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

Abstract

A method and an apparatus for transmitting or receiving channel state information in a wireless communication system are disclosed. A method performed by a terminal in a wireless communication system according to an embodiment disclosed herein may comprise the steps of: receiving one or more channel state information-reference signals (CSI-RS) from a network; calculating a channel quality indicator (CQI) based on a specific precoding matrix indicator (PMI), wherein the specific precoding matrix indicator is one of a plurality of PMIs respectively corresponding to the plurality of time units; and transmitting a CSI report to the network, the CSI report including one CQI and codebook information corresponding to the plurality of PMIs, where the one CQI may be associated with a specific PMI and a specific time unit that is one of the plurality of time units.

Description

Technical Field

[0001] The present disclosure relates to a wireless communication system, and more particularly, to a method and apparatus for sending or receiving channel state information in a wireless communication system. Background Art

[0002] A mobile communication system has been developed to provide voice services while ensuring user mobility. However, the mobile communication system has been extended to data services as well as voice services, and currently, the explosive growth of services has led to resource shortages, and users have demanded faster services, thus requiring more advanced mobile communication systems.

[0003] The overall requirement for the next generation mobile communication system should be able to support the accommodation of explosive data services, a significant increase in the transmission rate per user, the accommodation of a significantly increased number of connected devices, very low end-to-end latency and high energy efficiency. To this end, a variety of technologies such as dual connectivity, massive multiple-input multiple-output (massive MIMO), in-band full-duplex, non-orthogonal multiple access (NOMA), ultra-wideband support, and device networking have been studied. Summary of the invention

[0004] Technical goals

[0005] The technical problem of the present disclosure is to provide a method and apparatus for sending or receiving channel state information (CSI) in a wireless communication system.

[0006] An additional technical problem of the present disclosure is to provide a method and apparatus for transmitting or receiving a CSI report including a codebook corresponding to precoding matrix indication information for a plurality of time units in a wireless communication system.

[0007] The technical objectives to be achieved by the present disclosure are not limited to the above-mentioned technical objectives, and those skilled in the art can clearly understand other technical objectives not described herein through the following description.

[0008] Technical Solution

[0009] According to one aspect of the present disclosure, a method performed by a terminal in a wireless communication system includes: receiving at least one channel state information-reference signal (CSI-RS) from a network; calculating a channel quality indicator (CQI) based on a specific precoding matrix indicator (PMI), wherein the specific precoding matrix indicator (PMI) is one of multiple PMIs corresponding to multiple time units respectively; and sending a CSI report to the network, the CSI report including the one CQI and codebook information corresponding to the multiple PMIs, wherein the one CQI can be associated with the specific PMI and a specific time unit that is one of the multiple time units.

[0010] According to additional aspects of the present disclosure, a method performed by a base station in a wireless communication system includes: sending at least one channel state information-reference signal (CSI-RS) to a terminal; and receiving a CSI report from the terminal, the CSI report including a channel quality indicator (CQI) and codebook information corresponding to multiple precoding matrix indicators (PMIs), wherein the one CQI can be calculated based on a specific PMI, the specific PMI is one of multiple PMIs corresponding to multiple time units respectively, and the one CQI can be associated with the specific PMI and the specific time unit as one of the multiple time units.

[0011] Technical Effects

[0012] According to the present disclosure, a method and apparatus for transmitting or receiving channel state information (CSI) in a wireless communication system may be provided.

[0013] According to an embodiment of the present disclosure, a method and apparatus for sending or receiving a CSI report in a wireless communication system may be provided, where the CSI report includes a codebook corresponding to precoding matrix indication information for a plurality of time units.

[0014] Effects achievable by the present disclosure are not limited to the above-described effects, and other effects not described herein may be clearly understood by those skilled in the art through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] The accompanying drawings, which are included as a part of the detailed description for understanding the present disclosure, provide embodiments of the present disclosure and describe technical features of the present disclosure through the detailed description.

[0016] Figure 1 The structure of a wireless communication system to which the present disclosure can be applied is illustrated.

[0017] Figure 2 The frame structure in a wireless communication system to which the present disclosure can be applied is illustrated.

[0018] Figure 3 A resource grid in a wireless communication system to which the present disclosure can be applied is illustrated.

[0019] Figure 4 The physical resource blocks in a wireless communication system to which the present disclosure can be applied are illustrated.

[0020] Figure 5 The time slot structure in a wireless communication system to which the present disclosure can be applied is illustrated.

[0021] Figure 6 Physical channels used in a wireless communication system to which the present disclosure can be applied and a general signal transmission and reception method using the physical channels are illustrated.

[0022] Figure 7 A method for sending multiple TRPs in a wireless communication system to which the present disclosure can be applied is illustrated.

[0023] Figure 8 is a diagram for describing an example of a CSI report transmission method of a terminal according to the present disclosure.

[0024] Fig. 9 is a diagram for describing an example of a CSI report receiving method of a base station according to the present disclosure.

[0025] Fig.10 and Fig.11 is a diagram for describing an example of a CSI reference resource and a CSI reporting time unit according to the present disclosure.

[0026] Fig.12 A block diagram of a wireless communication device according to an embodiment of the present disclosure is illustrated. DETAILED DESCRIPTION

[0027] Hereinafter, embodiments according to the present disclosure will be described in detail with reference to the accompanying drawings. The detailed description disclosed by the accompanying drawings is intended to describe exemplary embodiments of the present disclosure, rather than to represent the only embodiment in which the present disclosure can be implemented. The following detailed description includes specific details to provide a complete understanding of the present disclosure. However, those skilled in the relevant art know that the present disclosure can be implemented without these specific details.

[0028] In some cases, well-known structures and devices may be omitted, or may be shown in the form of a block diagram based on the core functions of each structure and device in order to prevent ambiguity in the concepts of the present disclosure.

[0029] In the present disclosure, when an element is referred to as being "connected", "combined" or "linked" to another element, it may include an indirect connection relationship between another element and a direct connection relationship. In addition, in the present disclosure, the term "comprising" or "having" specifies the presence of the mentioned features, steps, operations, components and / or elements, but does not exclude the presence or addition of one or more other features, stages, operations, components, elements and / or groups thereof.

[0030] In the present disclosure, terms such as "first", "second", etc. are only used to distinguish one element from another element and are not used to limit the elements, and unless otherwise specified, they do not limit the order or importance between elements, etc. Therefore, within the scope of the present disclosure, the first element in an embodiment may be referred to as the second element in another embodiment, and similarly, the second element in an embodiment may be referred to as the first element in another embodiment.

[0031] The terms used in this disclosure are intended to describe specific embodiments, rather than to limit the claims. As used in the description of the embodiments and the appended claims, the singular form is intended to include the plural form, unless the context clearly indicates otherwise. The term "and / or" used in this disclosure may refer to one of the related enumerated items, or mean that it refers to and includes any and all possible combinations of two or more of them. In addition, unless otherwise stated, the " / " between words in this disclosure has the same meaning as "and / or".

[0032] The present disclosure describes a wireless communication network or a wireless communication system, and operations performed in the wireless communication network can be performed in a process in which a device (e.g., a base station) that controls the corresponding wireless communication network controls the network and sends or receives signals, or can be performed in a process in which a terminal associated with the corresponding wireless network sends or receives signals between the network or the terminal.

[0033] In the present disclosure, sending or receiving a channel includes the meaning of sending or receiving information or signals through the corresponding channel. For example, sending a control channel means sending control information or control signals through the control channel. Similarly, sending a data channel means sending data information or data signals through the data channel.

[0034] In the following, downlink (DL) means communication from a base station to a terminal, and uplink (UL) means communication from a terminal to a base station. In the downlink, the transmitter may be part of a base station, and the receiver may be part of a terminal. In the uplink, the transmitter may be part of a terminal, and the receiver may be part of a base station. The base station may be expressed as a first communication device, and the terminal may be expressed as a second communication device. The base station (BS) may be replaced by terms such as a fixed station, a node B, an eNB (evolved node B), a gNB (next generation node B), a BTS (base station transceiver system), an access point (AP), a network (5G network), an AI (artificial intelligence) system / module, an RSU (roadside unit), a robot, a drone (UAV: unmanned aerial vehicle), an AR (augmented reality) device, a VR (virtual reality) device, and the like. In addition, the terminal can be fixed or mobile, and can be replaced by 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 (roadside unit), robot, AI (artificial intelligence) module, drone (UAV: unmanned aerial vehicle), AR (augmented reality) device, VR (virtual reality) device, etc.

[0035] The following description can be used for various radio access systems, such as CDMA, FDMA, TDMA, OFDMA, SC-FDMA, etc. CDMA can be implemented by UTRA (Universal Terrestrial Radio Access) or CDMA 2000. TDMA can be implemented by radio technologies such as GSM (Global System for Mobile Communications) / GPRS (General Packet Radio Service) / EDGE (Data Rate Enhanced GSM Evolution). OFDMA can be implemented by radio technologies such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE802-20, E-UTRA (Evolved UTRA), etc. UTRA is part of UMTS (Universal Mobile Telecommunications System). 3GPP (3rd Generation Partnership Project) LTE (Long Term Evolution) is part of E-UMTS (Evolved UMTS) using E-UTRA, and LTE-A (Advanced) / LTE-Apro is an advanced version of 3GPP LTE. 3GPP NR (New Radio or New Radio Access Technology) is an advanced version of 3GPP LTE / LTE-A / LTE-Apro.

[0036] In order to make the description clearer, the description is based on the 3GPP communication system (e.g., LTE-A, NR), but the technical idea of ​​the present disclosure is not limited to this. LTE means the technology after 3GPP TS (Technical Specification) 36.xxx version 8. Specifically, the LTE technology in or after 3GPP TS 36.xxx version is called LTE-A, and the LTE technology in or after 3GPP TS 36.xxx version 13 is called LTE-A pro. 3GPP NR means the technology in or after TS 38.xxx version. LTE / NR can be referred to as a 3GPP system. "xxx" means the detailed number of the standard document. LTE / NR can generally be referred to as a 3GPP system. For the background technology, terms, abbreviations, etc. used to describe the present disclosure, reference can be made to the matters described in the standard documents disclosed before the present disclosure. For example, reference can be made to the following documents.

[0037] For 3GPP LTE, reference may 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 (Overall Description), and TS 36.331 (Radio Resource Control).

[0038] For 3GPP NR, you can refer 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 (NR and NG-RAN (Next Generation Radio Access Network) overall description), and TS 38.331 (Radio Resource Control Protocol Specification).

[0039] Abbreviations of terms that may be used in the present disclosure are defined as follows.

[0040] -BM: Beam Management

[0041] -CQI: Channel Quality Indicator

[0042] -CRI: Channel State Information-Reference Signal Resource Indicator

[0043] -CSI: Channel State Information

[0044] -CSI-IM: Channel State Information-Interference Measurement

[0045] -CSI-RS: Channel State Information-Reference Signal

[0046] -DMRS: Demodulation Reference Signal

[0047] -FDM: Frequency Division Multiplexing

[0048] -FFT: Fast Fourier Transform

[0049] -IFDMA: Interleaved Frequency Division Multiple Access

[0050] -IFFT: Inverse Fast Fourier Transform

[0051] -L1-RSRP: Layer 1 reference signal received power

[0052] -L1-RSRQ: Layer 1 reference signal reception quality

[0053] -MAC: Media Access Control

[0054] -NZP: Non-Zero Power

[0055] -OFDM: Orthogonal Frequency Division Multiplexing

[0056] -PDCCH: Physical Downlink Control Channel

[0057] -PDSCH: Physical Downlink Shared Channel

[0058] -PMI: Precoding matrix indicator

[0059] -RE: Resource Element

[0060] -RI: Rank indicator

[0061] -RRC: Radio Resource Control

[0062] -RSSI: Received Signal Strength Indicator

[0063] -Rx: Receive

[0064] -QCL: Quasi-Co-located

[0065] -SINR: Signal to Interference and Noise Ratio

[0066] -SSB (or SS / PBCH block): synchronization signal block (including PSS (primary synchronization signal), SSS (secondary synchronization signal) and PBCH (physical broadcast channel))

[0067] -TDM: Time Division Multiplexing

[0068] -TRP: Transmit and Receive Point

[0069] -TRS: Tracking Reference Signal

[0070] -Tx: Send

[0071] -UE: User Equipment

[0072] -ZP: Zero Power

[0073] Overall system

[0074] As more communication devices require higher capacity, there has been a demand for improved mobile broadband communications compared to existing radio access technologies (RATs). In addition, large-scale MTC (machine type communication) that provides various services anytime and anywhere by connecting multiple devices and things is also one of the main issues to be considered in the next generation of communications. In addition, the design of communication systems considering services / terminals that are sensitive to reliability and latency is also discussed. Therefore, the introduction of next-generation RATs considering eMBB (enhanced mobile broadband communication), mMTC (massive MTC), URLLC (ultra-reliable low-latency communication), etc. is discussed, and for convenience, the corresponding technology is referred to as NR in this disclosure. NR is an expression representing an example of 5G RAT.

[0075] The new RAT system including NR uses an OFDM transmission method or a transmission method similar thereto. The new RAT system may follow OFDM parameters different from those of LTE. Alternatively, the new RAT system follows the parameters of the existing LTE / LTE-A as is, but may support a wider system bandwidth (e.g., 100 MHz). Alternatively, a cell may support multiple parameter sets. In other words, terminals operating according to different parameter sets may coexist in one cell.

[0076] A parameter set corresponds to one subcarrier spacing in the frequency domain. As the reference subcarrier spacing is scaled by an integer N, different parameter sets can be defined.

[0077] Figure 1 The structure of a wireless communication system to which the present disclosure can be applied is illustrated.

[0078] Reference Figure 1 , NG-RAN is configured with gNBs that provide the control plane (RRC) protocol side for the NG-RA (NG Radio Access) user plane (i.e., the new AS (Access Stratum) sublayer / PDCP (Packet Data Convergence Protocol) / RLC (Radio Link Control) / MAC / PHY) and the UE. The gNBs are interconnected through the Xn interface. In addition, the gNBs are connected to the NGC (Next Generation Core) through the NG interface. More specifically, the gNB is connected to the AMF (Access and Mobility Management Power) through the N2 interface, and to the UPF (User Plane Function) through the N3 interface.

[0079] Figure 2 The frame structure in a wireless communication system to which the present disclosure can be applied is illustrated.

[0080] The NR system may support multiple parameter sets. Here, the parameter set may be defined by subcarrier spacing and cyclic prefix (CP) overhead. Here, multiple subcarrier spacings may be derived by scaling the basic (reference) subcarrier spacing by an integer N (or, μ). In addition, although it is assumed that very low subcarrier spacing is not used in very high carrier frequencies, the parameter set used may be selected independently of the frequency band. In addition, various frame structures according to multiple parameter sets may be supported in the NR system.

[0081] In the following, OFDM parameter sets and frame structures that can be considered in the NR system are described. Multiple OFDM parameter sets supported in the NR system can be defined as shown in Table 1 below.

[0082] [Table 1]

[0083] μ <![CDATA[Δf=2 μ ·15[kHz]]]> CP 0 15 normal 1 30 normal 2 60 Normal, Extended 3 120 normal 4 240 normal

[0084] NR supports multiple parameter sets (or subcarrier spacing (SCS)) for supporting various 5G services. For example, when the SCS is 15kHz, the wide area of ​​the traditional cellular band is supported; and when the SCS is 30kHz / 60kHz, dense cities, lower latency and wider carrier bandwidth are supported; and when the SCS is 60kHz or higher, bandwidths exceeding 24.25GHz are supported to overcome phase noise. The NR band is defined as two types of frequency ranges (FR1, FR2). FR1 and FR2 can be configured as shown in Table 2 below. In addition, FR2 can mean millimeter wave (mmW).

[0085] [Table 2]

[0086] Frequency range specification Corresponding frequency range Subcarrier spacing FR1 410MHz–7125MHz 15,30,60kHz FR2 24250MHz–52600MHz 60,120,240kHz

[0087] Regarding the frame structure in the NR system, the sizes of various fields in the time domain are expressed as T c =1 / (Δf max ·N f ) is a multiple of the time unit. Here, Δf max 480·10 3 Hz, and N f is 4096. Downlink and uplink transmissions are configured (organized) to have duration T f =1 / Δf max N f / 100)T c =10ms radio frame. Here, the radio frame is configured with 10 subframes, each of which has T sf =(Δf max N f / 1000)·T c =1 ms duration. In this case, there may be one frame set for the uplink and one frame set for the downlink. Furthermore, the transmission in the i-th uplink frame from the terminal should start T earlier than the corresponding downlink frame in the corresponding terminal. TA =(N TA +N TA,offset )T c For subcarrier spacing configuration μ, the time slots are arranged in n subframes. s μ ∈{0,...,N slot subframe,μ -1} and in the radio frame the number is incremented by n s,f μ ∈{0,...,N slot frame,μ -1}. A time slot is configured with N symb slotconsecutive OFDM symbols, and N symb slot Determined according to CP. Time slot n in a subframe s μ The beginning of the OFDM symbol n in the same subframe s μ N symb slot All terminals may not perform transmission and reception at the same time, which means that all OFDM symbols of a downlink time slot or an uplink time slot may not be used. Table 3 shows the number of OFDM symbols per time slot in a normal CP (N symb slot ), the number of time slots per radio frame (N slot frame,μ ) and the number of time slots per subframe (N slot subframe,μ ), and Table 4 represents 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.

[0088] [Table 3]

[0089] μ <![CDATA[N symb slot ]]> <![CDATA[N slot frame,μ ]]> <![CDATA[N slot subframe,μ ]]> 0 14 10 1 1 14 20 2 2 14 40 4 3 14 80 8 4 14 160 16

[0090] [Table 4]

[0091] μ <![CDATA[N symb slot ]]> <![CDATA[N slot frame,μ ]]> <![CDATA[N slot subframe,μ ]]> 2 12 40 4

[0092] Figure 2 is an example of μ=2 (SCS is 60kHz), see Table 3, 1 subframe can include 4 time slots. Figure 2 1 subframe = {1,2,4} shown in is an example, and the number of time slots that can be included in 1 subframe is defined as in Table 3 or Table 4. In addition, a mini time slot may include 2, 4 or 7 symbols or more or less symbols. Regarding the physical resources in the NR system, antenna ports, resource grids, resource elements, resource blocks, carrier parts, etc. can be considered. In the following, the physical resources that can be considered in the NR system will be described in detail. First, with respect to antenna ports, antenna ports are defined so that the channel carrying the symbols in the antenna port can be inferred from the channel carrying other symbols in the same antenna port. When the large-scale properties of the channel on which the symbols in one antenna port are carried can be inferred from the channel carrying the symbols of another antenna port, it can be said that the two antenna ports are in a QC / QCL (quasi-co-located or quasi-co-located) relationship. In this case, the large-scale properties include at least one of delay spread, Doppler spread, frequency shift, average received power, and receive timing. Figure 3 A resource grid in a wireless communication system to which the present disclosure can be applied is illustrated.

[0093] Reference Figure 3 , which graphically depicts a resource grid configuration with N in the frequency domain RB μ N sc RB subcarriers, and one subframe is configured with 14·2 μ OFDM symbols, but not limited to this. In the NR system, the transmitted signal consists of 2 μ N symb (μ) OFDM symbols and N RB μ N sc RB Here, N RB μ ≤N RB max,μ . N RB max,μ represents the maximum transmission bandwidth, which may differ between uplink and downlink and between parameter sets. In this case, one resource grid can be configured for each μ and antenna port p. Each element of the resource grid for μ and antenna port p is called a resource element and is uniquely identified by an index pair (k, l'). Here, k = 0, ..., N RB μ N sc RB -1 is the index in the frequency domain, and l'=0,...,2 μ N symb (μ) -1 refers to the symbol position in the subframe. When referencing a resource element in a slot, an index pair (k, l) is used. Here, l = 0, ..., N symb μ -1. The resource element (k, l') for μ and antenna port p corresponds to the complex value a k,l' (p,μ) When there is no risk of aliasing or when no specific antenna port or parameter set is specified, the indices p and μ may be dropped and the complex value may be ak,l'(p) or ak,l'. In addition, a resource block (RB) is defined as N in the frequency domain. sc RB =12 consecutive subcarriers.

[0094] Point A serves as a common reference point for the resource block grid and is obtained as follows.

[0095] -OffsetToPointA for the primary cell (PCell) downlink represents the frequency offset between point A and the lowest subcarrier of the lowest resource block overlapping with the SS / PBCH block, which is used by the terminal for initial cell selection. Assuming that a subcarrier spacing of 15kHz is used for FR1 and a subcarrier spacing of 60kHz is used for FR2, it is expressed in resource blocks.

[0096] -absoluteFrequencyPointA represents the frequency position of point A, expressed in ARFCN (Absolute Radio Frequency Channel Number).

[0097] For subcarrier spacing configuration μ, the common resource blocks are numbered from 0 upwards in the frequency domain. The center of subcarrier 0 of common resource block 0 for subcarrier spacing configuration μ is the same as "point A". Common resource block number n for subcarrier spacing configuration μ in the frequency domain CRB μ The relationship between and resource element (k, l) is given as follows in Equation 1.

[0098] [Formula 1]

[0099]

[0100] In Equation 1, k is defined relative to point A, so that k=0 corresponds to a subcarrier centered at point A. Physical resource blocks are spaced from 0 to N in a bandwidth part (BWP). BWP,i size,μ -1 numbering and i is the number of BWP. Physical resource block n in BWPi PRB and public resource block n CRB The relationship between is given by the following formula 2.

[0101] [Formula 2]

[0102]

[0103] N BWP,i start,μ is the common resource block where the BWP starts relative to common resource block 0.

[0104] Figure 4 The physical resource blocks in the wireless communication system to which the present disclosure can be applied are illustrated. Figure 5 The time slot structure in a wireless communication system to which the present disclosure can be applied is illustrated.

[0105] Reference Figure 4 and Figure 5 , a time slot includes multiple symbols in the time domain. For example, for a normal CP, 1 time slot includes 7 symbols, but for an extended CP, 1 time slot includes 6 symbols

[0106] A carrier includes multiple subcarriers in the frequency domain. An RB (resource block) is defined as multiple (e.g., 12) consecutive subcarriers in the frequency domain. A BWP (bandwidth part) is defined as multiple consecutive (physical) resource blocks in the frequency domain and may correspond to a parameter set (e.g., SCS, CP length, etc.). A carrier may include up to N (e.g., 5) BWPs. Data communication may be performed through an activated BWP, and only one BWP may be activated for a terminal. In a resource grid, each element is called a resource element (RE) and may map a complex symbol.

[0107] In the NR system, each component carrier (CC) can support up to 400MHz. If a terminal operating in such a wideband CC always operates to turn on the radio frequency (FR) chip for the entire CC, the terminal battery consumption may increase. Alternatively, when considering multiple application scenarios operating in a wideband CC (e.g., eMBB, URLLC, Mmtc, V2X, etc.), different parameter sets (e.g., subcarrier spacing, etc.) can be supported in each frequency band in the corresponding CC. Alternatively, each terminal may have different capabilities for the maximum bandwidth. Taking this into account, the base station can instruct the terminal to operate only in part of the bandwidth instead of the full bandwidth of the wideband CC, and for convenience, the corresponding partial bandwidth is defined as a bandwidth part (BWP). The BWP can be configured with continuous RBs on the frequency axis and can correspond to a parameter set (e.g., subcarrier spacing, CP length, slot / mini slot duration).

[0108] In addition, even in one CC configured to the terminal, the base station can configure multiple BWPs. For example, a BWP occupying a relatively small frequency domain can be configured in the PDCCH monitoring time slot, and the PDSCH indicated by the PDCCH can be scheduled in a larger BWP. Alternatively, when the UE is congested in a specific BWP, other BWPs can be configured for some terminals for load balancing. Alternatively, considering the frequency domain inter-cell interference elimination between adjacent cells, some full-bandwidth intermediate spectrums can be excluded, and BWPs on two edges can be configured in the same time slot. In other words, the base station can configure at least one DL / UL BWP to a terminal associated with a broadband CC. The base station can activate at least one DL / UL BWP in the configured DL / UL BWP at a specific time (via L1 signaling or MAC CE (control element) or RRC signaling, etc.). In addition, the base station can indicate switching to other configured DL / UL BWPs (via L1 signaling or MAC CE or RRC signaling, etc.). Alternatively, based on a timer, when the timer value expires, it can switch to a determined DL / UL BWP. Here, the activated DL / UL BWP is defined as the active DL / UL BWP. However, when the terminal performs the initial access procedure or establishes the RRC connection before, the configuration on the DL / UL BWP may not be received, so the DL / UL BWP assumed by the terminal in these cases is defined as the initial active DL / UL BWP.

[0109] Figure 6 Physical channels used in a wireless communication system to which the present disclosure can be applied and a general signal transmission and reception method using the physical channels are illustrated.

[0110] 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. The information sent and received by the base station and the terminal includes data and various control information, and there are various physical channels according to the type / purpose of the information they send and receive.

[0111] When the terminal is turned on or newly enters a cell, it performs an initial cell search including synchronization with a base station (S601). For the initial cell search, the terminal can synchronize with the base station by receiving a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) from the base station, and obtain information such as a cell identifier (ID). Then, the terminal can obtain broadcast information in the cell by receiving a physical broadcast channel (PBCH) from the base station. In addition, the terminal can check the downlink channel status by receiving a downlink reference signal (DLRS) in the initial cell search phase.

[0112] The terminal that has completed the initial cell search may obtain more detailed system information by receiving a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH) according to information carried in the PDCCH (S602).

[0113] In addition, when the terminal accesses the base station for the first time or there are no radio resources for signal transmission, it can perform a random access (RACH) process (S603 to S606) on the base station. For the random access process, the terminal can send a specific sequence as a preamble through a physical random access channel (PRACH) (S603 and S605), and can receive a response message to the preamble through a PDCCH and a corresponding PDSCH (S604 and S606). The contention-based RACH can additionally perform a contention resolution process.

[0114] The terminal that subsequently performs the above process may perform PDCCH / PDSCH reception (S607) and PUSCH (Physical Uplink Shared Channel) / PUCCH (Physical Uplink Control Channel) transmission (S608) as a general uplink / downlink signal transmission process. Specifically, the terminal receives downlink control information (DCI) through PDCCH. Here, DCI includes control information such as resource allocation information for the terminal, and the format varies according to its purpose of use.

[0115] In addition, the control information sent by the terminal to the base station through the uplink or received by the terminal from the base station includes downlink / uplink ACK / NACK (acknowledgement / non-acknowledgement) signal, CQI (channel instruction indicator), PMI (precoding matrix indicator), RI (rank indicator), etc. For the 3GPP LTE system, the terminal can send the above-mentioned CQI / PMI / RI and other control information through PUSCH and / or PUCCH.

[0116] Table 5 shows an example of the DCI format in the NR system.

[0117] [Table 5]

[0118]

[0119] Referring to Table 5, DCI formats 0_0, 0_1, and 0_2 may include resource information (e.g., UL / SUL (supplementary UL), frequency resource allocation, time resource allocation, frequency hopping, etc.), information related to transport blocks (TBs) (e.g., MCS (modulation coding and scheme), NDI (new data indicator), RV (redundancy version), etc.), information related to HARQ (hybrid-automatic repeat and request) (e.g., process number, DAI (downlink assignment index), PDSCH-HARQ feedback timing, etc.), information related to multiple antennas (e.g., DMRS sequence initialization information, antenna port, CSI request, etc.), power control information related to the scheduling of PUSCH (e.g., PUSCH power control, etc.), and control information included in each DCI format may be predefined. DCI format 0_0 is used to schedule PUSCH in one cell. The information included in DCI format 0_0 is a CRC (Cyclic Redundancy Check) scrambled by C-RNTI (Cell Radio Network Temporary Identifier) ​​or CS-RNTI (Configured Scheduling RNTI) or MCS-C-RNTI (Modulation Coding Scheme Cell RNTI) and sent. DCI format 0_1 ​​is used to indicate the scheduling of one or more PUSCHs or to configure grant (CG) downlink feedback information to a terminal in a cell. The information included in DCI format 0_1 ​​is scrambled and sent by C-RNTI or CS-RNTI or SP-CSI-RNTI (Semi-Persistent CSI RNTI) or MCS-C-RNTI. DCI format 0_2 is used to schedule PUSCH in a cell. The information included in DCI format 0_2 is scrambled and sent by C-RNTI or CS-RNTI or SP-CSI-RNTI or MCS-C-RNTI. Next, DCI formats 1_0, 1_1 and 1_2 may include resource information (e.g., frequency resource allocation, time resource allocation, VRB (virtual resource block) -PRB (physical resource block) mapping, etc.), information related to transport blocks (TBs) (e.g., MCS, NDI, RV, etc.), information related to HARQ (e.g., process number, DAI, PDSCH-HARQ feedback timing, etc.), information related to multiple antennas (e.g., antenna ports, TCI (transmission configuration indicator), SRS (sounding reference signal) request, etc.), information related to PUCCH scheduling regarding PDSCH (e.g., PUCCH power control, PUCCH resource indicator, etc.), and the control information included in each DCI format may be predefined.

[0120] DCI format 1_0 is used to schedule PDSCH in one DL cell. Information included in DCI format 1_0 is CRC scrambled and transmitted by C-RNTI or CS-RNTI or MCS-C-RNTI.

[0121] DCI format 1_1 is used to schedule PDSCH in one cell. Information included in DCI format 1_1 is CRC scrambled and transmitted by C-RNTI or CS-RNTI or MCS-C-RNTI.

[0122] DCI format 1_2 is used to schedule PDSCH in one cell. Information included in DCI format 1_2 is CRC scrambled and transmitted by C-RNTI, CS-RNTI, or MCS-C-RNTI.

[0123] Operations related to multiple TRPs

[0124] The coordinated multi-point (CoMP) scheme refers to a scheme in which multiple base stations effectively control interference by exchanging (for example, using an X2 interface) or utilizing channel information (for example, RI / CQI / PMI / LI (layer indicator), etc.) fed back by a terminal and cooperatively sent to the terminal. Depending on the scheme used, CoMP can be classified into joint transmission (JT), coordinated scheduling (CS), coordinated beamforming (CB), dynamic point selection (DPS), dynamic point blocking (DPB), etc.

[0125] The M-TRP transmission scheme in which M TRPs send data to one terminal can be largely classified into i) eMBBM-TRP transmission, which is a scheme for improving the transmission rate and ii) URLLC M-TRP transmission, which is a scheme for improving the reception success rate and reducing the delay.

[0126] In addition, regarding DCI transmission, the M-TRP transmission scheme can be classified into i) M-TRP transmission based on M-DCI (multiple DCI) in which each TRP sends different DCI and ii) M-TRP transmission based on S-DCI (single DCI) in which one TRP sends DCI. For example, for M-TRP transmission based on S-DCI, all scheduling information about data sent by M TRPs should be delivered to the terminal through one DCI, which can be used in an ideal backhaul (ideal BH) environment where dynamic collaboration between two TRPs is possible.

[0127] For TDM-based URLLC M-TRP transmission, Scheme 3 / 4 is under discussion for standardization. Specifically, Scheme 4 means a scheme in which one TRP sends a transport block (TB) in one time slot, and it has the effect of improving the probability of receiving data of the same TB received from multiple TRPs in multiple time slots. In addition, Scheme 3 means a scheme in which one TRP sends a TB through a continuous number of OFDM symbols (i.e., symbol groups), and the TRP can be configured to send the same TB through different symbol groups in one time slot.

[0128] In addition, the UE may identify a PUSCH (or PUCCH) scheduled by a DCI received in a different control resource set (CORESET) (or a CORESET belonging to a different CORESET group) as a PUSCH (or PUCCH) sent to a different TRP, or may identify a PDSCH (or PDCCH) from a different TRP. In addition, the method described below for UL transmissions (e.g., PUSCH / PUCCH) sent to different TRPs may be equally applied to UL transmissions (e.g., PUSCH / PUCCH) sent to different panels belonging to the same TRP.

[0129] Hereinafter, non-coherent joint transmission (NCJT) based on multiple DCIs / NCJT based on a single DCI will be described.

[0130] NCJT (Non-coherent Joint Transmission) is a scheme in which multiple transmission points (TPs) send data to one terminal by using the same time-frequency resources, and the TPs send data by using different DMRSs (Demodulation Multiplexing Reference Signals) through different layers (i.e., through different DMRS ports) between TPs.

[0131] TP transmits data scheduling information to the terminal receiving NCJT through DCI. Here, a scheme in which each TP participating in NCJT transmits scheduling information on its own data sent through DCI is called "NCJT based on multiple DCIs". When each of the N TPs participating in NCJT transmission sends DL authorization DCI and PDSCH to the UE, the UE receives N DCIs and N PDSCHs from the N TPs. In addition, a scheme in which a representative TP transmits scheduling information on the data sent by itself and the data sent by different TPs (i.e., TPs participating in NCJT) through one DCI is called "NCJT based on a single DCI". Here, N TPs send one PDSCH, but each TP only sends some layers of the multiple layers included in one PDSCH. For example, when sending 4 layers of data, TP1 can send 2 layers, and TP2 can send the remaining 2 layers to the UE.

[0132] Multiple TRPs (MTRPs) performing NCJT transmission can send DL data to the terminal by using any of the following two schemes.

[0133] First, the "MTRP scheme based on a single DCI" is described. The MTRP transmits one common PDSCH cooperatively, and each TRP participating in the cooperative transmission is spatially divided and sends the corresponding PDSCH to different layers (i.e., different DMRS ports) by using the same time-frequency resources. Here, the scheduling information about the PDSCH is indicated to the UE through one DCI, and which DMRS (group) port uses which QCL RS and QCL type information are indicated by the corresponding DCI (which is different from the DCI indicating the QCL RS and the type that will be applied to all DMRS ports in common as indicated in the existing scheme). In other words, M TCI states (for example, M=2 for 2TRP cooperative transmission) can be indicated by the TCI (transmission configuration indicator) field in the DCI, and the QCL RS and type can be indicated by using M different TCI states for M DMRS port groups. In addition, the DMRS port information can be indicated by using a new DMRS table.

[0134] Next, the "MTRP scheme based on multiple DCIs" is described. Each MTRP sends different DCIs and PDSCHs, and (partially or fully) the corresponding PDSCHs overlap with each other and are sent in frequency-time resources. The corresponding PDSCHs can be scrambled by different scrambling IDs (identifiers), and the DCI can be sent by CORESETs belonging to different CORESET groups. (Here the CORESET group can be identified by an index defined in the CORESET configuration of each CORESET. For example, when index = 0 is configured for CORESET1 and CORESET2 and index = 1 is configured for CORESET3 and CORESET4, CORESET1 and CORESET2 are CORESET group 0, and CORESET3 and CORESET4 belong to CORESET group 1. In addition, when the index is not defined in the CORESET, it can be interpreted as index = 0) When multiple scrambling IDs are configured in one serving cell or two or more CORESET groups are configured, the UE can notice that it receives data according to the MTRP operation based on multiple DCIs.

[0135] Alternatively, the MTRP scheme based on a single DCI or the MTRP scheme based on multiple DCIs may be indicated to the UE by separate signaling. In the example, for one serving cell, multiple CRS (cell reference signal) patterns for MTRP operation may be indicated to the UE. In this case, depending on the MTRP scheme based on a single DCI or the MTRP scheme based on multiple DCIs (because the CRS patterns are different), the PDSCH rate matching for CRS may be different.

[0136] In the following, the CORESET group ID described / mentioned in the present disclosure may represent index / identification information (e.g., ID, etc.) for distinguishing the CORESET of each TRP / panel. In addition, the CORESET group may be a group / collection of CORESETs distinguished by index / identification information (e.g., ID) / CORESET group ID, etc. for distinguishing the CORESET of each TRP / panel. In an example, the CORESET group ID may be specific index information defined in the CORESET configuration. In this case, the CORESET group may be configured / indicated / defined by an index defined in the CORESET configuration of each CORESET. Additionally / alternatively, the CORESET group ID may represent index / identification information / indicator, etc. for distinguishing / identifying between the CORESETs configured / associated with each TRP / panel. In the following, the CORESET group ID described / mentioned in the present disclosure may be represented by replacing it with a specific index / specific identification information / specific indicator for distinguishing / identifying between the CORESETs configured / associated with each TRP / panel. The CORESET group ID (i.e., a specific index / specific identification information / specific indicator for distinguishing / identifying between configured / associated CORESETs for each TRP / panel) may be configured / indicated to the terminal through higher layer signaling (e.g., RRC signaling) / L2 signaling (e.g., MAC-CE) / L1 signaling (e.g., DCI), etc. In an example, it may be configured / indicated so that PDCCH detection is performed for each TRP / panel in a cell of the corresponding CORESET group (i.e., for TRPs / panels belonging to the same CORESET group). Additionally / alternatively, it may be configured / indicated so 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 separated and managed / controlled for each TRP / panel in a cell of the corresponding CORESET group (i.e., for TRPs / panels belonging to the same CORESET group). Additionally / alternatively, HARQ A / N (processing / retransmission) etc. for PDSCH / PUSCH etc. scheduled for each TRP / panel may be managed for the corresponding CORESET group (ie, for TRPs / panels belonging to the same CORESET group).

[0137] Hereinafter, a partially overlapping NCJT will be described.

[0138] In addition, NCJT can be classified into fully overlapping NCJT in which the time-frequency resources transmitted by each TP are completely overlapped and partially overlapping NCJT in which only some time-frequency resources are overlapped. In other words, for partially overlapping NCJT, data of both TP1 and TP2 are transmitted in some time-frequency resources, and data of only one TP in TP1 or TP2 is transmitted in the remaining time-frequency resources.

[0139] Hereinafter, a method for improving reliability in multi-TRP will be described.

[0140] As a sending and receiving method for improving reliability using transmission in multiple TRPs, the following two methods can be considered.

[0141] Figure 7 A method for transmitting multiple TRPs in a wireless communication system to which the present disclosure can be applied is illustrated.

[0142] Reference Figure 7 (a) shows a case where layer groups transmitting the same codeword (CW) / transport block (TB) correspond to different TRPs. Here, the layer group may mean a predetermined set of layers including one or more layers. In this case, the advantage is that the amount of transmission resources increases due to the number of multiple layers, so robust channel coding with a low coding rate can be used for the TB, and in addition, since multiple TRPs have different channels, it can be expected to improve the reliability of the received signal based on diversity gain.

[0143] Reference Figure 7 (b) shows an example of sending different CWs through layer groups corresponding to different TRPs. Here, it can be assumed that the TBs corresponding to CW#1 and CW#2 in the figure are identical to each other. In other words, CW#1 and CW#2 mean that the same TB is transformed into different CWs by different TRPs through channel coding, etc. Therefore, an example of repeatedly sending the same TB can be considered. Figure 7 In the case of (b), Figure 7 Compared with (a), it may have the disadvantage of a higher code rate corresponding to the TB. However, it has the advantage that the code rate can be adjusted by indicating different RV (redundancy version) values ​​or the modulation order of each CW can be adjusted for the coded bits generated from the same TB according to the channel environment.

[0144] According to the above Figure 7 (a) and Figure 7The method shown in (b) can improve the data reception probability of the terminal because the same TB is repeatedly sent through different layer groups and each layer group is sent by a different TRP / panel. It is called the M-TRP URLLC transmission method based on SDM (spatial division multiplexing). Layers belonging to different layer groups are sent through DMRS ports belonging to different DMRS CDM groups respectively.

[0145] In addition, the above content related to multiple TRPs is described based on the SDM (spatial division multiplexing) method using different layers, but it can be naturally extended and applied to the FDM (frequency division multiplexing) method based on different frequency domain resources (e.g., RB / PRB (sets), etc.) and / or the TDM (time division multiplexing) method based on different time domain resources (e.g., time slots, symbols, sub-symbols, etc.).

[0146] Regarding methods for URLLC based on multiple TRPs scheduled by a single DCI, the following methods are discussed.

[0147] 1) Method 1 (SDM): Time and frequency resource allocation overlap and n (n<=Ns) TCI states in a single time slot

[0148] 1-a) Method 1a

[0149] - The same TB is transmitted in one layer or one layer set at each transmission time (opportunity), and each layer or each layer set is associated with one TCI and one DMRS port set.

[0150] - Use a single codeword with one RV in all spatial layers or all layer sets. With respect to the UE, different coded bits are mapped to different layers or layer sets by using the same mapping rule.

[0151] 1-b) Method 1b

[0152] - The same TB is transmitted in one layer or one layer set at each transmission time (opportunity), and each layer or each layer set is associated with one TCI and one DMRS port set.

[0153] - Use a single codeword with one RV in each spatial layer or each layer set. The RV corresponding to each spatial layer or each layer set can be the same or different.

[0154] 1-c) Method 1c

[0155] - At one transmission time (opportunity), the same TB having one DMRS port associated with multiple TCI state indexes is transmitted in one layer, or the same TB having multiple DMRS ports associated one-to-one with multiple TCI state indexes is transmitted in one layer.

[0156] In the case of methods 1a and 1c, the same MCS is applied to all layers or all layer sets.

[0157] 2) Method 2 (FDM): Frequency resource allocation does not overlap and n (n<=Nf) TCI states in a single time slot

[0158] - Each non-overlapping frequency resource allocation is associated with one TCI state.

[0159] - The same single / multiple DMRS ports are associated with all non-overlapping frequency resource allocations.

[0160] 2-a) Method 2a

[0161] - A single codeword with one RV is used for all resource allocations. With respect to the UE, a common RB matching (codeword to layer mapping) is applied for all resource allocations.

[0162] 2-b) Method 2b

[0163] - A single codeword with one RV is used for each non-overlapping frequency resource allocation. The RV corresponding to each non-overlapping frequency resource allocation may be the same or different.

[0164] For method 2a, the same MCS is applied to all non-overlapping frequency resource allocations.

[0165] 3) Method 3 (TDM): Time resource allocation does not overlap and n (n<=Nt1) TCI states in a single time slot

[0166] - Each transmission time (opportunity) of a TB has a time granularity of a mini-slot and has one TCI and one RV.

[0167] - A common MCS for all transmission times (opportunities) in a time slot is used with single or multiple DMRS ports.

[0168] -RV / TCI can be the same or different at different transmission times (opportunities).

[0169] 4) Method 4 (TDM): n (n <= Nt2) TCI states in K (n <= K) different time slots

[0170] -Each transmission time (opportunity) of a TB has a TCI and a RV.

[0171] - Every transmission time (opportunity) across K time slots uses a common MCS and single or multiple DMRS ports.

[0172] -RV / TCI can be the same or different at different transmission times (opportunities).

[0173] In the following, MTRP URLLC is described.

[0174] In the present disclosure, DL MTRP URLLC means that multiple TRPs send the same data (e.g., the same TB) / DCI by using different layer / time / frequency resources. For example, TRP 1 sends the same data / DCI in resource 1, and TRP 2 sends the same data / DCI in resource 2. A UE configured with the DL MTRP-URLLC transmission method receives the same data / DCI by using different layer / time / frequency resources. Here, the UE configures from the base station which QCL RS / type (i.e., DL TCI state) should be used in the layer / time / frequency resources for receiving the same data / DCI. For example, when the same data / DCI is received in resource 1 and resource 2, the DL TCI state used in resource 1 and the DL TCI state used in resource 2 can be configured. The UE can achieve high reliability because it receives the same data / DCI through resource 1 and resource 2. This DL MTRP URLLC can be applied to PDSCH / PDCCH.

[0175] In addition, in the present disclosure, UL MTRP-URLLC means that multiple TRPs receive the same data / UCI (uplink control information) from any UE by using different layer / time / frequency resources. For example, TRP 1 receives the same data / DCI from the UE in resource 1, and TRP 2 receives the same data / DCI from the UE in resource 2 to share the received data / DCI through the backhaul link connected between the TRPs. UEs configured with the UL MTRP-URLLC transmission method send the same data / UCI by using different layer / time / frequency resources. In this case, the UE configures from the base station which Tx beam and which Tx power (i.e., UL TCI state) should be used in the layer / time / frequency resource that sends the same data / DCI. For example, when the same data / UCI is sent in resource 1 and resource 2, the UL TCI state used in resource 1 and the UL TCI state used in resource 2 can be configured. Such UL MTRP URLLC can be applied to PUSCH / PUCCH.

[0176] In addition, in the present disclosure, when a specific TCI state (or TCI) is used (or mapped) when receiving data / DCI / UCI for any frequency / time / space resource (layer), it means the following. For DL, it may mean estimating the channel from DMRS by using the QCL type and QCL RS indicated by the corresponding TCI state in the frequency / time / space resource (layer), and the data / DCI is received / demodulated based on the estimated channel. In addition, for UL, it may mean transmitting / modulating DMRS and data / UCI by using the Tx beam and power indicated by the corresponding TCI state in the frequency / time / space resource.

[0177] Here, the UL TCI state has the Tx beam and / or Tx power information of the UE, and the spatial relationship information, etc. can be configured to the UE through other parameters instead of the TCI state. The UL TCI state can be directly indicated by the UL authorization DCI, or it can represent the spatial relationship information of the SRS resource indicated by the SRI (sounding resource indicator) field of the UL authorization DCI. Alternatively, it can mean an open-loop (OL) Tx power control parameter connected to the value indicated by the SRI field of the UL authorization DCI (for example, j: index and α of the open-loop parameter Po (up to 32 parameter value sets per cell), q_d: index of the DLRS resource used for PL (path loss) measurement (up to 4 measurements per cell), l: closed-loop power control process index (up to 2 processes per cell).

[0178] Hereinafter, MTRP eMBB is described.

[0179] In the present disclosure, MTRP-eMBB means that multiple TRPs send different data (e.g., different TBs) by using different layers / times / frequencies. A UE configured with the MTRP-eMBB transmission method receives an indication of multiple TCI states through DCI, and assumes that the data received by using the QCL RS of each TCI state is different data.

[0180] On the other hand, the UE can understand whether it is MTRP URLLC transmission / reception or MTRP eMBB transmission / reception by dividing the RNTI for MTRP-URLLC and the RNTI for MTRP-eMBB respectively and using them. In other words, when the CRC mask of the DCI is performed by using the RNTI for URLLC, the UE considers it as URLLC transmission, and when the CRC mask of the DCI is performed by using the RNTI for eMBB, the UE considers it as eMBB transmission. Alternatively, the base station can configure MTRP URLLC transmission / reception or TRP eMBB transmission / reception to the UE through other new signaling.

[0181] In the description of the present disclosure, for the convenience of description, it is described by assuming collaborative transmission / reception between two TRPs, but the method proposed in the present disclosure can also be extended and applied in 3 or more multi-TRP environments, and in addition, it can also be extended and applied in multiple panel environments (i.e., by matching TRP with the panel). In addition, different TRPs can be identified as different TCI states for the UE. Therefore, when the UE receives / sends data / DCI / UCI by using TCI state 1, it means receiving data / DCI / UCI from TRP 1 / sending data / DCI / UCI to TRP 1.

[0182] Hereinafter, the method proposed in the present disclosure may be utilized when MTRP cooperatively transmits PDCCH (repeatedly transmits or partially transmits the same PDCCH). In addition, the method proposed in the present disclosure may also be utilized when MTRP cooperatively transmits PDSCH or cooperatively receives PUSCH / PUCCH.

[0183] In addition, in the present disclosure, when multiple base stations (i.e., MTRP) repeatedly send the same PDCCH, it may mean that the same DCI is sent through multiple PDCCH candidates, and it may also mean that multiple base stations repeatedly send the same DCI. Here, the same DCI may mean two DCIs with the same DCI format / size / payload. Alternatively, although the two DCIs have different payloads, they can be considered to be the same DCI when the scheduling results are the same. For example, the TDRA (time domain resource allocation) field of the DCI relatively determines the time slot / symbol position of the data and the time slot / symbol position of the A / N (ACK / NACK) based on the reception timing of the DCI, so that if the DCI received at the nth time and the DCI received at the n+1th time inform the UE of the same scheduling result, the TDRA fields of the two DCIs are different, and necessarily, the DCI payloads are different. R (number of repetitions) can be directly indicated by the base station or mutually promised to the UE. Alternatively, although the payloads of the two DCIs are different and the scheduling results are different, when the scheduling result of one DCI is a subset of the scheduling result of the other DCI, they can be considered to be the same DCI. For example, when the same data is repeatedly sent N times through TDM, DCI 1 received before the first data indicates N data repetitions, and DCI 2 received after the first data and before the second data indicates N-1 data repetitions. The scheduled data of DCI 2 becomes a subset of the scheduled data of DCI 1, and the two DCIs schedule the same data, so in this case, they can be considered to be the same DCI.

[0184] In addition, in the present disclosure, when a plurality of base stations (ie, MTRPs) partially transmit the same PDCCH, it means that one DCI is transmitted through one PDCCH candidate, but TRP 1 transmits some resources so that such a PDCCH candidate is defined, and TRP 2 transmits the remaining resources. For example, when a PDCCH candidate corresponding to aggregation level m1+m2 is transmitted by TRP 1 and TRP 2 dividedly, the PDCCH candidate may be divided into PDCCH candidate 1 corresponding to aggregation level m1 and PDCCH candidate 2 corresponding to aggregation level m2, and TRP 1 may transmit PDCCH candidate 1, and TRP 2 may transmit PDCCH candidate 2 to different time / frequency resources. After receiving PDCCH candidate 1 and PDCCH candidate 2, the UE may generate a PDCCH candidate corresponding to aggregation level m1+m2 and attempt DCI decoding.

[0185] In addition, in the present disclosure, when the UE repeatedly sends the same PUSCH so that multiple base stations (i.e., MTRPs) can receive the same PUSCH, it may mean that the UE sends the same data through multiple PUSCHs. In this case, each PUSCH may be optimized and sent to the UL channels of different TRPs. For example, when the UE repeatedly sends the same data through PUSCH 1 and PUSCH 2, PUSCH 1 is sent by using UL TCI state 1 for TRP 1, and in this case, link adaptation such as precoder / MCS, etc. may also be scheduled / applied to the channel optimized value for TRP 1. PUSCH 2 is sent by using UL TCI state 2 for TRP 2, and link adaptation such as precoder / MCS, etc. may also be scheduled / applied to the channel optimized value for TRP 2. In this case, the repeatedly transmitted PUSCH 1 and PUSCH 2 may be sent at different times for TDM, FDM, or SDM.

[0186] In addition, in the present disclosure, when the UE partially transmits the same PUSCH so that multiple base stations (i.e., MTRPs) can receive the PUSCH, it may mean that the UE transmits one data through one PUSCH, but it divides the resources allocated to the PUSCH, optimizes them for UL channels of different TRPs, and transmits them. For example, when the UE transmits the same data through a 10-symbol PUSCH, the data is transmitted by using UL TCI state 1 for TRP 1 in 5 previous symbols, and in this case, link adaptation such as precoder / MCS, etc. may also be scheduled / applied to the channel optimized value for TRP 1. The remaining data is transmitted in the remaining 5 symbols by using UL TCI state 2 for TRP 2, and in this case, link adaptation such as precoder / MCS, etc. may also be scheduled / applied to the channel optimized value for TRP 2. In the example, transmission for TRP 1 and transmission for TRP 2 are TDMed by dividing one PUSCH into time resources, but may be transmitted by the FDM / SDM method.

[0187] In addition, similar to the above-mentioned PUSCH transmission, also for PUCCH, the UE can repeatedly send the same PUCCH or can partially send the same PUCCH so that multiple base stations (ie, MTRP) receive it.

[0188] Hereinafter, the proposal of the present disclosure may be extended and applied to various channels such as PUSCH / PUCCH / PDSCH / PDCCH, etc.

[0189] The proposal of the present disclosure may be extended and applied to the case where various uplink / downlink channels are repeatedly transmitted to different time / frequency / space resources and the case where various uplink / downlink channels are partially transmitted to different time / frequency / space resources.

[0190] In the present disclosure, a transmission opportunity (TO) may correspond to a resource unit for transmitting / receiving a channel or a candidate resource unit for transmitting / receiving a channel. For example, when multiple channels are transmitted according to a TDM scheme, a TO may mean each channel transmitted or can be transmitted in different time resources. For example, when multiple channels are transmitted according to an FDM scheme, a TO may mean each channel transmitted or can be transmitted in different frequency resources (e.g., RBs). For example, when multiple channels are transmitted according to an SDM scheme, a TO may mean each channel transmitted or can be transmitted in different layers / beams / DMRS ports. A TCI state may be mapped to each TO. When the same channel is transmitted repeatedly, a complete DCI / data / UCI may be transmitted in one TO, and the receiving end may receive multiple TOs to increase the reception success rate.

[0191] The above-mentioned multi-TB PUSCH / PDSCH scheduling scheme based on a single DCI (S-DCI) can be applied to the case where, for example, one DCI simultaneously schedules multiple PUSCH / PDSCHs in a very high frequency band (e.g., a frequency band higher than 5.26 GHz). For example, multiple time domain resource allocations (TDRA) (or TO) can be indicated at once by the TDRA field of the DCI for scheduling PUSCH, and different TBs can be sent by PUSCH in each TO. The frequency domain resource allocation (FDRA), MCS, transmit precoding matrix indicator (TPMI), and SRI values ​​of the multi-TB PUSCH of the scheduling DCI can be commonly applied to multiple TBs scheduled by the corresponding DCI. In addition, NDI and RV can be indicated separately / independently for each TB by the multi-TB PUSCH of the scheduling DCI. In addition, in this multi-TB PUSCH of the scheduling DCI, a value is indicated for the HARQ (process) number (HPN), but a value that increases sequentially from the initial TO in the TO order can be applied.

[0192] In addition, an S-DCI-based M-TRP PUSCH repetition transmission scheme can be considered. In this regard, the base station configures two SRS sets to the terminal for S-DCI-based M-TRP PUSCH transmission, and each set is used to indicate the UL Tx port and UL beam / QCL information for / to TRP 1 and TRP 2. In addition, the base station performs SRS resource indication for each SRS resource set, and can indicate up to two PC parameter sets by including two SRI fields in one DCI.

[0193] For example, the first SRI field may indicate the SRS resources and PC parameter set defined in SRS resource set 0, and the second SRI field may indicate the SRS resources and PC parameter set defined in SRS resource set 1. The terminal may receive an indication of the UL Tx port, PC parameter set, and UL beam / QCL information for TRP 1 through the first SRI field, by which the terminal performs PUSCH transmission in the TO corresponding to the SRS resource set 0. Similarly, the terminal may receive an indication of the UL Tx port, PC parameter set, and UL beam / QCL information for TRP 2 through the second SRI field, by which the terminal may perform PUSCH transmission in the TO corresponding to the SRS resource set 1.

[0194] In addition to the above-mentioned SRI field, the existing one field may be extended to two fields so that TPMI, PTRS, and TPC-related fields may be indicated for each TRP.

[0195] In addition, an SRS resource set indication field (e.g., a 2-bit field) can be defined, and based on this, the terminal can perform S-TRP PUSCH repetition transmission by selecting a specific one of the two SRS resource sets, or can perform M-TRP PUSCH repetition transmission by selecting both SRS resource sets.

[0196] For example, the code point "00" of the SRS resource set indication field may indicate a first SRS resource set, and the code point "01" may indicate a second SRS resource set / definition. When the code point "00" or "01" is indicated, S-TRP PUSCH transmission corresponding to the SRS resource set indicated by each code point may be performed. In addition, the code point "10" may be configured / defined to indicate [first SRS resource set, second SRS resource set], and the code point "11" may be configured / defined to indicate [second SRS resource set, first SRS resource set]. When the code point "10" or "11" is indicated, M-TRP PUSCH transmission may be performed in the order in which the SRS resource set pairs are indicated. When the code point "10" is indicated, the first SRS resource set corresponds to the first PUSCH TO, and when the code point "11" is indicated, the second SRS resource set corresponds to the first PUSCH TO.

[0197] In addition, an M-TRP repeated PUCCH transmission scheme based on a single PUCCH resource can be considered. In this regard, for M-TRP PUCCH transmission based on a single PUCCH resource, the base station can activate / configure two spatial relationship information to the terminal on a single PUCCH resource (if FR1, two PC parameter sets can be activated / configured). When ULUCI is sent through the corresponding PUCCH resource, each spatial relationship information is used to indicate the spatial relationship information about TRP 1 and TRP 2 to the terminal respectively. For example, the Tx beam / PC parameters about TRP 1 are indicated to the terminal through the value indicated in the first spatial relationship information, and the terminal performs PUCCH transmission in the TO corresponding to TRP 1 by using the corresponding information. Similarly, the Tx beam / PC parameters about TRP 2 are indicated to the terminal through the value indicated in the second spatial relationship information, and the terminal performs PUCCH transmission in the TO corresponding to TRP 2 by using the corresponding information.

[0198] In addition, for the repeated transmission of M-TRP PUCCH, the configuration method has been improved so that two spatial relationship information can be configured in the PUCCH resources. That is, when the power control (PC) parameters such as PLRS, Alpha, P0 and closed-loop index are set / configured for each spatial relationship information, the spatial relationship RS can be configured. Therefore, the PC information and spatial relationship RS information corresponding to the two TRPs can be configured by two spatial relationship information. In this way, the terminal sends UCI (i.e., CSI, ACK / NACK, SR, etc.) PUCCH in the first TO by using the first spatial relationship information, and sends the same UCIPUCCH in the second TO by using the second spatial relationship information. In the present disclosure, the PUCCH resources configured with two spatial relationship information may be referred to as M-TRP PUCCH resources, and the PUCCH resources configured with one spatial relationship information may be referred to as S-TRPPUCCH resources.

[0199] In addition, regarding the proposal of the present disclosure, a unified TCI framework solution may be considered. That is, the UL TCI state and the DL TCI state may be indicated together through DL DCI (e.g., DCI format 1_1 / 1_2, etc.). Alternatively, only the UL TCI state may be indicated without indicating the DL TCI state through DL DCI. In this way, the conventional solution for UL beam and power control (PC) configuration may be replaced by the above-mentioned UL TCI state indication solution.

[0200] As a specific example, one UL TCI state may be indicated by the TCI field in the DL DCI. In this case, the UL TCI state may be applied to all PUSCH / PUCCHs after a specific time (e.g., beam application time) and may be applied to some or all of the indicated SRS resource sets. Alternatively, multiple UL TCI states (and / or DL ​​TCI states) may be indicated by the TCI field in the DL DCI.

[0201] A new method is being discussed in which a terminal simultaneously transmits multiple channels (CH) / reference signals (RS) of the same type, and a terminal simultaneously transmits multiple CH / RS of different types. In a conventional scheme, the operation of a terminal transmitting multiple CH / RS at one point in time (or within a time unit) is restricted. For example, for a terminal according to a conventional scheme, simultaneous transmission of multiple SRS resources belonging to different SRS resource sets is supported for uplink beam measurement, but simultaneous transmission of multiple different PUSCHs is not supported. Therefore, in order to support more advanced terminal operations by alleviating the above limitations, a method of simultaneously transmitting multiple CH / RS using multiple transmission elements of a terminal is being discussed.

[0202] For example, according to the present disclosure, a terminal can use multiple transmission elements to perform uplink transmission for multiple transmission targets at the same time. In addition, the base station can simultaneously receive uplink transmissions sent by multiple transmission elements from terminals in multiple transmission targets. For example, the transmission element of the terminal can correspond to an antenna group or an antenna panel, and one antenna group / panel can correspond to an RS set (or an RS candidate set). That is, the antenna group / panel can be indicated / identified by an RS (candidate) set, for example, the transmission target of the uplink transmission from the terminal can correspond to a TRP or a cell, and one TRP / cell can correspond to a CORESET group / pool. That is, the TRP / cell can be indicated / identified by a CORESET group / pool. For example, a simultaneous uplink transmission scheme for multiple transmission targets through multiple transmission elements can be referred to as simultaneous transmission across multiple panels (STxMP). However, the scope of the present disclosure is not limited by the name of the transmission scheme, the example of the unit of the transmission element, and / or the example of the unit of the transmission target.

[0203] As an example of STxMP operation, two PUSCHs corresponding to two UL TBs may be scheduled on the same RB (e.g., a first PUSCH carrying a first TB, a second PUSCH carrying a second TB). In addition, a separate TCI state may be configured / indicated for each of a plurality of PUSCH transmissions. A plurality of TCI states may correspond to a plurality of transmission elements (e.g., a panel / RS set), respectively. In addition, a transmission element may correspond to a transmission target, respectively, and a plurality of transmission elements may correspond to a transmission target.

[0204] For example, a first spatial relationship RS and a first power control (PC) parameter set (or a first UL TCI state) may be configured / indicated for a first PUSCH transmission, and a second spatial relationship RS and a second PC parameter set (or a second UL TCI state) may be configured / indicated for a second PUSCH transmission. For example, a terminal may transmit a first PUSCH using a first panel corresponding to a first UL TCI state in a first time unit, and may transmit a second PUSCH using a second panel corresponding to a second UL TCI state in a first time unit. For example, a terminal may transmit a first PUSCH through a first RS set (for a first CORESET pool) based on a first UL TCI state in a first time unit, and may transmit a second PUSCH through a second RS set (for a second CORESET pool) based on a second UL TCI in a first time unit. A time unit may correspond to at least one of a symbol, a symbol group, a time slot, or a time slot group.

[0205] In this regard, when performing PUSCH scheduling through DCI, the base station can indicate whether to send the corresponding PUSCH through STxMP, single panel or M-TRP repeated PUSCH. In this case, the terminal needs to have STxMP related capabilities and needs to pre-enable STxMP mode through high-level signaling (e.g., RRC signaling, etc.). For this indication, the existing SRS resource set indication field can be redefined and used, or a new DCI field can be introduced / defined.

[0206] In the present disclosure, when certain information is defined between a terminal and a base station, it may mean that the terminal and the base station know the corresponding information without separate signaling between the terminal and the base station; when configured between the terminal and the base station, it means sending / receiving the corresponding information through high-layer (e.g., RRC) signaling between the terminal and the base station; when indicated between the terminal and the base station, it means sending / receiving the corresponding information through low-layer (e.g., L1 (e.g., DCI / UCI), L2 (e.g., MAC-CE)) signaling.

[0207] CSI Improvements

[0208] The present disclosure relates to a CSI improvement method applicable to a high-speed terminal. For example, various examples of applying a time domain compression window to a PMI included in a CSI are described below.

[0209] In existing wireless communication systems, a codebook associated with PMI (e.g., a type II codebook) can support compressing PMIs of multiple subbands in the frequency domain and reporting them as one codebook. The present disclosure describes a method for compressing PMIs of multiple time units in the time domain and reporting them as one codebook (i.e., including them in one CSI report).

[0210] For example, the disclosure may include specific examples of the number of time units (or time instances), the interval of time units, the location of CSI reference resources, the window (or duration) of time units, etc. The disclosure may include examples of codebook parameters, including coefficients based on the time domain, granularity, etc. The disclosure may include examples of the relationship between time units and measurement restrictions of channel measurement resources (CMR) / interference measurement resources (IMR). The disclosure may include examples of criteria for time unit offsets.

[0211] Figure 8 is a diagram for describing an example of a CSI report transmission method of a terminal according to the present disclosure.

[0212] In S810 , the terminal may receive at least one CSI-RS from the network.

[0213] In S820 , the terminal may calculate a CQI based on a specific PMI, which is one of a plurality of PMIs corresponding to each of a plurality of time units.

[0214] In the following description, the term PMI may be replaced with a precoding matrix indicated by the PMI, or may include such a meaning.

[0215] One CQI may be associated with a specific time unit that is one of a plurality of time units. In addition, one CQI may be associated with a specific PMI among a plurality of PMIs. For example, a terminal may be configured to report at least one CQI, and one of these CQIs may be associated with a specific time unit / specific PMI.

[0216] For example, the particular time unit may correspond to a first or earliest time unit among a plurality of time units within the configured window.

[0217] For example, a specific time unit may correspond to a CSI reference resource.

[0218] For example, a first time unit among a plurality of time units within the configured window may correspond to a CSI reference resource.

[0219] For example, the specific PMI may be the first / earliest PMI (or a matrix indicated by the PMI) corresponding to a specific time unit (eg, the first / earliest time unit).

[0220] For example, the specific time unit may correspond to a time unit separated by a specific offset from a time unit (eg, a CSI reporting instance) in which a CSI report is transmitted.

[0221] For example, the duration of a time unit may be the same as the CSI-RS period. In addition, multiple time units may have the same duration. In other words, the duration of a first time unit and the duration of a second time unit may be the same. Therefore, multiple time instances may be located at the same interval in the time domain.

[0222] In S830, the terminal may send a CSI report to the network, where the CSI report includes codebook information corresponding to multiple PMIs and a CQI.

[0223] The codebook information corresponding to the plurality of PMIs may include a codebook index corresponding to each of the plurality of PMIs (or a combination of a plurality of codebook indices).

[0224] In addition to a CQI and codebook information, the CSI report may further include other information. The CSI report may be sent through one reporting instance, or may be sent through multiple reporting instances (ie, information included in one CSI report may be sent through different time points / channels).

[0225] Fig. 9 is a diagram for describing an example of a CSI report receiving method of a base station according to the present disclosure.

[0226] In S910 , the base station may send at least one CSI-RS to the terminal.

[0227] In S920, the base station may receive a CSI report from the terminal, the CSI report including a CQI and codebook information corresponding to a plurality of PMIs. The CQI may be calculated based on a specific PMI, the specific PMI being one of a plurality of PMIs corresponding to a plurality of time units, respectively.

[0228] Here, the specific examples of one CQI, multiple PMIs, and time units corresponding to the multiple PMIs are similar to those in the reference Figure 8 Those described are the same, so duplicate description is omitted.

[0229] Hereinafter, a specific example related to CSI reporting including codebook information of a plurality of PMIs corresponding to a plurality of time units according to the present disclosure is described.

[0230] For example, the following example may be applied to possible CSI improvements for high / medium terminal speeds. However, it does not limit the application target of the present disclosure, and the examples of the present disclosure may be applied to various purposes for more accurate and efficient CSI reporting.

[0231] For high / medium terminal speeds, aspects of Type II codebook improvements can be considered, and terminal reporting of time domain channel characteristics, such as Doppler shift or Doppler spread via TRS, can also be considered. These considerations can help base stations (e.g., gNBs) perform better link-level adjustments to time-varying channels due to high terminal mobility.

[0232] Specifically, the improved type II codebook including time domain compression can provide the base station with precoding information for multiple time instances (or time units) instead of precoding information for a single time instance (or time unit) that is susceptible to channel aging. Therefore, the base station can predict the time-varying channel direction and schedule a better MCS and precoder. At the same time, in addition to the existing CSI, by calculating and reporting Doppler information via TRS, the terminal can help the base station compensate for outdated CSI by using Doppler information. Therefore, the base station can predict the time-varying channel direction and schedule a better MCS and precoder.

[0233] In examples of the present disclosure, channel measurement improved by a Type II codebook, a time instance (or time unit) represented by a new codebook, a time domain basis (TD basis), etc. are described.

[0234] First, the channel measurement for type II codebook improvement is described.

[0235] Type II codebook improvement including time domain (TD) compression may require multiple channel measurements at the terminal side. In the operation where the terminal performs multiple channel measurements, the base station may enable / disable time domain channel / interference measurement restriction of the terminal.

[0236] When enabled, the terminal can measure the latest CMR / IMR no later than the CSI reference resource. Therefore, a single measurement can be used to estimate the channel in the CSI reference resource.

[0237] When disabled, the terminal can measure multiple CMR / IMR instances no later than the CSI reference resource. How to use multiple measurements to estimate the channel in the CSI reference resource can be performed in various ways according to the implementation of the terminal. In this way, for an unrestricted measurement configuration (i.e., the restriction is disabled), the terminal can use multiple measurements to calculate the CSI. When codebook improvements including TD compression are introduced, the terminal may need an unrestricted measurement configuration to calculate the PMI of multiple time instances.

[0238] In other words, for type II codebook improvements including TD compression, multiple channel measurements may be required on the terminal side. In addition, when the time restriction for channel measurement (e.g., timeRestrictionForChannelMeasurements parameter) is not configured, the terminal may use multiple channel / interference measurements to calculate the CSI including the improved codebook based on TD compression. In addition, when the time restriction (e.g., timeRestrictionForChannelMeasurements parameter) is configured, the terminal uses a single channel / interference measurement to calculate the CSI, so the improved codebook including TD compression may not be used.

[0239] Whether multiple channel measurements are possible depends not only on the above-mentioned time domain measurement restrictions, but also on the periodicity of CMR / IMR. For aperiodic (AP) CMR / IMR, there is only one CMR / IMR without periodicity, so only a single measurement is possible. Periodic (P) / semi-static (SP) CMR / IMR provides the terminal with multiple opportunities for channel / interference measurements. For example, if it is assumed that the minimum period is 4 time slots, it is necessary to check whether sufficiently frequent measurement instances are provided to the high-speed terminal. If the measurement instances are too sparse, the PMI accuracy may be reduced and the quality of TD compression may be reduced. Alternatively, if the measurement instances are too dense, the CSI-RS overhead may increase.

[0240] In other words, for AP CMR / IMR, there is only one CMR / IMR without periodicity, so only a single measurement is possible. In order for the P / SPSSI-RS to provide sufficient measurement time instances for the improved type II codebook including TD compression, a method for defining / configuring / indicating multiple time instances (or time units) is described below through a specific example of the present disclosure.

[0241] Next, a plurality of time instances (or time units) represented by an improved type II codebook including TD compression is described.

[0242] Similar to the existing type II codebook including frequency domain (FD) compression representing multiple PMIs of multiple subbands, the new type II codebook including TD compression can represent multiple PMIs of multiple time instances (or time units). Here, multiple time instances need to be determined / defined.

[0243] Fig.10 and Fig.11 is a diagram for describing an example of a CSI reference resource and a CSI reporting time unit according to the present disclosure.

[0244] The CSI including PMI / RI / CQI may represent a channel at a single time instance called a CSI reference resource. In other words, a single CQI included in the CSI may be calculated based on one PMI among multiple PMIs corresponding to multiple time units. Fig.10 In the example of , a time unit and a PMI associated with a CQI may be a first / earliest time unit and a first / earliest PMI corresponding to the CQI. Fig.11 In the example of , a time unit and a PMI associated with a CQI may be a final time unit and a final PMI (eg, the third of three PMIs) corresponding to the CQI.

[0245] A type II codebook including TD compression may provide a PMI for another time instance (eg, slot / symbol) as well as a PMI for a CSI reference resource. These time instances may be defined later or earlier in the time domain than the CSI reference resource.

[0246] Fig.10 The example shows a PMI that is no earlier than a plurality of time units of the CSI reference resource.

[0247] The terminal can calculate the PMI based on the CSI reference resource ref_rsc , the PMI ref_rsc It can be derived from the periodic CMR that is no later than the CSI reference resource. The terminal can calculate the PMI based on the resource that is τ time units later than the CSI reference resource. ref_rsc+τ , and the PMI is calculated based on the resource that is 2τ time units later than the CSI reference resource ref_rsc+2τ , the PMI ref_rsc+τ and PMI ref_rsc+2τ It can be predicted based on the periodic CMR no later than the CSI reference resource. For example, when assuming that the CSI reference resource is located in time slot l, the terminal can calculate the PMI based on the DL channel in time slot l+τ ref_rsc+τ And the PMI is calculated based on the DL channel in time slot l+2τ ref_rsc+2τ .

[0248] Therefore, PMI ref_rsc 、PMI ref_rsc+τ 、PMI ref_rsc+2τ …PMI feedback overhead can be reduced by using an improved type II codebook including TD compression for compression. Since the terminal is required to predict the DL channel at a time point after the CSI reference resource, the codebook including PMI at a future time point compared to the CSI reporting time point (e.g., time slot n) may be robust to channel aging and used by the base station for better link adjustment.

[0249] Fig.11 The example shows a PMI that is no later than a plurality of time units of a CSI reference resource.

[0250] The terminal can calculate the PMI based on the CSI reference resource ref_rsc , the PMI ref_rsc It can be derived from the periodic CMR that is no later than the CSI reference resource. The terminal can calculate the PMI based on the resource that is τ time units earlier than the CSI reference resource. ref_rsc－τ , and the PMI is calculated based on the resource 2τ time units earlier than the CSI reference resource ref_rsc－2τ , the PMI ref_rsc－τ and PMI ref_rsc－2τ It can be predicted based on the periodic CMR no later than the CSI reference resource. For example, when assuming that the CSI reference resource is located in time slot l, the terminal can calculate the PMI based on the DL channel in time slot l-τ ref_rsc－τ And the PMI is calculated based on the DL channel in time slot l-2τ ref_rsc－2τ .

[0251] Fig.11 The example of shows that there are periodic CMRs in CSI reference resource, CSI reference resource -τ and CSI reference resource -2τ. In other words, in Fig.11 In the example of , the interval of the multiple time units corresponding to each of the multiple PMIs is the same as τ, and τ may be the same as the period of the periodic CMR (eg, P / SP-CSI-RS). In addition, Fig.10 The example of also shows that the interval of the plurality of time units corresponding to each of the plurality of PMIs is the same as τ, and τ may be the same as the period of the periodic CMR (eg, P / SP-CSI-RS).

[0252] Therefore, PMI ref_rsc 、PMI ref_rsc－τ 、PMI ref_rsc－2τ…PMI feedback overhead can be reduced by using an improved type II codebook including TD compression for compression. Since the terminal does not need to predict the DL channel, the codebook including PMI at the past time point can have the same Fig.10 The example has lower terminal operation complexity than that of PMI. ref_rsc－τ 、PMI ref_rsc－2τ ...than PMI ref_rsc The more outdated (staler), the more difficult it may be for the base station to use them for better link adjustments or to obtain potential gains.

[0253] In other words, if Fig.10 and / or Fig.11 In the example of , multiple time instances represented by an improved type II codebook located before and / or after a CSI reference resource in the time domain may be defined / configured.

[0254] Next, the TD basis for type II codebook improvement is described.

[0255] As reference Fig.10 and Fig.11 As described, in order to cope with the channel aging effect caused by high mobility, the terminal can calculate multiple PMIs for multiple time instances. As the number of time instances associated with the PMI increases, the PMI feedback payload can increase linearly. Even when it is assumed that multiple PMIs share the same spatial domain (SD) basis and / or frequency domain (FD) basis, at least different coefficient values ​​must be reported for each PMI, which can occupy a major part of the payload.

[0256] Therefore, time domain compression using TD basis for coefficient values ​​may have the advantageous effect of reducing feedback overhead.When considering the existing type II codebook that independently selects SD basis and FD basis based on DFT matrix, TD basis may also be independently selected from SD basis and / or FD basis.

[0257] Alternatively, since the beam direction of each SD basis can be fully / partially aligned with or opposite to the moving direction of the terminal, each SD basis can experience a different level of time-varying channel. Considering this, if different TD bases can be selected for different SD bases, the codebook accuracy can be improved.

[0258] In other words, when the SD basis / FD basis specific TD basis selection is applied, the TD basis may be defined / configured by comprehensively considering aspects of reducing feedback overhead by using TD compression and performance gain.

[0259] Implementation Method 1

[0260] In reference Fig.10 and Fig.11 In the described example, the time instance (eg, CSI reporting window) of the channel represented by the PMI may be defined / configured as follows.

[0261] For example, information about the length of the CSI reporting window, the number of time instances (or time units) within the window, the interval between time instances, etc. may be predefined without signaling between the terminal and the base station, or may be configured to the terminal by signaling from the base station. The following description is made by assuming that the base station configures the window of time instances of the channel represented by the PMI to the terminal, but the examples of the present disclosure may also be applied to time instances that are predefined (or defined as default values) without signaling from the base station.

[0262] For example, the base station may signal the window of time instances to the terminal through a parameter included in RRC signaling for codebook configuration.

[0263] The number of time instances to be represented by the PMI (ie, information about the number of time instances within the window) may be configured / indicated to the terminal. Fig.10 and Fig.11 In the example of , it can be assumed that the number of time instances is 3. The number of time instances can be configured by considering the time-varying nature of the channel, and for this purpose, the terminal can report its own speed information, Doppler information (e.g., Doppler shift / Doppler spread), etc. to the base station. Alternatively, the terminal can report the preferred number of time instances to the base station based on its own speed or Doppler information, and the base station can approve or consider it, select the number of time instances to be finally applied and notify it to the terminal. Additionally or alternatively, the terminal can report candidate values ​​of the number of time instances as capability information to the network.

[0264] Regarding the intervals between time instances (i.e., Fig.10 and Fig.11 The information of τ in the example of τ can be configured / indicated to the terminal. The value of τ can be configured by considering the time-varying nature of the channel, and for this purpose, the terminal can report its own speed information, Doppler information (e.g., Doppler shift / Doppler spread), etc. to the base station. Alternatively, the terminal can report the preferred value of τ to the base station based on its own speed or Doppler information, and the base station can approve or consider it, select the τ value that will be applied last and notify it to the terminal. For example, the value of τ can be represented by an absolute time length, a number of time slots, a number of OFDM symbols, etc. In addition, the terminal can report the candidate value of the value of τ to the network as capability information.

[0265] Additionally or alternatively, as in the above example, the interval between time instances can be configured to be the same as the periodic CMR (or the interval or period between P / SP-CSI-RS). In addition, the interval between time instances can also be referred to as the duration of each time instance. In other words, information about the interval between time instances or the duration of time instances can be configured / indicated to the terminal separately, or the same value as the period provided by a specific CSI-RS configuration can be configured / indicated to the terminal.

[0266] The order of CSI reference resources in a time instance may be configured / indicated to the terminal.

[0267] exist Fig.10 In the example, the first / earliest time instance may correspond to the CSI reference resource. Fig.10 An example may correspond to a case where the offset between the CSI reference resource and the time instance is 0. For example, the base station may configure / indicate information about the offset between the CSI reference resource and the time instance to the terminal. When the CSI reference resource corresponds to the first / earliest time instance, at least one remaining time instance may be located after the CSI reference resource in the time domain. In addition, as described above, when the CSI reference resource corresponds to the first / earliest time unit (e.g., time slot) within a window, a single CQI may be associated with a first / earliest time unit and a (i.e., first / earliest) PMI corresponding thereto.

[0268] exist Fig.11 In the example, the final time instance may correspond to the CSI reference resource. Fig.11 An example may correspond to a case where the offset between the CSI reference resource and the time instance is 2 (or 2τ). For example, the base station may configure / indicate information about the offset between the CSI reference resource and the time instance to the terminal. When the CSI reference resource corresponds to the final time instance, at least one remaining time instance may be located before the CSI reference resource in the time domain. In addition, as described above, when the CSI reference resource corresponds to the final time unit (e.g., time slot) within the window, a single CQI may be associated with a final time unit and a PMI (e.g., the third of three PMIs) corresponding thereto.

[0269] In the above example, the offset of the time instance (i.e., the time domain interval with the CSI reference resource) can be configured by considering the time-varying characteristics of the channel, and for this purpose, the terminal can report its own speed information, Doppler information (e.g., Doppler shift / Doppler spread), etc. to the base station. Alternatively, the terminal can report the preferred time instance offset to the base station based on its own speed or Doppler information, and the base station can approve or consider it, select the time instance offset to be finally applied and notify it to the terminal.

[0270] For example, a capability may be defined related to a time instance offset in which a CSI reference resource may be configured as a final time instance within a window (e.g. Fig.11 ) and the ability that the CSI reference resource can be configured as a time instance offset of the first time instance within the window (as shown Fig.10 As shown). In other words, some terminals may only support the former capability, other terminals may only support the latter capability, and other terminals may support both the former and the latter capability. These terminal capabilities may be reported to the network. The former capability does not require channel prediction, so the terminal implementation is simple, while the latter capability requires channel prediction, so the terminal implementation may be complex. Specifically, for the latter case, the terminal may additionally report to the network a configurable minimum value of a time instance offset (i.e., related to the prediction performance of the terminal) or a candidate for a configurable time instance offset value (i.e., related to the prediction performance of the terminal). For example, when the minimum value of the time instance offset is small, more predictions must be performed, which may increase the complexity of the terminal implementation.

[0271] In the above example, the position of time instances in the time domain (e.g., a grid) can be defined / configured by the number and interval of time instances, and the time slots / symbols at which the grid of corresponding time instances is located can be defined / determined by the time instance offset of the CSI reference resource.

[0272] Additionally or alternatively, the position (e.g., grid) of the time instance on the time domain can be defined / configured by defining / configuring the length of the window of the time instance as the number of time units (e.g., time slots / symbols) within the corresponding window and defining / configuring the number of time instances. In other words, time instances separated by the same interval as the number of time instances within the window can be determined. Alternatively, time instances with the same duration within the window can be determined. For example, when the length of the window is defined as 3 time slots and the number of time instances is 3, the time instance grid can be represented as 3 consecutive time slots. In other words, the duration of each time instance can be 1 time slot.

[0273] In this case, when the time instance offset value is given as 0, the final time instance may be determined as slot index l, slot index l+1, and slot index l+2 corresponding to the CSI reference resource slot.

[0274] The above example corresponds to the case where the time instances are configured at the same interval (or the duration of each time instance is the same). Additionally or alternatively, when the time-varying characteristics of the channel vary over time and are predictable, it may be inefficient to allocate the time instances at the same interval (or the same duration). For example, when N time instances are configured, it is assumed that the time-varying characteristics of the channel are strong in front of the entire duration represented by the PMI (ie, earlier time), and the time-varying characteristics of the channel are weak behind the entire duration (ie, later time). In this case, the time instances can be arranged more densely in front of the entire duration (ie, with narrow intervals or short durations), and the time instances can be arranged more sparsely behind the entire duration (ie, with wide intervals or long durations). For example, when the CSI reference resource (time slot l) is located in the first time instance, the second time instance can be located in time slot l+1, the third time instance can be located in time slot l+2, and the fourth time instance can be located in time slot l+5. Therefore, the compression ratio and accuracy of TD compression can be improved.

[0275] In this way, the intervals of the time instances within the window may be the same interval (or the same duration) or may not be the same interval (or different durations). In this regard, the terminal may send information related to the location of the time instance to the network (along with the CSI report). Alternatively, the base station may configure / indicate information related to the location of the time instance to the terminal. For example, the base station may provide the terminal with information related to the location of the time instance via a UL scheduling DCI that triggers an APCSI report.

[0276] Among the information / parameters related to the time instances as described above (e.g., window length, the number of time instances within the window, the interval between time instances, the time instance duration, the time instance position, etc.), some parameters may be fixed (i.e., no signaling is required between the terminal and the base station), and the remaining parameters may be configured by the base station to the terminal or may be reported by the terminal to the base station.

[0277] According to the time instance configured as described above, the parameters of the TD compression codebook may be different. For example, due to the small number of time instances within the same window length, or the large interval between time instances (or the duration of the time instance), or the long window length, it is necessary to perform TD compression for a longer time. The TD basis candidates applicable to these various situations may vary. For example, when the TD basis candidate is constructed based on the DFT matrix, the DFT matrix may be constructed as a function of the number of time instances or the interval between time instances. In addition, the granularity (or configurable range of granularity) of the coefficients (e.g., amplitude, phase) applied when the SD / FD / TD basis is linearly combined may also be adjusted. For example, when the number of time instances increases, the number of coefficients may increase, and in order to offset the increase in its overhead, the granularity of the coefficients may increase and the number of candidate values ​​that can be represented within the coefficient value range may be reduced. In addition, in the type II codebook, instead of reporting all coefficients, some coefficients may be configured to zero, and only the values ​​of non-zero coefficients may be reported. The configuration (or configurable range) of the number of these zero coefficients may also vary according to the number of time instances or the time interval between time instances.

[0278] The base station may provide information to the terminal through RRC signaling, such as whether to configure the time instance as a CSI reference resource and how to Fig.10 resources (or time slots) located later in the time domain or whether to configure the time instance as a CSI reference resource and Fig.11 The information of the resource (or time slot) located earlier in the time domain.

[0279] In addition, the measurement restriction interval of CMR / IMR can be determined relative to the PMI time instance. For example, when time slot l, time slot l-τ and time slot l-2τ are configured as follows Fig.11 When the time instance (or CSI reporting window) represented by the PMI in , there may be a restriction to measure the DL channel of time slot l by using CMR / IMR existing in time slot l or before time slot l and time slot l-τ or after time slot l-τ, there may be a restriction to measure the DL channel of time slot l-τ by using CMR / IMR existing in time slot l-τ or before time slot l-τ and time slot l-2τ or after time slot l-2τ, and there may be a restriction to measure the DL channel of time slot l-2τ by using CMR / IMR existing in time slot l-2τ or before time slot l-2τ and time slot l-3τ or after time slot l-3τ (or existing before time slot l-2τ, without any restriction on the time boundary after it). Through this restriction, the base station can control the implementation of channel / interference measurement of the terminal for CSI calculation. As a result, the base station receives CSI calculated by a common implementation from multiple terminals, whereby the base station can unify the process of compensating CSI for time-varying channels and calculating PMI / MCS, etc.

[0280] Implementation Method 2

[0281] In the above examples, the time instance offset is described as a relative position with respect to the CSI reference resource.

[0282] Additionally or alternatively, the CSI reporting time point (eg, Fig.10 and Fig.11 The time instance offset (or the location of the CSI reference resource included in the time offset) is defined / configured by the time slot n in the time instance offset.

[0283] Additionally or alternatively, the time instance offset (or the location of the CSI reference resource included in the time offset) may be defined / configured based on the final time unit of the CSI measurement window (different from the CSI reporting window). The CSI measurement window may refer to a time interval (or time unit) during which a channel / interference may be measured for CSI calculation, and the CSI reporting window may refer to a time interval (or time unit) corresponding to a channel represented by the CSI.

[0284] In the above example, the time instance offset may be configured as a negative value or a value greater than or equal to the number of time instances. When the time instance offset is configured as a relative position relative to the CSI reference resource, if the time instance offset is negative, the time instance may only exist at a future time point compared to the CSI reference resource. If the time instance offset is configured as a value greater than or equal to the number of time instances, the time instance may only exist at a past time point compared to the CSI reference resource.

[0285] The possible range of the time instance offset may be reported by the terminal to the base station (eg, as capability information). The base station may also configure / indicate the time instance offset value to the terminal by considering the reported information from the terminal (eg, within the range reported by the terminal).

[0286] The values ​​of various information / parameters provided to the terminal as described in the above examples may be configured / indicated by (utilizing) the AP CSI report trigger field of the UL scheduled DCI for AP CSI reporting, by parameters in the CSI-ReportConfig IE, and / or by PMI codebook related configuration information.

[0287] The maximum value of each of the number of time instances and the time instance interval may be reported by the terminal to the base station (e.g., as capability information). When the number of time instances or the time instance interval is large, the amount of calculation required by the terminal for CSI calculation may increase. Therefore, the terminal may report to the base station the maximum value of the number of time instances and / or the time instance interval that affects the amount of CSI calculation. The base station may configure / indicate the number of time instances and / or the time instance interval to the terminal by considering the maximum value reported from the terminal (e.g., within a range not exceeding the maximum value).

[0288] Additionally or alternatively, the terminal may report information about a combination of the number of time instances and the time instance intervals to the base station (e.g., as terminal capability information). For example, the terminal may separately report a combination of how many time slots there are in the maximum interval when there are N1 time instances, and a combination of how many time slots there are in the maximum interval when there are N2 time instances. Alternatively, the terminal may separately report a combination of the number of time instances when the maximum interval is S1 time slots, and a combination of the number of time instances when the maximum interval is S2 time slots. As the number of time instances increases, the maximum interval supported by the terminal may decrease (or as the maximum interval increases, the number of time instances may decrease), so this reporting method may be effective.

[0289] Even when the time instance is defined / configured by using a window of the time instance instead of the interval of the time instance, the reporting method can be applied by replacing the interval of the above-mentioned time instance with the length of the window of the time instance. For example, the terminal can report capability information about the length of the window and / or the number of time instances to the base station. The base station can also provide configuration / indication information about the length of the window and / or the number of time instances to the terminal. For example, when the time instances have the same interval (or the same duration), the length of the window can be defined / configured as the product of the interval of the time instance (or the duration of the time instance) and the number of time instances.

[0290] General devices to which the present disclosure can be applied

[0291] Fig.12 A block diagram of a wireless communication device according to an embodiment of the present disclosure is illustrated.

[0292] Reference Fig.12 , the first wireless device 100 and the second wireless device 200 can send and receive wireless signals through various radio access technologies (e.g., LTE, NR).

[0293] The first wireless device 100 may include 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 control the memory 104 and / or the transceiver 106, and may be configured to implement the description, function, process, suggestion, method and / or operation flowchart disclosed in the present disclosure. For example, the processor 102 may transmit a wireless signal including the first information / signal through the transceiver 106 after generating the first information / signal by processing the information in the memory 104. In addition, the processor 102 may receive a wireless signal including the second information / signal through the transceiver 106, and then store the information obtained by the signal processing of the second information / signal in the memory 104. The memory 104 may be connected to the processor 102 and may store various information related to the operation of the processor 102. For example, the memory 104 may store software codes including commands for executing all or part of the processing controlled by the processor 102 or for executing the description, function, process, suggestion, method and / or operation flowchart disclosed in the present disclosure. Here, the processor 102 and the memory 104 may be part of a communication modem / circuit / chip designed to implement wireless communication technology (e.g., LTE, NR). The transceiver 106 may be connected to the processor 102 and may send and / or receive wireless signals through one or more antennas 108. The transceiver 106 may include a transmitter and / or a receiver. The transceiver 106 may be used in conjunction with an RF (radio frequency) unit. In the present disclosure, a wireless device may refer to a communication modem / circuit / chip.

[0294] The second wireless device 200 may include one or more processors 202 and 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 control the memory 204 and / or the transceiver 206, and may be configured to implement the description, function, process, suggestion, method and / or operation flowchart disclosed in the present disclosure. For example, the processor 202 may generate third information / signal by processing the information in the memory 204, and then transmit the wireless signal including the third information / signal through the transceiver 206. In addition, the processor 202 may receive the wireless signal including the fourth information / signal through the transceiver 206, and then store the information obtained by the signal processing of the fourth information / signal in the memory 204. The memory 204 may be connected to the processor 202 and may store various information related to the operation of the processor 202. For example, the memory 204 may store software codes including commands for executing all or part of the processing controlled by the processor 202 or for executing the description, function, process, suggestion, method and / or operation flowchart disclosed in the present disclosure. Here, the processor 202 and the memory 204 may be part of a communication modem / circuit / chip designed to implement wireless communication technology (e.g., LTE, NR). The transceiver 206 may be connected to the processor 202 and may send and / or receive wireless signals through one or more antennas 208. The transceiver 206 may include a transmitter and / or a receiver. The transceiver 206 may be used in conjunction with an RF unit. In the present disclosure, a wireless device may refer to a communication modem / circuit / chip.

[0295] In the following, the hardware elements of the wireless device 100, 200 will be described in more detail. Without limitation thereto, one or more protocol layers may be implemented by one or more processors 102, 202. For example, one or more processors 102, 202 may implement one or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP, RRC, SDAP). One or more processors 102, 202 may generate one or more PDUs (protocol data units) and / or one or more SDUs (service data units) according to the descriptions, functions, processes, suggestions, methods, and / or operational flowcharts disclosed in the present disclosure. One or more processors 102, 202 may generate messages, control information, data, or information according to the descriptions, functions, processes, suggestions, methods, and / or operational flowcharts included in the present disclosure. One or more processors 102, 202 may generate a signal (e.g., a baseband signal) including a PDU, SDU, message, control information, data, or information according to the functions, procedures, suggestions, and / or methods disclosed in the present disclosure to provide it to one or more transceivers 106, 206. One or more processors 102, 202 may receive a signal (e.g., a baseband signal) from one or more transceivers 106, 206 according to the descriptions, functions, procedures, suggestions, methods, and / or operational flow charts disclosed in the present disclosure, and obtain the PDU, SDU, message, control information, data, or information.

[0296] One or more processors 102, 202 may be referred to as controllers, microcontrollers, microprocessors, or microcomputers. One or more processors 102, 202 may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more ASICs (Application Specific Integrated Circuits), one or more DSPs (Digital Signal Processors), one or more DSPDs (Digital Signal Processing Devices), one or more PLDs (Programmable Logic Devices), or one or more FPGAs (Field Programmable Gate Arrays) may be included in one or more processors 102, 202. The descriptions, functions, processes, suggestions, methods, and / or operational flow charts disclosed in the present disclosure may be implemented using firmware or software, and the firmware or software may be implemented to include modules, processes, functions, and the like. Firmware or software configured to execute the descriptions, functions, processes, suggestions, methods, and / or operational flow charts disclosed in the present disclosure may be included in one or more processors 102, 202, or may be stored in one or more memories 104, 204 and driven by one or more processors 102, 202. The descriptions, functions, processes, suggestions, methods and / or operational flow charts disclosed in the present disclosure may be implemented by using firmware or software in the form of codes, commands and / or command sets.

[0297] One or more memories 104, 204 may be connected to one or more processors 102, 202 and may store data, signals, messages, information, programs, codes, instructions, and / or commands in various forms. One or more memories 104, 204 may be configured with ROM, RAM, EPROM, flash memory, hard drive, registers, cache memory, computer-readable storage media, and / or combinations thereof. One or more memories 104, 204 may be located inside and / or outside one or more processors 102, 202. In addition, one or more memories 104, 204 may be connected to one or more processors 102, 202 via various technologies such as wired or wireless connections.

[0298] One or more transceivers 106, 206 may send user data, control information, wireless signals / channels, etc. mentioned in the method and / or operation flow chart 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. mentioned in the description, function, process, suggestion, method and / or operation flow chart disclosed in the present disclosure from one or more other devices. For example, one or more transceivers 106, 206 may be connected to one or more processors 102, 202 and may send and receive wireless signals. For example, one or more processors 102, 202 may control one or more transceivers 106, 206 to send user data, control information or wireless signals to one or more other devices. In addition, 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. In addition, one or more transceivers 106, 206 may be connected to one or more antennas 108, 208, and one or more transceivers 106, 206 may be configured to send and receive user data, control information, wireless signals / channels, etc. mentioned in the description, functions, processes, suggestions, methods, and / or operation flow charts, etc. disclosed in the present disclosure through one or more antennas 108, 208. In the present disclosure, one or more antennas may be multiple physical antennas or multiple logical antennas (e.g., antenna ports). One or more transceivers 106, 206 may convert received wireless signals / channels, etc. from RF band signals into baseband signals to process received user data, control information, wireless signals / channels, etc. by using one or more processors 102, 202. One or more transceivers 106, 206 may convert user data, control information, wireless signals / channels, etc. processed by using one or more processors 102, 202 from baseband signals into RF band signals. Thus, one or more of the transceivers 106 , 206 may include (analog) oscillators and / or filters.

[0299] The above-mentioned embodiments are to combine the elements and features of the present disclosure in a predetermined form. Unless otherwise explicitly mentioned, each element or feature should be considered as optional. Each element or feature can be implemented in a form that is not combined with other elements or features. In addition, the embodiments of the present disclosure may include combined partial elements and / or features. The order of the operations described in the embodiments of the present disclosure may be changed. Some elements or features of an embodiment may be included in other embodiments, or may be replaced by corresponding elements or features of other embodiments. Obviously, the embodiments may include claims that do not have a clear reference relationship in the combined claims, or may be included as new claims by modification after application.

[0300] It is clear to those skilled in the relevant art that the present disclosure can be implemented in other specific forms within the scope of the essential features of the present disclosure. Therefore, the above detailed description should not be interpreted restrictively in every aspect, but should be considered as illustrative. The scope of the present disclosure should be determined by the reasonable interpretation of the attached claims, and all changes within the equivalent scope of the present disclosure are included in the scope of the present disclosure.

[0301] The scope of the present disclosure includes software or machine executable commands (e.g., operating systems, applications, firmware, programs, etc.) that perform operations in a device or computer according to the methods of various embodiments, and non-transitory computer-readable media that enable software or commands, etc. to be stored and executable in a device or computer. Commands that can be used to program a processing system that performs the features described in the present disclosure can be stored in a storage medium or a computer-readable storage medium, and the features described in the present disclosure can be implemented by using a computer program product that includes such a storage medium. The storage medium may include a high-speed random access memory, such as DRAM, SRAM, DDRRAM, or other random access solid-state storage devices, but is not limited thereto, and it 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. The memory optionally includes one or more storage devices located away from the processor. The memory, or alternatively, the non-volatile memory device in the memory includes a non-transitory computer-readable storage medium. The features described in this disclosure may be stored in any machine-readable medium to control the hardware of a processing system, and may be integrated into software and / or firmware that allows the processing system to interact with other mechanisms using the results from the 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.

[0302] Here, the wireless communication technology implemented in the wireless devices 100 and 200 of the present disclosure may include narrowband Internet of Things for low-power communication, as well as LTE, NR and 6G. Here, for example, NB-IoT technology may be an example of LPWAN (Low Power Wide Area Network) technology, which may be implemented in standards such as LTE Cat NB1 and / or LTE Cat NB2 and is not limited to the above 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 LTE-M technology. Here, for example, LTE-M technology may be an example of LPWAN technology and may be referred to as various names such as eMTC (enhanced machine type communication). For example, LTE-M technology may be implemented in at least any one of various standards, including 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, etc., and is not limited to the above names. Additionally or alternatively, the wireless communication technology implemented in the wireless devices 100, 200 of the present disclosure may include at least any one of ZigBee, Bluetooth, and a low power wide area network (LPWAN) considering low power communication, and is not limited to the above names. For example, ZigBee technology can generate a PAN (Personal Area Network) related to small / low power digital communication based on various standards (e.g., IEEE 802.15.4, etc.), and can be called various names.

[0303] Industrial Applicability

[0304] The method proposed in the present disclosure is mainly described based on examples applied to 3GPP LTE / LTE-A and 5G systems, but can also be applied to various wireless communication systems other than 3GPP LTE / LTE-A and 5G systems.

Claims

1. A method performed by a terminal in a wireless communication system, the method comprising: receiving at least one channel state information-reference signal CSI-RS from a network; Calculating a channel quality indicator CQI based on a specific precoding matrix indicator PMI, wherein the specific PMI is one of a plurality of PMIs respectively corresponding to a plurality of time units; as well as sending a CSI report to the network, the CSI report including the one CQI and codebook information corresponding to the multiple PMIs, The one CQI is associated with the specific PMI and a specific time unit that is one of the multiple time units.

2. The method according to claim 1, wherein: The specific time unit is a first time unit among the plurality of time units within a configuration window.

3. The method according to claim 1, wherein: The specific time unit corresponds to a CSI reference resource.

4. The method according to claim 1, wherein: The specific PMI corresponds to the specific time unit.

5. The method according to claim 1, wherein: The specific time unit corresponds to a specific offset relative to a time unit at which the CSI report is transmitted.

6. The method according to claim 1, wherein: A first time unit among the plurality of time units within the configuration window corresponds to a CSI reference resource.

7. The method according to claim 1, wherein: The duration of the time unit is the same as the period of the CSI reference signal RS.

8. The method according to claim 1, wherein: The plurality of time units have the same duration.

9. A terminal in a wireless communication system, the terminal comprising: at least one transceiver; as well as at least one processor connected to the at least one transceiver, Wherein, the at least one processor is configured to: receiving, by the at least one transceiver, at least one channel state information-reference signal CSI-RS from a network; calculating a channel quality indicator CQI based on a specific precoding matrix indicator PMI, wherein the specific PMI is one of a plurality of PMIs respectively corresponding to a plurality of time units; and Sending a CSI report to the network through the at least one transceiver, wherein the CSI report includes the one CQI and codebook information corresponding to the multiple PMIs, The one CQI is associated with the specific PMI and a specific time unit that is one of the multiple time units.

10. A method performed by a base station in a wireless communication system, the method comprising: Sending at least one channel state information-reference signal CSI-RS to the terminal; as well as receiving a CSI report from the terminal, the CSI report including a channel quality indicator CQI and codebook information corresponding to the plurality of precoding matrix indicators PMIs, The one CQI is calculated based on a specific PMI, and the specific PMI is one of a plurality of PMIs corresponding to a plurality of time units respectively. The one CQI is associated with the specific PMI and a specific time unit that is one of the multiple time units.

11. A base station in a wireless communication system, the base station comprising: at least one transceiver; as well as at least one processor connected to the at least one transceiver, Wherein, the at least one processor is configured to: Sending at least one channel state information-reference signal CSI-RS to the terminal through the at least one transceiver; and receiving a CSI report from the terminal through the at least one transceiver, the CSI report including a channel quality indicator CQI and codebook information corresponding to the plurality of precoding matrix indicators PMIs, The one CQI is calculated based on a specific PMI, and the specific PMI is one of a plurality of PMIs corresponding to a plurality of time units respectively. The one CQI is associated with the specific PMI and a specific time unit that is one of the multiple time units.

12. A processing unit configured to control a terminal in a wireless communication system, the processing unit comprising: at least one processor; as well as At least one computer memory, the at least one computer memory being operatively connected to the at least one processor and storing instructions for executing the method according to any one of claims 1 to 7 upon being executed by the at least one processor.

13. At least one non-transitory computer-readable medium storing at least one instruction, wherein: The at least one instruction is executed by at least one processor to control a device in a wireless communication system to perform the method according to any one of claims 1 to 7.

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