) layer processing (e.g., HARQ retransmission control), etc., on data and control information obtained from the control unit 110, and generate a bit string to be transmitted.

The transceiver 120 (transmission processor 1211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, Discrete Fourier Transform (DFT) processing (if necessary), Inverse Fast Fourier Transform (IFFT) processing, precoding, and digital-to-analog conversion on the bit string to be transmitted, and output a baseband signal.

The transceiver unit 120 (RF unit 122) may perform modulation, filtering, amplification, etc., on the baseband signal to a radio frequency band, and transmit the radio frequency band signal via the transceiver antenna 130.

On the other hand, the transceiver unit 120 (RF unit 122) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transceiver antenna 130.

The transceiver 120 (reception processing unit 1212) may apply reception processing such as analog-to-digital conversion, Fast Fourier Transform (FFT) processing, Inverse Discrete Fourier Transform (IDFT) processing (if necessary), filtering, demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal, and acquire user data, etc.

The transceiver 120 (measurement unit 123) may perform measurements on the received signal. For example, the measurement unit 123 may perform Radio Resource Management (RRM) measurements, Channel State Information (CSI) measurements, etc. based on the received signal. The measurement unit 123 may measure received power (e.g., Reference Signal Received Power (RSRP)), received quality (e.g., Reference Signal Received Quality (RSRQ), Signal to Interference plus Noise Ratio (SINR), Signal to Noise Ratio (SNR)), signal strength (e.g., Received Signal Strength Indicator (RSSI)), propagation path information (e.g., CSI), etc. The measurement results may be output to the control unit 110.

The transmission path interface 140 may transmit and receive signals (backhaul signaling) between devices included in the core network 30 (e.g., network nodes providing NF), other base stations 10, etc., and may acquire and transmit user data (user plane data), control plane data, etc. for the user terminal 20.

Note that the transmitter and receiver of the base station 10 in this disclosure may be configured with at least one of the transmitter/receiver 120, the transmitter/receiver antenna 130, and the transmission path interface 140.

The transceiver unit 120 may transmit one or more parameter settings related to the number of spatial domain basis vectors for the multiple transmission points. The control unit 110 may control the reception of reports of the spatial domain basis vectors for the multiple transmission points based on the settings.

(User terminal)
14 is a diagram showing an example of the configuration of a user terminal according to an embodiment. The user terminal 20 includes a control unit 210, a transceiver unit 220, and a transceiver antenna 230. Note that the control unit 210, the transceiver unit 220, and the transceiver antenna 230 may each include one or more.

Note that this example mainly shows the functional blocks of the characteristic parts of this embodiment, and the user terminal 20 may also be assumed to have other functional blocks necessary for wireless communication. Some of the processing of each part described below may be omitted.

The control unit 210 controls the entire user terminal 20. The control unit 210 can be configured from a controller, a control circuit, etc., which are described based on a common understanding in the technical field to which this disclosure pertains.

The control unit 210 may control signal generation, mapping, etc. The control unit 210 may control transmission and reception using the transceiver unit 220 and the transceiver antenna 230, measurement, etc. The control unit 210 may generate data, control information, sequences, etc. to be transmitted as signals, and transfer them to the transceiver unit 220.

The transceiver unit 220 may include a baseband unit 221, an RF unit 222, and a measurement unit 223. The baseband unit 221 may include a transmission processing unit 2211 and a reception processing unit 2212. The transceiver unit 220 may be composed of a transmitter/receiver, an RF circuit, a baseband circuit, a filter, a phase shifter, a measurement circuit, a transceiver circuit, etc., which are described based on a common understanding in the technical field to which the present disclosure relates.

The transceiver unit 220 may be configured as an integrated transceiver unit, or may be composed of a transmission unit and a reception unit. The transmission unit may be composed of a transmission processing unit 2211 and an RF unit 222. The reception unit may be composed of a reception processing unit 2212, an RF unit 222, and a measurement unit 223.

The transmitting/receiving antenna 230 can be configured as an antenna described based on common understanding in the technical field to which this disclosure pertains, such as an array antenna.

The transceiver 220 may receive the above-mentioned downlink channel, synchronization signal, downlink reference signal, etc. The transceiver 220 may transmit the above-mentioned uplink channel, uplink reference signal, etc.

The transceiver 220 may form at least one of the transmit beam and receive beam using digital beamforming (e.g., precoding), analog beamforming (e.g., phase rotation), etc.

The transceiver 220 (transmission processor 2211) may perform PDCP layer processing, RLC layer processing (e.g., RLC retransmission control), MAC layer processing (e.g., HARQ retransmission control), etc. on the data and control information acquired from the controller 210, and generate a bit string to be transmitted.

The transceiver 220 (transmission processor 2211) may perform transmission processing such as channel coding (which may include error correction coding), modulation, mapping, filtering, DFT processing (if necessary), IFFT processing, precoding, and digital-to-analog conversion on the bit string to be transmitted, and output a baseband signal.

Whether or not to apply DFT processing may be based on the settings of transform precoding. When transform precoding is enabled for a certain channel (e.g., PUSCH), the transceiver unit 220 (transmission processing unit 2211) may perform DFT processing as the above-mentioned transmission processing in order to transmit the channel using a DFT-s-OFDM waveform, and when transform precoding is not enabled, it is not necessary to perform DFT processing as the above-mentioned transmission processing.

The transceiver unit 220 (RF unit 222) may perform modulation, filtering, amplification, etc., on the baseband signal to a radio frequency band, and transmit the radio frequency band signal via the transceiver antenna 230.

On the other hand, the transceiver unit 220 (RF unit 222) may perform amplification, filtering, demodulation to a baseband signal, etc. on the radio frequency band signal received by the transceiver antenna 230.

The transceiver 220 (reception processor 2212) may apply reception processing such as analog-to-digital conversion, FFT processing, IDFT processing (if necessary), filtering, demapping, demodulation, decoding (which may include error correction decoding), MAC layer processing, RLC layer processing, and PDCP layer processing to the acquired baseband signal to acquire user data, etc.

The transceiver 220 (measurement unit 223) may perform measurements on the received signal. For example, the measurement unit 223 may perform RRM measurements, CSI measurements, etc. based on the received signal. The measurement unit 223 may measure received power (e.g., RSRP), received quality (e.g., RSRQ, SINR, SNR), signal strength (e.g., RSSI), propagation path information (e.g., CSI), etc. The measurement results may be output to the control unit 210.

In addition, the transmitting unit and receiving unit of the user terminal 20 in this disclosure may be configured by at least one of the transmitting/receiving unit 220 and the transmitting/receiving antenna 230.

The transceiver unit 220 may receive one or more parameter settings related to the number of spatial domain basis vectors for the multiple transmission points. The control unit 210 may determine the number of spatial domain basis vectors to be reported for the multiple transmission points based on the settings.

The one or more parameters may be a plurality of parameters corresponding to the plurality of transmission points, respectively.

The one or more parameters may be parameters common to the multiple transmission points.

The one or more parameters may relate to a total number of spatial domain basis vectors for the multiple transmission points.

(Hardware configuration)
The block diagrams used in the description of the above embodiments show functional blocks. These functional blocks (components) are realized by any combination of at least one of hardware and software. The method of realizing each functional block is not particularly limited. That is, each functional block may be realized using one device that is physically or logically coupled, or may be realized using two or more devices that are physically or logically separated and directly or indirectly connected (for example, using wires, wirelessly, etc.). The functional blocks may be realized by combining the one device or the multiple devices with software.

Here, the functions include, but are not limited to, judgement, determination, judgment, calculation, computation, processing, derivation, investigation, search, confirmation, reception, transmission, output, access, resolution, selection, election, establishment, comparison, assumption, expectation, deeming, broadcasting, notifying, communicating, forwarding, configuring, reconfiguring, allocating, mapping, and assignment. For example, a functional block (component) that performs the transmission function may be called a transmitting unit, a transmitter, and the like. In either case, as mentioned above, there are no particular limitations on the method of realization.

For example, a base station, a user terminal, etc. in one embodiment of the present disclosure may function as a computer that performs processing of the wireless communication method of the present disclosure. FIG. 15 is a diagram showing an example of the hardware configuration of a base station and a user terminal according to one embodiment. The above-mentioned base station 10 and user terminal 20 may be physically configured as a computer device including a processor 1001, a memory 1002, a storage 1003, a communication device 1004, an input device 1005, an output device 1006, a bus 1007, etc.

In addition, in this disclosure, the terms apparatus, circuit, device, section, unit, etc. may be interpreted as interchangeable. The hardware configuration of the base station 10 and the user terminal 20 may be configured to include one or more of the devices shown in the figures, or may be configured to exclude some of the devices.

For example, although only one processor 1001 is shown, there may be multiple processors. Furthermore, processing may be performed by one processor, or processing may be performed by two or more processors simultaneously, sequentially, or using other techniques. Furthermore, the processor 1001 may be implemented by one or more chips.

The functions of the base station 10 and the user terminal 20 are realized, for example, by loading specific software (programs) onto hardware such as the processor 1001 and memory 1002, causing the processor 1001 to perform calculations, control communications via the communication device 1004, and control at least one of the reading and writing of data in the memory 1002 and storage 1003.

The processor 1001, for example, runs an operating system to control the entire computer. The processor 1001 may be configured as a central processing unit (CPU) including an interface with peripheral devices, a control device, an arithmetic unit, registers, etc. For example, at least a portion of the above-mentioned control unit 110 (210), transmission/reception unit 120 (220), etc. may be realized by the processor 1001.

The processor 1001 also reads out programs (program codes), software modules, data, etc. from at least one of the storage 1003 and the communication device 1004 into the memory 1002, and executes various processes according to these. The programs used are those that cause a computer to execute at least some of the operations described in the above embodiments. For example, the control unit 110 (210) may be realized by a control program stored in the memory 1002 and running on the processor 1001, and similar implementations may be made for other functional blocks.

Memory 1002 is a computer-readable recording medium and may be composed of at least one of, for example, Read Only Memory (ROM), Erasable Programmable ROM (EPROM), Electrically EPROM (EEPROM), Random Access Memory (RAM), and other suitable storage media. Memory 1002 may also be called a register, cache, main memory, etc. Memory 1002 can store executable programs (program codes), software modules, etc. for implementing a wireless communication method according to one embodiment of the present disclosure.

Storage 1003 is a computer-readable recording medium and may be composed of at least one of a flexible disk, a floppy disk, a magneto-optical disk (e.g., a compact disk (Compact Disc ROM (CD-ROM)), a digital versatile disk, a Blu-ray disk), a removable disk, a hard disk drive, a smart card, a flash memory device (e.g., a card, a stick, a key drive), a magnetic stripe, a database, a server, or other suitable storage medium. Storage 1003 may also be referred to as an auxiliary storage device.

The communication device 1004 is hardware (transmitting/receiving device) for communicating between computers via at least one of a wired network and a wireless network, and is also called, for example, a network device, a network controller, a network card, or a communication module. The communication device 1004 may be configured to include a high-frequency switch, a duplexer, a filter, a frequency synthesizer, etc., to realize at least one of Frequency Division Duplex (FDD) and Time Division Duplex (TDD). For example, the above-mentioned transmitting/receiving unit 120 (220), transmitting/receiving antenna 130 (230), etc. may be realized by the communication device 1004. The transmitting/receiving unit 120 (220) may be implemented as a transmitting unit 120a (220a) and a receiving unit 120b (220b) that are physically or logically separated.

The input device 1005 is an input device (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, etc.) that accepts input from the outside. The output device 1006 is an output device (e.g., a display, a speaker, a Light Emitting Diode (LED) lamp, etc.) that outputs to the outside. The input device 1005 and the output device 1006 may be integrated into one structure (e.g., a touch panel).

Furthermore, each device such as the processor 1001 and memory 1002 is connected by a bus 1007 for communicating information. The bus 1007 may be configured using a single bus, or may be configured using different buses between each device.

Furthermore, the base station 10 and the user terminal 20 may be configured to include hardware such as a microprocessor, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a programmable logic device (PLD), or a field programmable gate array (FPGA), and some or all of the functional blocks may be realized using the hardware. For example, the processor 1001 may be implemented using at least one of these pieces of hardware.

(Modification)
In addition, the terms described in this disclosure and the terms necessary for understanding this disclosure may be replaced with terms having the same or similar meanings. For example, a channel, a symbol, and a signal (signal or signaling) may be read as mutually interchangeable. A signal may also be a message. A reference signal may be abbreviated as RS, and may be called a pilot, a pilot signal, or the like depending on the applied standard. A component carrier (CC) may also be called a cell, a frequency carrier, a carrier frequency, or the like.

A radio frame may be composed of one or more periods (frames) in the time domain. Each of the one or more periods (frames) constituting a radio frame may be called a subframe. Furthermore, a subframe may be composed of one or more slots in the time domain. A subframe may have a fixed time length (e.g., 1 ms) that is independent of numerology.

Here, the numerology may be a communication parameter that is applied to at least one of the transmission and reception of a signal or channel. The numerology may indicate, for example, at least one of the following: SubCarrier Spacing (SCS), bandwidth, symbol length, cyclic prefix length, Transmission Time Interval (TTI), number of symbols per TTI, radio frame configuration, a specific filtering process performed by the transceiver in the frequency domain, a specific windowing process performed by the transceiver in the time domain, etc.

A slot may consist of one or more symbols in the time domain (such as Orthogonal Frequency Division Multiplexing (OFDM) symbols, Single Carrier Frequency Division Multiple Access (SC-FDMA) symbols, etc.). A slot may also be a time unit based on numerology.

A slot may include multiple minislots. Each minislot may consist of one or multiple symbols in the time domain. A minislot may also be called a subslot. A minislot may consist of fewer symbols than a slot. A PDSCH (or PUSCH) transmitted in a time unit larger than a minislot may be called PDSCH (PUSCH) mapping type A. A PDSCH (or PUSCH) transmitted using a minislot may be called PDSCH (PUSCH) mapping type B.

A radio frame, a subframe, a slot, a minislot, and a symbol all represent time units when transmitting a signal. A different name may be used for a radio frame, a subframe, a slot, a minislot, and a symbol, respectively. Note that the time units such as a frame, a subframe, a slot, a minislot, and a symbol in this disclosure may be read as interchangeable.

For example, one subframe may be called a TTI, multiple consecutive subframes may be called a TTI, or one slot or one minislot may be called a TTI. In other words, at least one of the subframe and the TTI may be a subframe (1 ms) in existing LTE, a period shorter than 1 ms (e.g., 1-13 symbols), or a period longer than 1 ms. Note that the unit representing the TTI may be called a slot, minislot, etc., instead of a subframe.

Here, TTI refers to, for example, the smallest time unit for scheduling in wireless communication. For example, in an LTE system, a base station schedules each user terminal by allocating radio resources (such as frequency bandwidth and transmission power that can be used by each user terminal) in TTI units. Note that the definition of TTI is not limited to this.

The TTI may be a transmission time unit for a channel-encoded data packet (transport block), a code block, a code word, etc., or may be a processing unit for scheduling, link adaptation, etc. When a TTI is given, the time interval (e.g., the number of symbols) in which a transport block, a code block, a code word, etc. is actually mapped may be shorter than the TTI.

Note that when one slot or one minislot is called a TTI, one or more TTIs (i.e., one or more slots or one or more minislots) may be the minimum time unit of scheduling. In addition, the number of slots (minislots) that constitute the minimum time unit of scheduling may be controlled.

A TTI having a time length of 1 ms may be called a normal TTI (TTI in 3GPP Rel. 8-12), normal TTI, long TTI, normal subframe, normal subframe, long subframe, slot, etc. A TTI shorter than a normal TTI may be called a shortened TTI, short TTI, partial or fractional TTI, shortened subframe, short subframe, minislot, subslot, slot, etc.

Note that a long TTI (e.g., a normal TTI, a subframe, etc.) may be interpreted as a TTI having a time length of more than 1 ms, and a short TTI (e.g., a shortened TTI, etc.) may be interpreted as a TTI having a TTI length shorter than the TTI length of a long TTI and equal to or greater than 1 ms.

A resource block (RB) is a resource allocation unit in the time domain and frequency domain, and may include one or more consecutive subcarriers in the frequency domain. The number of subcarriers included in an RB may be the same regardless of numerology, and may be, for example, 12. The number of subcarriers included in an RB may be determined based on numerology.

Furthermore, an RB may include one or more symbols in the time domain and may be one slot, one minislot, one subframe, or one TTI in length. One TTI, one subframe, etc. may each be composed of one or more resource blocks.

In addition, one or more RBs may be referred to as a physical resource block (Physical RB (PRB)), a sub-carrier group (Sub-Carrier Group (SCG)), a resource element group (Resource Element Group (REG)), a PRB pair, an RB pair, etc.

Furthermore, a resource block may be composed of one or more resource elements (REs). For example, one RE may be a radio resource area of one subcarrier and one symbol.

A Bandwidth Part (BWP), which may also be referred to as a partial bandwidth, may represent a subset of contiguous common resource blocks (RBs) for a given numerology on a given carrier, where the common RBs may be identified by an index of the RB relative to a common reference point of the carrier. PRBs may be defined in a BWP and numbered within the BWP.

The BWP may include a UL BWP (BWP for UL) and a DL BWP (BWP for DL). One or more BWPs may be configured for a UE within one carrier.

At least one of the configured BWPs may be active, and the UE may not expect to transmit or receive a given signal/channel outside the active BWP. Note that "cell," "carrier," etc. in this disclosure may be read as "BWP."

Note that the above-mentioned structures of radio frames, subframes, slots, minislots, and symbols are merely examples. For example, the number of subframes included in a radio frame, the number of slots per subframe or radio frame, the number of minislots included in a slot, the number of symbols and RBs included in a slot or minislot, the number of subcarriers included in an RB, as well as the number of symbols in a TTI, the symbol length, and the cyclic prefix (CP) length can be changed in various ways.

In addition, the information, parameters, etc. described in this disclosure may be represented using absolute values, may be represented using relative values from a predetermined value, or may be represented using other corresponding information. For example, a radio resource may be indicated by a predetermined index.

The names used for parameters and the like in this disclosure are not limiting in any respect. Furthermore, the formulas and the like using these parameters may differ from those explicitly disclosed in this disclosure. The various channels (PUCCH, PDCCH, etc.) and information elements may be identified by any suitable names, and therefore the various names assigned to these various channels and information elements are not limiting in any respect.

The information, signals, etc. described in this disclosure may be represented using any of a variety of different technologies. For example, the data, instructions, commands, information, signals, bits, symbols, chips, etc. that may be referred to throughout the above description may be represented by voltages, currents, electromagnetic waves, magnetic fields or magnetic particles, optical fields or photons, or any combination thereof.

In addition, information, signals, etc. may be output from a higher layer to a lower layer and/or from a lower layer to a higher layer. Information, signals, etc. may be input/output via multiple network nodes.

Input/output information, signals, etc. may be stored in a specific location (e.g., memory) or may be managed using a management table. Input/output information, signals, etc. may be overwritten, updated, or added to. Output information, signals, etc. may be deleted. Input information, signals, etc. may be transmitted to another device.

The notification of information is not limited to the aspects/embodiments described in this disclosure, and may be performed using other methods. For example, the notification of information in this disclosure may be performed by physical layer signaling (e.g., Downlink Control Information (DCI), Uplink Control Information (UCI)), higher layer signaling (e.g., Radio Resource Control (RRC) signaling, broadcast information (Master Information Block (MIB), System Information Block (SIB)), etc.), Medium Access Control (MAC) signaling), other signals, or a combination of these.

The physical layer signaling may be called Layer 1/Layer 2 (L1/L2) control information (L1/L2 control signal), L1 control information (L1 control signal), etc. The RRC signaling may be called an RRC message, for example, an RRC Connection Setup message, an RRC Connection Reconfiguration message, etc. The MAC signaling may be notified, for example, using a MAC Control Element (CE).

Furthermore, notification of specified information (e.g., notification that "X is the case") is not limited to explicit notification, but may be implicit (e.g., by not notifying the specified information or by notifying other information).

The determination may be based on a value represented by a single bit (0 or 1), a Boolean value represented by true or false, or a comparison of numerical values (e.g., with a predetermined value).

Software shall be construed broadly to mean instructions, instruction sets, code, code segments, program code, programs, subprograms, software modules, applications, software applications, software packages, routines, subroutines, objects, executable files, threads of execution, procedures, functions, etc., whether referred to as software, firmware, middleware, microcode, hardware description language, or otherwise.

Software, instructions, information, etc. may also be transmitted and received via a transmission medium. For example, if the software is transmitted from a website, server, or other remote source using at least one of wired technologies (such as coaxial cable, fiber optic cable, twisted pair, Digital Subscriber Line (DSL)), and/or wireless technologies (such as infrared, microwave, etc.), then at least one of these wired and wireless technologies is included within the definition of a transmission medium.

As used in this disclosure, the terms "system" and "network" may be used interchangeably. "Network" may refer to the devices included in the network (e.g., base stations).

In this disclosure, terms such as "precoding," "precoder," "weight (precoding weight)," "Quasi-Co-Location (QCL)," "Transmission Configuration Indication state (TCI state)," "spatial relation," "spatial domain filter," "transmit power," "phase rotation," "antenna port," "antenna port group," "layer," "number of layers," "rank," "resource," "resource set," "resource group," "beam," "beam width," "beam angle," "antenna," "antenna element," and "panel" may be used interchangeably.

In this disclosure, terms such as "Base Station (BS)", "Radio base station", "Fixed station", "NodeB", "eNB (eNodeB)", "gNB (gNodeB)", "Access point", "Transmission Point (TP)", "Reception Point (RP)", "Transmission/Reception Point (TRP)", "Panel", "Cell", "Sector", "Cell group", "Carrier", "Component carrier", etc. may be used interchangeably. Base stations may also be referred to by terms such as macrocell, small cell, femtocell, picocell, etc.

A base station can accommodate one or more (e.g., three) cells. When a base station accommodates multiple cells, the entire coverage area of the base station can be divided into multiple smaller areas, and each smaller area can also provide communication services by a base station subsystem (e.g., a small base station for indoor use (Remote Radio Head (RRH))). The term "cell" or "sector" refers to a part or the entire coverage area of at least one of the base station and base station subsystems that provide communication services in this coverage.

In this disclosure, a base station transmitting information to a terminal may be interpreted as the base station instructing the terminal to control/operate based on the information.

In this disclosure, terms such as "Mobile Station (MS)", "user terminal", "User Equipment (UE)", and "terminal" may be used interchangeably.

A mobile station may also be referred to as a subscriber station, mobile unit, subscriber unit, wireless unit, remote unit, mobile device, wireless device, wireless communication device, remote device, mobile subscriber station, access terminal, mobile terminal, wireless terminal, remote terminal, handset, user agent, mobile client, client, or some other suitable terminology.

At least one of the base station and the mobile station may be called a transmitting device, a receiving device, a wireless communication device, etc. In addition, at least one of the base station and the mobile station may be a device mounted on a moving object, the moving object itself, etc.

The moving body in question refers to an object that can move, and the moving speed is arbitrary, and of course includes the case where the moving body is stationary. The moving body in question includes, but is not limited to, vehicles, transport vehicles, automobiles, motorcycles, bicycles, connected cars, excavators, bulldozers, wheel loaders, dump trucks, forklifts, trains, buses, handcarts, rickshaws, ships and other watercraft, airplanes, rockets, artificial satellites, drones, multicopters, quadcopters, balloons, and objects mounted on these. The moving body in question may also be a moving body that moves autonomously based on an operating command.

The moving object may be a vehicle (e.g., a car, an airplane, etc.), an unmanned moving object (e.g., a drone, an autonomous vehicle, etc.), or a robot (manned or unmanned). Note that at least one of the base station and the mobile station may also include devices that do not necessarily move during communication operations. For example, at least one of the base station and the mobile station may be an Internet of Things (IoT) device such as a sensor.

FIG. 16 is a diagram showing an example of a vehicle according to an embodiment. The vehicle 40 includes a drive unit 41, a steering unit 42, an accelerator pedal 43, a brake pedal 44, a shift lever 45, left and right front wheels 46, left and right rear wheels 47, an axle 48, an electronic control unit 49, various sensors (including a current sensor 50, a rotation speed sensor 51, an air pressure sensor 52, a vehicle speed sensor 53, an acceleration sensor 54, an accelerator pedal sensor 55, a brake pedal sensor 56, a shift lever sensor 57, and an object detection sensor 58), an information service unit 59, and a communication module 60.

The drive unit 41 is composed of at least one of an engine, a motor, and a hybrid of an engine and a motor, for example. The steering unit 42 includes at least a steering wheel (also called a handlebar), and is configured to steer at least one of the front wheels 46 and the rear wheels 47 based on the operation of the steering wheel operated by the user.

The electronic control unit 49 is composed of a microprocessor 61, memory (ROM, RAM) 62, and a communication port (e.g., an Input/Output (IO) port) 63. Signals are input to the electronic control unit 49 from various sensors 50-58 provided in the vehicle. The electronic control unit 49 may also be called an Electronic Control Unit (ECU).

Signals from the various sensors 50-58 include a current signal from a current sensor 50 that senses the motor current, a rotation speed signal of the front wheels 46/rear wheels 47 acquired by a rotation speed sensor 51, an air pressure signal of the front wheels 46/rear wheels 47 acquired by an air pressure sensor 52, a vehicle speed signal acquired by a vehicle speed sensor 53, an acceleration signal acquired by an acceleration sensor 54, a depression amount signal of the accelerator pedal 43 acquired by an accelerator pedal sensor 55, a depression amount signal of the brake pedal 44 acquired by a brake pedal sensor 56, an operation signal of the shift lever 45 acquired by a shift lever sensor 57, and a detection signal for detecting obstacles, vehicles, pedestrians, etc. acquired by an object detection sensor 58.

The information service unit 59 is composed of various devices, such as a car navigation system, audio system, speakers, displays, televisions, and radios, for providing (outputting) various information such as driving information, traffic information, and entertainment information, and one or more ECUs that control these devices. The information service unit 59 uses information acquired from external devices via the communication module 60, etc., to provide various information/services (e.g., multimedia information/multimedia services) to the occupants of the vehicle 40.

The information service unit 59 may include input devices (e.g., a keyboard, a mouse, a microphone, a switch, a button, a sensor, a touch panel, etc.) that accept input from the outside, and may also include output devices (e.g., a display, a speaker, an LED lamp, a touch panel, etc.) that perform output to the outside.

The driving assistance system unit 64 is composed of various devices that provide functions for preventing accidents and reducing the driver's driving load, such as a millimeter wave radar, a Light Detection and Ranging (LiDAR), a camera, a positioning locator (e.g., a Global Navigation Satellite System (GNSS)), map information (e.g., a High Definition (HD) map, an Autonomous Vehicle (AV) map, etc.), a gyro system (e.g., an Inertial Measurement Unit (IMU), an Inertial Navigation System (INS), etc.), an Artificial Intelligence (AI) chip, and an AI processor, and one or more ECUs that control these devices. The driving assistance system unit 64 also transmits and receives various information via the communication module 60 to realize a driving assistance function or an autonomous driving function.

The communication module 60 can communicate with the microprocessor 61 and components of the vehicle 40 via the communication port 63. For example, the communication module 60 transmits and receives data (information) via the communication port 63 between the drive unit 41, steering unit 42, accelerator pedal 43, brake pedal 44, shift lever 45, left and right front wheels 46, left and right rear wheels 47, axles 48, the microprocessor 61 and memory (ROM, RAM) 62 in the electronic control unit 49, and the various sensors 50-58 that are provided on the vehicle 40.

The communication module 60 is a communication device that can be controlled by the microprocessor 61 of the electronic control unit 49 and can communicate with an external device. For example, it transmits and receives various information to and from the external device via wireless communication. The communication module 60 may be located either inside or outside the electronic control unit 49. The external device may be, for example, the above-mentioned base station 10 or user terminal 20. The communication module 60 may also be, for example, at least one of the above-mentioned base station 10 and user terminal 20 (it may function as at least one of the base station 10 and user terminal 20).

The communication module 60 may transmit at least one of the signals from the various sensors 50-58 described above input to the electronic control unit 49, information obtained based on the signals, and information based on input from the outside (user) obtained via the information service unit 59 to an external device via wireless communication. The electronic control unit 49, the various sensors 50-58, the information service unit 59, etc. may be referred to as input units that accept input. For example, the PUSCH transmitted by the communication module 60 may include information based on the above input.

The communication module 60 receives various information (traffic information, signal information, vehicle distance information, etc.) transmitted from an external device and displays it on an information service unit 59 provided in the vehicle. The information service unit 59 may also be called an output unit that outputs information (for example, outputs information to a device such as a display or speaker based on the PDSCH (or data/information decoded from the PDSCH) received by the communication module 60).

The communication module 60 also stores various information received from external devices in memory 62 that can be used by the microprocessor 61. Based on the information stored in memory 62, the microprocessor 61 may control the drive unit 41, steering unit 42, accelerator pedal 43, brake pedal 44, shift lever 45, left and right front wheels 46, left and right rear wheels 47, axles 48, various sensors 50-58, and the like provided on the vehicle 40.

Furthermore, the base station in the present disclosure may be read as a user terminal. For example, each aspect/embodiment of the present disclosure may be applied to a configuration in which communication between a base station and a user terminal is replaced with communication between multiple user terminals (which may be called, for example, Device-to-Device (D2D), Vehicle-to-Everything (V2X), etc.). In this case, the user terminal 20 may be configured to have the functions of the base station 10 described above. Furthermore, terms such as "uplink" and "downlink" may be read as terms corresponding to terminal-to-terminal communication (for example, "sidelink"). For example, the uplink channel, downlink channel, etc. may be read as the sidelink channel.

Similarly, the user terminal in this disclosure may be interpreted as a base station. In this case, the base station 10 may be configured to have the functions of the user terminal 20 described above.

In this disclosure, operations that are described as being performed by a base station may in some cases be performed by its upper node. In a network that includes one or more network nodes having base stations, it is clear that various operations performed for communication with terminals may be performed by the base station, one or more network nodes other than the base station (such as, but not limited to, a Mobility Management Entity (MME) or a Serving-Gateway (S-GW)), or a combination of these.

Each aspect/embodiment described in this disclosure may be used alone, in combination, or switched between depending on the implementation. In addition, the processing procedures, sequences, flow charts, etc. of each aspect/embodiment described in this disclosure may be rearranged as long as there is no inconsistency. For example, the methods described in this disclosure present elements of various steps using an exemplary order, and are not limited to the particular order presented.

Each aspect/embodiment described in this disclosure includes Long Term Evolution (LTE), LTE-Advanced (LTE-A), LTE-Beyond (LTE-B), SUPER 3G, IMT-Advanced, 4th generation mobile communication system (4G), 5th generation mobile communication system (5G), 6th generation mobile communication system (6G), xth generation mobile communication system (xG (x is, for example, an integer or decimal)), Future Radio Access (FRA), New-Radio The present invention may be applied to systems that use Access Technology (RAT), New Radio (NR), New radio access (NX), Future generation radio access (FX), Global System for Mobile communications (GSM (registered trademark)), CDMA2000, Ultra Mobile Broadband (UMB), IEEE 802.11 (Wi-Fi (registered trademark)), IEEE 802.16 (WiMAX (registered trademark)), IEEE 802.20, Ultra-WideBand (UWB), Bluetooth (registered trademark), and other appropriate wireless communication methods, as well as next-generation systems that are expanded, modified, created, or defined based on these. In addition, multiple systems may be combined (for example, a combination of LTE or LTE-A and 5G, etc.).

As used in this disclosure, the phrase "based on" does not mean "based only on," unless expressly stated otherwise. In other words, the phrase "based on" means both "based only on" and "based at least on."

Any reference to elements using designations such as "first," "second," etc., used in this disclosure does not generally limit the quantity or order of those elements. These designations may be used in this disclosure as a convenient method of distinguishing between two or more elements. Thus, a reference to a first and second element does not imply that only two elements may be employed or that the first element must precede the second element in some way.

The term "determining" as used in this disclosure may encompass a wide variety of actions. For example, "determining" may be considered to be judging, calculating, computing, processing, deriving, investigating, looking up, search, inquiry (e.g., looking in a table, database, or other data structure), ascertaining, etc.

"Determining" may also be considered to mean "determining" receiving (e.g., receiving information), transmitting (e.g., sending information), input, output, accessing (e.g., accessing data in a memory), etc.

"Judgment" may also be considered to mean "deciding" to resolve, select, choose, establish, compare, etc. In other words, "judgment" may also be considered to mean "deciding" to take some kind of action.

In addition, "judgment (decision)" may be interpreted as "assuming," "expecting," "considering," etc.

The "maximum transmit power" referred to in this disclosure may mean the maximum value of transmit power, may mean the nominal UE maximum transmit power, or may mean the rated UE maximum transmit power.

As used in this disclosure, the terms "connected" and "coupled," or any variation thereof, refer to any direct or indirect connection or coupling between two or more elements, and may include the presence of one or more intermediate elements between two elements that are "connected" or "coupled" to each other. The coupling or connection between the elements may be physical, logical, or a combination thereof. For example, "connected" may be read as "accessed."

In this disclosure, when two elements are connected, they may be considered to be "connected" or "coupled" to one another using one or more wires, cables, printed electrical connections, and the like, as well as using electromagnetic energy having wavelengths in the radio frequency range, microwave range, light (both visible and invisible) range, and the like, as some non-limiting and non-exhaustive examples.

In this disclosure, the term "A and B are different" may mean "A and B are different from each other." The term may also mean "A and B are each different from C." Terms such as "separate" and "combined" may also be interpreted in the same way as "different."

When the terms "include," "including," and variations thereof are used in this disclosure, these terms are intended to be inclusive, similar to the term "comprising." Additionally, the term "or," as used in this disclosure, is not intended to be an exclusive or.

In this disclosure, where articles have been added through translation, such as a, an, and the in English, this disclosure may include that the nouns following these articles are plural.

In this disclosure, terms such as "less than", "less than", "greater than", "more than", "equal to", etc. may be read as interchangeable. In addition, in this disclosure, terms meaning "good", "bad", "big", "small", "high", "low", "fast", "slow", "wide", "narrow", etc. may be read as interchangeable, not limited to positive, comparative and superlative. In addition, in this disclosure, terms meaning "good", "bad", "big", "small", "high", "low", "fast", "slow", "wide", "narrow", etc. may be read as interchangeable, not limited to positive, comparative and superlative, as expressions with "ith" (i is any integer) (for example, "best" may be read as "ith best").

In this disclosure, the terms "of," "for," "regarding," "related to," "associated with," etc. may be read interchangeably.

　The invention disclosed herein has been described in detail above, but it is clear to those skilled in the art that the invention disclosed herein is not limited to the embodiments described herein. The invention disclosed herein can be implemented in modified and altered forms without departing from the spirit and scope of the invention as defined by the claims. Therefore, the description of the disclosure is intended as an illustrative example and does not impose any limiting meaning on the invention disclosed herein.

Claims

a receiver configured to receive one or more parameters related to a number of spatial-domain basis vectors for a plurality of transmission points;
and a control unit that determines a number of spatial domain basis vectors to be reported for the multiple transmission points based on the setting.
The terminal according to claim 1, wherein the one or more parameters are a plurality of parameters corresponding to the plurality of transmission points, respectively.
The terminal according to claim 1, wherein the one or more parameters are parameters common to the multiple transmission points.
The terminal of claim 1, wherein the one or more parameters relate to a total number of spatial domain basis vectors for the multiple transmission points.
receiving one or more parameter settings related to a number of spatial domain basis vectors for a plurality of transmission points;
and determining a number of spatial domain basis vectors to be reported for the plurality of transmission points based on the configuration.
a transmitter for transmitting one or more parameter settings related to a number of spatial domain basis vectors for a plurality of transmission points;
A base station comprising: a controller that controls reception of reports of spatial domain basis vectors for the plurality of transmission points based on the configuration.