Method and apparatus for transmitting and receiving channel state information in a wireless communication system

Abstract

A method and apparatus for transmitting and receiving channel state information in a wireless communication system are disclosed. According to an embodiment of the present disclosure, a method performed by a UE may include receiving configuration information related to a CSI report from a base station, receiving CSI-RS on K CSI-RS resources from the base station (K is a natural number), and transmitting CSI to the base station, where the CSI includes PMI corresponding to a codebook index.

Description

[Technical Field]

[0001] The present disclosure relates to wireless communication systems, and more particularly to methods and apparatus for transmitting and receiving channel state information in wireless communication systems. [Background technology]

[0002] Mobile communication systems were developed to provide voice services while ensuring user activity. However, the scope of mobile communication systems has expanded beyond voice to include data services. Currently, resource shortages are occurring due to the explosive growth in traffic, and users are demanding faster services, so a more advanced mobile communication system is needed.

[0003] The requirements for next-generation mobile communication systems are to accommodate large and explosive data traffic, dramatically increase the transmission rate per user, accommodate a significantly increased number of connected devices, support very low end-to-end latency, and high energy efficiency.To achieve this, various technologies are being researched, including dual connectivity, massive multiple input multiple output (MIMO), in-band full duplex, non-orthogonal multiple access (NOMA), super wideband support, and device networking. Summary of the Invention [Problem to be solved by the invention]

[0004] A technical problem of the present disclosure is to provide a method and apparatus for transmitting and receiving channel state information.

[0005] Another technical object of the present disclosure is to provide a method and apparatus for transmitting and receiving channel state information for multiple transmission and reception points (TRPs).

[0006] Another technical object of the present disclosure is to provide a method and apparatus for transmitting and receiving channel state information including a precoding matrix indicator for coherent joint transmission (CJT) in multiple TRPs.

[0007] The technical problems to be solved by the present disclosure are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by a person having ordinary skill in the art to which the present disclosure pertains from the following description. [Means for solving the problem]

[0008] A method performed by a user equipment (UE) in a wireless communication system according to one embodiment of the present disclosure may include receiving configuration information associated with a channel state information (CSI) report from a base station, receiving CSI-reference signal (CSI-RS) on K CSI-RS resources from the base station (K is a natural number), and transmitting CSI to the base station, the CSI including a precoding matrix indicator (PMI) corresponding to a codebook index. the configuration information includes i) first information for one or more first parameters and ii) second information for a combination of a second parameter and a third parameter, the precoding matrix indicated by the PMI is determined from a plurality of vectors, the number of the plurality of vectors is determined based on the one or more first parameters and the second parameter, the codebook index includes an amplitude coefficient indicator indicating one or more amplitude coefficients and a phase coefficient indicator indicating one or more phase coefficients, an upper bound on the total number of non-zero coefficients in the one or more amplitude coefficients and the one or more phase coefficients is determined based on the one or more first parameters, the second parameter, and the third parameter, and configurable combinations of i) the one or more first parameters and ii) the combination of the second parameter and the third parameter may be determined individually depending on the number of the K CSI-RS resources.

[0009] A method performed by a base station in a wireless communication system according to a further aspect of the present disclosure may include (may comprise; may configure; may establish; may configure; may encompass; may contain; may contain) the following steps: transmitting configuration information associated with a channel state information (CSI) report to a user equipment (UE); transmitting CSI-RS to the UE on K CSI-reference signal (CSI-RS) resources (K is a natural number); and receiving CSI from the UE, the CSI including a precoding matrix indicator (PMI) corresponding to a codebook index. the configuration information includes i) first information for one or more first parameters and ii) second information for a combination of a second parameter and a third parameter, the precoding matrix indicated by the PMI is determined from a plurality of vectors, the number of the plurality of vectors is determined based on the one or more first parameters and the second parameter, the codebook index includes an amplitude coefficient indicator indicating one or more amplitude coefficients and a phase coefficient indicator indicating one or more phase coefficients, an upper bound on the total number of non-zero coefficients in the one or more amplitude coefficients and the one or more phase coefficients is determined based on the one or more first parameters, the second parameter, and the third parameter, and configurable combinations of i) the one or more first parameters and ii) the combination of the second parameter and the third parameter may be determined individually depending on the number of the K CSI-RS resources. [Effects of the Invention]

[0010] According to an embodiment of the present disclosure, flexible operation can be supported when performing transmission and reception operations (e.g., CJT operations) in multiple TRPs.

[0011] According to the embodiments of the present disclosure, when performing transmission / reception operations (for example, CJT operations) in multiple TRPs, signaling for configuration information is simplified, thereby reducing signaling overhead.

[0012] The effects obtained from the present disclosure are not limited to the effects mentioned above, and other effects not mentioned will be clearly understood by those having ordinary skill in the art to which the present disclosure pertains from the following description. [Brief explanation of the drawings]

[0013] The accompanying drawings, which are included as part of the detailed description to aid in understanding the present disclosure, provide examples of the present disclosure and, together with the detailed description, explain the technical features of the present disclosure. [Figure 1] FIG. 1 is a diagram illustrating the structure of a wireless communication system to which the present disclosure can be applied. [Figure 2] FIG. 1 is a diagram illustrating a frame structure in a wireless communication system to which the present disclosure can be applied. [Figure 3] FIG. 1 illustrates a resource grid in a wireless communication system to which the present disclosure can be applied. [Figure 4] FIG. 1 is a diagram illustrating a physical resource block in a wireless communication system to which the present disclosure can be applied. [Figure 5] FIG. 1 illustrates a slot structure in a wireless communication system to which the present disclosure can be applied. [Figure 6] 1 is a diagram illustrating physical channels used in a wireless communication system to which the present disclosure can be applied and a general signal transmission / reception method using the physical channels. [Figure 7] 1 is a diagram illustrating an example of an antenna configuration in a wireless communication system to which the present disclosure can be applied. [Figure 8] FIG. 1 illustrates an example of an aggregated channel for CJT in a wireless communication system to which the present disclosure can be applied. [Figure 9] FIG. 1 illustrates an example of an eType II codebook for CJT in a wireless communication system to which the present disclosure can be applied. [Figure 10] A diagram illustrating a signaling procedure between a network and a UE for a channel state information transmission and reception method according to one embodiment of the present disclosure. [Figure 11] FIG. 10 is a diagram illustrating the operation of a UE with respect to a channel state information transmission and reception method according to one embodiment of the present disclosure. [Figure 12] 10 is a diagram illustrating the operation of a base station for a channel state information transmission and reception method according to an embodiment of the present disclosure. [Figure 13] FIG. 1 is a block diagram illustrating a wireless communication device according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0014] Preferred embodiments of the present disclosure will be described in detail below with reference to the accompanying drawings. The detailed description disclosed below together with the accompanying drawings is intended to describe exemplary embodiments of the present disclosure and is not intended to represent the only embodiments in which the present disclosure can be implemented. The detailed description below includes specific details to provide a complete understanding of the present disclosure. However, it will be understood by those skilled in the art that the present disclosure can be implemented without such specific details.

[0015] In some cases, in order to avoid obscuring the concepts of the present disclosure, known structures and devices may be omitted or shown in block diagram form, focusing on the core functions of each structure and device.

[0016] In this disclosure, when a component is "coupled," "coupled," or "connected" to another component, this may include a direct connection as well as an indirect connection where there is another component between them. Also, in this disclosure, the terms "comprise" or "have" specify the presence of stated features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof.

[0017] In this disclosure, terms such as "first" and "second" are used only to distinguish one component from another, not to limit the components, and do not limit the order or importance of the components unless otherwise specified. Therefore, within the scope of this disclosure, a first component in one embodiment may be referred to as a second component in another embodiment, and similarly, a second component in one embodiment may be referred to as a first component in another embodiment.

[0018] The terms used in this disclosure are for the purpose of describing particular embodiments and are not intended to limit the scope of the claims. As used in the description of the embodiments and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms unless the context clearly dictates otherwise. The term "and / or" used in this disclosure means that one of the associated listed items may be used, or that any and all possible combinations of two or more of them may be used. Also, in this disclosure, " / " between words has the same meaning as "and / or" unless otherwise specified.

[0019] The present disclosure is described with respect to a wireless communication network or a wireless communication system, and operations performed in a wireless communication network may be performed in the process in which a device (e.g., a base station) that manages the wireless communication network controls the network and transmits or receives signals, or in the process in which a terminal coupled to the wireless network transmits or receives signals to or from the network or between terminals.

[0020] In this disclosure, transmitting or receiving a channel includes transmitting or receiving information or signals on the channel. For example, transmitting a control channel means transmitting control information or signals on the control channel. Similarly, transmitting a data channel means transmitting data information or signals on the data channel.

[0021] Hereinafter, downlink (DL) refers to communication from a base station to a terminal, and uplink (UL) refers to communication from a terminal to a base station. In the downlink, a transmitter may be part of the base station, and a receiver may be part of the terminal. In the uplink, a transmitter may be part of the terminal, and a receiver may be part of the base station. The base station may be expressed as a first communication device, and the terminal may be expressed as a second communication device. A base station (BS) may be replaced with terms such as a fixed station, Node B, evolved-Node B (eNB), Next Generation Node B (gNB), base transceiver system (BTS), access point (AP), network (5G network), artificial intelligence (AI) system / module, road side unit (RSU), robot, unmanned aerial vehicle (UAV), augmented reality (AR) device, virtual reality (VR) device, etc. Furthermore, a terminal may be fixed or mobile, and may be replaced with terms such as UE (User Equipment), MS (Mobile Station), UT (user terminal), MSS (Mobile Subscriber Station), SS (Subscriber Station), AMS (Advanced Mobile Station), WT (Wireless terminal), MTC (Machine-Type Communication) device, M2M (Machine-to-Machine) device, D2D (Device-to-Device) device, vehicle, RSU (road side unit), robot, AI (Artificial Intelligence) module, drone (UAV: Unmanned Aerial Vehicle), AR (Augmented Reality) device, VR (Virtual Reality) device, etc.

[0022] The following technologies may be used for various wireless access systems, such as CDMA, FDMA, TDMA, OFDMA, SC-FDMA, etc. CDMA may be implemented by radio technologies such as Universal Terrestrial Radio Access (UTRA) and CDMA2000. TDMA may be implemented by radio technologies such as Global System for Mobile communications (GSM), General Packet Radio Service (GPRS), and Enhanced Data Rates for GSM Evolution (EDGE). OFDMA may be implemented by radio technologies such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, Evolved UTRA (E-UTRA), etc. UTRA is part of the Universal Mobile Telecommunications System (UMTS). 3GPP (3rd Generation Partnership Project: registered trademark) LTE (Long Term Evolution) is a part of E-UMTS (Evolved UMTS) that uses E-UTRA, and LTE-A (Advanced) / LTE-A pro is an evolved version of 3GPP LTE. 3GPP NR (New Radio or New Radio Access Technology) is an evolved version of 3GPP LTE / LTE-A / LTE-A pro.

[0023] For clarity, the following description will be based on a 3GPP communication system (e.g., LTE-A, NR), but the technical concept of the present disclosure is not limited thereto. LTE refers to technology from 3GPP Technical Specification (TS) 36.xxx Release 8 onward. Specifically, LTE technology from 3GPP TS 36.xxx Release 10 onward is called LTE-A, and LTE technology from 3GPP TS 36.xxx Release 13 onward is called LTE-A pro. 3GPP NR refers to technology from TS 38.xxx Release 15 onward. LTE / NR may be referred to as a 3GPP system. "xxx" refers to the standard document detail number. LTE / NR may be referred to as a 3GPP system. For background technology, terms, abbreviations, etc. used in the description of the present disclosure, please refer to the matters described in standard documents published before the present disclosure. For example, the following documents may be referenced:

[0024] In 3GPP LTE, reference can be made to TS 36.211 (Physical channels and modulation), TS 36.212 (Multiplexing and channel coding), TS 36.213 (Physical layer procedures), TS 36.300 (General description), and TS 36.331 (Radio resource control).

[0025] For 3GPP NR, reference can be made to TS 38.211 (Physical Channels and Modulation), TS 38.212 (Multiplexing and Channel Coding), TS 38.213 (Physical Layer Procedures for Control), TS 38.214 (Physical Layer Procedures for Data), TS 38.300 (General Description of NR and NG-RAN (New Generation-Radio Access Network)), and TS 38.331 (Radio Resource Control Protocol Standard).

[0026] The terminology abbreviations that may be used in this disclosure are defined as follows:

[0027] - BM: Beam management

[0028] - CQI: Channel Quality Indicator

[0029] - CRI: Channel state information-reference signal resource indicator

[0030] - CSI: Channel State Information

[0031] - CSI-IM: Channel state information-interference measurement

[0032] - CSI-RS: Channel state information-reference signal

[0033] - DMRS: Demodulation Reference Signal

[0034] - FDM: Frequency Division Multiplexing

[0035] - FFT: Fast Fourier transform

[0036] - IFDMA: Interleaved frequency division multiple access

[0037] - IFFT: Inverse fast Fourier transform

[0038] - L1-RSRP: Layer 1 reference signal received power

[0039] - L1-RSRQ: Layer 1 reference signal received quality

[0040] - MAC: Medium Access Control

[0041] - NZP: Non-zero power

[0042] - OFDM: Orthogonal frequency division multiplexing

[0043] - PDCCH: Physical downlink control channel

[0044] - PDSCH: Physical downlink shared channel

[0045] - PMI: Precoding matrix indicator

[0046] - RE: resource element

[0047] - RI: Rank indicator

[0048] - RRC: Radio resource control

[0049] - RSSI: received signal strength indicator

[0050] - Rx: Reception

[0051] - QCL: quasi co-location

[0052] - SINR: Signal to interference and noise ratio

[0053] - SSB (or SS / PBCH block): Synchronization signal block (including primary synchronization signal (PSS), secondary synchronization signal (SSS), and physical broadcast channel (PBCH))

[0054] - TDM: time division multiplexing

[0055] - TRP: transmission and reception point

[0056] - TRS: Tracking reference signal

[0057] - Tx: transmission

[0058] - UE: User equipment

[0059] - ZP: Zero power

[0060] System in general

[0061] As more communication devices require greater communication capacity, there is a growing need for improved mobile broadband communication compared to existing radio access technologies (RATs). Massive Machine Type Communications (MTC), which connects multiple devices and objects to provide a variety of services anytime, anywhere, is also one of the key issues being considered for next-generation communications. In addition, communication system designs that take into account reliability- and latency-sensitive services / terminals are also being discussed. Thus, the introduction of next-generation RATs that take into account technologies such as enhanced mobile broadband communication (eMBB), massive MTC (MMTC), and ultra-reliable and low latency communication (URLLC) is being discussed. For convenience, these technologies will be referred to as NR in this disclosure. NR is an example of a 5G RAT.

[0062] New RAT systems, including NR, use an OFDM transmission scheme or a similar transmission scheme. The new RAT system may follow OFDM parameters different from those of LTE. Alternatively, the new RAT system may follow the existing LTE / LTE-A numerology but support a larger system bandwidth (e.g., 100 MHz). Alternatively, one cell may support multiple numerologies. That is, terminals operating with different numerologies may coexist within one cell.

[0063] A numerology corresponds to one subcarrier spacing in the frequency domain. Different numerologies can be defined by scaling the reference subcarrier spacing by an integer N.

[0064] FIG. 1 illustrates the structure of a wireless communication system to which the present disclosure can be applied.

[0065] Referring to FIG. 1, the NG-RAN is composed of gNBs that provide the NG-RA (NG-Radio Access) user plane (i.e., new access stratum (AS) sublayer / Packet Data Convergence Protocol (PDCP) / Radio Link Control (RLC) / MAC / PHY) and control plane (RRC) protocol termination for the UE. The gNBs are interconnected via an Xn interface. The gNBs are also connected to an NGC (New Generation Core) via an NG interface. More specifically, the gNBs are connected to an AMF (Access and Mobility Management Function) via an N2 interface and to a UPF (User Plane Function) via an N3 interface.

[0066] FIG. 2 illustrates a frame structure in a wireless communication system to which the present disclosure can be applied.

[0067] An NR system can support multiple numerologies. Here, a numerology may be defined by subcarrier spacing and cyclic prefix (CP) overhead. In this case, multiple subcarrier spacings may be derived by scaling the base (reference) subcarrier spacing by an integer N (or μ). Furthermore, even if it is assumed that very low subcarrier spacings are not used at very high carrier frequencies, the numerology used may be selected independently of the frequency band. Furthermore, an NR system may support various frame structures based on multiple numerologies.

[0068] The following describes OFDM numerologies and frame structures that can be considered in an NR system. A number of OFDM numerologies supported in an NR system may be defined as shown in Table 1 below.

[0069] [Table 1]

[0070] NR supports multiple numerologies (or subcarrier spacing (SCS)) to support various 5G services. For example, a 15 kHz SCS supports wide areas in traditional cellular bands, a 30 kHz / 60 kHz SCS supports dense urban areas, lower latency, and wider carrier bandwidths, and a 60 kHz or higher SCS supports bandwidths greater than 24.25 GHz to overcome phase noise.

[0071] The NR frequency band is defined as two types of frequency ranges (FR1 and FR2). FR1 and FR2 may be configured as shown in Table 2 below. FR2 may also refer to millimeter wave (mmW).

[0072] [Table 2]

[0073] In relation to the frame structure in an NR system, the size of the various fields in the time domain is T c =1 / (Δf max N f ) where Δf max =480 103 Hz and N f = 4096. Downlink and uplink transmission is T f =1 / (Δf max N f / 100)·T c The radio frame is organized into radio frames each having a duration of T = 10 ms. sf =(Δf max N f / 1000)·T c In this case, there may be one set of frames for the uplink and one set of frames for the downlink. In addition, transmission from a terminal in uplink frame number i begins T TA =(N TA +N TA,offset )T c For a subcarrier spacing configuration μ, a slot is allocated within a subframe. s μ ∈{0,...,N slot subframe,μ -1}, and n s,f μ ∈{0,...,N slot frame,μ -1}. One slot is numbered N symb slot It consists of N consecutive OFDM symbols, symb slot is determined by the CP. s μ The start of OFDM symbol n s μ N symb slotNot all terminals can transmit and receive at the same time, which means that not all OFDM symbols in a downlink slot or uplink slot can be used.

[0074] Table 3 shows the number of OFDM symbols per slot (N symb slot ), the number of slots per radio frame (N slot frame,μ ), the number of slots per subframe (N slot subframe,μ ) and Table 4 shows the number of OFDM symbols per slot, the number of slots per radio frame, and the number of slots per subframe in the extended CP.

[0075] [Table 3]

[0076] [Table 4]

[0077] Figure 2 shows an example where μ = 2 (SCS is 60 kHz), and one subframe can include four slots as shown in Table 3. One subframe = {1, 2, 4} slots shown in Figure 2 is an example, and the number of slots that can be included in one subframe is defined as shown in Table 3 or Table 4. Also, a mini-slot can include 2, 4, or 7 symbols, or more or fewer symbols.

[0078] In relation to physical resources in an NR system, antenna ports, resource grids, resource elements, resource blocks, carrier parts, etc. may be considered. The physical resources that can be considered in an NR system will be specifically described below.

[0079] First, with respect to antenna ports, the antenna port is defined so that the channel on which symbols on the antenna port are carried can be inferred from the channel on which other symbols on the same antenna port are carried. If the large-scale properties of the channel on which symbols on one antenna port are carried can be inferred from the channel on which symbols on the other antenna port are carried, the two antenna ports are said to have a QC / QCL (quasi co-located or quasi co-location) relationship. Here, the large-scale properties include one or more of delay spread, Doppler spread, frequency shift, average received power, and received timing.

[0080] FIG. 3 illustrates a resource grid in a wireless communication system to which the present disclosure can be applied.

[0081] JPEG2025539715000006.jpg95161

[0082] JPEG2025539715000007.jpg65166

[0083] Point A serves as a common reference point for the resource block grid and is obtained as follows:

[0084] - offsetToPointA for the primary cell (PCell) downlink indicates the frequency offset between point A and the lowest subcarrier of the lowest resource block that overlaps with the SS / PBCH block used by the terminal for initial cell selection. It is expressed in resource block units assuming a 15 kHz subcarrier spacing for FR1 and a 60 kHz subcarrier spacing for FR2.

[0085] - absoluteFrequencyPointA indicates the frequency-location of point A expressed as in ARFCN (absolute radio-frequency channel number).

[0086] Common resource blocks are numbered from 0 upwards in the frequency domain for a subcarrier spacing setting μ. The center of subcarrier 0 of common resource block 0 for a subcarrier spacing setting μ coincides with 'point A'. In the frequency domain, common resource block number n CRB μ The relationship between the resource elements (k, l) for the subcarrier spacing setting μ is given by the following Equation 1.

[0087]

number

[0088] In Equation 1, k is defined relative to point A such that k=0 corresponds to the subcarrier centered at point A. The physical resource blocks are numbered from 0 to N within a bandwidth part (BWP). BWP,i size,μ Physical resource block n in BWP i is numbered from -1 to i. PRB and common resource block n CRB The relationship between is given by Equation 2 below.

[0089]

number

[0090] N BWP,i start,μ is the common resource block where the BWP starts relative to common resource block 0.

[0091] Fig. 4 illustrates a physical resource block in a wireless communication system to which the present disclosure can be applied, and Fig. 5 illustrates a slot structure in a wireless communication system to which the present disclosure can be applied.

[0092] 4 and 5, a slot includes multiple symbols in the time domain. For example, in the general CP, one slot includes seven symbols, while in the extended CP, one slot includes six symbols.

[0093] A carrier wave includes multiple subcarriers in the frequency domain. A resource block (RB) is defined as multiple (e.g., 12) consecutive subcarriers in the frequency domain. A bandwidth part (BWP) is defined as multiple consecutive (physical) resource blocks in the frequency domain, and may correspond to one numerology (e.g., SCS, CP length, etc.). A carrier wave can include up to N (e.g., 5) BWPs. Data communication is performed using activated BWPs, and only one BWP may be activated for one terminal. Each element in the resource grid is called a resource element (RE), and one complex symbol may be mapped to it.

[0094] The NR system may support up to 400 MHz per component carrier (CC). If a terminal operating on such a wideband CC keeps the radio frequency (RF) chip for the entire CC on at all times, battery consumption may increase. Alternatively, considering various application cases (e.g., eMBB, URLLC, MMTc, V2X, etc.) operating within a single wideband CC, different numerologies (e.g., subcarrier spacing, etc.) may be supported for each frequency band within the CC. Alternatively, each terminal may have different capabilities for maximum bandwidth. In consideration of this, a base station may instruct a terminal to operate only with a portion of the bandwidth of a wideband CC, rather than the entire bandwidth. For convenience, this portion of bandwidth is defined as a bandwidth part (BWP). A BWP may consist of contiguous RBs on the frequency axis and may correspond to one numerology (e.g., subcarrier spacing, CP length, slot / minislot duration).

[0095] Meanwhile, a base station can configure multiple BWPs within one CC configured for a terminal. For example, a BWP occupying a relatively small frequency region can be configured in a PDCCH monitoring slot, and the PDSCH indicated by the PDCCH can be scheduled on a larger BWP. Alternatively, when UEs are concentrated in a specific BWP, other BWPs can be configured for some terminals for load balancing. Alternatively, considering frequency domain inter-cell interference cancellation between neighboring cells, some spectrum from the entire bandwidth can be excluded and both BWPs can be configured within the same slot. That is, a base station can configure at least one DL / UL BWP for a terminal associated with a wideband CC. The base station can activate at least one DL / UL BWP configured at a specific time (by L1 signaling, MAC Control Element (CE), RRC signaling, etc.). In addition, the base station can instruct switching to another configured DL / UL BWP (by L1 signaling, MAC CE, RRC signaling, etc.). Alternatively, the base station may switch to a predetermined DL / UL BWP when a timer value expires on a timer basis. In this case, the activated DL / UL BWP is defined as an active DL / UL BWP. However, in situations where the UE is performing an initial access procedure or before an RRC connection is set up, the UE may not be able to receive the configuration for the DL / UL BWP. Therefore, the DL / UL BWP assumed by the UE in such a situation is defined as the initially active DL / UL BWP.

[0096] FIG. 6 illustrates physical channels used in a wireless communication system to which the present disclosure can be applied, and a general signal transmission / reception method using the physical channels.

[0097] In a wireless communication system, a terminal receives information from a base station through a downlink and transmits information to the base station through an uplink. Information exchanged between the base station and the terminal includes data and various control information, and various physical channels exist depending on the type / purpose of the information exchanged.

[0098] When a terminal is powered on or newly enters a cell, it performs an initial cell search, such as synchronizing with a base station (S601). To do this, the terminal receives a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) from the base station to synchronize with the base station and acquire information such as a cell identifier (ID). The terminal then receives a physical broadcast channel (PBCH) from the base station to acquire broadcast information within the cell. Meanwhile, the terminal can receive a downlink reference signal (DL RS) during the initial cell search phase to check the downlink channel status.

[0099] After completing the initial cell search, the terminal receives a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH) based on the information carried on the PDCCH, thereby obtaining more specific system information (S602).

[0100] Meanwhile, when the terminal first connects to the base station or when there are no radio resources for signal transmission, the terminal can perform a random access procedure (RACH) with the base station (steps S603 to S606). To this end, the terminal transmits a specific sequence as a preamble on a physical random access channel (PRACH) (steps S603 and S605) and can receive a response message to the preamble on a PDCCH and a corresponding PDSCH (steps S604 and S606). In the case of a contention-based RACH, a contention resolution procedure can also be performed.

[0101] After performing the above-described procedures, the UE can then perform PDCCH / PDSCH reception (S607) and Physical Uplink Shared Channel (PUSCH) / Physical Uplink Control Channel (PUCCH) transmission (S608) as a general uplink / downlink signal transmission procedure. In particular, the UE receives downlink control information (DCI) through the PDCCH. Here, DCI includes control information such as resource allocation information for the UE, and its format varies depending on its purpose.

[0102] Meanwhile, control information that a terminal transmits to a base station on the uplink or that the terminal receives from a base station includes downlink / uplink ACK / NACK (Acknowledgement / Non-Acknowledgement) signals, CQI (Channel Quality Indicator), PMI (Precoding Matrix Indicator), RI (Rank Indicator), etc. In a 3GPP LTE system, a terminal can transmit the above-mentioned control information such as CQI / PMI / RI on a PUSCH and / or a PUCCH.

[0103] Table 5 shows an example of a DCI format in an NR system.

[0104] [Table 6]

[0105] Referring to Table 5, DCI formats 0_0, 0_1, and 0_2 may include resource information related to PUSCH scheduling (e.g., UL / SUL (Supplementary UL), frequency resource allocation, time resource allocation, frequency hopping, etc.), transport block (TB) related information (e.g., MCS (Modulation Coding and Scheme), NDI (New Data Indicator), RV (Redundancy Version), etc.), HARQ (Hybrid-Automatic Repeat and request) related information (e.g., process number, DAI (Downlink Assignment Index), PDSCH-HARQ feedback timing, etc.), multiple antenna related information (e.g., DMRS sequence initialization information, antenna port, CSI request, etc.), and power control information (e.g., PUSCH power control, etc.), and the control information included in each DCI format may be predefined.

[0106] DCI format 0_0 is used for PUSCH scheduling in one cell. Information included in DCI format 0_0 is CRC (cyclic redundancy check) scrambled using a C-RNTI (Cell Radio Network Temporary Identifier), a CS-RNTI (Configured Scheduling RNTI), or an MCS-C-RNTI (Modulation Coding Scheme Cell RNTI) before being transmitted.

[0107] DCI format 0_1 ​​is used to indicate scheduling of one or more PUSCHs in one cell or downlink feedback information of configured grants (CGs) to a terminal. The information included in DCI format 0_1 ​​is CRC-scrambled using C-RNTI, CS-RNTI, SP-CSI-RNTI (Semi-Persistent CSI RNTI), or MCS-C-RNTI and then transmitted.

[0108] DCI format 0_2 is used for PUSCH scheduling in one cell. Information included in DCI format 0_2 is CRC scrambled using C-RNTI, CS-RNTI, SP-CSI-RNTI, or MCS-C-RNTI and then transmitted.

[0109] Next, DCI formats 1_0, 1_1, and 1_2 may include resource information related to PDSCH scheduling (e.g., frequency resource allocation, time resource allocation, VRB (virtual resource block)-PRB (physical resource block) mapping, etc.), transmission block (TB) related information (e.g., MCS, NDI, RV, etc.), HARQ related information (e.g., process number, DAI, PDSCH-HARQ feedback timing, etc.), multiple antenna related information (e.g., antenna port, TCI (transmission configuration indicator), SRS (sounding reference signal) request, etc.), and PUCCH related information (e.g., PUCCH power control, PUCCH resource indicator, etc.), and the control information included in each DCI format may be pre-defined.

[0110] DCI format 1_0 is used for scheduling PDSCH in one DL cell. Information included in DCI format 1_0 is CRC scrambled using C-RNTI, CS-RNTI, or MCS-C-RNTI and then transmitted.

[0111] DCI format 1_1 is used for scheduling PDSCH in one cell. Information included in DCI format 1_1 is CRC scrambled using C-RNTI, CS-RNTI, or MCS-C-RNTI and then transmitted.

[0112] DCI format 1_2 is used for scheduling PDSCH in one cell. Information included in DCI format 1_2 is CRC scrambled using C-RNTI, CS-RNTI, or MCS-C-RNTI and then transmitted.

[0113] CSI-related operations In a New Radio (NR) system, channel state information-reference signal (CSI-RS) is used for time and / or frequency tracking, CSI computation, L1 (layer 1)-RSRP (reference signal received power) computation, and mobility. Here, CSI computation is related to CSI acquisition, and L1-RSRP computation is related to beam management (BM).

[0114] CSI (Channel State Information) is a general term for information that can indicate the quality of a wireless channel (also referred to as a link) formed between a terminal and an antenna port.

[0115] To perform one of the above-described uses of the CSI-RS, a terminal (e.g., user equipment, UE) receives configuration information related to CSI from a base station (e.g., general Node B, gNB) via radio resource control (RRC) signaling.

[0116] The CSI-related configuration information may include at least one of CSI-IM (interference management) resource-related information, CSI measurement configuration-related information, CSI resource configuration-related information, CSI-RS resource-related information, or CSI report configuration-related information.

[0117] i) The CSI-IM resource-related information may include CSI-IM resource information, CSI-IM resource set information, etc. A CSI-IM resource set is identified by a CSI-IM resource set identifier, and one resource set includes at least one CSI-IM resource. Each CSI-IM resource is identified by a CSI-IM resource ID.

[0118] ii) The CSI resource configuration related information may be expressed as a CSI-ResourceConfig IE. The CSI resource configuration related information defines a group including at least one of an NZP (non-zero power) CSI-RS resource set, a CSI-IM resource set, or a CSI-SSB resource set. That is, the CSI resource configuration related information includes a CSI-RS resource set list, which may include at least one of an NZP CSI-RS resource set list, a CSI-IM resource set list, or a CSI-SSB resource set list. A CSI-RS resource set is identified by a CSI-RS resource set ID, and one resource set includes at least one CSI-RS resource. Each CSI-RS resource is identified by a CSI-RS resource ID.

[0119] A parameter indicating the use of CSI-RS for each NZP CSI-RS resource set (for example, a BM-related "repetition" parameter, a tracking-related "trs-Info" parameter) may be set.

[0120] iii) The CSI reporting configuration related information includes a reportConfigType parameter indicating a time domain behavior and a reportQuantity parameter indicating a CSI-related quantity to report, which may be periodic, aperiodic, or semi-persistent.

[0121] The terminal measures the CSI based on configuration information associated with the CSI.

[0122] The CSI measurement may include (1) a process of receiving a CSI-RS from a terminal, and (2) a process of computing CSI using the received CSI-RS, which will be described in detail later.

[0123] For the CSI-RS, the RE (resource element) mapping of the CSI-RS resource is configured in the time and frequency domains by a higher layer parameter, CSI-RS-ResourceMapping.

[0124] The terminal reports the measured CSI to the base station.

[0125] Here, if the quantity of CSI-ReportConfig is set to 'none (or No report)', the terminal may omit the report. However, even if the quantity is set to 'none (or No report)', the terminal may report to the base station. The quantity is set to 'none' when aperiodic TRS is triggered or repetition is set. Here, the terminal may omit the report only when repetition is set to 'ON'.

[0126] CSI measurement The NR system supports more flexible and dynamic CSI measurement and reporting, where the CSI measurement may include a procedure of receiving a CSI-RS and performing computation on the received CSI-RS to acquire CSI.

[0127] Aperiodic / semi-persistent / periodic channel measurement (CM) and interference measurement (IM) are supported as time domain behaviors of CSI measurement and reporting. A 4-port NZP CSI-RS RE pattern is used for CSI-IM configuration.

[0128] NR's CSI-IM-based IMR has a similar design to LTE's CSI-IM, and is configured independently of the ZP CSI-RS resources for PDSCH rate matching. In NZP CSI-RS-based IMR, each port emulates an interference layer with (preferred channel and) precoded NZP CSI-RS. This is for intra-cell interference measurement in the multi-user case, and primarily targets MU interference.

[0129] The base station transmits the precoded NZP CSI-RS to the terminal on each port of the configured NZP CSI-RS-based IMR.

[0130] The terminal measures interference assuming a channel / interference layer for each port in the resource set.

[0131] In the absence of any PMI and RI feedback for a channel, multiple resources are configured in a set, and the base station or network indicates a subset of NZP CSI-RS resources for channel / interference measurement in the DCI.

[0132] Resource settings and resource setting configurations will now be described in more detail.

[0133] resource setting Each CSI resource setting "CSI-ResourceConfig" includes a configuration for S≧1 CSI resource sets (given by the higher layer parameter csi-RS-ResourceSetList). The CSI resource setting corresponds to CSI-RS-resourcesetlist, where S represents the number of configured CSI-RS resource sets. Here, the configuration for S≧1 CSI resource sets includes each CSI resource set including CSI-RS resources (configured as NZP CSI-RS or CSI-IM) and SS / PBCH block (SSB) resources used for L1-RSRP calculation.

[0134] Each CSI resource setting is located in a DL BWP (bandwidth part) identified by a higher layer parameter bwp-id, and all CSI resource settings linked to a CSI reporting setting have the same DL BWP.

[0135] The time domain behavior of the CSI-RS resources within the CSI resource setting contained in the CSI-ResourceConfig IE is indicated by the higher layer parameter resourceType and may be configured as aperiodic, periodic, or semi-persistent. For periodic and semi-persistent CSI resource settings, the number of configured CSI-RS resource sets (S) is limited to '1'. For periodic and semi-persistent CSI resource settings, the configured periodicity and slot offset are given by the numerology of the associated DL BWP, as given by bwp-id.

[0136] When a UE is configured with multiple CSI-ResourceConfigs that include the same NZP CSI-RS resource ID, the same time domain behavior is configured for the CSI-ResourceConfigs.

[0137] When a UE is configured with multiple CSI-ResourceConfigs that include the same CSI-IM resource ID, the same time domain behavior is configured for the CSI-ResourceConfigs.

[0138] Next, one or more CSI resource settings for channel measurement (CM) and interference measurement (IM) are configured by higher layer signaling.

[0139] - CSI-IM resources for interference measurements.

[0140] - NZP CSI-RS resources for interference measurements.

[0141] - NZP CSI-RS resources for channel measurements.

[0142] That is, the channel measurement resource (CMR) may be the NZP CSI-RS for CSI acquisition, and the interference measurement resource (IMR) may be the CSI-IM and the NZP CSI-RS for IM.

[0143] Here, CSI-IM (or ZP CSI-RS for IM) is mainly used for inter-cell interference measurement.

[0144] And the NZP CSI-RS for IM is mainly used for measuring intra-cell interference from multiple users (multi-users).

[0145] The UE may assume that the CSI-RS resource for channel measurement and the CSI-IM / NZP CSI-RS resource for interference measurement configured for one CSI report are 'QCL-TypeD' for each resource.

[0146] resource setting configuration As mentioned above, a resource setting can refer to a resource set list.

[0147] For aperiodic CSI, each trigger state configured using the higher layer parameter CSI-AperiodicTriggerState is associated with one or more CSI-ReportConfigs, where each CSI-ReportConfig is linked to a periodic, semi-persistent, or aperiodic resource setting.

[0148] One reporting setting may be linked to up to three resource settings.

[0149] - If one resource setting is configured, the resource setting (given by the higher layer parameter resourcesForChannelMeasurement) is for channel measurements for L1-RSRP calculation.

[0150] - When two resource settings are configured, the first resource setting (given by the higher layer parameter resourcesForChannelMeasurement) is for channel measurement, and the second resource setting (given by csi-IM-ResourcesForInterference or nzp-CSI-RS-ResourcesForInterference) is for interference measurements performed on CSI-IM or NZP CSI-RS.

[0151] - When three resource settings are configured, the first resource setting (given by resourcesForChannelMeasurement) is for channel measurement, the second resource setting (given by csi-IM-ResourcesForInterference) is for CSI-IM-based interference measurement, and the third resource setting (given by nzp-CSI-RS-ResourcesForInterference) is for NZP CSI-RS-based interference measurement.

[0152] For semi-persistent or periodic CSI, each CSI-ReportConfig is linked to a periodic or semi-persistent resource setting.

[0153] If one resource setting (given by resourcesForChannelMeasurement) is configured, the resource setting is for channel measurement for L1-RSRP calculation.

[0154] - When two resource settings are configured, the first resource setting (given by resourcesForChannelMeasurement) is for channel measurement, and the second resource setting (given by the higher layer parameter csi-IM-ResourcesForInterference) is used for interference measurement performed on CSI-IM.

[0155] CSI calculation When interference measurement is performed on CSI-IM, each CSI-RS resource for channel measurement is associated with a CSI-IM resource by resource according to the order of the CSI-RS resource and the CSI-IM resource in the corresponding resource set, and the number of CSI-RS resources for channel measurement is the same as the number of CSI-IM resources.

[0156] And, when interference measurement is performed on NZP CSI-RS, the UE does not expect one or more NZP CSI-RS resources to be configured in the resource set associated in the resource setting for channel measurement.

[0157] A terminal with the upper layer parameter nzp-CSI-RS-ResourcesForInterference configured does not expect more than 18 NZP CSI-RS ports to be configured in the NZP CSI-RS resource set.

[0158] For CSI measurement, the terminal assumes the following:

[0159] Each NZP CSI-RS port configured for interference measurement corresponds to the interference transmission layer.

[0160] - All interference transmission layers of the NZP CSI-RS port for interference measurement take into account the EPRE (energy per resource element) ratio.

[0161] - Other interfering signals on the RE of the NZP CSI-RS resource for channel measurement, the NZP CSI-RS resource for interference measurement or the CSI-IM resource for interference measurement.

[0162] CSI report The time and frequency resources that the UE can use for CSI reporting are controlled by the base station.

[0163] The channel state information (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), or an L1-RSRP.

[0164] For CQI, PMI, CRI, SSBRI, LI, RI, and L1-RSRP, the UE is configured by a higher layer with N≧1 CSI-ReportConfig reporting settings, M≧1 CSI-ResourceConfig resource settings, and one or two lists of trigger states (provided by aperiodicTriggerStateList and semiPersistentOnPUSCH-TriggerStateList). Each trigger state in the aperiodicTriggerStateList includes an associated CSI-ReportConfigs list indicating the channel and, optionally, the resource set ID for interference. Each trigger state in the semiPersistentOnPUSCH-TriggerStateList includes one associated CSI-ReportConfig.

[0165] And the time domain behavior of CSI reporting supports periodic, semi-persistent, and aperiodic.

[0166] i) Periodic CSI reporting is performed on short PUCCH and long PUCCH. The periodicity and slot offset of periodic CSI reporting may be configured by RRC, and refer to the CSI-ReportConfig IE.

[0167] ii) SP (semi-periodic) CSI reporting is performed on short PUCCH, long PUCCH, or PUSCH.

[0168] In the case of SP CSI on short / long PUCCH, the periodicity and slot offset are configured by RRC, and CSI reporting is activated / deactivated by a separate MAC CE / DCI.

[0169] When SP CSI is reported on the PUSCH, the periodicity of the SP CSI reporting is configured by RRC, but the slot offset is not configured by RRC, and the SP CSI reporting is activated / deactivated by DCI (format 0_1). A separate RNTI (SP-CSI C-RNTI) is used for the SP CSI reporting on the PUSCH.

[0170] The timing of the first CSI report follows the PUSCH time domain allocation value indicated by the DCI, and the timing of subsequent CSI reports follows the period set by the RRC.

[0171] DCI format 0_1 ​​includes a CSI request field that can activate / deactivate a specific configured SP-CSI trigger state. The SP CSI report has the same or similar activation / deactivation mechanism as that for data transmission on the SPS PUSCH.

[0172] iii) Aperiodic CSI reporting is performed on the PUSCH and is triggered by DCI. In this case, information related to triggering of aperiodic CSI reporting may be conveyed / indicated / configured in the MAC-CE.

[0173] For AP CSI with AP CSI-RS, the AP CSI-RS timing is configured by RRC, and the timing for AP CSI reporting is dynamically controlled by DCI.

[0174] NR does not apply the method of separately reporting CSI for multiple reporting instances (e.g., transmitting RI, WB PMI / CQI, SB PMI / CQI in that order) that was applied to PUCCH-based CSI reporting in LTE. Instead, NR restricts specific CSI reporting from being configured in short / long PUCCH, and defines a CSI omission rule. Furthermore, the PUSCH symbol / slot position in relation to the AP CSI reporting timing is dynamically indicated by DCI. Furthermore, the candidate slot offset is configured by RRC. For CSI reporting, the slot offset (Y) is configured separately for each reporting setting. For UL-SCH, the slot offset K2 is configured separately.

[0175] Two CSI latency classes (low latency class and high latency class) are defined in terms of CSI computation complexity. Low latency CSI refers to WB CSI including up to a 4-port Type-I codebook or up to a 4-port non-PMI feedback CSI. High latency CSI refers to CSI other than low latency CSI. For a normal UE, (Z, Z') are defined in units of OFDM symbols. Here, Z represents the minimum CSI processing time from receiving aperiodic CSI triggering DCI until CSI reporting. Also, Z' represents the minimum CSI processing time from receiving CSI-RS for channel / interference until CSI reporting.

[0176] Furthermore, the terminal reports the number of CSIs that can be calculated simultaneously.

[0177] The following describes the CSI reporting configuration defined in TS 38.214.

[0178] The UE calculates the CSI parameters assuming the following dependencies between the CSI parameters:

[0179] - LI is calculated conditional on the reported CQI, PMI, RI, and CRI.

[0180] - CQI is calculated subject to the reported PMI, RI, and CRI.

[0181] - PMI is calculated subject to the reported RI and CRI.

[0182] - RI is calculated conditional on the reported CRI.

[0183] The reporting configuration for CSI can be aperiodic (using PUSCH), periodic (using PUCCH), or semi-persistent (using PUCCH and DCI-activated PUSCH), and the CSI-RS resource can be periodic, semi-persistent, or aperiodic. Table 6 below illustrates supported combinations between CSI reporting configurations and CSI resource configurations and how CSI reporting is triggered for each CSI resource configuration. Periodic CSI-RS is configured by higher layers. Semi-persistent CSI-RS is activated or deactivated according to the operations defined in TS 38.214. Aperiodic CSI-RS is configured and triggered / activated according to the operations defined in TS 38.214.

[0184] Table 6 illustrates the triggering / activation of CSI reporting for possible CSI-RS configurations.

[0185] [Table 7]

[0186] The following provides examples of information related to activation / deactivation / triggering by MAC-CE in connection with semi-persistent / aperiodic CSI reporting defined in TS 38.321.

[0187] - Activation / deactivation of semi-persistent CSI-RS / CSI-IM resource sets

[0188] The network can activate and / or deactivate the configured semi-persistent CSI-RS / CSI-IM resource set of the serving cell by transmitting a SP (semi-persistent) CSI-RS / CSI-IM resource set activation / deactivation MAC CE. The configured semi-persistent CSI-RS / CSI-IM resource set is deactivated at the time of configuration, initially, and after handover.

[0189] The MAC entity is i) When the MAC entity receives an SP CSI-RS / CSI-IM resource set activation / deactivation MAC CE on the serving cell, ii) Indicate information related to SP CSI-RS / CSI-IM resource set activation / deactivation MAC CE to lower layers.

[0190] - Aperiodic CSI trigger state sub-selection

[0191] The network can select among the configured aperiodic CSI trigger states of the serving cell by transmitting an aperiodic CSI trigger state sub-selection MAC CE.

[0192] The MAC entity is i) When the MAC entity receives an aperiodic CSI trigger state sub-selection MAC CE on the serving cell, ii) Indicate information related to the aperiodic CSI trigger state subselection MAC CE to lower layers.

[0193] quasi-co location (QCL) Antenna ports are defined such that the channel carried by symbols on an antenna port can be inferred from the channel carried by other symbols on the same antenna port. Two antenna ports are said to be quasi-colocated (QC / QCL) if the properties of the channel carried by symbols on one antenna port can be inferred from the channel carried by symbols on the other antenna port.

[0194] Here, the channel characteristics include one or more of delay spread, Doppler spread, frequency / Doppler shift, average received power, received timing / average delay, and spatial RX parameters, where the spatial RX parameters refer to spatial (reception) channel characteristic parameters such as the angle of arrival.

[0195] The terminal may be configured with a list of up to M TCI-State configurations in the higher layer parameter PDSCH-Config to decode the PDSCH with the detected PDCCH having DCI intended for the terminal and a given serving cell, where M depends on the UE capability.

[0196] Each TCI-State includes parameters for setting a quasi-coordinate relationship between one or two DL reference signals and a demodulation reference signal (DM-RS) port of a PDSCH.

[0197] The quasi-coordinate relationship is configured by the higher layer parameters qcl-Type1 for the first DL RS and qcl-Type2 (if configured) for the second DL RS. For two DL RSs, the QCL types are not the same, regardless of whether the references are the same DL RS or different DL RSs.

[0198] The QCL type corresponding to each DL RS is given by the higher layer parameter qcl-Type in QCL-Info and can take one of the following values:

[0199] - "QCL-TypeA": {Doppler shift, Doppler spread, mean delay, delay spread}

[0200] - "QCL-TypeB": {Doppler shift, Doppler spread}

[0201] - "QCL-TypeC": {Doppler shift, average delay}

[0202] - "QCL-TypeD": {Spatial reception parameters}

[0203] For example, if a target antenna port is a specific NZP CSI-RS, the NZP CSI-RS antenna port may be instructed / configured to be QCL-connected with a specific TRS from the perspective of QCL-Type A, and with a specific SSB from the perspective of QCL-Type D. A terminal receiving such instruction / configuration can receive the NZP CSI-RS using the Doppler and delay values ​​measured from the QCL-TypeA TRS, and can apply the receive beam used for QCL-TypeD SSB reception to the NZP CSI-RS reception.

[0204] The UE can receive an activation command via MAC CE signaling, which is used to map up to eight TCI states to codepoints in the DCI field 'Transmission Configuration Indication'.

[0205] Type-II codebook

[0206] Table 7 illustrates the Type II codebook described in 3GPP TS 38.214 in Rel-15 and Rel-16.

[0207] [Table 8]

[0208] [Table 7-2] JPEG2025539715000013.jpg209156

[0209] [Table 7-3] JPEG2025539715000014.jpg208156

[0210] [Table 7-4] JPEG2025539715000015.jpg205156

[0211] [Table 7-5] JPEG2025539715000016.jpg206156

[0212] [Table 7-6] JPEG2025539715000017.jpg207156

[0213] [Table 7-7] JPEG2025539715000018.jpg194156

[0214] [Table 7-8] JPEG2025539715000019.jpg204157

[0215] [Table 7-9] JPEG2025539715000020.jpg208157

[0216] [Table 7-10] JPEG2025539715000021.jpg208157

[0217] [Table 7-11] JPEG2025539715000022.jpg204157

[0218] [Table 7-12] JPEG2025539715000023.jpg210157

[0219] [Table 7-13] JPEG2025539715000024.jpg205156

[0220] [Table 7-14] JPEG2025539715000025.jpg210157

[0221] [Table 7-15] JPEG2025539715000026.jpg212157

[0222] [Table 7-16] JPEG2025539715000027.jpg209157

[0223] [Table 7-17] JPEG2025539715000028.jpg198156

[0224] [Table 7-18] JPEG2025539715000029.jpg119156

[0225] Multi-TRP related operations

[0226] The Coordinated Multipoint (CoMP) technique is a method for effectively controlling interference by multiple base stations exchanging (e.g., using the X2 interface) or utilizing channel information (e.g., RI / CQI / PMI / LI (layer indicator)) fed back from terminals and transmitting coordinated data to the terminal. Depending on the method used, CoMP can be categorized into joint transmission (JT), coordinated scheduling (CS), coordinated beamforming (CB), dynamic point selection (DPS), dynamic point blocking (DPB), etc.

[0227] The M-TRP transmission method, in which M TRPs transmit data to one terminal, can be broadly divided into i) eMBB M-TRP transmission, which is a method for increasing the transmission rate, and ii) URLLC M-TRP transmission, which is a method for increasing the reception success rate and reducing latency.

[0228] In terms of DCI transmission, the M-TRP transmission method can be divided into i) M-DCI (multiple DCI)-based M-TRP transmission, in which each TRP transmits an individual DCI, and ii) S-DCI (single DCI)-based M-TRP transmission, in which one TRP transmits DCI. For example, in the case of S-DCI-based M-TRP transmission, all scheduling information for data transmitted by the M TRP must be transmitted to the UE via a single DCI, and it can be used in an ideal backhaul (ideal BH) environment where dynamic coordination between two TRPs is possible.

[0229] A UE can recognize PUSCHs (or PUCCHs) scheduled by DCIs received in different control resource sets (CORESETs) (or CORESETs belonging to different CORESET groups) as PUSCHs (or PUCCHs) transmitted to different TRPs or as PDSCHs (or PDCCHs) of different TRPs. In addition, the scheme for UL transmissions (e.g., PUSCHs / PUCCHs) transmitted to different TRPs, which will be described later, can also be applied to UL transmissions (e.g., PUSCHs / PUCCHs) transmitted to different panels belonging to the same TRP.

[0230] Hereinafter, a CORESET group identifier (group ID) described / mentioned in this disclosure may refer to an index / identification information (e.g., ID) for distinguishing a CORESET for each TRP / panel. A CORESET group may be a group / union of CORESETs distinguished by an index / identification information (e.g., ID) / CORESET group ID for distinguishing a CORESET for each TRP / panel. As an example, a CORESET group ID may be specific index information defined in a CORESET configuration. In this case, a CORESET group may be set / indicated / defined by an index defined in a CORESET configuration for each CORESET. And / or a CORESET group ID may refer to an index / identification information / designator for distinguishing / identifying CORESETs set / associated with each TRP / panel. Hereinafter, the CORESET group ID described / mentioned in the present disclosure may be rephrased as a specific index / specific identification information / specific indicator for distinguishing / identifying between CORESETs set to / associated with each TRP / panel. The CORESET group ID, i.e., a specific index / specific identification information / specific indicator for distinguishing / identifying between CORESETs set to / associated with each TRP / panel, may be set / instructed to a terminal by higher layer signaling (e.g., RRC signaling), layer 2 signaling (L2 signaling, e.g., MAC-CE), layer 1 signaling (L1 signaling, e.g., DCI), etc. As an example, it may be set / instructed to perform PDCCH detection for each TRP / panel (i.e., for each TRP / panel belonging to the same CORESET group) in units of the CORESET group.And / or, it may be configured / instructed that uplink control information (e.g., CSI, HARQ-A / N (ACK / NACK), SR (scheduling request)) and / or uplink physical channel resources (e.g., PUCCH / PRACH / SRS resources) are separately managed / controlled for each TRP / panel (i.e., for each TRP / panel belonging to the same CORESET group) in the CORESET group unit. And / or, HARQ A / N (process / retransmission) for PDSCH / PUSCH, etc. scheduled for each TRP / panel (i.e., for each TRP / panel belonging to the same CORESET group) may be managed.

[0231] For example, a ControlResourceSet information element (IE), which is an upper layer parameter, is used to configure a time / frequency control resource set (CORESET). As an example, the control resource set (CORESET) may be related to detection and reception of downlink control information. The ControlResourceSet IE may include a CORESET-related ID (e.g., controlResourceSetID), a CORESET pool index (e.g., CORESETPoolIndex) for the CORESET, a time / frequency resource configuration of the CORESET, TCI information related to the CORESET, etc. As an example, a CORESET pool index (e.g., CORESETPoolIndex) may be set to 0 or 1. In the above, the CORESET group may correspond to the CORESET pool, and the CORESET group ID may correspond to the CORESET pool index (e.g., CORESETPoolIndex).

[0232] The Rel-17 NR standard supports (1) MTRP PDCCH repetition transmission, (2) MTRP PDCCH single frequency network (SFN) transmission, (3) MTRP PDSCH SFN transmission, (4) S-DCI-based MTRP PUSCH repetition transmission, and (5) single PUCCH resource-based MTRP PUCCH repetition transmission. All of these transmission methods involve repeatedly transmitting the same content (i.e., DCI, UL / DL TB, or UCI) as a URLLC target enhancement to increase reliability. MTRP PDCCH repetition transmission is TDM or FDM repetition transmission, MTRP PDCCH / PDSCH SFN is repeated at the same time / frequency / layer, S-DCI-based MTRP PUSCH repetition transmission is TDM repetition transmission, and single PUCCH resource-based MTRP PUCCH repetition transmission is TDM repetition transmission.

[0233] (1) MTRP PDCCH Repeat Transmission

[0234] For MTRP PDCCH repeat transmission, multiple CORESETs with different TCI states (i.e., different QCL RSs) are configured in the UE, and multiple SS sets connected / associated with the CORESETs are configured in the UE. The base station instructs / configures the UE that a search space set (SS set) connected to one CORESET and an SS set connected to another CORESET are linked for repeat transmission, so that the UE knows that PDCCH candidates in the SS set are to be repeatedly transmitted.

[0235] For example, assume that two CORESETs, CORESET 0 and 1, are configured in a UE, and that CORESET 0 and 1 are linked to SS sets 0 and 1, respectively, and that SS sets 0 and 1 are linked. The UE can determine that the PDCCH candidate in SS set 0 and the PDCCH candidate in SS set 1 repeatedly transmit the same DCI, and that a specific PDCCH candidate in SS set 0 and a specific PDCCH candidate in SS set 1 are a pair configured to repeatedly transmit the same DCI according to a specific rule. These two PDCCH candidates are called linked PDCCH candidates, and the UE can successfully decode the DCI if it correctly receives either one of the two PDCCH candidates. However, when receiving PDCCH candidates for SS set 0, the QCL RS (i.e., DL beam) in the TCI state of COERSET 0 connected to SS set 0 is used, and when receiving PDCCH candidates for SS set 1, the QCL RS (i.e., DL beam) in the TCI state of COERSET 1 connected to SS set 1 is used, so that the connected PDCCH candidates are received in different beams.

[0236] (2) MTRP SFN PDCCH repetitive transmission

[0237] As a special case of MTRP PDCCH repetitive transmission, multiple TRPs may repeatedly transmit the same DCI at the same time / frequency / DMRS port, which can be called SFN PDCCH transmission. However, for SFN PDCCH transmission, the base station configures multiple TCI states in one CORESET instead of configuring multiple CORESETs with different TCI states in the UE. When the UE receives PDCCH candidates in the SS set connected to the single CORESET, it performs PDCCH DMRS channel estimation and attempts decoding using all of the multiple TCI states.

[0238] (3) MTRP SFN PDSCH repeat transmission

[0239] During the MTRP PDSCH repetition transmission, two TRPs repeatedly transmit the PDSCH on different resources. However, as a special case, when two TRPs use the same resources, i.e., when the same channel is repeatedly transmitted on the same frequency, time, and layer (i.e., DMRS port), the reliability of the channel can also be improved. In this case, the same channel repeatedly transmitted is not separated into resources and is received over the air, so it is recognized as a single channel from the perspective of the receiving end. For PDSCH SFN transmission, two DL TCI states for PDSCH DMRS reception may be configured.

[0240] (4) S-DCI-based MTRP PUSCH repetitive transmission

[0241] The base station configures two SRS sets in the UE for S-DCI-based MTRP PUSCH transmission, where each set is used to indicate the UL Tx port and UL beam / QCL information for TRP1 and TRP2, respectively. The base station also uses two SRI fields in one DCI to indicate SRS resources for each SRS set and can indicate up to two power control (PC) parameter sets. For example, the first SRI field can indicate the SRS resources and PC parameter set defined in SRS set 0, and the second SRI field can indicate the SRS resources and PC parameter set defined in SRS set 1. The UE receives the UL Tx port, PC parameter set, and UL beam / QCL information for TRP1 in the first SRI field and performs PUSCH transmission on the transmission occasion (TO) corresponding to SRS set 0. Similarly, the UE receives the UL Tx port, PC parameter set, and UL beam / QCL information for TRP2 in the second SRI field, and accordingly transmits PUSCH using the TO corresponding to SRS set 1. Here, the TOs corresponding to SRS sets 0 and 1 are determined by one of two mapping methods configured by the base station, namely, cyclic (beam) mapping or sequential (beam) mapping. For example, in the case of cyclic beam mapping, SRS set 0 and SRS set 1 are alternately mapped to the TOs. For example, if TO=4, TOs 1, 2, 3, and 4 are mapped to SRS sets 0, 1, 0, and 1, respectively. On the other hand, in sequential beam mapping, one SRS set is mapped to two adjacent TOs, and another SRS set is mapped to the next two adjacent TOs. For example, if TO=8, TOs 1, 2, 3, 4, 5, 6, 7, and 8 are mapped to SRS sets 0, 0, 1, 1, 0, 0, 1, and 1, respectively. This mapping scheme is also applied to PUCCH repetitions.

[0242] The existing single field has been expanded to two fields so that fields other than the SRI field, such as the transmit PMI (TPMI), phase tracking reference signal (PTRS), and transmission power control (TPC), can also be indicated for each TRP. In addition, a 2-bit SRS resource set indication field has been introduced, allowing one of two SRS sets to be selected for STRP PUSCH repetitive transmission, or both to be selected for MTRP PUSCH repetitive transmission. That is, when this field is 00 or 01, it indicates SRS set 0 or SRS set 1, respectively, and STRP PUSCH transmission corresponding to each SRS set is performed. When this field is 10 (SRS set 0, SRS set 1), it indicates that the SRS set pair is to be transmitted in the indicated order. That is, set 0 corresponds to the first PUSCH TO. If the value is 11, (SRS set 1, SRS set 0) is specified, and MTRP PUSCH transmission is performed in the specified set pair order. That is, set 1 corresponds to the first PUSCH TO.

[0243] (5) Single PUCCH resource-based MTRP PUCCH repetition transmission For single-PUCCH resource-based MTRP PUCCH transmission, the base station activates / configures two pieces of spatial relation information for a UE on a single PUCCH resource. Here, in FR1, two power control (PC) parameter sets may be activated / configured. When the UE transmits UL UCI on the PUCCH resource, each piece of spatial relation information is used to indicate spatial relation information for TRP1 and TRP2, respectively. For example, using the value indicated in the first piece of spatial relation information, the UE is instructed on Tx beam / PC parameters for TRP1, and the UE uses this information to transmit the PUCCH on the TO corresponding to TRP1. Similarly, using the value indicated in the second piece of spatial relation information, the UE is instructed on Tx beam / PC parameters for TRP2, and uses this information to transmit the PUCCH on the TO corresponding to TRP2.

[0244] In addition, for MTRP PUCCH repeated transmission, the configuration method has been enhanced so that two pieces of spatial relationship information can be configured in a PUCCH resource. That is, when PC parameters such as PLRS, Alpha, P0, and closed loop index are configured for each piece of spatial relationship information, a spatial relation RS can be configured. As a result, PC information and spatial relationship RS information corresponding to two TRPs can be configured using two pieces of spatial relationship information. In TO 1, the UE transmits UCI (i.e., CSI, HARQ-ACK, and scheduling request (SR)) on the PUCCH using the first spatial relationship information, and in TO 2, the UE transmits the same UCI (i.e., CSI, HARQ-ACK, and SR) on the PUCCH using the second spatial relationship information. In this disclosure, a PUCCH resource configured with two pieces of spatial relationship information is referred to as an MTRP PUCCH resource, and a PUCCH resource configured with one piece of spatial relationship information is referred to as an STRP PUCCH resource.

[0245] In the method proposed in this document, using ( / mapping) a specific TCI state (or TCI) when receiving data / DCI / UCI for a certain frequency / time / space resource can mean, in the case of DL, estimating a channel from DMRS using the QCL type and QCL RS indicated by the TCI state in that frequency / time / space resource, and receiving / demodulating data / DCI using the estimated channel, and in the case of UL, transmitting / modulating DMRS and data / UCI using the Tx beam and / or Tx power indicated by the TCI state in that frequency / time / space resource.

[0246] The UL TCI status includes Tx beam and / or Tx power information of the UE, and instead of the TCI status, other parameters such as spatial relation info may be used to configure the UE. The UL TCI status may be directly indicated in the UL grant DCI, or may represent spatial relation information of SRS resources indicated in the SRS resource indicator (SRI) field of the UL grant DCI. Alternatively, it may represent open-loop (OL) Tx power control parameters (j: index for open-loop parameters Po and alpha (maximum 32 parameter value sets per cell), q_d: index of DL RS for path loss (PL) measurement (maximum 3 measurements per cell), l: closed-loop power control process index (maximum 2 processes per cell)) linked to the value indicated in the SRI field of the UL grant DCI.

[0247] In addition, in Rel-17, both the DL TCI state and the UL TCI state can be indicated using DL DCI (e.g., DCI format 1-1 or 1-2), or only the UL TCI state can be indicated without indicating the DL TCI state. As a result, the method used for UL beam and power control (PC) configuration in the existing Rel-15 / 16 is replaced by the above-mentioned UL TCI state indication method in R-17. More specifically, in R17, one UL TCI state may be indicated in the TCI field of the DL DCI, and the UL TCI state may be applied to all PUSCHs and all PUCCHs after a certain time period called the beam application time, and may be applied to some or all of the indicated SRS resource sets.

[0248] Meanwhile, Rel-18 discusses a method in which a UE can simultaneously transmit multiple channels / reference signals (RS) of the same type or multiple channels / RS of different types. While existing UEs are limited in their ability to transmit multiple channels / RS at the same time (e.g., it is possible to simultaneously transmit multiple SRS resources of different SRS sets for UL beam measurement, but not multiple PUSCHs), future advanced UEs will be able to relax this limitation and simultaneously transmit multiple channels or RSs using multiple transmission panels. This transmission method can be called simultaneous transmission across multiple panels (STxMP), and such a UE can be called an STxMP UE. For example, two PUSCHs corresponding to two UL TBs may be scheduled on the same resource, and spatial relationship RS1 and PC parameter set 1 (i.e., UL TCI state 1) and spatial relationship RS2 and PC parameter set 2 (i.e., UL TCI state 2) may be configured for transmission of PUSCHs 1 and 2, respectively. In this case, the UE can transmit PUSCH 1 using panel 1 corresponding to UL TCI state 1 and simultaneously transmit PUSCH 2 using panel 2 corresponding to UL TCI state 2.

[0249] When a base station schedules a PUSCH using DCI, it can indicate whether the PUSCH should be transmitted in STxMP, in a single panel, or in MTRP PUSCH repetition. Of course, the UE must have STxMP capability, and the STxMP mode must be enabled in advance by RRC signaling, etc. For this purpose, the existing SRS resource set indication field may be redefined and used, or a new DCI field may be introduced.

[0250] For convenience of explanation, the present disclosure applies the proposed method assuming cooperative transmission / reception between two TRPs, but the application may be extended to a multi-TRP environment of three or more, and to a multi-panel environment. Different TRPs may be recognized by the UE as different TCI states, and the UE receiving / transmitting data / DCI / UCI using TCI state 1 means receiving / transmitting data / DCI / UCI from / to TRP1.

[0251] In this disclosure, a transmission occasion (TO) may refer to each channel transmitted at a different time when multiple channels are TDMed, or each channel transmitted on a different frequency / RB when multiple channels are FDMed, or each channel transmitted on a different layer / beam / DMRS port when multiple channels are SDMed. One TCI state may be mapped to each TO. When the same channel is repeatedly transmitted, complete DCI / data / UCI is transmitted to one TO, and the receiving end can receive multiple TOs, thereby increasing the success rate of reception.

[0252] Channel state information transmission and reception method In this disclosure, " / " can mean either the inclusion of all the content separated by the / (and) or the inclusion of only a portion of the separated content (or).

[0253] In this disclosure, when multiple base stations or a base station with multiple panels performs downlink transmission of a UE based on coherent joint transmission (CJT) (it is assumed that multiple base stations are connected by an ideal backhaul and therefore synchronized between the base stations), high-precision codebook design is considered to improve performance, and for this purpose, a method for configuring antenna ports and CSI-RS is proposed.

[0254] Codebooks supported in NR are broadly divided into two types (e.g., Type 1 CSI and Type 2 CSI). Type 1 CSI is divided into a single-panel codebook (CB) and a multi-panel CB. Type 1 CSI CB may be configured primarily targeting single-user (SU)-MIMO. The codebook is configured to select / indicate one or more preferred discrete Fourier transform (DFT) vectors for the UE from a set of oversampled DFT vectors based on the spatial domain (SD) and to indicate co-phase for cross polarization of the base station antenna. Type 2 CSI is a codebook primarily used to improve multi-user (MU)-MIMO performance by allowing the UE to select multiple SD-based DFT vectors and linearly combine them to form a high-resolution codebook. To address the drawback of Type 2 CSI introduced in Release 15 NR, which had a high payload, enhanced Type 2 (eType 2) CSI was introduced in Release 16 NR, which reduces the codebook payload by taking into account correlation on the frequency axis.

[0255] In this disclosure, we propose a codebook design that takes CJT into consideration, particularly a CJT codebook design that uses a linear combining-based type 2 sequence codebook.

[0256] In the method proposed in the present disclosure, the operation of the Type II codebook introduced in Rel (release)-15 / 16, as exemplified in Table 7 above, may be applied supplementarily / together to the operation / implementation of the method proposed in the present disclosure. Therefore, when describing the method proposed in the present disclosure hereinafter, the standard operation exemplified in Table 7 may be referred to.

[0257] FIG. 7 illustrates an example of an antenna configuration in a wireless communication system to which the present disclosure can be applied.

[0258] FIG. 7 illustrates an antenna configuration where (M, N, P, Mg, Ng) = (4, 4, 2, 2, 2). FIG. 7 illustrates an antenna configuration with a total of four panels, and each box represents one panel. M represents the number of columns in the panel, and N represents the number of rows in the panel. P represents polarization, where 1 represents co-polarization (co-pol) and 2 represents cross polarization (X-pol). Mg represents the number of panels in the first domain, and Ng represents the number of panels in the second domain. Here, the total number of antenna elements is P*M*N*Mg*Ng (2*4*4*2*2=128 in FIG. 7).

[0259] dgH represents the panel spacing in the first domain, and dgV represents the panel spacing in the second domain. dH represents the antenna spacing in the first domain, and dV represents the antenna spacing in the second domain.

[0260] Transceiver unit (or transmit / receive unit) (TXRU) virtualization can define the relationship between signals at the TXRU and signals at the antenna elements. In the antenna port configuration within the panel using TXRU virtualization, N1 represents the number of columns in the first domain, and N2 represents the number of rows in the second domain. Here, the total number of CSI-RS ports within the panel is P*N1*N2 (2*2*2=8 in FIG. 7).

[0261] FIG. 8 illustrates an example of an aggregated channel for CJT in a wireless communication system to which the present disclosure can be applied.

[0262] Referring to FIG. 8, N_TX_total refers to the sum of the number of transmit antennas (Tx antennas) of TRPs participating in the CJT, and N_TX_i refers to the number of transmit antennas of the i-th TRP. In the example of FIG. 8, N_TX_total = N_TX_1 + N_TX_2. And, N_RX refers to the receive antennas of the UE. N3 refers to the number of frequency units configured in the UE. In the example of FIG. 8, it can be analyzed as N3 subbands, but this is just one example, and the value of N3 may be defined as the number of resource blocks (RBs), resource elements (REs), or RB / RE groups.

[0263] H(i,j) is the channel value (matrix) corresponding to the jth frequency unit of the UE and the ith TRP. H_Merge_j is the channel value (matrix) corresponding to the jth frequency unit of the UE and the TRP participating in the CJT.

[0264] When a Rel-16 (eType II) codebook is constructed using the channel shown in FIG. 8, it is as shown in FIG.

[0265] FIG. 9 illustrates an example of an eType II codebook for CJT in a wireless communication system to which the present disclosure can be applied.

[0266] Referring to FIG. 9, W_1 and W_2 are final precoding matrices corresponding to the transmit antennas of each TRP, which can be expressed as Equation 3 below.

[0267]

number

[0268] where H can mean the Hermitian operation (conjugate transpose), which may be simply replaced by the transpose operation depending on the frequency domain (FD) basis design, and "η" is a normalization term.

[0269] The spatial domain (SD) basis vectors and frequency domain (FD) basis vectors are composed of DFT basis vectors. In particular, the SD basis vectors may be determined as 2D DFT or 1D DFT depending on the antenna structure of the TRP. Here, the DFT vectors are merely examples, and other basis vectors may be used. M is the number of FD basis vectors.

[0270] In the Rel-15 Type II codebook, among the oversampled discrete Fourier transform (DFT) vectors, L basis DFT vectors are used for each specific polarity. Then, a precoding matrix is ​​constructed by applying wideband (WB) amplitude coefficients and sub-band (SB) amplitude / phase coefficients to the basis DFT vectors. Among the oversampled DFT vectors, a specific vector is v l,m The standard is defined as in the following Equation 4.

[0271]

number

[0272] Here, N1 and N2 refer to the number of antennas (per polarization) in the first domain and second domain per TRP, respectively (i.e., the number of antenna ports), and may be set by the higher layer parameter n1-n2-codebookSubsetRestriction. O1 and O2 represent the oversampling factors of the first domain (or first dimension) and the second domain (or second dimension), respectively. The settings of (N1, N2) and (O1, O2) supported for a given number of CSI-RS ports may be defined in the standard.

[0273] L represents the number of beams, and the L value is set by the upper layer parameter numberOfBeams. CSI-RS When =4, L=2 and P CSI-RS >4, then L∈{2,3,4} may be the case.

[0274] Here, the index m1 as shown in the following formula 5 (i) and m2 (i) are applied to l and m in Equation 4, respectively, and a precoding matrix may be configured based on such DFT basis vectors.

[0275]

number

[0276] where i is 0, 1,...,L-1. n1 (i) ∈{0,1,...,N1-1}, n2 (i) ∈{0,1,...,N2-1}. q1∈{0,1,...,O1-1} and q2∈{0,1,...,O2-1}. n1 (i) and n2 (i) The value is determined by a standard-defined algorithm.

[0277] In the Rel-16 Type II codebook, the UE compresses and reports codebook information using frequency domain correlation for the above-mentioned Rel-15 Type II codebook. In this case, to compress the codebook information, the compressed information may be configured based on a set of vectors in an oversampled DFT codebook. Here, the set of vectors in an oversampled DFT codebook may be referred to as "frequency domain (FD) basis vectors."

[0278] M υ The FD basis vectors are defined in the standard way as shown in Equation 6 below.

[0279]

number

[0280] where f=0,1,...,M υ N3 is the total number of precoding matrices, l=1,...,v, where v is a rank indicator (RI) value.

[0281] As above, M υ Among the FD basis vectors, the t-th element of the f-th vector (where t=0,...,N3-1) is y t,l (f) and is defined in the standard as shown in Equation 7 below.

[0282]

number

[0283] where n 3,l is defined in the standard as Equation 8 below.

[0284]

number

[0285] where f=0,1,...,M υ -1. In the above formula, n 3,l (f) value, M selected by the terminal among the oversampled DFT codebook of size N3 (i.e., among the total number of precoding matrices). υ The FD basis vector combinations may be reported to the base station.

[0286] In addition, in the enhanced Type II codebook of Table 7 above, the precoding matrix may be indicated by the PMI reported by the UE to the base station, and the precoding matrix is ​​an L vector (i.e., the L value represents the number of beams and is set by the upper layer parameter numberOfBeams) + M υvectors (i.e., the number of FD basis vectors set by the base station), where the L vectors are 1,1 , i 1,2 where n1∈{0,1,...,N1-1} (number of antenna ports in the first dimension) and n2∈{0,1,...,N2-1} (number of antenna ports in the second dimension) are indicated by q1∈{0,1,...,O1-1} (oversampling values ​​in the first dimension) and q2∈{0,1,...,O2-1} (oversampling values ​​in the second dimension) may be identified by an index.

[0287] Here, the PMI corresponds to codebook indexes i1 and i2. As described in Table 7, i1 and i2 may each be composed of multiple indexes depending on the rank number (υ). That is, the PMI may include the indexes included in i1 and i2 (or indicators for indicating the indexes). For example, in the advanced Type II codebook, when υ=1, i1 is 1,1 ,i 1,2 ,i 1,5 ,i 1,6,1 ,i 1,7,1 ,i 1,8,1 As yet another example, when υ=2, i2 may include i 2,3,1 ,i 2,4,1 ,i 2,5,1 ,i 2,3,2 ,i 2,4,2 ,i 2,5,2 where i 2,4,l (l=1,2,3,4) corresponds to an amplitude coefficient indicator for indicating an amplitude coefficient. 2,5,l (l=1, 2, 3, 4) corresponds to a phase coefficient indicator for indicating a phase coefficient.

[0288] Referring again to Fig. 9, the codebook considered in this disclosure may be roughly composed of three parts: an SD basis part, a coefficient matrix part, and an FD basis part.

[0289] First, the SD basis (i.e., W SD For the sake of convenience, it is assumed below that two TRPs are associated with each other, but this is merely an example and the present disclosure is not limited thereto.

[0290]

number

[0291] Linear combining vectors (b1...b L ) size is N Tx where L is the number of basis vectors to be linearly combined. The reason why Equation 9 is written in the form of a block diagonalization matrix is ​​to take into account the cross-polarized (X-pol) antennas equipped in the base station (or TRP). FIG. 9 takes into account the same number of basis vectors and the same basis vectors for each polarization, and is a form suitable for considering a single TRP. However, this is merely an example, and the present disclosure is not limited thereto. If the above form is configured to be suitable for a multi-TRP form, it may be as shown in Equation 10 below.

[0292]

number

[0293] As shown in Equation 10, the SD basis is a set of basis vectors and their number (i.e., L i ) may be independently selected. i∈{2,4,6}. In addition, although Equation 10 illustrates a case where a common basis vector is selected for each polarization, the present disclosure is not limited to this. To set the proposal in the most flexible manner, the equation may be transformed as shown in the following Equation 11.

[0294]

number

[0295] As shown in Equation 11, the SD basis is a set of basis vectors and their number (i.e., L i,p Alternatively, the oversampling factor and / or type (e.g., DFT, DCT (discrete cosine transform)) of the basis for constructing the SD basis may be set independently for each TRP.

[0296] Furthermore, in Equation 10 and Equation 11, the order of each block is illustrated as the first polarization of TRP1 -> the first polarization of TRP2 -> the second polarization of TRP1 -> the second polarization of TRP2, but this is just an example, and the order may be changed depending on the CSI-RS configuration and antenna port mapping.

[0297] [Table 9]

[0298] The coupling matrix may be composed of complex values ​​and may be divided into an amplitude part and a phase part.

[0299] In the existing legacy codebook configuration method, amplitude is configured in two stages, and quantized with 4 bits between polarizations (i.e., the strongest coefficient is selected for each polarization, and the larger of these two coefficients is assumed to be 1, and the coefficients of the remaining polarizations are quantized with 4 bits), and within the same polarization, it is configured with 3 bits based on the strongest coefficient of each polarization.

[0300] Tables 8 and 9 show values ​​corresponding to each quantization payload. Table 8 illustrates inter-polarization quantization, and Table 9 illustrates intra-polarization quantization.

[0301] [Table 10]

[0302] [Table 11]

[0303] The phase is made up of 4 bits (for example, 16PSK), and 4-bit quantization is performed based on the strongest coefficient.

[0304] The following can be considered to improve the performance of CSI measurement and reporting in the M-TRP CJT:

[0305] The Rel-18 CJT codebook may be configured as Mode 1 or Mode 2 by higher layer signaling (e.g., RRC signaling). In Mode 3, all TRPs are restricted to use the same FD basis, and thus the codebook may be represented as shown in FIG. 9. Meanwhile, in Mode 1, different FD bases may be configured for each TRP, and the codebook for each TRP may be represented by a different M by N3 (i.e., M number of rows and N3 number of columns) basis matrix.

[0306] The following was agreed upon at the 3GPP standardization meeting:

[0307] i) In selecting the SD basis for improving the Type-II codebook for CJT mTRP, the following is supported for the L parameter:

[0308] - L per CSI-RS resource n Parameters

[0309] [Table 12]

[0310] L n The values ​​are determined in a predefined set.

[0311] ii) In Type-II codebook improvements for CJT mTRP, for a given CSI-RS resource in relation to the codebook parameters, the supported values ​​of the following parameters follow the legacy (Rel-16 General eType-II and Rel-17 PS FeType-II) specifications:

[0312] - N1, N2, N3, O1, O2

[0313] - M (applicable only to Rel-17 PS FeType-II base designs)

[0314] For the following parameters, RAN1#111 determines whether the supported values ​​comply with legacy (Rel-16 General eType-II and Rel-17 PS FeType-II) specifications or whether additional improvements are required.

[0315] R: Inclusive, for example, supports only R=1 or supports larger R values

[0316] -M v / p v (Rel-16 General eType-II): For example, for v=1, 2, smaller p such as {1 / 8, 1 / 4, 1 / 2} v Supporting values ​​or removing larger legacy values

[0317] - β: inclusive, supports smaller values ​​such as {1 / 16, 1 / 8, 3 / 8}

[0318] Note: The parameter argument results further restrict the supported combinations of parameter values.

[0319] If N>1, will the maximum 2N1N2 (which is the same as the number of CSI-RS ports used for channel measurement resource (CMR)) be limited to 32, as in legacy specifications?

[0320] In the legacy NR standard, the L, p, and beta (β) values ​​are signaled by RRC in the form of a combination. For example, the parameter combination is signaled using the RRC parameter paramCombination-r16, and the L, p, and beta (β) values ​​are determined using the predefined Table 10 below.

[0321] Table 10 shows the parameter combinations for L, p, and beta (β).

[0322] [Table 13]

[0323] Each parameter (L, p, beta (β)) can be used to determine the number of FD bases M using the following formula, or to calculate K0, which represents the upper bound on the number of non-zero coefficients.

[0324] As described above, a precoding matrix may be indicated by the PMI reported by the UE to the base station, and the precoding matrix is ​​a vector of L (i.e., the number of SD basis vectors) for each TRP + M (i.e., the number of FD basis vectors, where M is M for each layer). υ ) vector. In other words, the precoding matrix may be determined (by a linear combination) from the SD basis vectors and the FD basis vectors.

[0325] Here, N3 means the DFT size for FD compression, and N3 = N SB ×R. N SB N may correspond to the number of subbands, and R may be set by higher layer signaling. That is, N may represent the total number of precoding matrices indicated by the PMI.

[0326] [Table 14]

[0327] That is, K0 may be derived / determined using the beta (β) value, the L value, and the M value. As described above, the PMI corresponds to the codebook indexes i1 and i2. In other words, the PMI may include the codebook indexes included in i1 and i2 (or indicators for indicating the indexes, etc.). Here, the codebook index may include an amplitude coefficient indicator (e.g., i 2,4,l(l=1,...,υ)) and a phase coefficient indicator (e.g., i 2,5,l (l=1,...,v)). The codebook index may also include a bitmap (e.g., i 1,7,l (l=1,...,v)), where K0 may correspond to an upper bound of non-zero coefficients in the amplitude coefficient and phase coefficient (e.g., for each layer).

[0328] More specifically, the bitmap is 2,4,l (l=1,...,υ) (i.e., amplitude coefficient indicator) and i 2,5,l Identify the coefficients to be reported in (l=1,...,υ) (i.e., phase coefficient indicators), where in the bitmap, bits with non-zero values ​​represent reported coefficients and bits with zero values ​​represent unreported coefficients.

[0329] The length of the bitmap is determined by the number of L vectors and M υ The bitmap may be determined based on the number of vectors, i.e., each bit in the bitmap may be determined based on the number of vectors, L, and M. υ The bitmap may correspond to an amplitude coefficient and a phase coefficient for each combination with a vector (i.e., a combination of an SD basis and an FD basis). That is, one bit may correspond to an amplitude coefficient, and one bit may correspond to a phase coefficient. Here, when the value of a specific bit in the bitmap is 0, the report of the amplitude coefficient or phase coefficient corresponding to the specific bit may be omitted (i.e., the amplitude coefficient indicator i2,4,l or phase coefficient indicator i 2,5,l (The reporting of the bitmap is omitted.) The bitmap for each layer may consist of a maximum of K0 = [β × 2LM] bits.

[0330] As described above, the L value may be set separately / differently for each TRP, and the L value for the nth TRP is set to L n In addition, the M value may be set to a common value for the TRP. That is, the number of FD basis vectors for each TRP is equal to M. That is, the precoding matrix is ​​L for each TRP. n The M value may be determined from a vector of the total number of values ​​(i.e., SD basis vectors for all TRPs) and a vector of M (FD basis vectors common to all TRPs). As described above, the M value may be determined using the p value.

[0331] [Table 15]

[0332] Example 1: The following scheme is proposed to signal / determine the combination for L, p, and beta in the CJT codebook.

[0333] Example 1-1) TRP-specific L n value (where n is the total number of TRPs, i.e., n=1,...,N TRP ) applies, the legacy table in Table 10 with a single L value cannot be used. n The value may be signaled / determined separately from p,beta (e.g., RRC signaling), and p,beta may be signaled / determined in combination (e.g., RRC signaling). n The values ​​are for each L n The value may be signaled or a predefined L nThe p,beta (β) value may be determined by signaling a single piece of information (e.g., an RRC parameter) to indicate a combination of p,beta values. For example, the p,beta (β) value may be determined by an index value indicated by an RRC parameter in a predefined table.

[0334] Example 1-2) L n The value may be signaled / determined separately by the method of Example 1-1 above. Then, the signaled / determined L n A representative value is determined from the L n The combination of the representative values ​​of p and beta may be signaled in a similar manner to existing methods.

[0335] For example, the set L n A representative value may be determined from the values, and the representative value may be analyzed as the L value in Table 10. That is, the representative value may be analyzed as the L value in Table 1 for p and beta values. For example, if the representative value is 4, p and beta values ​​may be set / determined by one of combinations 3, 4, 5, and 6 corresponding to L=4. In other words, the base station may instruct / set one of combinations 3, 4, 5, and 6, and p and beta values ​​may be determined by the instructed / set combination. Here, L n The typical value for the value is L n The maximum value of the L n may be defined as various values ​​using n The typical value for the value is L n The minimum of the values ​​may be determined, or L n The typical value for the value is L n Alternatively, the base station may determine the sum of L n When the maximum value of the sum is set for the value, the set value may be determined. n In addition to using max / min / sum as an operation to determine a representative value for a value, various other operations may be used to determine the representative value.

[0336] Also, L n When determining a representative value among the values, the first L1 value (=L value corresponding to the first TRP) may be determined as the representative value. In other words, the first L1 value may refer to the L value corresponding to the first CSI-RS resource among K NZP CSI-RS resources configured as CMRs for CJT CSI feedback. Alternatively, the first L1 value may refer to the L value corresponding to the CSI-RS resource with the lowest or highest ID (identifier). In this case, L1 may be indicated / set by joint encoding with other codebook parameters (i.e., p, beta) as in the existing scheme, and the remaining L values ​​may be indicated / set by separate signaling (e.g., RRC signaling). Here, the remaining L values ​​other than L1 (e.g., L2, L3, ..., L n ) may be limited to be set equal to or less than the L1 value. Alternatively, each remaining L value other than L1 (e.g., L2, L3, ..., L n ) may be set to multiple values ​​instead of a single value. When multiple values ​​are set, the UE may n ) can be selected and reported to the base station. In the above example, the first L1 value is set as the representative value, but the present disclosure is not limited to this, and another specific value other than the first value may be determined as the representative value.

[0337] Example 1-3) Using the existing method, each L n The value is L n ,p, and beta combination parameters (e.g., paramCombination-r16) may be signaled / determined (using Table 10 above). For example, combination 1 (i.e., L1=2, p=1 / 4, 1 / 8, beta=1 / 4) may be set for L1,p, and beta, and combination 2 (i.e., L2=2, p=1 / 4, 1 / 8, beta=1 / 2) may be set for L2,p, and beta. nSince there are multiple (two in the above example) (in the case of multiple TRPs), each L n There will be multiple p's signaled along with L1, and multiple betas. In this case, the maximum (or minimum) value among the multiple p's and / or betas may be determined as one representative value. That is, in the above example, two beta values, 1 / 4 and 1 / 2, are set, so the maximum value, 1 / 2, may be determined as the final beta, or the minimum value, 1 / 4, may be determined as the final beta. The p value may be determined similarly. In the above example, the p value signaled along with L1 and the p value signaled along with L2 are the same, so the representative value does not need to be calculated using maximum / minimum values, etc. In addition to max / min / sum, various other calculations may be used to determine the representative value for the p and / or beta values.

[0338] Alternatively, to determine the L value and the remaining jointly encoded codebook parameters (e.g., p, beta) (i.e., to determine one of multiple values), the UE may select a specific L n The values ​​of the remaining codebook parameters (e.g., p, beta) jointly coded with the n The values ​​of the remaining jointly coded codebook parameters (e.g., p, beta) are ignored. n The value is the L n The representative value (e.g., L n Maximum / minimum value of the value or the first L1 value or L at a specific position n The value of L can be determined by using a method for determining the n When L1 is determined as a representative value among the values, the UE can assume that the values ​​of the remaining codebook parameters (eg, p, beta) jointly coded with L1 are valid values.

[0339] Example 1-4) The base station sends K (=number of TRPs, i.e., N TRP) CSI-RS resources can be configured. In this case, the K value may define separate / different configurable parameter combinations for L, p, and beta. For example, in combination with Example 1-1, L n (n=1,...,N TRP ) value and p, beta combinations are signaled separately, L n (n=1,...,N TRP ) values ​​and combinations of p and beta may be defined.

[0340] For example, a parameter combination table defining configurable parameter combinations for L, p, and beta may be defined separately / differently depending on the value of K. As the value of K increases, the codebook payload size increases, and in consideration of such feedback overhead, parameter combinations (or parameter combination tables) configurable depending on the value of K may be defined separately / differently depending on each other.

[0341] Alternatively, configurable parameter combinations (or parameter combination tables) for L, p, and beta may be commonly defined (e.g., using one table). In this case, the L, p, and beta values ​​determined from the parameter combinations (or parameter combination tables) configurable by signaling by the base station may be determined as a function of the value K. For example, when determining the beta (or p) value, the beta (or p) value may be determined by multiplying the value determined from the parameter combinations (or parameter combination tables) configurable by signaling by the base station by 1 / K. In this way, the beta (or p) value may be set to a smaller value as K increases. As yet another example, the value determined from the parameter combinations (or parameter combination tables) configurable by signaling by the base station may be multiplied by K, and the beta (or p) value may be set to a larger value as the value K increases.

[0342] Also, in Examples 1-1, 1-2, 1-3, and 1-4, a UE may select a portion (=N, where N is a natural number) of TRPs (i.e., the number of TRPs that can participate in CJT transmission) to calculate CJT CSI. In this case, L / beta / p, etc. may be determined by the value N instead of the value K in the above proposal. That is, separate / different configurable parameter combinations may be defined depending on the value N for L, p, and beta. Alternatively, configurable parameter combinations (or parameter combination tables) for L, p, and beta may be commonly defined, and the L, p, and beta values ​​determined from the configurable parameter combinations (or parameter combination tables) by signaling from the base station may be determined as a function of the value N. That is, Examples 1-2 and 1-3 may be applied to only the value L corresponding to N TRPs. For example, when K=4 is set and CSI-RS resources 1, 2, 3, and 4 are configured as CJT CMR, the UE can select CSI-RS resources 2 and 3 (i.e., N=2) to calculate the CJT CSI. In this case, Example 1-2 or Example 1-3 does not apply to L1, L2, L3, and L4 (corresponding to CSI-RS resources 1, 2, 3, and 4, respectively), but may apply only to L2 and L3 (corresponding to CSI-RS resources 2 and 3, respectively) that correspond to the CSI-RS resources selected by the UE (i.e., L1 and L4 are assumed / regarded as not being configured). For example, in this case, the first L value corresponds to L2, not L1.

[0343] Alternatively, in Examples 1-1, 1-2, 1-3, and 1-4, the base station may set the maximum number of TRPs (=N TRP ) can be signaled to the UE. In this case, N can be used instead of K in the above proposal. TRP The values ​​may determine L / beta / p, etc., i.e., N for L, p, and beta. TRPAlternatively, the configurable parameter combinations (or parameter combination tables) for L, p, and beta may be commonly defined, and the L, p, and beta values ​​determined from the configurable parameter combinations (or parameter combination tables) by signaling from the base station may be determined by N TRP The value may be determined as a function of the

[0344] Meanwhile, in Examples 1-1, 1-2, 1-3, and 1-4, each TRP refers to a CSI-RS with a different QCL source reference signal (RS). That is, to calculate the CJT codebook, a UE may configure K CSI-RSs (K is a natural number greater than or equal to 2) with different QCL source RSs in a channel measurement resource (CMR), which refers to K TRPs that can participate in CJT transmission in the present disclosure. Therefore, in the present disclosure, each TRP may be analyzed as a CSI-RS with a different QCL source RS.

[0345] Furthermore, in Examples 1-1, 1-2, 1-3, and 1-4, the base station n For values ​​(i.e., L1, L2, ..., L n A plurality of candidate values ​​are set (for each value), and the UE selects one of the set candidate values ​​as the L n As described above, in Examples 1-1, 1-2, 1-3, and 1-4, each L n It is assumed that the value is set to one value. Therefore, each L n If multiple values ​​are set (i.e., multiple candidate values ​​are set), each L n The maximum / minimum value among the multiple values ​​may be assumed as the value, and Examples 1-1, 1-2, 1-3, and 1-4 may be applied. n As for the value, the values ​​determined / reported by the UE may be assumed and Examples 1-1, 1-2, 1-3, and 1-4 may be applied.

[0346] Meanwhile, the non-zero coefficient (NZC) bitmap corresponding to the n-th TRP (e.g., i 1,7,l (l=1,...,υ)) bitmap size (=B n ) is B n =2L n M v (where M v means the number of FD bases corresponding to layer v). Here, the UE selects K CSI-RS resources (=N TRPs) and assigns B n For example, if the UE selects CSI-RS resources 1 and 2 from CSI-RS resources 1, 2, 3, and 4 (i.e., K=4, N=2), the UE configures the bitmap to sizes B1 and B2, respectively, so that B3=B4=0. Therefore, the total bitmap size is B1+B2. As a result, the total size of the bitmap increases as the value of N selected by the UE increases (i.e., as the number of CSI-RS resources (TRPs) increases). To reduce the increase in bitmap size, the total size of the bitmap is increased by the value of N. n The values ​​may be set differently. For example, n When the N value is 1, the specific L n = 6, and when N is 2, L n = 4, and when N is 3, L n = 2. As another example, as the N value increases, L n Scaling down the values ​​(e.g., every time the N value increases by 1, a value smaller than 1 is used as the previous L n (scaled down by a fixed factor by multiplying the value) n Or, conversely, since the N value decreases, L n Scaling up the values ​​(e.g., every time the N value is decreased by 1, a value greater than 1 is added to the previous L n You can consider scaling up the value by a fixed factor (by multiplying the value). nThe value may be set in the set L n Multiple sets for each value may be configured. In this case, if the UE selects an N value equal to or less than a specific value (i.e., a small number of CSI-RS resources (TRPs)), a set configured with a relatively large L value (e.g., the largest L value) may be used. Conversely, if the UE selects an N value exceeding a specific value (i.e., a large number of CSI-RS resources (TRPs)), a set configured with a relatively small L value (e.g., the smallest L value) may be used. For example, if set 1={L1=4, L2=6, L3=6, L4=6} and set 2={L1=2, L2=2, L3=2, L4=2} are configured, if the UE selects an N value equal to or less than a specific value, it can use set 1 configured with a large L value, and otherwise it can use set 2 configured with a small L value.

[0347] On the other hand, UE is n The sum of the values ​​(i.e., L1+L2+L3+...+L K ) can be reported to the base station as the UE capability. In this case, the base station n When setting / instructing a value to the UE, L must be within the range not exceeding the maximum value reported by the UE. n Values ​​can be set / instructed. n If the sum of the values ​​is too large, the UE must search / select more SD basis vectors and calculate more non-zero coefficients when constructing the codebook. This may increase the implementation burden on the UE and also increase the feedback overhead. Therefore, the UE should select the L that matches its capabilities. n The sum of the values ​​(i.e., L1+L2+L3+...+L K ) can be reported to the base station as the UE capability. n The maximum value of the sum of the values ​​may be set / determined to vary depending on the K value.

[0348] FIG. 10 is a diagram illustrating a signaling procedure between a network and a UE for a channel state information transmitting and receiving method according to an embodiment of the present disclosure.

[0349] FIG. 10 illustrates an example of signaling between a network (e.g., TRP 1, TRP 2) and a terminal (i.e., UE) in a multiple TRP (i.e., M-TRP or multiple cells; hereinafter, any TRP may be referred to as a cell) situation to which the method proposed in the present disclosure (e.g., any one or a combination of one or more of Examples 1-1, 1-2, 1-3, and 1-4) can be applied.

[0350] Here, the UE / network are merely examples, and may be replaced with various devices as described later in Figure 13. Figure 10 is merely for convenience of explanation and does not limit the scope of the present disclosure. Also, some steps shown in Figure 10 may be omitted depending on the situation and / or settings.

[0351] In the following description, a network may be a base station including multiple TRPs or a cell including multiple TRPs. As an example, an ideal / non-ideal backhaul may be configured between TRP1 and TRP2 constituting the network. The following description is based on multiple TRPs, but this may equally be extended to transmissions via multiple panels. In addition, in the present disclosure, the operation of a UE receiving a signal from TRP1 / TRP2 may also be analyzed / described (or may be an operation) as the UE receiving a signal from the network (through / using TRP1 / TRP2), and the operation of a UE transmitting a signal to TRP1 / TRP2 may also be analyzed / described (or may be an operation) as the UE transmitting a signal to the network (through / using TRP1 / TRP2), and vice versa.

[0352] Also, as described above, 'TRP' may be applied in other words to expressions such as a panel, an antenna array, a cell (e.g., a macro cell / small cell / pico cell, etc.), a transmission point (TP), a base station (gNB, etc.), etc. As described above, a TRP may be distinguished by information (e.g., an index, an identifier (ID)) related to a CORESET group (or a CORESET pool). For example, if one UE is configured to transmit and receive data with multiple TRPs (or cells), this may mean that multiple CORESET groups (or CORESET pools) are configured for one UE. Such configuration of a CORESET group (or CORESET pool) may be performed by higher layer signaling (e.g., RRC signaling, etc.). Also, a base station may be a general term for an object that transmits and receives data to and from a UE. For example, the base station may be a concept including one or more TPs (Transmission Points), one or more TRPs (Transmission and Reception Points), etc. Furthermore, the TPs and / or TRPs may include a panel of the base station, a transmission and reception unit, etc.

[0353] Referring to FIG. 10, for convenience of explanation, signaling between one network (base station) and a UE is considered, but it goes without saying that the signaling method may be extended to signaling between multiple TRPs and multiple UEs.

[0354] Although not shown in Figure 10, the UE can transmit information about UE capabilities to the network. For example, the information about UE capabilities may include information related to UE capabilities associated with the proposed methods described above (e.g., any one or a combination of one or more of Examples 1-1, 1-2, 1-3, and 1-4), such as L nThe sum of the values ​​(i.e., L1+L2+L3+...+L K ) may include a maximum value of

[0355] 10, the network transmits channel state information (CSI) and related configuration information to the UE (S1001). That is, the UE receives channel state information (CSI) and related configuration information from the network.

[0356] The configuration information related to the CSI may include at least one of CSI-IM (interference management) resource configuration information, CSI measurement configuration information, CSI resource configuration information, and CSI report configuration information.

[0357] In addition, the configuration information related to the CSI (especially, the configuration information related to the CSI report) may include information regarding the proposed method described above (e.g., any one or a combination of one or more of Examples 1-1, 1-2, 1-3, and 1-4).

[0358] For example, according to the above-mentioned embodiment 1-1, the setting information includes: i) one or more first parameters (L n ,n=1,...,N TRP ii) information about the combination of the second parameter (p) and the third parameter (beta).

[0359] For example, according to the above-mentioned embodiment 1-2, the setting information includes one or more first parameters (L n ,n=1,...,N TRP ) and may include information about one or more first parameters (L n ,n=1,...,N TRP ) and information about the combination of the second parameter (p) and the third parameter (beta).

[0360] For example, according to the above-mentioned embodiments 1-3, the setting information may include one or more pieces of information for a combination of the first parameter (L), the second parameter (p), and the third parameter (beta). When a plurality of second parameters (p) and a plurality of third parameters (beta) are set, each of the second parameters (p) and the third parameter (beta) may be determined as a representative value.

[0361] For example, according to the above-described embodiments 1-4, the configuration information (especially, the configuration information related to the CSI resource) is set to K (= the number of TRPs, i.e., N TRP ) CSI-RS resources. In this case, the K value may define separate / different configurable parameter combinations for L, p, and beta. For example, in combination with Example 1-1, L n (n=1,...,N TRP ) value and the combination of p and beta are signaled separately, L n (n=1,...,N TRP ) value and a combination of p and beta. That is, the UE may define a configurable parameter combination between L n (n=1,...,N TRP ) value and the combination of p and beta can be assumed to be signaled.

[0362] The network transmits CSI-RS to the UE on one or more (i.e., K, where K is a natural number) CSI-RS resources (S1002). That is, the UE receives CSI-RS from the network on one or more (i.e., K, where K is a natural number) CSI-RS resources.

[0363] Here, the UE can receive CSI-RS through one or more antenna ports on one or more CSI-RS resources based on the configuration information.

[0364] The network receives channel state information (CSI) (feedback / report) from the UE (S1003), i.e., the UE transmits channel state information (CSI) (feedback / report) to the network.

[0365] Here, the channel state information (CSI) (feedback / report) may be transmitted on an uplink physical layer channel (e.g., PUCCH or PUSCH), and the CSI may include at least one of PMI, CQI, RI, and LI.

[0366] The CSI reported by the UE to the network may be derived / generated based on the proposed method described above (for example, any one or a combination of one or more of Examples 1-1, 1-2, 1-3, and 1-4).

[0367] For example, the CSI may include a PMI corresponding to an index of a codebook for indicating a precoding matrix. Here, the codebook may correspond to a codebook based on a linear combination of SD basis vectors and FD basis vectors as illustrated in FIG. 9, and the type of the codebook may be, for example, a Type II CJT (coherent joint transmission) codebook.

[0368] The precoding matrix indicated by the PMI may be determined from the plurality of vectors. In other words, the precoding matrix indicated by the PMI is determined by the L n (i.e., the number of SD basis vectors) vectors + M (i.e., the number of FD basis vectors, where M is M for each layer) υ may be denoted as: . ) vector.

[0369] The K CSI-RS resources may correspond to different TRPs. That is, each CSI-RS resource may correspond to a different TRP. Here, the UE may select N (1≦N≦K) CSI-RS resources from the configured K CSI-RS resources, calculate / derive PMI values ​​for the N (1≦N≦K) CSI-RS resources, and report them to the base station. In this case, the precoding matrix indicated by the PMI may be determined from vectors (i.e., SD basis vectors) corresponding to the selected N CSI-RS resources and M vectors (i.e., FD basis vectors).

[0370] The number of the plurality of vectors (i.e., the number of SD basis vectors and the number of FD basis vectors) is determined by the one or more first parameters (L n ,n=1,...,N TRP ) and the second parameter (p). n ,n=1,...,N TRP ) may correspond one-to-one to the K CSI-RS resources. n ,n=1,...,N TRP ) may indicate the number of SD basis vectors associated with the corresponding CSI-RS resource. Here, when a UE calculates / derives PMI values ​​for N (1≦N≦K) CSI-RS resources and reports them to a base station, one or more first parameters (L n ,n=1,...,N TRP ) may be used. Also, the second parameter (p) may be used to determine the number of FD basis vectors common to the K CSI-RS resources (or common to the N CSI-RS resources selected by the UE).

[0371] As described above, the PMI corresponds to codebook indexes i1 and i2. i1 and i2 may each be composed of a plurality of codebook indexes according to the rank number (v). The codebook index may include various indexes, and in particular, an amplitude coefficient indicator (e.g., i 2,4,l (l=1,...,υ)) and a phase coefficient indicator (e.g., i 2,5,l (l=1,...,v)). The codebook index may also include a bitmap for identifying which coefficients are reported by the amplitude coefficient indicator and the phase coefficient indicator (i.e., a bitmap for indicating non-zero coefficients among one or more amplitude coefficients and one or more phase coefficients) (e.g., i 1,7,l (l=1,...,v)), where the upper bound of non-zero coefficients in the amplitude coefficient and the phase coefficient (i.e., the non-zero coefficients do not exceed the upper bound) is determined by the one or more first parameters (L n ,n=1,...,N TRP ), the second parameter (p), and the third parameter (beta).

[0372] [Table 16]

[0373] The network may then transmit DCI scheduling the PDSCH to the UE, i.e., the UE may receive DCI scheduling the PDSCH from the network. Here, the DCI may be transmitted on a physical channel (e.g., a PDCCH). The DCI may include scheduling information for the PDSCH. The DCI may also include beam information for PDSCH transmission. For example, the beam information may include at least one of a quasi co-location (QCL) source and a TCI state index.

[0374] The network may then transmit downlink data to the UE, i.e., the UE may receive downlink data from the network, where the downlink data may be transmitted on a physical channel (e.g., a PDSCH).

[0375] FIG. 11 is a diagram illustrating an operation of a UE with respect to a channel state information transmitting and receiving method according to an embodiment of the present disclosure.

[0376] FIG. 11 illustrates an example of a UE operation based on the proposed method (e.g., any one or a combination of one or more of Examples 1-1, 1-2, 1-3, and 1-4). The illustration in FIG. 11 is for convenience of explanation and does not limit the scope of the present disclosure. Some steps illustrated in FIG. 11 may be omitted depending on the situation and / or setting. Also, the UE in FIG. 11 is an example and may be embodied by the device illustrated in FIG. 13. For example, the processor 102 / 202 in FIG. 13 may control the transceiver 106 / 206 to transmit and receive channels / signals / data / information, etc., and may control the memory 104 / 204 to store the transmitted or received channels / signals / data / information, etc.

[0377] Although not shown in Figure 11, the UE can transmit information about UE capabilities to the base station. For example, the information about UE capabilities may include information related to the UE capabilities associated with the proposed method described above (e.g., any one or a combination of one or more of Examples 1-1, 1-2, 1-3, and 1-4), such as L n The sum of the values ​​(i.e., L1+L2+L3+...+L K ) may include a maximum value of

[0378] Referring to FIG. 11, a UE receives channel state information (CSI) and related configuration information from a base station (S1101).

[0379] The configuration information related to the CSI may include at least one of CSI-IM (interference management) resource configuration information, CSI measurement configuration information, CSI resource configuration information, and CSI report configuration information.

[0380] In addition, the configuration information related to the CSI (particularly, for example, configuration information related to CSI reporting) may include information regarding the proposed method described above (for example, any one or a combination of one or more of Examples 1-1, 1-2, 1-3, and 1-4).

[0381] For example, according to the above-mentioned embodiment 1-1, the setting information includes: i) one or more first parameters (L n ,n=1,...,N TRP ii) information about the combination of the second parameter (p) and the third parameter (beta).

[0382] For example, according to the above-mentioned embodiment 1-2, the setting information includes one or more first parameters (L n ,n=1,...,N TRP ) may contain information. And one or more first parameters (L n,n=1,...,N TRP ) and information about the combination of the second parameter (p) and the third parameter (beta).

[0383] For example, in the above-described embodiments 1-3, the setting information may include one or more pieces of information for a combination of the first parameter (L), the second parameter (p), and the third parameter (beta). When a plurality of second parameters (p) and a plurality of third parameters (beta) are set, each of the second parameters (p) and the third parameter (beta) may be determined as a representative value.

[0384] For example, according to the above-described embodiments 1-4, the configuration information (e.g., configuration information related to CSI resources) is set to K (= the number of TRPs, i.e., N TRP ) CSI-RS resources. In this case, the K value may define separate / different configurable parameter combinations for L, p, and beta. For example, in combination with Example 1-1, L n (n=1,...,N TRP ) value and p, beta combinations are signaled separately, L n (n=1,...,N TRP ) value and a combination of p and beta. That is, the UE may define a configurable parameter combination between L n (n=1,...,N TRP ) value and the combination of p and beta can be assumed to be signaled.

[0385] The UE receives CSI-RS from the base station on one or more (ie, K, where K is a natural number) CSI-RS resources (S1102).

[0386] Here, the UE can receive CSI-RS through one or more antenna ports on one or more CSI-RS resources based on the configuration information.

[0387] The UE transmits channel state information (CSI) (feedback / report) to the base station (S1103).

[0388] Here, the channel state information (CSI) (feedback / report) may be transmitted on an uplink physical layer channel (e.g., PUCCH or PUSCH), and the CSI may include at least one of PMI, CQI, RI, and LI.

[0389] The CSI reported by the UE to the base station may be derived / generated based on the above-described proposed method (for example, any one or a combination of one or more of Examples 1-1, 1-2, 1-3, and 1-4).

[0390] For example, the CSI may include a PMI corresponding to an index of a codebook for indicating a precoding matrix. Here, the codebook may correspond to a codebook based on a linear combination of a D basis vector and an FD basis vector, as illustrated in FIG. 9, and the type of the codebook may be, for example, a Type II CJT (coherent joint transmission) codebook.

[0391] The precoding matrix indicated by the PMI may be determined from the plurality of vectors. In other words, the precoding matrix indicated by the PMI is determined by the L n (i.e., the number of SD basis vectors) vectors + M (i.e., the number of FD basis vectors, where M is M for each layer) υ may be denoted as . It may be determined from the vector of .

[0392] The K CSI-RS resources may correspond to different TRPs. That is, each CSI-RS resource may correspond to a different TRP. Here, the UE may select N (1≦N≦K) CSI-RS resources from the configured K CSI-RS resources, calculate / derive PMI values ​​for the N (1≦N≦K) CSI-RS resources, and report them to the base station. In this case, the precoding matrix indicated by the PMI may be determined from vectors (i.e., SD basis vectors) corresponding to the selected N CSI-RS resources and M vectors (i.e., FD basis vectors).

[0393] The number of the plurality of vectors (i.e., the number of SD basis vectors and the number of FD basis vectors) is determined by the one or more first parameters (L n ,n=1,...,N TRP ) and the second parameter (p). n ,n=1,...,N TRP ) may correspond one-to-one to the K CSI-RS resources. n ,n=1,...,N TRP ) may indicate the number of SD basis vectors associated with the corresponding CSI-RS resource. Here, when the UE calculates / derives PMI values ​​for N (1≦N≦K) CSI-RS resources and reports them to the base station, one or more first parameters (L n ,n=1,...,N TRP ) may be used. Also, the number of FD basis vectors common to the K CSI-RS resources (or common to the N CSI-RS resources selected by the UE) may be determined using the second parameter (p).

[0394] As described above, the PMI corresponds to codebook indexes i1 and i2. i1 and i2 may each be composed of a plurality of codebook indexes according to the rank number (v). The codebook index may include various indexes, and in particular, an amplitude coefficient indicator (e.g., i 2,4,l (l=1,...,υ)) and a phase coefficient indicator (e.g., i 2,5,l (l=1,...,v)). The codebook index may also include a bitmap for identifying which coefficients are reported by the amplitude coefficient indicator and the phase coefficient indicator (i.e., a bitmap for indicating non-zero coefficients among one or more amplitude coefficients and one or more phase coefficients) (e.g., i 1,7,l (l=1,...,v)), where the upper bound of non-zero coefficients in the amplitude coefficient and the phase coefficient (i.e., the non-zero coefficients do not exceed the upper bound) is determined by the one or more first parameters (L n ,n=1,...,N TRP ), the second parameter (p), and the third parameter (beta).

[0395] [Table 17]

[0396] FIG. 12 is a diagram illustrating an operation of a base station for a channel state information transmitting and receiving method according to an embodiment of the present disclosure.

[0397] FIG. 12 illustrates an example of the operation of a base station based on the previously proposed method (e.g., any one or a combination of one or more of Examples 1-1, 1-2, 1-3, and 1-4). The illustration in FIG. 12 is for convenience of explanation and does not limit the scope of the present disclosure. Some steps illustrated in FIG. 12 may be omitted depending on the situation and / or setting. Also, the base station in FIG. 12 is only an example and may be embodied by the device illustrated in FIG. 13. For example, the processor 102 / 202 in FIG. 13 may control the transceiver 106 / 206 to transmit and receive channels / signals / data / information, etc., and may control the memory 104 / 204 to store the transmitted or received channels / signals / data / information, etc.

[0398] Although not shown in Figure 12, the base station may receive information about UE capabilities from the UE. For example, the information about UE capabilities may include information related to UE capabilities associated with the proposed method described above (e.g., any one or a combination of one or more of Examples 1-1, 1-2, 1-3, and 1-4), such as L n The sum of the values ​​(i.e., L1+L2+L3+...+L K ) may include a maximum value of

[0399] Referring to FIG. 12, a base station transmits channel state information (CSI) and related configuration information to a UE (S1201).

[0400] The configuration information related to the CSI may include at least one of CSI-IM (interference management) resource configuration information, CSI measurement configuration information, CSI resource configuration information, and CSI report configuration information.

[0401] In addition, the configuration information related to the CSI (particularly, for example, configuration information related to CSI reporting) may include information regarding the proposed method described above (for example, any one or a combination of one or more of Examples 1-1, 1-2, 1-3, and 1-4).

[0402] For example, according to the above-mentioned embodiment 1-1, the setting information includes: i) one or more first parameters (L n ,n=1,...,N TRP ii) information about the combination of the second parameter (p) and the third parameter (beta).

[0403] For example, according to the above-mentioned embodiment 1-2, the setting information includes one or more first parameters (L n ,n=1,...,N TRP ) and may include information about one or more first parameters (L n ,n=1,...,N TRP ) and information about the combination of the second parameter (p) and the third parameter (beta).

[0404] For example, in the above-described embodiments 1-3, the setting information may include one or more pieces of information for a combination of the first parameter (L), the second parameter (p), and the third parameter (beta). When a plurality of second parameters (p) and a plurality of third parameters (beta) are set, each of the second parameters (p) and the third parameter (beta) may be determined as a representative value.

[0405] For example, according to the above-described embodiments 1-4, the configuration information (e.g., configuration information related to CSI resources) is set to K (= the number of TRPs, i.e., N TRP ) CSI-RS resources. In this case, the K value may define separate / different configurable parameter combinations for L, p, and beta. For example, in combination with Example 1-1, L n (n=1,...,N TRP ) value and p, beta combinations are signaled separately, L n(n=1,...,N TRP ) value and combinations of p and beta. That is, the UE may define a configurable parameter combination between L n (n=1,...,N TRP ) value and the combination of p and beta can be assumed to be signaled.

[0406] The base station transmits CSI-RS to the UE on one or more (ie, K, where K is a natural number) CSI-RS resources (S1202).

[0407] Here, the base station can transmit the CSI-RS through one or more antenna ports on one or more CSI-RS resources based on the configuration information.

[0408] The base station receives channel state information (CSI) (feedback / report) from the UE (S1203).

[0409] Here, the channel state information (CSI) (feedback / report) may be received on an uplink physical layer channel (e.g., PUCCH or PUSCH), and the CSI may include at least one of PMI, CQI, RI, and LI.

[0410] The CSI received from the UE may be derived / generated based on the proposed method described above (for example, any one or a combination of one or more of Examples 1-1, 1-2, 1-3, and 1-4).

[0411] For example, the CSI may include a PMI corresponding to an index of a codebook for indicating a precoding matrix. Here, the codebook may correspond to a codebook based on a linear combination of SD basis vectors and FD basis vectors as illustrated in FIG. 9, and the type of the codebook may be, for example, a Type II CJT (coherent joint transmission) codebook.

[0412] The precoding matrix indicated by the PMI may be determined from the plurality of vectors. In other words, the precoding matrix indicated by the PMI is determined by the L n (i.e., the number of SD basis vectors) vectors + M (i.e., the number of FD basis vectors, where M is M for each layer) υ may be denoted as: . ) vector.

[0413] The K CSI-RS resources may correspond to different TRPs. That is, each CSI-RS resource may correspond to a different TRP. Here, the UE may select N (1≦N≦K) CSI-RS resources from the configured K CSI-RS resources, calculate / derive PMI values ​​for the N (1≦N≦K) CSI-RS resources, and report them to the base station. In this case, the precoding matrix indicated by the PMI may be determined from vectors (i.e., SD basis vectors) corresponding to the selected N CSI-RS resources and M vectors (i.e., FD basis vectors).

[0414] The number of the plurality of vectors (i.e., the number of SD basis vectors and the number of FD basis vectors) is determined by the one or more first parameters (L n ,n=1,...,N TRP ) and the second parameter (p). n ,n=1,...,N TRP ) may correspond one-to-one to the K CSI-RS resources. n ,n=1,...,N TRP ) may indicate the number of SD basis vectors associated with the corresponding CSI-RS resource. Here, when the UE calculates / derives PMI values ​​for N (1≦N≦K) CSI-RS resources and reports them to the base station, one or more first parameters (L n ,n=1,...,NTRP ) may be used. Also, the number of FD basis vectors common to the K CSI-RS resources (or common to the N CSI-RS resources selected by the UE) may be determined using the second parameter (p).

[0415] As described above, the PMI corresponds to codebook indexes i1 and i2. i1 and i2 may each be composed of a plurality of codebook indexes according to the rank number (v). The codebook index may include various indexes, and in particular, an amplitude coefficient indicator (e.g., i 2,4,l (l=1,...,υ)) and a phase coefficient indicator (e.g., i 2,5,l (l=1,...,v)). The codebook index may also include a bitmap for identifying which coefficients are reported by the amplitude coefficient indicator and the phase coefficient indicator (i.e., a bitmap for indicating non-zero coefficients among one or more amplitude coefficients and one or more phase coefficients) (e.g., i 1,7,l (l=1,...,v)), where the upper bound of the non-zero coefficients in the amplitude coefficient and the phase coefficient (i.e., the non-zero coefficients do not differ from the upper bound) is determined by the one or more first parameters (L n ,n=1,...,N TRP ), the second parameter (p), and the third parameter (beta).

[0416] [Table 18]

[0417] General devices to which the present disclosure can be applied FIG. 13 is a block diagram illustrating a wireless communication device according to an embodiment of the present disclosure.

[0418] Referring to FIG. 13, a first wireless device 100 and a second wireless device 200 can transmit and receive wireless signals using various wireless access technologies (e.g., LTE, NR).

[0419] The first wireless device 100 includes one or more processors 102 and one or more memories 104, and may further include one or more transceivers 106 and / or one or more antennas 108. The processor 102 may be configured to control the memory 104 and / or the transceiver 106 to implement the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed in this disclosure. For example, the processor 102 may process information in the memory 104 to generate first information / signal and then transmit a wireless signal including the first information / signal from the transceiver 106. The processor 102 may also receive a wireless signal including second information / signal from the transceiver 106 and then store information obtained from signal processing of the second information / signal in the memory 104. The memory 104 may be coupled to the processor 102 and may store various information related to the operation of the processor 102. For example, the memory 104 may store software code including instructions for performing some or all of the processes controlled by the processor 102 or for implementing the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed in this disclosure. Here, the processor 102 and the memory 104 may be part of a communications modem / circuit / chip designed to implement a wireless communication technology (e.g., LTE, NR). The transceiver 106 may be coupled to the processor 102 and may transmit and / or receive wireless signals via one or more antennas 108. The transceiver 106 may include a transmitter and / or a receiver. The transceiver 106 may also be referred to as an RF (Radio Frequency) unit. In the present invention, a wireless device may refer to a communications modem / circuit / chip.

[0420] The second wireless device 200 includes one or more processors 202, one or more memories 204, and may further include one or more transceivers 206 and / or one or more antennas 208. The processor 202 may be configured to control the memory 204 and / or the transceiver 206 to implement the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed in this disclosure. For example, the processor 202 may process information in the memory 204 to generate third information / signal, and then transmit a wireless signal including the third information / signal from the transceiver 206. The processor 202 may also receive a wireless signal including fourth information / signal from the transceiver 206, and then store information obtained from signal processing of the fourth information / signal in the memory 204. The memory 204 may be coupled to the processor 202 and may store various information related to the operation of the processor 202. For example, the memory 204 may store software code including instructions for performing some or all of the processes controlled by the processor 202 or for implementing the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed in this disclosure. Here, the processor 202 and the memory 204 may be part of a communications modem / circuit / chip designed to implement a wireless communication technology (e.g., LTE, NR). The transceiver 206 may be coupled to the processor 202 and may transmit and / or receive wireless signals via one or more antennas 208. The transceiver 206 may include a transmitter and / or a receiver. The transceiver 206 may also be referred to as an RF unit. In the present invention, a wireless device may refer to a communications modem / circuit / chip.

[0421] The hardware elements of the wireless devices 100, 200 are described in more detail below. Without limitation, one or more protocol layers may be implemented by one or more processors 102, 202. For example, one or more processors 102, 202 may implement one or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP, RRC, and SDAP). The one or more processors 102, 202 may generate one or more protocol data units (PDUs) and / or one or more service data units (SDUs) according to the descriptions, functions, procedures, suggestions, methods, and / or operational flow diagrams disclosed in this disclosure. The one or more processors 102, 202 may generate messages, control information, data, or information according to the descriptions, functions, procedures, suggestions, methods, and / or operational flow diagrams disclosed in this disclosure. The one or more processors 102, 202 can generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data, or information according to the functions, procedures, suggestions, and / or methods disclosed in this disclosure and provide them to the one or more transceivers 106, 206. The one or more processors 102, 202 can receive signals (e.g., baseband signals) from the one or more transceivers 106, 206 and obtain the PDUs, SDUs, messages, control information, data, or information according to the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed in this disclosure.

[0422] The one or more processors 102, 202 may be referred to as a controller, microcontroller, microprocessor, or microcomputer. The one or more processors 102, 202 may be implemented using hardware, firmware, software, or a combination thereof. As an example, the one or more processors 102, 202 may include one or more application-specific integrated circuits (ASICs), one or more digital signal processors (DSPs), one or more digital signal processing devices (DSPDs), one or more programmable logic devices (PLDs), or one or more field programmable gate arrays (FPGAs). The descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed in this disclosure may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, etc. Firmware or software configured to execute the descriptions, functions, procedures, suggestions, methods, and / or operational flow diagrams disclosed in this disclosure may be included in one or more processors 102, 202 or stored in one or more memories 104, 204 and executed by one or more processors 102, 202. The descriptions, functions, procedures, suggestions, methods, and / or operational flow diagrams disclosed in this disclosure may be embodied by firmware or software in the form of code, instructions, and / or collections of instructions.

[0423] One or more memories 104, 204 may be coupled to one or more processors 102, 202 and may store various types of data, signals, messages, information, programs, code, instructions, and / or instructions. The one or more memories 104, 204 may be comprised of ROM, RAM, EPROM, flash memory, hard drives, registers, cache memory, computer-readable storage media, and / or combinations thereof. The one or more memories 104, 204 may be located internal and / or external to the one or more processors 102, 202. Additionally, the one or more memories 104, 204 may be coupled to the one or more processors 102, 202 via various techniques, such as wired or wireless connections.

[0424] One or more transceivers 106, 206 may transmit user data, control information, wireless signals / channels, etc., as referred to in the methods and / or operational flowcharts of the present disclosure, to one or more other devices. One or more transceivers 106, 206 may receive user data, control information, wireless signals / channels, etc., as referred to in the descriptions, functions, procedures, suggestions, methods and / or operational flowcharts of the present disclosure, from one or more other devices. For example, one or more transceivers 106, 206 may be coupled to one or more processors 102, 202 and may transmit and receive wireless signals. For example, one or more processors 102, 202 may control one or more transceivers 106, 206 to transmit user data, control information, or wireless signals to one or more other devices. Also, one or more processors 102, 202 may control one or more transceivers 106, 206 to receive user data, control information, or wireless signals from one or more other devices. Furthermore, one or more transceivers 106, 206 may be coupled to one or more antennas 108, 208, and the one or more transceivers 106, 206 may be configured to transmit and receive user data, control information, wireless signals / channels, etc., referred to in the descriptions, functions, procedures, suggestions, methods, and / or operational flowcharts disclosed in this disclosure, via the one or more antennas 108, 208. In this disclosure, the one or more antennas may be multiple physical antennas or multiple logical antennas (e.g., antenna ports). The one or more transceivers 106, 206 may convert the received user data, control information, wireless signals / channels, etc., from RF band signals to baseband signals for processing using one or more processors 102, 202. The one or more transceivers 106, 206 may convert the user data, control information, wireless signals / channels, etc., processed using one or more processors 102, 202, from baseband signals to RF band signals. To that end, one or more of the transceivers 106, 206 may include (analog) oscillators and / or filters.

[0425] The embodiments described above are combinations of the components and features of the present disclosure in a predetermined form. Each component or feature should be considered optional unless otherwise explicitly stated. Each component or feature may be implemented without being combined with other components or features. It is also possible to combine some components and / or features to form embodiments of the present disclosure. The order of operations described in the embodiments of the present disclosure may be changed. Some components or features of one embodiment may be included in another embodiment, or may be replaced with corresponding components or features of another embodiment. It is clear that claims that do not have an explicit reference relationship in the claims may be combined to form embodiments, or may be included as new claims by amendment after filing.

[0426] It is obvious to those skilled in the art that the present disclosure can be embodied in other specific forms without departing from the essential features of the present disclosure. Therefore, the above detailed description should not be interpreted as limiting in any respect, but should be considered as illustrative. The scope of the present disclosure should be determined by reasonable interpretation of the appended claims, and any modifications within the equivalent scope of the present disclosure are included in the scope of the present disclosure.

[0427] The scope of the present disclosure includes software or machine-executable instructions (e.g., operating systems, applications, firmware, programs, etc.) that cause a device or computer to perform operations according to the methods of various embodiments, as well as non-transitory computer-readable media on which such software or instructions are stored and executable on a device or computer. Instructions usable for programming a processing system to perform features described in this disclosure may be stored on or in a storage medium or computer-readable storage medium, and computer program products including such storage media may be used to embody features described in this disclosure. The storage medium may include, but is not limited to, high-speed random access memory such as DRAM, SRAM, DDR RAM, or other random access solid-state memory devices, and may include non-volatile memory such as one or more magnetic disk storage devices, optical disk storage devices, flash memory devices, or other non-volatile solid-state storage devices. Memory optionally includes one or more storage devices located remotely from the processor. The memory, or alternatively, a non-volatile memory device within the memory, comprises a non-transitory computer-readable storage medium. The features described in this disclosure may be embodied in software and / or firmware stored on any one of a number of machine-readable media and capable of controlling the hardware of a processing system and allowing the processing system to interact with other mechanisms that utilize the results of embodiments of the present disclosure. Such software or firmware may include, but is not limited to, application code, device drivers, operating systems, and execution environments / containers.

[0428] Here, the wireless communication technology implemented in the wireless devices 100 and 200 of the present disclosure may include LTE, NR, 6G, and also Narrowband Internet of Things (NB-IoT) for low-power communication. Here, for example, the NB-IoT technology may be an example of a Low Power Wide Area Network (LPWAN) technology and may be implemented according to standards such as LTE Cat NB1 and / or LTE Cat NB2, and is not limited to the above-mentioned names. Additionally or alternatively, the wireless communication technology implemented in the wireless devices 100 and 200 of the present disclosure may perform communication based on the LTE-M technology. Here, for example, the LTE-M technology may be an example of an LPWAN technology and may be referred to by various names such as enhanced Machine Type Communication (eMTC). For example, LTE-M technology may be implemented by at least one of various standards such as 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-BL (non-Bandwidth Limited), 5) LTE-MTC, 6) LTE Machine Type Communication, and / or 7) LTE M, and is not limited to the above names. Additionally or alternatively, wireless communication technologies implemented in wireless devices 100 and 200 of the present disclosure may include at least one of ZigBee, Bluetooth (registered trademark), and Low Power Wide Area Network (LPWAN), which consider low-power communication, and are not limited to the above names. As an example, ZigBee technology can create personal area networks (PANs) related to small / low-power digital communication based on various standards such as IEEE 802.15.4, and may be referred to by various names. [Industrial Applicability]

[0429] The method proposed in this disclosure has been described mainly as being applied to 3GPP LTE / LTE-A and 5G systems, but it can also be applied to various other wireless communication systems in addition to 3GPP LTE / LTE-A and 5G systems.

[0430] [Claims at the time of international application] [Claim 1] 1. A method performed by a user equipment (UE) in a wireless communication system, comprising: receiving a channel state information (CSI) report and associated configuration information from a base station; receiving CSI-reference signal (CSI-RS) from the base station on K CSI-RS resources (K is a natural number); and transmitting CSI to the base station; The CSI includes a precoding matrix indicator (PMI) corresponding to a codebook index; The setting information is i) first information for one or more first parameters; and ii) second information for a combination of the second parameter and the third parameter; The precoding matrix indicated by the PMI is determined from a plurality of vectors; the number of the plurality of vectors is determined based on the one or more first parameters and the second parameter; the codebook index includes an amplitude coefficient indicator indicating one or more amplitude coefficients and a phase coefficient indicator indicating one or more phase coefficients; an upper bound of the total number of non-zero coefficients in the one or more amplitude coefficients and the one or more phase coefficients is determined based on the one or more first parameters, the second parameter, and the third parameter; configurable combinations of i) the one or more first parameters and ii) combinations of the second and third parameters are determined independently by the number of the K CSI-RS resources. [Claim 2] The method of claim 1 , wherein each of the one or more first parameters corresponds one-to-one to the K CSI-RS resources. [Claim 3] The method of claim 1 , wherein the PMI is a value for N (1≦N≦K) CSI-RS resources selected by the UE from among the K CSI-RS resources. [Claim 4] 4. The method of claim 3, wherein a first parameter corresponding to the N CSI-RS resources is utilized to determine an upper bound on a total number of the plurality of vectors and non-zero coefficients. [Claim 5] 3. The method of claim 2, wherein each of the one or more first parameters indicates a number of spatial domain basis vectors associated with a corresponding CSI-RS resource. [Claim 6] The method of claim 2 , wherein the second parameter is used to determine a number of frequency-domain basis vectors common to the K CSI-RS resources. [Claim 7] 3. The method of claim 2, wherein an upper bound on the total number of non-zero coefficients is determined to be the smallest integer not less than the sum of the one or more first parameters, the second parameter, and all products of the third parameter. [Claim 8] The method of claim 1 , wherein the type of the codebook is a Type II coherent joint transmission (CJT) codebook. [Claim 9] A user equipment (UE) operating in a wireless communication system, comprising: one or more transceivers for transmitting and receiving radio signals; one or more processors that control the one or more transceivers; the one or more processors: receiving channel state information (CSI) reports and associated configuration information from a base station; receiving CSI-reference signal (CSI-RS) from the base station on K CSI-RS resources (K is a natural number); and transmitting CSI to the base station; The CSI includes a precoding matrix indicator (PMI) corresponding to a codebook index; The setting information is i) first information for one or more first parameters; and ii) second information for a combination of the second parameter and the third parameter; The precoding matrix indicated by the PMI is determined from a plurality of vectors; the number of the plurality of vectors is determined based on the one or more first parameters and the second parameter; the codebook index includes an amplitude coefficient indicator indicating one or more amplitude coefficients and a phase coefficient indicator indicating one or more phase coefficients; an upper bound of the total number of non-zero coefficients in the one or more amplitude coefficients and the one or more phase coefficients is determined based on the one or more first parameters, the second parameter, and the third parameter; A user equipment, wherein configurable combinations of i) the one or more first parameters and ii) combinations of the second and third parameters are individually determined by the number of the K CSI-RS resources. [Claim 10] one or more non-transitory computer-readable media storing one or more instructions, The at least one or more instructions executable by at least one processor control a user equipment (UE); The instruction: receiving a channel state information (CSI) report and associated configuration information from a base station; receiving CSI-reference signal (CSI-RS) from the base station on K CSI-RS resources (K is a natural number); and transmitting the CSI to the base station; The CSI is controlled to include a precoding matrix indicator (PMI) corresponding to a codebook index; the setting information includes: i) first information for one or more first parameters; and ii) second information for a combination of a second parameter and a third parameter; The precoding matrix indicated by the PMI is determined from a plurality of vectors; the number of the plurality of vectors is determined based on the one or more first parameters and the second parameter; the codebook index includes an amplitude coefficient indicator indicating one or more amplitude coefficients and a phase coefficient indicator indicating one or more phase coefficients; an upper bound of the total number of non-zero coefficients in the one or more amplitude coefficients and the one or more phase coefficients is determined based on the one or more first parameters, the second parameter, and the third parameter; a non-transitory computer-readable medium, wherein configurable combinations of i) the one or more first parameters and ii) combinations of the second and third parameters are independently determined by the number of the K CSI-RS resources. [Claim 11] 1. A processing device configured to control a user equipment (UE) in a wireless communication system, comprising: one or more processors; one or more computer memories operably coupled to the one or more processors and storing instructions that perform operations upon being executed by the one or more processors; The operation is receiving channel state information (CSI) reports and associated configuration information from a base station; receiving CSI-reference signal (CSI-RS) from the base station on K CSI-RS resources (K is a natural number); and transmitting CSI to the base station; The CSI includes a precoding matrix indicator (PMI) corresponding to a codebook index; the setting information includes: i) first information for one or more first parameters; and ii) second information for a combination of a second parameter and a third parameter; The precoding matrix indicated by the PMI is determined from a plurality of vectors; the number of the plurality of vectors is determined based on the one or more first parameters and the second parameter; the codebook index includes an amplitude coefficient indicator indicating one or more amplitude coefficients and a phase coefficient indicator indicating one or more phase coefficients; an upper bound of the total number of non-zero coefficients in the one or more amplitude coefficients and the one or more phase coefficients is determined based on the one or more first parameters, the second parameter, and the third parameter; A processing device, wherein configurable combinations of i) the one or more first parameters and ii) combinations of the second and third parameters are individually determined depending on the number of the K CSI-RS resources. [Claim 12] 1. A method performed by a base station in a wireless communication system, comprising: transmitting a channel state information (CSI) report and associated configuration information to a user equipment (UE); transmitting CSI-reference signal (CSI-RS) to the UE on K CSI-RS resources (K is a natural number); and receiving CSI from the UE; The CSI includes a precoding matrix indicator (PMI) corresponding to a codebook index; the setting information includes: i) first information for one or more first parameters; and ii) second information for a combination of a second parameter and a third parameter; The precoding matrix indicated by the PMI is determined from a plurality of vectors; the number of the plurality of vectors is determined based on the one or more first parameters and the second parameter; the codebook index includes an amplitude coefficient indicator indicating one or more amplitude coefficients and a phase coefficient indicator indicating one or more phase coefficients; an upper bound of the total number of non-zero coefficients in the one or more amplitude coefficients and the one or more phase coefficients is determined based on the one or more first parameters, the second parameter, and the third parameter; configurable combinations of i) the one or more first parameters and ii) combinations of the second and third parameters are determined independently by the number of the K CSI-RS resources. [Claim 13] 1. A base station operating in a wireless communication system, comprising: one or more transceivers for transmitting and receiving radio signals; one or more processors that control the one or more transceivers; the one or more processors: Transmitting channel state information (CSI) reports and related configuration information to a user equipment (UE); transmitting CSI-reference signal (CSI-RS) to the UE on K CSI-RS resources (K is a natural number); receiving CSI from the UE; The CSI includes a precoding matrix indicator (PMI) corresponding to a codebook index; the setting information includes: i) first information for one or more first parameters; and ii) second information for a combination of a second parameter and a third parameter; The precoding matrix indicated by the PMI is determined from a plurality of vectors; the number of the plurality of vectors is determined based on the one or more first parameters and the second parameter; the codebook index includes an amplitude coefficient indicator indicating one or more amplitude coefficients and a phase coefficient indicator indicating one or more phase coefficients; an upper bound of the total number of non-zero coefficients in the one or more amplitude coefficients and the one or more phase coefficients is determined based on the one or more first parameters, the second parameter, and the third parameter; A base station, wherein configurable combinations of i) the one or more first parameters and ii) combinations of the second and third parameters are individually determined depending on the number of the K CSI-RS resources.

Claims

1. 1. A method performed by a user equipment (UE) in a wireless communication system, comprising: receiving a channel state information (CSI) report and associated configuration information from a base station; Receiving CSI-reference signal (CSI-RS) from the base station on K CSI-RS resources (K is a natural number); and transmitting CSI to the base station; The CSI includes a precoding matrix indicator (PMI) corresponding to a codebook index; The setting information is i) first information for one or more first parameters; and ii) second information for a combination of the second parameter and the third parameter; The precoding matrix indicated by the PMI is determined from a plurality of vectors; the number of the plurality of vectors is determined based on the one or more first parameters and the second parameter; the codebook index includes an amplitude coefficient indicator indicating one or more amplitude coefficients and a phase coefficient indicator indicating one or more phase coefficients; an upper bound of a total number of non-zero coefficients in the one or more amplitude coefficients and the one or more phase coefficients is determined based on the one or more first parameters, the second parameter, and the third parameter; A method in which configurable combinations of i) the one or more first parameters and ii) combinations of the second and third parameters are determined individually depending on the number of the K CSI-RS resources.

2. The method of claim 1 , wherein each of the one or more first parameters corresponds one-to-one to the K CSI-RS resources.

3. The method of claim 1, wherein the PMI is a value for N (1≦N≦K) CSI-RS resources selected by the UE from among the K CSI-RS resources.

4. The method of claim 3 , wherein a first parameter corresponding to the N CSI-RS resources is used to determine an upper bound on a total number of the plurality of vectors and non-zero coefficients.

5. The method of claim 2 , wherein each of the one or more first parameters indicates a number of spatial domain basis vectors associated with a corresponding CSI-RS resource.

6. The method of claim 2 , wherein the second parameter is used to determine a number of frequency-domain basis vectors common to the K CSI-RS resources.

7. 3. The method of claim 2, wherein an upper bound on the total number of non-zero coefficients is determined to be the smallest integer not less than the sum of the one or more first parameters, the second parameter, and all products of the third parameter.

8. The method of claim 1 , wherein the type of the codebook is a type II coherent joint transmission (CJT) codebook.

9. 1. A user equipment (UE) operating in a wireless communication system, comprising: one or more transceivers for transmitting and receiving radio signals; one or more processors that control the one or more transceivers; The one or more processors: receiving a channel state information (CSI) report and associated configuration information from a base station; receiving CSI-reference signal (CSI-RS) from the base station on K CSI-RS resources (K is a natural number); and transmitting CSI to the base station; The CSI includes a precoding matrix indicator (PMI) corresponding to a codebook index; The setting information is i) first information for one or more first parameters; and ii) second information for a combination of the second parameter and the third parameter; The precoding matrix indicated by the PMI is determined from a plurality of vectors; the number of the plurality of vectors is determined based on the one or more first parameters and the second parameter; the codebook index includes an amplitude coefficient indicator indicating one or more amplitude coefficients and a phase coefficient indicator indicating one or more phase coefficients; an upper bound of a total number of non-zero coefficients in the one or more amplitude coefficients and the one or more phase coefficients is determined based on the one or more first parameters, the second parameter, and the third parameter; A user equipment, wherein configurable combinations of i) the one or more first parameters and ii) the combinations of the second and third parameters are individually determined depending on the number of the K CSI-RS resources.

10. one or more non-transitory computer-readable media storing one or more instructions, The at least one or more instructions executable by at least one processor control user equipment (UE); The instruction: receiving a channel state information (CSI) report and associated configuration information from a base station; Receiving CSI-reference signal (CSI-RS) from the base station on K CSI-RS resources (K is a natural number); and transmitting the CSI to the base station; The CSI is controlled to include a precoding matrix indicator (PMI) corresponding to a codebook index; the setting information includes: i) first information for one or more first parameters; and ii) second information for a combination of a second parameter and a third parameter; The precoding matrix indicated by the PMI is determined from a plurality of vectors; the number of the plurality of vectors is determined based on the one or more first parameters and the second parameter; the codebook index includes an amplitude coefficient indicator indicating one or more amplitude coefficients and a phase coefficient indicator indicating one or more phase coefficients; an upper bound of a total number of non-zero coefficients in the one or more amplitude coefficients and the one or more phase coefficients is determined based on the one or more first parameters, the second parameter, and the third parameter; a non-transitory computer-readable medium, wherein configurable combinations of i) the one or more first parameters and ii) combinations of the second and third parameters are independently determined by the number of the K CSI-RS resources.

11. 1. A processing device configured to control user equipment (UE) in a wireless communication system, comprising: one or more processors; one or more computer memories operably coupled to the one or more processors and storing instructions for performing operations based on being executed by the one or more processors; The operation is receiving a channel state information (CSI) report and associated configuration information from a base station; receiving CSI-reference signal (CSI-RS) from the base station on K CSI-RS resources (K is a natural number); and transmitting CSI to the base station; The CSI includes a precoding matrix indicator (PMI) corresponding to a codebook index; the setting information includes: i) first information for one or more first parameters; and ii) second information for a combination of a second parameter and a third parameter; The precoding matrix indicated by the PMI is determined from a plurality of vectors; the number of the plurality of vectors is determined based on the one or more first parameters and the second parameter; the codebook index includes an amplitude coefficient indicator indicating one or more amplitude coefficients and a phase coefficient indicator indicating one or more phase coefficients; an upper bound of a total number of non-zero coefficients in the one or more amplitude coefficients and the one or more phase coefficients is determined based on the one or more first parameters, the second parameter, and the third parameter; A processing device, wherein configurable combinations of i) the one or more first parameters and ii) the combinations of the second and third parameters are individually determined depending on the number of the K CSI-RS resources.

12. 1. A method performed by a base station in a wireless communication system, comprising: transmitting channel state information (CSI) reports and associated configuration information to a user equipment (UE); Transmitting CSI-reference signal (CSI-RS) to the UE on K CSI-RS resources (K is a natural number); and receiving CSI from the UE; The CSI includes a precoding matrix indicator (PMI) corresponding to a codebook index; the setting information includes: i) first information for one or more first parameters; and ii) second information for a combination of a second parameter and a third parameter; The precoding matrix indicated by the PMI is determined from a plurality of vectors; the number of the plurality of vectors is determined based on the one or more first parameters and the second parameter; the codebook index includes an amplitude coefficient indicator indicating one or more amplitude coefficients and a phase coefficient indicator indicating one or more phase coefficients; an upper bound of a total number of non-zero coefficients in the one or more amplitude coefficients and the one or more phase coefficients is determined based on the one or more first parameters, the second parameter, and the third parameter; A method in which configurable combinations of i) the one or more first parameters and ii) combinations of the second and third parameters are determined individually depending on the number of the K CSI-RS resources.

13. 1. A base station operating in a wireless communication system, comprising: one or more transceivers for transmitting and receiving radio signals; one or more processors that control the one or more transceivers; The one or more processors: Sending channel state information (CSI) reports and related configuration information to a user equipment (UE); Transmitting CSI-reference signal (CSI-RS) to the UE on K CSI-RS resources (K is a natural number); receiving CSI from the UE; The CSI includes a precoding matrix indicator (PMI) corresponding to a codebook index; the setting information includes: i) first information for one or more first parameters; and ii) second information for a combination of a second parameter and a third parameter; The precoding matrix indicated by the PMI is determined from a plurality of vectors; the number of the plurality of vectors is determined based on the one or more first parameters and the second parameter; the codebook index includes an amplitude coefficient indicator indicating one or more amplitude coefficients and a phase coefficient indicator indicating one or more phase coefficients; an upper bound of a total number of non-zero coefficients in the one or more amplitude coefficients and the one or more phase coefficients is determined based on the one or more first parameters, the second parameter, and the third parameter; A base station, wherein configurable combinations of i) the one or more first parameters and ii) the combinations of the second and third parameters are individually determined depending on the number of the K CSI-RS resources.

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