Method and apparatus for transmitting and receiving group common downlink channel in wireless communication system

Abstract

Disclosed are a method and an apparatus for transmitting and receiving a group common downlink channel in a wireless communication system. A method performed by a terminal in a wireless communication system according to an embodiment of the present disclosure may comprise the steps of: performing measurement of multiple spatial parameters so as to select a specific spatial parameter; performing uplink transmission based on the specific spatial parameter; and receiving multicast-based downlink transmission on the basis of the specific spatial parameter. Here, the terminal is in an inactive mode or an idle mode based on radio resource control (RRC), and the uplink transmission may include at least one of transmission of a preamble for random access and transmission of an uplink data channel.

Description

Method and device for transmitting and receiving a group common downlink channel in a wireless communication system

[0001] The present disclosure relates to a wireless communication system, and more particularly, to a method and device for transmitting and receiving a group common downlink channel in a wireless communication system.

[0002] Mobile communication systems were developed to provide voice services while ensuring user activity. However, they have expanded beyond voice to include data services. Currently, explosive growth in traffic is leading to resource shortages and users' demand for higher-speed services, necessitating a more advanced mobile communication system.

[0003] Next-generation mobile communication systems must support explosive data traffic growth, dramatically increasing data rates per user, a vastly increased number of connected devices, ultra-low end-to-end latency, and high energy efficiency. To achieve these goals, various technologies are being studied, including dual connectivity, massive multiple input multiple output (MIMO), in-band full duplex, non-orthogonal multiple access (NOMA), super wideband support, and device networking.

[0004] The technical problem of the present disclosure is to provide a method and device for transmitting and receiving a group common downlink channel in a wireless communication system.

[0005] The technical problem of the present disclosure is to provide a method and device for a terminal in an inactive mode (e.g., RRC_INACTIVE mode) to receive a multicast downlink channel in a wireless communication system.

[0006] The technical problems to be achieved in the present disclosure are not limited to the technical problems mentioned above, and other technical problems not mentioned will be clearly understood by a person having ordinary skill in the technical field to which the present disclosure belongs from the description below.

[0007] A method performed by a terminal in a wireless communication system according to one aspect of the present disclosure may include: performing measurements on a plurality of spatial parameters to select a specific spatial parameter; performing uplink transmission based on the specific spatial parameter; and receiving multicast-based downlink transmission based on the specific spatial parameter. Here, the terminal is in an idle mode or an inactive mode based on radio resource control (RRC), and the uplink transmission may include at least one of transmission of a preamble for random access or transmission of an uplink data channel.

[0008] A method performed by a base station in a wireless communication system according to an additional aspect of the present disclosure may include: receiving an uplink transmission based on a specific spatial parameter selected through measurements of a plurality of spatial parameters; and performing a multicast-based downlink transmission based on the specific spatial parameter. Here, the terminal is in an idle mode or an inactive mode based on radio resource control (RRC), and the uplink transmission may include at least one of transmission of a preamble for random access or transmission of an uplink data channel.

[0009] According to an embodiment of the present disclosure, a method and device for transmitting and receiving a group common downlink channel in a wireless communication system can be provided.

[0010] According to an embodiment of the present disclosure, a method and apparatus for receiving a multicast downlink channel by a terminal in an inactive mode (e.g., RRC_INACTIVE mode) in a wireless communication system can be provided.

[0011] According to an embodiment of the present disclosure, there is a technical effect in which a terminal in an inactive mode in a wireless communication system selects an optimal beam, and transmission and reception of a multicast downlink channel can be performed based on the selected beam.

[0012] The effects that can be obtained from the present disclosure are not limited to the effects mentioned above, and other effects that are not mentioned will be clearly understood by a person having ordinary skill in the art to which the present disclosure pertains from the description below.

[0013] The accompanying drawings, which are incorporated in and are part of the detailed description to aid in understanding the present disclosure, provide embodiments of the present disclosure and, together with the detailed description, describe the technical features of the present disclosure.

[0014] Figure 1 illustrates the structure of a wireless communication system to which the present disclosure can be applied.

[0015] FIG. 2 illustrates a frame structure in a wireless communication system to which the present disclosure can be applied.

[0016] FIG. 3 illustrates a resource grid in a wireless communication system to which the present disclosure can be applied.

[0017] FIG. 4 illustrates a physical resource block in a wireless communication system to which the present disclosure can be applied.

[0018] FIG. 5 illustrates a slot structure in a wireless communication system to which the present disclosure can be applied.

[0019] FIG. 6 illustrates 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 same.

[0020] FIG. 7 illustrates a multi-TRP transmission method in a wireless communication system to which the present disclosure can be applied.

[0021] FIG. 8 illustrates a HARQ-ACK process for downlink data in a wireless communication system to which the present disclosure can be applied.

[0022] FIG. 9 illustrates transmission and reception of group common PDCCH / PDSCH and HARQ-ACK applicable to the present disclosure.

[0023] FIG. 10 illustrates an operation method of a terminal according to an embodiment of the present disclosure.

[0024] FIG. 11 illustrates an operation method of a base station according to an embodiment of the present disclosure.

[0025] FIG. 12 illustrates a block diagram of a wireless communication device according to one embodiment of the present disclosure.

[0026] Hereinafter, preferred embodiments of the present disclosure will be described in detail with reference to the accompanying drawings. The detailed description set forth below, together with the accompanying drawings, is intended to explain exemplary embodiments of the present disclosure and is not intended to represent the only embodiments in which the present disclosure may be practiced. The following detailed description includes specific details to provide a thorough understanding of the present disclosure. However, one of ordinary skill in the art will appreciate that the present disclosure may be practiced without these specific details.

[0027] In some cases, to avoid obscuring the concepts of the present disclosure, known structures and devices may be omitted or illustrated in block diagram form focusing on the core functions of each structure and device.

[0028] In the present disclosure, when a component is said to be "connected," "coupled," or "connected" to another component, this may include not only a direct connection but also an indirect connection in which another component exists between them. Furthermore, the terms "comprises" or "has" in the present disclosure specify the presence of the mentioned features, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or groups thereof.

[0029] In this disclosure, terms such as “first,” “second,” etc. are used only to distinguish one component from another and are not used to limit the components, and do not limit the order or importance between the components unless specifically stated otherwise. Accordingly, within the scope of this disclosure, a first component in one embodiment may be referred to as a second component in another embodiment, and similarly, a second component in one embodiment may be referred to as a first component in another embodiment.

[0030] The terminology used herein is for the purpose of describing particular embodiments and is not intended to limit the scope of the claims. As used in the description of the embodiments and the appended claims, the singular forms "a," "an," and "the" are intended to include the plural forms as well, unless the context clearly dictates otherwise. The term "and / or" as used herein may refer to any one of the associated enumerated items, or is meant to refer to and encompass any and all possible combinations of two or more of them. Furthermore, the use of " / " between words in this disclosure has the same meaning as "and / or" unless otherwise stated.

[0031] The present disclosure describes a wireless communication network or a wireless communication system, and an operation performed in a wireless communication network may be performed in a process of controlling the network and transmitting or receiving a signal from a device (e.g., a base station) that manages the wireless communication network, or may be performed in a process of transmitting or receiving a signal to or between terminals connected to the wireless network.

[0032] In the present disclosure, transmitting or receiving a channel means transmitting or receiving information or a signal through the channel. For example, transmitting a control channel means transmitting control information or a signal through the control channel. Similarly, transmitting a data channel means transmitting data information or a signal through the data channel.

[0033] Hereinafter, downlink (DL) refers to communication from a base station to a terminal, and uplink (UL) refers to communication from a terminal to a base station. In downlink, a transmitter may be part of a base station, and a receiver may be part of a terminal. In uplink, a transmitter may be part of a terminal, and a receiver may be part of a base station. A base station may be expressed as a first communication device, and a terminal may be expressed as a second communication device. A base station (BS) may be replaced by terms such as a fixed station, Node B, eNB (evolved-NodeB), gNB (Next Generation NodeB), BTS (base transceiver system), access point (AP: Access Point), network (5G network), AI (Artificial Intelligence) system / module, RSU (road side unit), robot, drone (UAV: Unmanned Aerial Vehicle), AR (Augmented Reality) device, VR (Virtual Reality) device, etc.In addition, the terminal may be fixed or mobile, and may be replaced with terms such as UE (User Equipment), MS (Mobile Station), UT (user terminal), MSS (Mobile Subscriber Station), SS (Subscriber Station), AMS (Advanced Mobile Station), WT (Wireless terminal), MTC (Machine-Type Communication) device, M2M (Machine-to-Machine) device, D2D (Device-to-Device) device, vehicle, RSU (road side unit), robot, AI (Artificial Intelligence) module, UAV (Unmanned Aerial Vehicle), AR (Augmented Reality) device, VR (Virtual Reality) device, etc.

[0034] The following technologies can be used in various wireless access systems, such as CDMA, FDMA, TDMA, OFDMA, and SC-FDMA. CDMA can be implemented using wireless technologies such as UTRA (Universal Terrestrial Radio Access) or CDMA2000. TDMA can be implemented using wireless technologies such as GSM (Global System for Mobile communications) / GPRS (General Packet Radio Service) / EDGE (Enhanced Data Rates for GSM Evolution). OFDMA can be implemented using wireless technologies such as IEEE 802.11 (Wi-Fi), IEEE 802.16 (WiMAX), IEEE 802-20, and E-UTRA (Evolved UTRA). UTRA is part of UMTS (Universal Mobile Telecommunications System). 3GPP (3rd Generation Partnership Project) LTE (Long Term Evolution) is a part of E-UMTS (Evolved UMTS) that uses E-UTRA, and LTE-A (Advanced) / LTE-A pro is an evolved version of 3GPP LTE. 3GPP NR (New Radio or New Radio Access Technology) is an evolved version of 3GPP LTE / LTE-A / LTE-A pro.

[0035] For clarity, 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 thereto. LTE refers to technology after 3GPP TS (Technical Specification) 36.xxx Release 8. Specifically, LTE technology after 3GPP TS 36.xxx Release 10 is referred to as LTE-A, and LTE technology after 3GPP TS 36.xxx Release 13 is referred to as LTE-A pro. 3GPP NR refers to technology after TS 38.xxx Release 15. LTE / NR may be referred to as a 3GPP system. "xxx" refers to a standard document detail number. LTE / NR may be collectively referred to as a 3GPP system. For background technology, terms, abbreviations, etc. used in the description of the present disclosure, reference may be made to matters described in standard documents published prior to the present disclosure. For example, reference may be made to the following documents.

[0036] For 3GPP LTE, see TS 36.211 (Physical channels and modulation), TS 36.212 (Multiplexing and channel coding), TS 36.213 (Physical layer procedures), TS 36.300 (General description), and TS 36.331 (Radio resource control).

[0037] For 3GPP NR, see 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 (Overall description of NR and New Generation-Radio Access Network (NG-RAN)), and TS 38.331 (Radio Resource Control Protocol Specification).

[0038] Abbreviations for terms that may be used in this disclosure are defined as follows.

[0039] - BM: beam management

[0040] - CQI: Channel Quality Indicator

[0041] - CRI: Channel state information - reference signal resource indicator

[0042] - CSI: Channel State Information

[0043] - CSI-IM: Channel State Information - Interference Measurement

[0044] - CSI-RS: Channel state information - reference signal

[0045] - DMRS: Demodulation Reference Signal

[0046] - FDM: frequency division multiplexing

[0047] - FFT: fast Fourier transform

[0048] - IFDMA: interleaved frequency division multiple access

[0049] - IFFT: inverse fast Fourier transform

[0050] - L1-RSRP: Layer 1 reference signal received power

[0051] - L1-RSRQ: Layer 1 reference signal received quality

[0052] - MAC: Medium Access Control

[0053] - NZP: non-zero power

[0054] - OFDM: orthogonal frequency division multiplexing

[0055] - PDCCH: Physical downlink control channel

[0056] - PDSCH: Physical downlink shared channel

[0057] - PMI: precoding matrix indicator

[0058] - RE: resource element

[0059] - RI: Rank indicator

[0060] - RRC: Radio Resource Control

[0061] - RSSI: Received signal strength indicator

[0062] - Rx: Reception

[0063] - QCL: quasi co-location

[0064] - SINR: signal to interference and noise ratio

[0065] - SSB (or SS / PBCH block): Synchronization signal block (including primary synchronization signal (PSS), secondary synchronization signal (SSS), and physical broadcast channel (PBCH))

[0066] - TDM: Time Division Multiplexing

[0067] - TRP: transmission and reception point

[0068] - TRS: Tracking Reference Signal

[0069] - Tx: transmission

[0070] - UE: user equipment

[0071] - ZP: Zero Power

[0072] System General

[0073] As more and more communication devices demand greater communication capacity, the need for improved mobile broadband communications compared to existing radio access technologies (RATs) is emerging. Furthermore, massive Machine Type Communications (MTC), which connects numerous devices and objects to provide diverse services anytime, anywhere, is also a key issue to be considered in next-generation communications. Furthermore, communication system design that considers reliability and latency-sensitive services / terminals is being discussed. Accordingly, the introduction of next-generation RATs that consider enhanced mobile broadband communication (eMBB), massive MTC (MMTC), and Ultra-Reliable and Low Latency Communication (URLLC) is being discussed. For convenience, these technologies are referred to as NR in this disclosure. NR is an expression representing an example of 5G RAT.

[0074] A new RAT system, including NR, uses OFDM or a similar transmission scheme. The new RAT system may follow OFDM parameters different from those of LTE. Alternatively, the new RAT system may follow the existing LTE / LTE-A numerology but support a larger system bandwidth (e.g., 100 MHz). Alternatively, a single cell may support multiple numerologies. That is, terminals operating under different numerologies can coexist within a single cell.

[0075] A numerology corresponds to a single subcarrier spacing in the frequency domain. Different numerologies can be defined by scaling the reference subcarrier spacing by an integer N.

[0076] Figure 1 illustrates the structure of a wireless communication system to which the present disclosure can be applied.

[0077] Referring to Fig. 1, the NG-RAN consists of gNBs that provide NG-RA (NG-Radio Access) user plane (i.e., new AS (access stratum) sublayer / PDCP (Packet Data Convergence Protocol) / RLC (Radio Link Control) / MAC / PHY) and control plane (RRC) protocol termination for UE. The gNBs are interconnected via Xn interfaces. The gNBs are also connected to the NGC (New Generation Core) via the NG interface. More specifically, the gNBs are connected to the AMF (Access and Mobility Management Function) via the N2 interface and to the UPF (User Plane Function) via the N3 interface.

[0078] FIG. 2 illustrates a frame structure in a wireless communication system to which the present disclosure can be applied.

[0079] NR systems can support multiple numerologies. Numerologies can be defined by subcarrier spacing and cyclic prefix (CP) overhead. Multiple subcarrier spacings can be derived by scaling the base (reference) subcarrier spacing by an integer N (or μ). Furthermore, even if it is assumed that very low subcarrier spacing is not used at very high carrier frequencies, the numerology used can be selected independently of the frequency band. Furthermore, NR systems can support various frame structures corresponding to multiple numerologies.

[0080] Below, we examine OFDM numerologies and frame structures that can be considered in NR systems. The various OFDM numerologies supported in NR systems can be defined as shown in Table 1 below.

[0081] μΔf=2 μ ·15 [kHz]CP015 Normal 130 Normal 260 Normal, Extended 3120 Normal 4240 Normal

[0082] NR supports multiple numerologies (or subcarrier spacings (SCS)) to support various 5G services. For example, an SCS of 15 kHz supports wide areas in traditional cellular bands; an SCS of 30 kHz / 60 kHz supports dense urban areas, lower latency, and wider carrier bandwidth; and an SCS of 60 kHz or higher supports bandwidths greater than 24.25 GHz to overcome phase noise.

[0083] The NR frequency band is defined by two types of frequency ranges (FR1 and FR2). FR1 and FR2 can be configured as shown in Table 2 below. FR2 can also mean millimeter wave (mmW).

[0084] Frequency Range Designation Corresponding Frequency Range Subcarrier Spacing FR1410MHz - 7125MHz 15, 30, 60kHz FR224250MHz - 52600MHz 60, 120, 240kHz

[0085] Regarding the frame structure in the NR system, the sizes of the various fields in the time domain are T c =1 / (Δf max ·N f ) is expressed as a multiple of the time unit. Here, Δf max =480·10 3 Hz and N f =4096. Downlink and uplink transmissions are T f =1 / (Δf max N f / 100)·T c = It is organized into radio frames with a duration of 10ms. Here, each radio frame is T sf =(Δf max N f / 1000)·T c =1ms It consists of 10 subframes with an interval of . In this case, there may be one set of frames for uplink and one set of frames for downlink. In addition, transmission in uplink frame number i from a terminal is T earlier than the start of the corresponding downlink frame from the terminal.TA =(N TA +N TA,offset )T c It should start before. For the subcarrier spacing configuration μ, slots are n within a subframe. s μ ∈{0,..., N slot subframe,μ-1} are numbered in increasing order, and n within a radio frame. s,f μ ∈{0,..., N slot frame,μ -1} are numbered in increasing order. One slot is N symb slot It consists of consecutive OFDM symbols, and N symb slot is determined by CP. Slot n in subframe s μ The start of OFDM symbol n in the same subframe s μ N symb slot are aligned temporally with the start of the OFDM signal. Not all terminals can transmit and receive simultaneously, which means that not all OFDM symbols in a downlink slot or uplink slot can be utilized.

[0086] Table 3 shows the number of OFDM symbols per slot in a general CP (N symb slot ), the number of slots per wireless frame (N slot frame,μ ), number of slots per subframe (N slot subframe,μ), and Table 4 shows the number of OFDM symbols per slot in the extended CP, the number of slots per radio frame, and the number of slots per subframe.

[0087] μN symb slot N slot frame,μ N slotsubframe,μ01410111420221440431480841416016

[0088] μN symb slot N slot frame,μ N slot subframe,μ212404

[0089] FIG. 2 is an example when μ=2 (SCS is 60 kHz), and referring to Table 3, 1 subframe can include 4 slots. 1 subframe={1,2,4} slot illustrated in FIG. 2 is an example, and the number of slot(s) that can be included in 1 subframe is defined as in Table 3 or Table 4. In addition, a mini-slot can include 2, 4, or 7 symbols, or more or fewer symbols.

[0090] Regarding physical resources in an NR system, antenna ports, resource grids, resource elements, resource blocks, carrier parts, etc. can be considered. Below, the physical resources that can be considered in an NR system will be examined in detail.

[0091] First, with respect to antenna ports, antenna ports are defined such that the channel through which a symbol on an antenna port is carried can be inferred from the channel through which another symbol on the same antenna port is carried. Two antenna ports are said to be in a QC / QCL (quasi co-located or quasi co-location) relationship if the large-scale properties of the channel through which a symbol on one antenna port is carried can be inferred from the channel through which a symbol on another antenna port is carried. Here, the large-scale properties include one or more of delay spread, Doppler spread, frequency shift, average received power, and received timing.

[0092] FIG. 3 illustrates a resource grid in a wireless communication system to which the present disclosure can be applied.

[0093] Referring to Figure 3, the resource grid is N in the frequency domain. RB μ N sc RB It consists of subcarriers, and one subframe is 14·2 μ It is described as an example, but not limited to, that it consists of OFDM symbols. In an NR system, the transmitted signal is N RB μ N sc RB One or more resource grids consisting of subcarriers and 2 μ N symb (μ) is described by OFDM symbols. Here, N RB μ≤ N RB max,μ is. The above N RB max,μrepresents the maximum transmission bandwidth, which may vary between uplink and downlink as well as between numerologies. In this case, one resource grid may be configured for μ and each antenna port p. Each element of the resource grid for μ and each antenna port p is referred to as 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 indicates the position of the symbol within the subframe. When referring to 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 is a complex value a k,l' (p,μ) . If there is no risk of confusion or if a particular antenna port or numerology is not specified, the indices p and μ can be dropped, resulting in a complex value of a k,l' (p) or a k,l' This can be. Also, a resource block (RB) is N in the frequency domain. sc RB =12 is defined as consecutive subcarriers.

[0094] Point A serves as a common reference point of 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 the SS / PBCH block used by the UE for initial cell selection. It is expressed in resource block units assuming 15 kHz subcarrier spacing for FR1 and 60 kHz subcarrier spacing for FR2.

[0096] - absoluteFrequencyPointA represents the frequency-position of point A expressed as ARFCN (absolute radio-frequency channel number).

[0097] Common resource blocks (CRBs) are numbered from 0 upwards in the frequency domain for a subcarrier spacing setting μ. The center of subcarrier 0 of CRB 0 for a subcarrier spacing setting μ coincides with 'point A'. CRB number n in the frequency domain CRB μ The relationship between the resource elements (k,l) and the subcarrier spacing setting μ is given by the following mathematical expression 1.

[0098]

[0099] In Equation 1, k is defined relative to point A such that k = 0 corresponds to the subcarrier centered at point A. Physical resource blocks are numbered from 0 to N within the bandwidth part (BWP). BWP,i size,μ - Numbered from -1, where i is the number of the BWP. Physical resource block n in BWP i PRB and common resource block n CRB The relationship between them is given by the mathematical formula 2 below.

[0100]

[0101] N BWP,i start,μ is a common resource block where BWP starts relative to common resource block 0.

[0102] FIG. 4 illustrates a physical resource block in a wireless communication system to which the present disclosure can be applied. FIG. 5 illustrates a slot structure in a wireless communication system to which the present disclosure can be applied.

[0103] Referring to FIGS. 4 and 5, a slot includes multiple symbols in the time domain. For example, in the case of a normal CP, one slot includes seven symbols, but in the case of an extended CP, one slot includes six symbols.

[0104] A carrier comprises 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 can correspond to a single numerology (e.g., SCS, CP length, etc.). A carrier can comprise up to N (e.g., 5) BWPs. Data communication is performed through activated BWPs, and only one BWP can be activated for a single terminal. Each element in the resource grid is referred to as a Resource Element (RE), to which one complex symbol can be mapped.

[0105] The NR system can support up to 400 MHz per component carrier (CC). If a terminal operating in such a wideband CC always operates with the radio frequency (RF) chip for the entire CC turned on, the terminal battery consumption may increase. Alternatively, when considering multiple use cases operating within a single wideband CC (e.g., eMBB, URLLC, Mmtc, V2X, etc.), different numerologies (e.g., subcarrier spacing, etc.) may be supported for each frequency band within the CC. Alternatively, each terminal may have different maximum bandwidth capabilities. Considering this, the base station can instruct the terminal to operate only on a portion of the bandwidth rather than the entire bandwidth of the wideband CC, and this portion of bandwidth is conveniently defined as the bandwidth part (BWP). A BWP can be composed of consecutive RBs on the frequency axis and can correspond to a single numerology (e.g., subcarrier spacing, CP length, slot / mini-slot interval).

[0106] Meanwhile, the base station can configure multiple BWPs even within a single CC configured for a terminal. For example, in the PDCCH monitoring slot, a BWP occupying a relatively small frequency range can be configured, and the PDSCH indicated by the PDCCH can be scheduled on a larger BWP. Alternatively, if UEs are concentrated on a specific BWP, some terminals can be configured to a different BWP for load balancing. Alternatively, considering frequency domain inter-cell interference cancellation between neighboring cells, a portion of the spectrum in the middle of the entire bandwidth can be excluded and both BWPs can be configured within the same slot. In other words, the base station can configure at least one DL / UL BWP for a terminal associated with a wideband CC. The base station can activate at least one DL / UL BWP(s) among the configured DL / UL BWP(s) at a specific time (via L1 signaling, MAC CE (Control Element), RRC signaling, etc.). Additionally, the base station can instruct switching to another configured DL / UL BWP (e.g., via L1 signaling or MAC CE or RRC signaling). Alternatively, switching to a configured DL / UL BWP can be performed based on a timer when the timer value expires. In this case, the activated DL / UL BWP is defined as the active DL / UL BWP. However, in situations such as when the terminal is performing the initial access process or before the RRC connection is set up, the configuration for the DL / UL BWP may not be received. Therefore, in these situations, the DL / UL BWP assumed by the terminal is defined as the initially active DL / UL BWP.

[0107] FIG. 6 illustrates 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 same.

[0108] In wireless communication systems, terminals receive information from a base station via the downlink and transmit it to the base station via the uplink. The information transmitted and received between the base station and terminals includes data and various control information, and various physical channels exist depending on the type and purpose of the information being transmitted and received.

[0109] When a terminal is powered on or enters a new cell, it performs an initial cell search operation, such as synchronizing with the base station (S601). To this end, the terminal receives a primary synchronization signal (PSS) and a secondary synchronization signal (SSS) from the base station to synchronize with the base station and obtain information such as a cell identifier (ID). Afterwards, the terminal can receive a physical broadcast channel (PBCH) from the base station to obtain broadcast information within the cell. Meanwhile, the terminal can receive a downlink reference signal (DL RS) during the initial cell search phase to check the downlink channel status.

[0110] A terminal that has completed initial cell search can obtain more specific system information by receiving a physical downlink control channel (PDCCH) and a physical downlink shared channel (PDSCH) according to information included in the PDCCH (S602).

[0111] Meanwhile, when accessing a base station for the first time or when there are no radio resources for signal transmission, the terminal may perform a random access procedure (RACH) for the base station (steps S603 to S606). To this end, the terminal may transmit a specific sequence as a preamble via the Physical Random Access Channel (PRACH) (steps S603 and S605) and receive a response message to the preamble via the Physical Data Channel Control Channel (PDCCH) and the corresponding PDSCH (steps S604 and S606). In the case of a contention-based RACH, a contention resolution procedure (Contention Resolution Procedure) may additionally be performed.

[0112] The terminal that has performed the procedure described above can then perform PDCCH / PDSCH reception (S607) and physical uplink shared channel (PUSCH) / physical uplink control channel (PUCCH) transmission (S608) as general uplink / downlink signal transmission procedures. In particular, the terminal receives downlink control information (DCI) through the PDCCH. Here, DCI includes control information such as resource allocation information for the terminal, and its format varies depending on the purpose of use.

[0113] Meanwhile, the control information that the terminal transmits to the base station via the uplink or that the terminal receives from the base station includes downlink / uplink ACK / NACK (Acknowledgement / Non-Acknowledgement) signals, CQI (Channel Quality Indicator), PMI (Precoding Matrix Indicator), RI (Rank Indicator), etc. In the case of the 3GPP LTE system, the terminal can transmit the above-described control information such as CQI / PMI / RI via PUSCH and / or PUCCH.

[0114] Table 5 shows an example of the DCI format in the NR system.

[0115] DCI Format Utilization 0_0 Scheduling of PUSCH within a cell 0_1 Scheduling of one or multiple PUSCH within a cell, or indicating cell group (CG: cell group) downlink feedback information to the UE 0_2 Scheduling of PUSCH within a cell 1_0 Scheduling of PDSCH within a DL cell 1_1 Scheduling of PDSCH within a cell 1_2 Scheduling of PDSCH within a cell

[0116] Referring to Table 5, DCI formats 0_0, 0_1, and 0_2 may include resource information related to scheduling of PUSCH (e.g., UL / SUL (Supplementary UL), frequency resource allocation, time resource allocation, frequency hopping, etc.), transport block (TB) related information (e.g., MCS (Modulation Coding and Scheme), NDI (New Data Indicator), RV (Redundancy Version), etc.), HARQ (Hybrid - Automatic Repeat and request) related information (e.g., process number, DAI (Downlink Assignment Index), PDSCH-HARQ feedback timing, etc.), multi-antenna related information (e.g., DMRS sequence initialization information, antenna port, CSI request, etc.), power control information (e.g., PUSCH power control, etc.), and the control information included in each DCI format may be predefined.

[0117] DCI format 0_0 is used for scheduling PUSCH in a cell. The information contained in DCI format 0_0 is transmitted after being scrambled with a CRC (cyclic redundancy check) by a C-RNTI (Cell RNTI: Cell Radio Network Temporary Identifier), a CS-RNTI (Configured Scheduling RNTI), or a MCS-C-RNTI (Modulation Coding Scheme Cell RNTI).

[0118] DCI format 0_1 ​​is used to indicate scheduling of one or more PUSCHs in a single cell, or configure grant (CG: configure grant) downlink feedback information to the UE. The information contained in DCI format 0_1 ​​is CRC-scrambled and transmitted using the C-RNTI, CS-RNTI, SP-CSI-RNTI (Semi-Persistent CSI RNTI), or MCS-C-RNTI.

[0119] DCI format 0_2 is used for scheduling PUSCH in a cell. The information contained in DCI format 0_2 is CRC-scrambled and transmitted using C-RNTI, CS-RNTI, SP-CSI-RNTI, or MCS-C-RNTI.

[0120] Next, DCI formats 1_0, 1_1, and 1_2 may include resource information related to scheduling of PDSCH (e.g., frequency resource allocation, time resource allocation, virtual resource block (VRB)-physical resource block (PRB) mapping, etc.), transport block (TB) related information (e.g., MCS, NDI, RV, etc.), HARQ related information (e.g., process number, DAI, PDSCH-HARQ feedback timing, etc.), multi-antenna related information (e.g., antenna port, transmission configuration indicator (TCI), sounding reference signal (SRS) request, etc.), PUCCH related information (e.g., PUCCH power control, PUCCH resource indicator, etc.), and control information included in each DCI format may be predefined.

[0121] DCI format 1_0 is used for scheduling PDSCH in a DL cell. The information contained in DCI format 1_0 is CRC-scrambled and transmitted using C-RNTI, CS-RNTI, or MCS-C-RNTI.

[0122] DCI format 1_1 is used for scheduling PDSCH in a single cell. The information contained in DCI format 1_1 is CRC-scrambled and transmitted using C-RNTI, CS-RNTI, or MCS-C-RNTI.

[0123] DCI format 1_2 is used for scheduling PDSCH in a single cell. The information contained in DCI format 1_2 is CRC-scrambled and transmitted using C-RNTI, CS-RNTI, or MCS-C-RNTI.

[0124] Quasi-Co Location (QCL)

[0125] Antenna ports are defined such that the channel through which a symbol on an antenna port is carried can be inferred from the channel through which another symbol on the same antenna port is carried. Two antenna ports are said to be in a QC / QCL (quasi co-located or quasi co-location) relationship if the properties of the channel through which a symbol on one antenna port is carried can be inferred from the channel through which a symbol on another antenna port is carried.

[0126] Here, the channel characteristics include one or more of delay spread, Doppler spread, frequency / Doppler shift, average received power, received timing / average delay, and spatial Rx parameter. Here, the spatial Rx parameter refers to a spatial (reception) channel characteristic parameter such as angle of arrival.

[0127] A terminal may be configured with a list of up to M TCI-State settings in the upper layer parameter PDSCH-Config to decode PDSCHs based on detected PDCCHs having DCI intended for the terminal and a given serving cell. M depends on the UE capability.

[0128] Each TCI-State contains parameters for establishing a quasi co-location relationship between one or two DL reference signals and the DM-RS port of the PDSCH.

[0129] The quasi-colocation relationship is established by the upper-layer parameters qcl-Type1 for the first DL RS and qcl-Type2 (if set) for the second DL RS. For two DL RSs, the QCL types are not the same, regardless of whether the references are the same DL RS or different DL RSs.

[0130] The quasi co-location type corresponding to each DL RS is given by the higher layer parameter qcl-Type of QCL-Info, and can take one of the following values:

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

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

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

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

[0135] For example, if a target antenna port is a specific NZP CSI-RS, the corresponding NZP CSI-RS antenna port(s) can be instructed / configured to be QCL with a specific TRS from a QCL-Type A perspective and with a specific SSB from a QCL-Type D perspective. A terminal that has received such an instruction / configuration can receive the corresponding NZP CSI-RS using the Doppler and delay values ​​measured at the QCL-TypeA TRS, and apply the reception beam used for QCL-TypeD SSB reception to the corresponding NZP CSI-RS reception.

[0136] The UE can receive an activation command by MAC CE signaling, which is used to map up to eight TCI states to codepoints in the DCI field 'Transmission Configuration Indication'.

[0137] Multi-TRP related actions

[0138] Coordinated Multi-Point (CoMP) is a technique that effectively controls interference by having multiple base stations exchange (e.g., using the X2 interface) or utilize channel information (e.g., RI / CQI / PMI / LI (layer indicator)) fed back from terminals and cooperatively transmit it to terminals. Depending on the method used, CoMP can be categorized into joint transmission (JT), coordinated scheduling (CS), coordinated beamforming (CB), dynamic point selection (DPS), and dynamic point blocking (DPB).

[0139] The M-TRP transmission method, in which M TRPs transmit data to one terminal, can be broadly divided into i) eMBB M-TRP transmission, a method for increasing transmission rate, and ii) URLLC M-TRP transmission, a method for increasing reception success rate and reducing latency.

[0140] In addition, from the perspective of DCI transmission, M-TRP transmission methods can be divided into i) M-TRP transmission based on M-DCI (multiple DCI) in which each TRP transmits a different DCI, and ii) M-TRP transmission based on S-DCI (single DCI) in which one TRP transmits a DCI. For example, in the case of S-DCI-based M-TRP transmission, all scheduling information for data transmitted by an M TRP must be delivered to the terminal through a single DCI, so it can be used in an ideal backhaul (ideal BH: ideal BackHaul) environment in which dynamic cooperation between the two TRPs is possible.

[0141] The UE may recognize the PUSCH (or PUCCH) scheduled by the DCI received in different control resource sets (CORESETs) (or CORESETs belonging to different CORESET groups) as a PUSCH (or PUCCH) transmitted in different TRPs, or as a PDSCH (or PDCCH) of different TRPs. In addition, the method for UL transmission (e.g., PUSCH / PUCCH) transmitted in different TRPs, described below, can be equally applied to UL transmission (e.g., PUSCH / PUCCH) transmitted in different panels belonging to the same TRP.

[0142] Hereinafter, the CORESET group identifier (group ID) described / mentioned in the present disclosure may mean an index / identification information (e.g., ID) for distinguishing a CORESET for each TRP / panel. And the CORESET group may be a group / union of CORESETs distinguished by an index / identification information (e.g., ID) / the CORESET group ID for distinguishing a CORESET for each TRP / panel. For example, the CORESET group ID may be specific index information defined in the CORSET configuration. In this case, the CORESET group may be set / indicated / defined by an index defined in the CORESET configuration for each CORESET. And / or the CORESET group ID may mean an index / identification information / indicator for distinguishing / identifying between CORESETs set / associated with each TRP / panel. Hereinafter, the CORESET group ID described / mentioned in the present disclosure may be expressed by being replaced with a specific index / specific identification information / specific indicator for distinguishing / identifying the CORESETs set / associated in each TRP / panel. The CORESET group ID, i.e., the specific index / specific identification information / specific indicator for distinguishing / identifying the CORESETs set / associated in each TRP / panel, may be set / instructed to the terminal through higher layer signaling (e.g., RRC signaling) / second layer signaling (L2 signaling, e.g., MAC-CE) / first layer signaling (L1 signaling, e.g., DCI). For example, PDCCH detection may be set / instructed to be performed for each TRP / panel (i.e., for each TRP / panel belonging to the same CORESET group) in units of the corresponding CORESET group.And / or, 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) may be separately managed / controlled for each TRP / panel in the corresponding CORESET group (i.e., for each TRP / panel belonging to the same CORESET group). And / or, HARQ A / N (process / retransmission) for PDSCH / PUSCH, etc. scheduled for each TRP / panel in the corresponding CORESET group (i.e., for each TRP / panel belonging to the same CORESET group) may be managed.

[0143] For example, the ControlResourceSet information element (IE), which is an upper layer parameter, is used to configure a time / frequency control resource set (CORESET). For example, the control resource set (CORESET) may be related to detection and reception of downlink control information. The ControlResourceSet IE may include a CORESET-related ID (e.g., controlResourceSetID) / an index of a CORESET pool for the CORESET (e.g., CORESETPoolIndex) / time / frequency resource configuration of the CORESET / TCI information related to the CORESET, etc. For example, the index of the CORESET pool (e.g., CORESETPoolIndex) may be set to 0 or 1. In the above description, a CORESET group may correspond to a CORESET pool, and a CORESET group ID may correspond to a CORESET pool index (e.g., CORESETPoolIndex).

[0144] Below, we will look at methods for improving reliability in Multi-TRP.

[0145] The following two methods can be considered as transmission and reception methods to improve reliability by using transmission in multiple TRPs.

[0146] FIG. 7 illustrates a multi-TRP transmission method in a wireless communication system to which the present disclosure can be applied.

[0147] Referring to Fig. 7(a), it shows a case where a layer group transmitting the same codeword (CW) / transport block (TB) corresponds to different TRPs. In this case, the layer group may refer to a predetermined layer set consisting of one or more layers. In this case, the amount of transmission resources increases due to the large number of layers, which has the advantage of enabling the use of robust channel coding with a low code rate for TB. In addition, since the channels are different from multiple TRPs, the reliability of the received signal can be expected to be improved based on the diversity gain.

[0148] Referring to Fig. 7(b), an example of transmitting different CWs through layer groups corresponding to different TRPs is shown. At this time, it can be assumed that the TBs corresponding to CW #1 and CW #2 in the figure are the same. That is, CW #1 and CW #2 mean that the same TB is converted into different CWs through channel coding, etc. by different TRPs, respectively. Therefore, it can be viewed as an example of repeated transmission of the same TB. In the case of Fig. 7(b), compared to Fig. 7(a), there may be a disadvantage in that the code rate corresponding to the TB is high. However, it has an advantage in that the code rate can be adjusted or the modulation order of each CW can be adjusted by indicating different RV (redundancy version) values ​​for encoded bits generated from the same TB depending on the channel environment.

[0149] According to the method exemplified in Figures 7(a) and 7(b), the same TB is repeatedly transmitted through different layer groups, and since each layer group is transmitted by a different TRP / panel, the data reception probability of the terminal can be increased. This is referred to as an SDM (Spatial Division Multiplexing)-based M-TRP URLLC transmission method. Layers belonging to different layer groups are transmitted through DMRS ports belonging to different DMRS CDM groups.

[0150] In addition, although the above-described multiple TRP related content was explained based on the SDM (spatial division multiplexing) method using different layers, it can be extended and applied to the FDM (frequency division multiplexing) method based on different frequency domain resources (e.g., RB / PRB (set) etc.) and / or the TDM (time division multiplexing) method based on different time domain resources (e.g., slots, symbols, sub-symbols etc.).

[0151] Multi-TRP, scheduled by at least one DCI, can be performed as follows:

[0152] i) Technique 1 (SDM): n (where n is a natural number) TCI states within a single slot in overlapping time and frequency resource allocation.

[0153] - Technique 1a: Each transmission occasion is a layer or set of layers of the same TB, and each layer or set of layers is associated with a TCI and a set of DMRS port(s). A single codeword with a single redundancy version (RV) is used for all layers or layer sets. From the UE perspective, different coded bits are mapped to different layers or layer sets according to specific mapping rules.

[0154] - Technique 1b: Each transmission occasion is a layer or set of layers of the same TB, and each layer or set of layers is associated with a TCI and a set of DMRS port(s). A single codeword with a single RV is used for each spatial layer or set of layers. The RVs corresponding to each spatial layer or set of layers may be the same or different.

[0155] - Technique 1c: Each transmission occasion is one layer of the same TB with one DMRS port associated with multiple TCI state indices, or one layer of the same TB with multiple DMRS ports associated with multiple TCI indices one by one.

[0156] In the above-described techniques 1a and 1c, the same MCS is applied to all layers or layer sets.

[0157] ii) Technique 2 (FDM): n TCI states (where n is a natural integer) within a single slot in non-overlapping frequency resource allocation. Each non-overlapping frequency resource allocation is associated with one TCI state. The same single / multiple DMRS ports are associated with all non-overlapping frequency resource allocations.

[0158] - Technique 2a: A single codeword with a single RV is used across the entire resource allocation. From the UE perspective, a common RB mapping (layer mapping of codewords) is applied across all resource allocations.

[0159] - Technique 2b: A single codeword with a single RV is used for each non-overlapping frequency resource allocation. The RVs corresponding to each non-overlapping frequency resource allocation may be identical or different.

[0160] In technique 2a, the same MCS is applied to all non-overlapping frequency resource allocations.

[0161] iii) Technique 3 (TDM): n TCI states (where n is a natural integer) within a single slot in non-overlapping time resource allocation. Each transmission occasion in a TB has one TCI and one RV with a time granularity of a mini-slot. All transmission occasion(s) within a slot use a common MCS with the same single or multiple DMRS port(s). The RV / TCI states can be the same or different across transmission occasions.

[0162] iv) Technique 4 (TDM): n (n is a natural number) TCI states within K (n<=K, K is a natural number) different slots. Each transmission occasion in a TB has one TCI and one RV. All transmission occasion(s) across K slots use a common MCS with the same single or multiple DMRS port(s). The RV / TCI states can be the same or different across transmission occasions.

[0163] Hereinafter, DL MTRP-URLLC in the present disclosure means that the same data (e.g., transport block (TB) / DCI) is transmitted by M-TRP using different layer / time / frequency resources. For example, TRP 1 transmits the same data / DCI in resource 1, and TRP 2 transmits the same data / DCI in resource 2. A UE configured with the DL MTRP-URLLC transmission method receives the same data / DCI using different layer / time / frequency resources. Here, the UE is instructed by the base station which QCL RS / type (i.e., DL TCI state) to use in the layer / time / frequency resource 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 are instructed. Since the UE receives the same data / DCI through resource 1 and resource 2, high Reliability can be achieved. This DL MTRP URLLC can be applied to PDSCH / PDCCH.

[0164] Conversely, UL MTRP-URLLC means that the same data / UCI is received from a UE by MTRPs using different layer / time / frequency resources. For example, TRP 1 receives the same data / UCI from the UE on resource 1, and TRP 2 receives the same data / UCI from the UE on resource 2, and then shares the received data / UCI through the connected backhaul link between the TRPs. A UE configured with the UL MTRP-URLLC transmission method transmits the same data / UCI using different layer / time / frequency resources. Here, the UE is instructed by the base station which Tx beam and which Tx power (i.e., UL TCI state) to use in the layer / time / frequency resources transmitting the same data / UCI. For example, if the same data / UCI is transmitted on resource 1 and resource 2, the UL TCI state used on resource 1 and the UL TCI state used on resource 2 are instructed. This UL MTRP URLLC can be applied to PUSCH / PUCCH.

[0165] In addition, in the methods proposed in this document, using (mapping) a specific TCI state (or TCI) when receiving data / DCI / UCI for a certain frequency / time / spatial resource can mean that, in the case of DL, a channel is estimated from DMRS using the QCL type and QCL RS indicated by the corresponding TCI state in the frequency / time / spatial resource, and data / DCI is received / demodulated with the estimated channel. In the case of UL, it can mean that DMRS and data / UCI are transmitted / modulated using the Tx beam and / or Tx power indicated by the corresponding TCI state in the frequency / time / spatial resource.

[0166] The above UL TCI state contains Tx beam and / or Tx power information of the UE, and may be set to the UE through other parameters such as spatial relation info instead of the TCI state. The UL TCI state may be directly indicated in the UL grant DCI, or may mean spatial relation info of an SRS resource indicated through the SRS resource indicator (SRI) field of the UL grant DCI. Or, it may mean an open loop (OL) Tx power control parameter (j: index for open loop parameters Po and alpha (up to 32 parameter value sets per cell) linked to the value indicated through the SRI field of the UL grant DCI, q_d: index of DL RS for path loss (PL) measurement (up to 3 measurements per cell), l: closed loop power control process index (up to 2 processes per cell)).

[0167] On the other hand, MTRP-eMBB means that M-TRP transmits different data using different layer / time / frequency, and a UE configured with the MTRP-eMBB transmission method is instructed to multiple TCI states by DCI, and it is assumed that the data received using the QCL RS of each TCI state is different data.

[0168] In addition, the UE can determine whether it is MTRP URLLC transmission / reception or MTRP eMBB transmission / reception by using the RNTI for MTRP-URLLC and the RNTI for MTRP-eMBB separately. That is, if the RNTI for URLLC is used to mask the CRC of the DCI, it is identified as URLLC transmission, and if the RNTI for eMBB is used to mask the CRC of the DCI, it is identified as eMBB transmission. Alternatively, the base station can configure MTRP URLLC transmission / reception or MTRP eMBB transmission / reception to the UE through other new signaling.

[0169] For convenience of explanation, the present disclosure applies the proposed method assuming cooperative transmission / reception between two TRPs. However, it can be expanded to a multi-TRP environment of three or more, and also to a multi-panel environment. Different TRPs can be recognized by the UE as different Transmission Configuration Indication (TCI) states. That is, when the UE receives / transmits data / DCI / UCI using TCI state 1, it means that the UE has received / transmitted data / DCI / UCI from / to TRP 1.

[0170] The proposals of the present disclosure can be utilized in situations where MTRP performs cooperative transmission of PDCCH (repeatedly transmitting or dividing the same PDCCH), and some of the proposals can also be utilized in situations where MTRP performs cooperative transmission of PDSCH or cooperative reception of PUSCH / PUCCH.

[0171] In addition, in the present disclosure below, the meaning that multiple base stations (i.e., MTRP) repeatedly transmit the same PDCCH may mean that the same DCI was transmitted through multiple PDCCH candidates, and is the same as the meaning that multiple base stations repeatedly transmit the same DCI. The same DCI may mean two DCIs having the same DCI format / size / payload. Alternatively, even if the payloads of the two DCIs are different, if the scheduling results are the same, they can be referred to as the same DCI. For example, the slot / symbol position of data and the slot / symbol position of ACK (acknowledgement) / NACK (non-acknowledgement) are relatively determined based on the reception time of the DCI by the TDRA (time domain resource allocation) field of the DCI. Here, if the DCI received at time n and the DCI received at time n+1 inform the UE of the same scheduling result, the TDRA fields of the two DCIs will be different, and as a result, the DCI payloads will inevitably be different. The number of repetitions R can be directly indicated by the base station to the UE or can be mutually agreed upon. Alternatively, even if the payloads of two DCIs are different and the scheduling results are not identical, if the scheduling result of one DCI is a subset of the scheduling result of the other DCI, they can be considered the same DCI. For example, if the same data is TDMed and repeatedly transmitted N times, DCI 1 received before the first data indicates data repetition N times, and DCI 2 received after the first data and before the second data indicates data repetition N-1 times. The scheduling data of DCI 2 becomes a subset of the scheduling data of DCI 1, and since both DCIs schedule the same data, they can also be considered the same DCI in this case.

[0172] In addition, in the present disclosure below, multiple base stations (i.e., MTRPs) dividing and transmitting the same PDCCH means that one DCI is transmitted through one PDCCH candidate, but some resources for which the PDCCH candidate is defined are transmitted by TRP 1 and the remaining resources are transmitted by TRP 2. For example, when TRP 1 and TRP 2 divide and transmit a PDCCH candidate corresponding to an aggregation level m1+m2, the PDCCH candidate is divided into PDCCH candidate 1 corresponding to an aggregation level m1 and PDCCH candidate 2 corresponding to an aggregation level m2, and TRP 1 transmits PDCCH candidate 1 and TRP 2 transmits PDCCH candidate 2 using different time / frequency resources. After receiving PDCCH candidate 1 and PDCCH candidate 2, the UE generates a PDCCH candidate corresponding to an aggregation level m1+m2 and attempts to decode the DCI.

[0173] There are two possible implementations when the same DCI is transmitted across multiple PDCCH candidates.

[0174] First, the DCI payload (control information bits + CRC) can be encoded through a single channel encoder (e.g., a polar encoder), and the resulting coded bits can be divided and transmitted by two TRPs. In this case, the coded bits transmitted by each TRP can encode the entire DCI payload or only a portion of the DCI payload. Second, the DCI payload (control information bits + CRC) can be divided into two (DCI 1 and DCI 2), and each can be encoded through a channel encoder (e.g., a polar encoder). Afterwards, the two TRPs can transmit the coded bits corresponding to DCI 1 and the coded bits corresponding to DCI 2, respectively.

[0175] In summary, it can be said that multiple base stations (i.e., MTRPs) divide / repeat the same PDCCH and transmit it over multiple monitoring occasions (MOs).

[0176] i) It may mean that coded DCI bits encoding the entire DCI contents of the corresponding PDCCH are repeatedly transmitted through each MO for each base station (i.e., STRP); or,

[0177] ii) It may mean that the coded DCI bits that encode the entire DCI contents of the corresponding PDCCH are divided into multiple parts, and different parts are transmitted for each base station (i.e., STRP) through each MO; or,

[0178] iii) It may mean that the DCI contents of the corresponding PDCCH are divided into multiple parts, and different parts are individually encoded for each base station (i.e., STRP) and transmitted through each MO.

[0179] That is, regardless of whether the PDCCH is repeatedly transmitted or split, it can be understood that the PDCCH is transmitted multiple times across multiple transmission occasions (TOs). Here, TO refers to a specific time / frequency resource unit in which the PDCCH is transmitted. For example, if the PDCCH is transmitted multiple times across slots 1, 2, 3, and 4 (in a specific resource block (RB)), TO can refer to each slot. If the PDCCH is transmitted multiple times across RB sets 1, 2, 3, and 4 (in a specific slot), TO can refer to each RB set. Or, if the PDCCH is transmitted multiple times across different times and frequencies, TO can refer to each time / frequency resource. In addition, the TCI state used for DMRS channel estimation can be set differently for each TO, and it can be assumed that TOs with different TCI states are transmitted by different TRPs / panels. When multiple base stations transmit a PDCCH repeatedly or in segments, it means that the PDCCH is transmitted across multiple TOs, and the union of the TCI states set for the TOs consists of two or more TCI states. For example, if a PDCCH is transmitted across TOs 1, 2, 3, and 4, TCI states 1, 2, 3, and 4 may be set for TOs 1, 2, 3, and 4 respectively, which means that TRP i cooperatively transmitted the PDCCH on TO i.

[0180] For multiple TOs instructed to the UE for repeated or divided transmission of PDCCH / PDSCH / PUSCH / PUCCH, each TO is UL transmitted toward a specific TRP or DL ​​received from a specific TRP. Here, a UL TO (or TO of TRP 1) transmitted toward TRP 1 means a TO that uses the first value of two spatial relations, two UL TCIs, two UL power control parameters, and / or two pathloss reference signals (PLRS) instructed to the UE, and a UL TO (or TO of TRP 2) transmitted toward TRP 2 means a TO that uses the second value of two spatial relations, two UL TCIs, two UL power control parameters, and / or two PLRSs instructed to the UE. Similarly, in DL transmission, the DL TO (or TO of TRP 1) transmitted by TRP 1 means the TO that uses the first value among the two DL TCI states indicated to the UE (for example, when two TCI states are set in CORESET), and the DL TO (or TO of TRP 2) transmitted by TRP 2 means the TO that uses the second value among the two DL TCI states indicated to the UE (for example, when two TCI states are set in CORESET).

[0181] The proposal of the present disclosure can be extended to various channels such as PUSCH / PUCCH / PDSCH / PDCCH.

[0182] The proposal of the present disclosure is applicable to both cases of repeatedly transmitting the channel on different time / frequency / space resources and cases of divided transmission.

[0183] Data transmission and HARQ (Hybrid Automatic Repeat and reQuest)-ACK (Acknowledgement) process

[0184] FIG. 8 illustrates a HARQ-ACK process for downlink data in a wireless communication system to which the present disclosure can be applied.

[0185] Referring to FIG. 8, the terminal can detect a PDCCH in slot #n. Here, the PDCCH includes downlink scheduling information (e.g., DCI formats 1_0, 1_1), and the PDCCH indicates a DL assignment-to-PDSCH offset (K0) and a PDSCH-HARQ-ACK reporting offset (K1). For example, DCI formats 1_0, 1_1 can include the following information:

[0186] - Frequency domain resource assignment: Indicates the RB resources (e.g., one or more (non-)contiguous RBs) allocated to the PDSCH.

[0187] - Time domain resource assignment: K0, which indicates the starting position (e.g., OFDM symbol index) and length (e.g., number of OFDM symbols) of the PDSCH within the slot.

[0188] - PDSCH HARQ feedback timing indicator (PDSCH-to-HARQ_feedback timing indicator): Indicates K1

[0189] - HARQ process number (4 bits): Indicates the HARQ process ID (Identity) for data (e.g., PDSCH, TB)

[0190] - PUCCH resource indicator (PRI): Indicates the PUCCH resource to be used for UCI transmission among multiple PUCCH resources within the PUCCH resource set.

[0191] Thereafter, the terminal may receive PDSCH in slot #(n+K0) according to scheduling information of slot #n, and then transmit UCI through PUCCH in slot #(n+K1). Here, the UCI includes a HARQ-ACK response to the PDSCH. If the PDSCH is configured to transmit up to 1 TB, the HARQ-ACK response may be composed of 1 bit. If the PDSCH is configured to transmit up to 2 TB, the HARQ-ACK response may be composed of 2 bits if spatial bundling is not configured, and may be composed of 1 bit if spatial bundling is configured. If the HARQ-ACK transmission timing for multiple PDSCHs is designated as slot #(n+K1), the UCI transmitted in slot #(n+K1) includes HARQ-ACK responses for multiple PDSCHs.

[0192] Multimedia Broadcast / Multicast Service (MBMS)

[0193] MBMS can be divided into i) single frequency network (SFN) method, in which multiple base station cells are synchronized and transmit the same data through PMCH (physical multicast channel), and ii) single cell point to multipoint (SC-PTM) method, in which broadcasting is done within the cell coverage through PDCCH / PDSCH channels. SFN method is used to provide broadcasting service to a wide area (e.g., MBMS area) using semi-statically allocated resources, while SC-PTM method is mainly used to provide broadcasting service only within cell coverage using dynamic resources.

[0194] SC-PTM provides one logical channel, the Single Cell Multicast Control Channel (SC-MCCH), and one or more logical channels, the Single Cell Multicast Traffic Channel (SC-MTCH). These logical channels are mapped to the downlink shared channel (DL-SCH), a transport channel, and the physical channel, the PDSCH. The PDSCH, which transmits SC-MCCH or SC-MTCH data, is scheduled through the PDCCH indicated by the group-RNTI (G-RNTI). At this time, a temporary multicast group ID (TMGI) corresponding to a service identifier (ID: identity) can be mapped one-to-one with a specific G-RNTI value. Therefore, if a base station provides multiple services, multiple G-RNTI values ​​can be assigned for SC-PTM transmission. One or more terminals can perform PDCCH monitoring using a specific G-RNTI to receive a specific service. Here, a DRX on-duration period can be set for SC-PTM only for a specific service / specific G-RNTI. In this case, the terminals wake up only during the specific on-duration period and perform PDCCH monitoring for the G-RNTI.

[0195] Method for performing transmission and reception on a group common downlink channel considering a terminal in inactive mode

[0196] - PUCCH: Physical Uplink Control Channel

[0197] - PUSCH: Physical Uplink Shared Channel

[0198] - MCCH: Multicast Control Channel

[0199] - MTCH: Multicast Traffic Channel

[0200] - RRM: Radio resource management

[0201] - RLM: Radio link monitoring

[0202] - SCS: Sub-carrier spacing

[0203] - RLM: Radio link monitoring

[0204] - DCI: Downlink Control Information

[0205] - CAP: Channel Access Procedure

[0206] - Ucell: Unlicensed cell

[0207] - PCell: Primary Cell

[0208] - PSCell: Primary SCG Cell

[0209] - TBS: Transport Block Size

[0210] - TDRA: Time Domain Resource Allocation

[0211] - SLIV: Starting and Length Indicator Value (This is an indicator value for the starting symbol index and number of symbols in the slot of the PDSCH and / or PUSCH. It can be set as a component of an entry that constitutes the TDRA field in the PDCCH that schedules the corresponding PDSCH and / or PUSCH.)

[0212] - BWP: BandWidth Part (may be composed of consecutive resource blocks (RBs) on the frequency axis. May correspond to a single numerology (e.g., SCS, CP length, slot / mini-slot duration, etc.). In addition, multiple BWPs may be configured in a single carrier (the number of BWPs per carrier may also be limited), but the number of activated BWPs may be limited to a portion (e.g., 1) per carrier.)

[0213] - CORESET: Control Resource Set (COntrol REsourse SET) (Refers to the time-frequency resource area in which PDCCH can be transmitted, and the number of CORESETs per BWP may be limited.)

[0214] - REG: Resource element group

[0215] - SFI: Slot Format Indicator (An indicator indicating the symbol level DL / UL direction within a specific slot(s), transmitted through the group common PDCCH.)

[0216] - COT: Channel occupancy time

[0217] - SPS: Semi-persistent scheduling

[0218] - QCL: Quasi-Co-Location (QCL relationship between two reference signals (RS)) may mean that QCL parameters such as Doppler shift, Doppler spread, average delay, delay spread, and spatial Rx parameter obtained from one RS can be applied to another RS ​​(or antenna port(s) of the RS). In NR systems, four QCL types are defined as follows: 'typeA': {Doppler shift, Doppler spread, average delay, delay spread}, 'typeB': {Doppler shift, Doppler spread}, 'typeC': {Doppler shift, average delay}, 'typeD': {Spatial Rx parameter}. For any DL RS antenna port(s), the first DL RS is set as the reference for QCL type X (X=A, B, C, or D), and additionally The second DL RS can be set as a reference for QCL type Y (Y=A, B, C, or D, but X≠Y).

[0219] - TCI: Transmission Configuration Indication (A TCI state includes the QCL relationship between one or more DL RSs, such as DM-RS ports of a PDSCH, DM-RS ports of a PDCCH, or CSI-RS port(s) of a CSI-RS resource. For the 'Transmission Configuration Indication' field in the DCI that schedules the PDSCH, the TCI state index corresponding to each code point that constitutes the field is activated by the MAC control element (CE), and the TCI state setting for each TCI state index is set through RRC signaling. In the Rel-16 NR system, the TCI state is set between DL RSs, but in future releases, setting between DL RS and UL RS or UL RS and UL RS may be allowed. Examples of UL RSs include SRS, PUSCH DM-RS, PUCCH DM-RS, etc.)

[0220] - SRI: SRS resource indicator (Indicates one of the SRS resource index values ​​set in the 'SRS resource indicator' among the fields in the DCI that schedules the PUSCH. When transmitting a PUSCH, the UE can transmit the PUSCH using the same spatial domain transmission filter used for transmitting and receiving the reference signal linked to the corresponding SRS resource. Here, the reference RS is set by RRC signaling through the SRS spatial relationship information (SRS-SpatialRelationInfo) parameter for each SRS resource, and an SS / PBCH block, CSI-RS, or SRS can be set as the reference RS.)

[0221] - TRP: Transmission and Reception Point

[0222] - PLMN ID: Public Land Mobile Network identifier

[0223] - RACH: Random Access Channel

[0224] - RAR: Random Access Response

[0225] - Msg3: A message transmitted through UL-SCH (uplink shared channel) containing C-RNTI MAC CE or CCCH (common control channel) service data unit (SDU), provided from a higher layer, and associated with the UE Contention Resolution Identity as part of the random access procedure.

[0226] - Special Cell: For dual connectivity operation, the term "Special Cell" refers to the PCell of the master cell group (MCG) or the PSCell of the secondary cell group (SCG), depending on whether the MAC entity is associated with the MCG or SCG, respectively. Otherwise, the term "Special Cell" refers to the PCell. Special Cells support PUCCH transmission and contention-based random access and are always active.

[0227] - Serving Cell: Includes PCell, PSCell, and SCell (secondary cell).

[0228] - CG: Configured Grant

[0229] - Type 1 CG or Type 2 CG: Type 1 configured grant or Type 2 configured grant

[0230] - Fall-back DCI: Indicates the DCI format that can be used for fall-back operation, for example, DCI format 0_0, 1_0.

[0231] - Non-fallback DCI: Indicates a DCI format other than fall-back DCI, for example, DCI format 0_1, 1_1.

[0232] - SS: Search space

[0233] - FDRA: Frequency domain resource allocation

[0234] - TDRA: Time domain resource allocation

[0235] - LP, HP: Low(er) priority, High(er) priority

[0236] - A / N for Cell A: A / N (acknowledgement / negative acknowledgement) information for data (e.g., PDSCH) received from Cell A.

[0237] - UL CI: Uplink cancellation indication

[0238] - CFR: Common frequency resource for MBS (multicast and broadcast service). One DL CFR provides group common PDCCH and group common PDSCH transmission resources for MBS transmission and reception. One UL CFR provides HARQ-ACK PUCCH resources for group common PDSCH reception. One CFR is one MBS-specific BWP or one UE-specific BWP. Alternatively, one or more CFRs can be configured within one UE-specific BWP. One CFR is associated with one UE-specific BWP.

[0239] - TMGI: Temporary Mobile Group Identity. An MBS service identifier that indicates a specific service.

[0240] - G-RNTI: Group Radio Network Temporary Identifier. Indicates the terminal group identifier receiving MBS.

[0241] The contents discussed above (3GPP system, frame structure, NR system, etc.) can be applied in combination with the methods proposed in the present disclosure, which will be described later, or can be supplemented to clarify the technical characteristics of the methods proposed in the present disclosure. In the present disclosure, ' / ' means 'and', 'or', or 'and / or', depending on the context.

[0242] In the prior art, a base station can set a terminal-specific SPS configuration for a specific terminal and allocate downlink SPS transmission resources that are repeated according to the set cycle. Here, the DCI of the terminal-specific PDCCH can indicate the activation of a specific SPS configuration index (SPS activation), thereby allowing the terminal to repeatedly receive the SPS transmission resources according to the set cycle. These SPS transmission resources are used for initial HARQ (hybrid automatic repeat request) transmission, and the base station can also allocate retransmission resources for a specific SPS configuration index (SPS configuration index) through the DCI of the terminal-specific PDCCH. For example, if a terminal reports a HARQ NACK for an SPS transmission resource, the base station can allocate retransmission resources using the DCI so that the terminal can receive the downlink retransmission. Additionally, the DCI of the terminal-only PDCCH can indicate the deactivation of a specific SPS configuration index (SPS release or SPS deactivation), and the terminal receiving this does not receive the indicated SPS transmission resources. Here, the CRC (cyclic redundancy check) of the DCI for activation / retransmission / deactivation of the SPS is scrambled with the CS-RNTI (Configured Scheduling-RNTI).

[0243] Advanced wireless communication systems (e.g., Rel-17 NR systems) seek to introduce DL broadcast or DL ​​multicast transmission methods to support Multicast Broadcast Service (MBS) services similar to the aforementioned MBMS. Base stations provide point-to-multipoint (PTM) transmission methods and / or point-to-point (PTP) transmission methods for DL ​​broadcast or DL ​​multicast transmission.

[0244] In the PTM transmission method for MBS, the base station can set a common frequency resource (CFR). The base station transmits a group common PDCCH (PDCCH) and a group common PDSCH (PDSCH) to multiple terminals through the CFR. Multiple terminals simultaneously receive the same group common PDCCH and PDSCH transmissions and decode the same MBS data.

[0245] On the other hand, in the PTP transmission method for MBS, the base station transmits a terminal-specific PDCCH and a terminal-specific PDSCH to a specific terminal, and only the terminal receives the terminal-specific PDCCH and PDSCH. Here, if there are multiple terminals receiving the same MBS service, the base station separately transmits the same MBS data to each terminal through different terminal-specific PDCCHs and terminal-specific PDSCHs. In other words, the same MBS data is provided to multiple terminals, but different channels (i.e., PDCCH, PDSCH) are used for each terminal.

[0246] As described above, in the PTM transmission method, the base station transmits multiple group common PDSCHs to multiple terminals. Here, the base station can receive HARQ-ACKs for the group common PDSCHs from multiple terminals through terminal-dedicated PUCCH resources.

[0247] Here, if the TB (Transport Block) for the multicast PDSCH (or group common PDSCH) is successfully decoded, the terminal transmits an ACK as HARQ-ACK information. On the other hand, if the TB (Transport Block) is not successfully decoded, the terminal transmits a NACK as HARQ-ACK information. This HARQ-ACK transmission method is referred to as an ACK / NACK-based HARQ-ACK method (mode). Generally, the terminal can transmit an ACK / NACK-based HARQ-ACK using a terminal-dedicated PUCCH resource.

[0248] On the other hand, if a NACK only based HARQ-ACK method (mode) is set for a multicast PDSCH (or group common PDSCH), the terminal does not perform PUCCH transmission in the case of ACK, but performs PUCCH transmission only in the case of NACK. Here, PUCCH is a group common PUCCH resource, and only NACK can be transmitted as HARQ-ACK information.

[0249] In the case of existing wireless communication systems, only RRC connected (RRC_CONNECTED) mode terminals can receive multicast PDCCH / PDSCH, and broadcast PDCCH / PDSCH can be received by terminals regardless of the RRC state.

[0250] In contrast, in next-generation wireless communication systems, RRC inactive (RRC_INACTIVE) mode terminals are also defined / configured to be able to receive multicast PDCCH / PDSCH. In this regard, the base station can transmit the multicast PDCCH / PDSCH by applying beam sweeping according to the SSB beam index (e.g., SSB resource index) so that multiple terminals can receive the multicast PDCCH / PDSCH. In this case, since the base station does not know the SSB beam that a specific terminal will receive, it needs to repeat the multicast PDCCH / PDSCH transmission for all SSB beams. This may waste radio resources. In addition, since the base station does not know the SSB beam that a specific terminal will receive, a problem may occur in which scheduling is performed on a number of channels exceeding the maximum number that a terminal that simultaneously performs SDT (small data transmission) and MBS in RRC inactive mode can receive.

[0251] Considering the problems described above, the present disclosure proposes a method for preventing waste of wireless resources and allowing a base station to know information about an SSB beam received by an RRC-inactive (RRC_INACTIVE) mode terminal in order to receive a channel suitable for the terminal's capability, and a channel reception method suitable for the terminal's capability, through specific examples.

[0252] FIG. 9 illustrates transmission and reception of group common PDCCH / PDSCH and HARQ-ACK applicable to the present disclosure.

[0253] Referring to FIG. 9, a terminal can receive group common PDCCH / PDSCHs scheduled by different G-RNTIs through FDM (frequency division multiplexing) or TDM (time division multiplexing).

[0254] A base station can set a multicast CFR (common frequency resource), which is a frequency domain similar to a BWP. At this time, a terminal can receive a group common PDCCH / PDSCH through the multicast CFR. A terminal receiving a multicast PDCCH / PDSCH can activate one DL BWP to receive a unicast PDCCH / PDSCH, and can receive the group common PDCCH / PDSCH through the CFR associated with the activated DL BWP. At this time, if the terminal is in RRC connected (RRC_CONNECTED) mode, the terminal can transmit a multicast HARQ-ACK for the multicast PDCCH / PDSCH. In contrast, a terminal in RRC idle (RRC_Idle) mode or RRC inactive (RRC_INACTIVE) mode can receive the group common PDCCH through the multicast CFR associated with the initial DL BWP.

[0255] FIG. 10 illustrates an operation method of a terminal according to an embodiment of the present disclosure.

[0256] FIG. 10 illustrates the operation of a terminal based on the proposed method of the present disclosure described below (e.g., one or a combination of Embodiments 1, 2, 3, and detailed embodiments thereof). The examples in FIG. 10 are provided for convenience of explanation and do not limit the scope of the present disclosure. Some of the step(s) illustrated in FIG. 10 may be omitted depending on the circumstances and / or settings. Furthermore, the terminal in FIG. 10 is merely an example and may be implemented as the device illustrated in FIG. 12 below. For example, the processor (102 / 202) of FIG. 12 can control the transceiver (106 / 206) to transmit and receive channels / signals / data / information, etc. (e.g., RRC signaling, MAC CE, DCI for UL / DL scheduling, SRS, PDCCH, PDSCH, PUSCH, PUCCH, etc.), and can also control the processor (102 / 202) to store the transmitted or received channels / signals / data / information, etc. in the memory (104 / 204).

[0257] Referring to FIG. 10, the terminal can perform measurements on multiple spatial parameters to select a specific spatial parameter (step S1010).

[0258] Here, the terminal may be in idle mode or inactive mode based on RRC (radio resource control). In other words, the terminal may be a terminal that is not in RRC connected mode.

[0259] In this regard, the specific spatial parameter may be based on at least one of an index of a synchronization signal block (SSB) resource or an index of a channel state information-reference signal (CSI-RS) resource.

[0260] Thereafter, the terminal can perform uplink transmission based on the specific spatial parameter (step S1020).

[0261] In this regard, the uplink transmission may include at least one of transmission of a preamble for random access or transmission of an uplink data channel.

[0262] For example, if an uplink transmission corresponds to transmission of a preamble, transmission of the preamble may be performed using preamble resources or preamble identification information mapped to specific spatial parameters.

[0263] For another example, if the uplink transmission corresponds to the transmission of an uplink data channel, the transmission of the uplink data channel may be performed using a configured grant-based resource (e.g., a CG PUSCH resource) that is mapped to a specific spatial parameter.

[0264] Through this process, the terminal can obtain information about its preferred spatial parameters (e.g., information about the best beam).

[0265] Thereafter, the terminal can receive multicast-based downlink transmission based on specific spatial parameters (step S1030).

[0266] For example, multicast-based downlink transmission may include multicast PDCCH transmission, multicast PDSCH transmission, etc.

[0267] In this regard, for multicast-based downlink transmission, M (M) including the specific spatial parameter among the total N spatial parameters <N)의 공간 파라미터와 관련된 적어도 하나의 모니터링 기회(monitoring occasion)가 설정될 수 있다. 일 예로, M개의 공간 파라미터는 멀티캐스트 기반의 서비스 타입(service type)에 기초하여 설정될 수 있다.

[0268] As a specific example, at least one monitoring opportunity may be located within a time window or may span multiple time windows. In this case, each time window may be mapped to at least one of a specific (e.g., multicast) common frequency resource (CFR), a group-radio network temporary identifier (G-RNTI), a G-RNTI group, a search space, or a search space group. Furthermore, when at least one monitoring opportunity spans multiple time windows, multicast-based downlink transmissions based on different spatial parameters may be configured in different time windows.

[0269] Additionally, the terminal may receive information from the base station regarding the mapping between multicast-based downlink transmissions and the above-mentioned specific spatial parameters.

[0270] FIG. 11 illustrates an operation method of a base station according to an embodiment of the present disclosure.

[0271] FIG. 11 illustrates the operation of a base station based on the proposed method of the present disclosure described below (e.g., one or a combination of Embodiments 1, 2, 3, and their detailed embodiments). The examples in FIG. 11 are provided for convenience of explanation and do not limit the scope of the present disclosure. Some of the step(s) illustrated in FIG. 11 may be omitted depending on the circumstances and / or settings. Furthermore, the base station in FIG. 11 is merely an example and may be implemented with the device illustrated in FIG. 12 below. For example, the processor (102 / 202) of FIG. 12 can control the transceiver (106 / 206) to transmit and receive channels / signals / data / information, etc. (e.g., RRC signaling, MAC CE, DCI for UL / DL scheduling, SRS, PDCCH, PDSCH, PUSCH, PUCCH, etc.), and can also control the processor (102 / 202) to store the transmitted or received channels / signals / data / information, etc. in the memory (104 / 204).

[0272] Referring to FIG. 11, a base station can receive an uplink transmission based on a specific spatial parameter selected through measurements of multiple spatial parameters (step S1110).

[0273] Here, the terminal may be in idle mode or inactive mode based on RRC (radio resource control). In other words, the terminal may be a terminal that is not in RRC connected mode.

[0274] In this regard, the specific spatial parameter may be based on at least one of an index of a synchronization signal block (SSB) resource or an index of a channel state information-reference signal (CSI-RS) resource.

[0275] Thereafter, the base station can perform multicast-based downlink transmission based on specific spatial parameters (step S1120).

[0276] Specific descriptions of specific spatial parameters, types of uplink transmission, mapping between multicast-based downlink transmission and specific spatial parameters, and setting of monitoring opportunities related to multicast-based downlink transmission are identical to those described with reference to FIG. 10, so redundant descriptions are omitted.

[0277] In relation to the operations of the terminal and base station described in FIGS. 10 and 11, the following describes specific methods for supporting efficient multicast PDCCH / PDSCH reception in a terminal in an inactive mode.

[0278] The following embodiments are described separately and independently for clarity of explanation, but it is also within the scope of the present disclosure that some components of one embodiment may be combined / combined with some components of another embodiment, or applied in place of the corresponding components.

[0279] Example 1

[0280] This embodiment relates to a method for determining PDCCH assignment for RRC inactive (RRC_INACTIVE) mode.

[0281] For example, multicast reception and / or SDT (small data transmission) may be configured for a terminal. In this case, during the RRC inactive mode, the terminal may receive PDCCH(s) for a DCI format CRC-scrambled by at least C-RNTI for SDT, G-RNTI (and G-CS-RNTI) for multicast, and / or G-RNTI for broadcast.

[0282] In this regard, the terminal can receive the PDCCH according to at least one of the following methods.

[0283] For the methods described below, the value of N may be 16 or another value, or may be a fixed / specific / configurable value depending on the RRC state. For example, for RRC connected (RRC_CONNECTED) mode, the value of N may be 16, and for RRC inactive (RRC_INACTIVE) mode, the value of N may be 8.

[0284] (Method 1-1)

[0285] At any time for a scheduled cell, if a C-RNTI is provided to a UE, a UE in RRC connected mode may be expected to have received at most 16 PDCCHs for DCI formats that schedule 16 PDSCH receptions for which the UE has not received any corresponding PDSCH symbols, and that are CRC scrambled with the C-RNTI, the CS-RNTI, the MCS-C-RNTI, the G-RNTI for multicast, or the G-CS-RNTI. Furthermore, in this case, a UE in RRC connected mode may be expected to have received at most 16 PDCCHs for DCI formats that schedule 16 PUSCH receptions for which the UE has not received any corresponding PUSCH symbols, and that are CRC scrambled with the C-RNTI, the CS-RNTI, or the MCS-C-RNTI.

[0286] (Method 1-2)

[0287] At any time for a scheduled cell, when a C-RNTI is provided to a UE, a UE in RRC connected mode and RRC disabled mode can be expected to have received at most 16 (or N) PDCCHs for DCI formats that schedule 16 (or N) PDSCH receptions, which are CRC scrambled with the C-RNTI, the CS-RNTI, the MCS-C-RNTI, the G-RNTI for multicast, or the G-CS-RNTI, and for which the UE has not received any corresponding PDSCH symbols. Furthermore, in this case, a UE in RRC connected mode and a UE in RRC disabled mode can be expected to have received at most 16 PDCCHs for DCI formats that schedule 16 PUSCH receptions, which are CRC scrambled with the C-RNTI, the CS-RNTI, or the MCS-C-RNTI, and for which the UE has not received any corresponding PUSCH symbols.

[0288] In this regard, when a terminal receives 16 (or N) or more PDCCHs for a DCI format CRC-scrambled with G-RNTI (and G-CS-RNTI) for multicast and G-RNTI for broadcast, scheduling reception of 16 (or N) or more PDSCHs, the terminal may perform one of the following actions:

[0289] For example, a terminal may prioritize the G-RNTI for broadcast over the G-RNTI (and G-CS-RNTI) for multicast. That is, the terminal may drop all or part of the G-RNTI for broadcast.

[0290] As another example, a terminal may lower the priority of, or drop, all or part of, the G-RNTI for multicast and broadcast.

[0291] As another example, a terminal may lower the priority of, or drop, all or part of, the G-RNTI for broadcast.

[0292] Additionally or alternatively, if the terminal lowers the priority of and drops all or some of the G-RNTIs for multicast and / or broadcast, the terminal may lower the priority of and drop all or some of the G-RNTIs that have a lower (or lower) priority for multicast and / or broadcast.

[0293] Additionally or alternatively, if the terminal lowers the priority of and drops all or some of the G-RNTIs for multicast and / or broadcast, the terminal may lower the priority of and drop all or some of the G-RNTIs with lower G-RNTI values ​​for multicast and / or broadcast.

[0294] Additionally or alternatively, if the terminal lowers the priority of and drops all or some of the G-RNTIs for multicast and / or broadcast, the terminal may lower the priority of and drop all or some of the G-RNTIs with higher G-RNTI values ​​for multicast and / or broadcast.

[0295] (Method 1-3)

[0296] At any time for a scheduled cell, when a C-RNTI is provided to a UE, a UE in RRC connected mode and RRC disabled mode can be expected to have received at most 16 (or N) PDCCHs for DCI formats that are CRC scrambled with the C-RNTI, CS-RNTI, MCS-C-RNTI, G-RNTI for multicast only during RRC connected mode, or G-CS-RNTI, and that schedule 16 (or N) PDSCH receptions for which the UE has not received any corresponding PDSCH symbols. Furthermore, in this case, a UE in RRC connected mode and an RRC disabled UE can be expected to have received at most 16 PDCCHs for DCI formats that are CRC scrambled with the C-RNTI, CS-RNTI, or MCS-C-RNTI, and that schedule 16 PUSCH receptions for which the UE has not received any corresponding PUSCH symbols.

[0297] On the other hand, if the terminal is in RRC disabled mode, the terminal may have received more than 16 (or N) PDCCHs for DCI formats that schedule reception of 16 (or N) PDSCHs, CRC scrambled with at least the C-RNTI for SDT, the G-RNTI (and G-CS-RNTI) for multicast, and the G-RNTI for broadcast, and for which no corresponding PDSCH symbol has been received.

[0298] Example 2

[0299] This embodiment relates to a method for performing beam selection based on SDT (small data transmission) or RACH (random access channel) for RRC inactive (RRC_INACTIVE) mode.

[0300] Specifically, a terminal in RRC disabled mode can select a specific SSB beam index for SDT, select a RACH preamble resource / ID mapped thereto, and perform transmission, or select a CG (configured grant) PUSCH resource to perform transmission.

[0301] Additionally or alternatively, the terminal may trigger RACH to request system information, and at this time, select an SSB beam index and select a RACH preamble resource / ID mapped thereto to perform transmission.

[0302] Additionally or alternatively, the terminal may trigger RACH for initial access, and at this time, select an SSB beam index and select a RACH preamble resource / ID mapped thereto to perform transmission.

[0303] Additionally or alternatively, if the UE is in RRC connected mode or SDT is configured for the UE, the base station may transmit a UE-dedicated message, DCI, DL MAC-CE, and / or RRC release message to the UE. Through this, the base station may instruct the UE to receive multicast PDCCH / PDSCH for a specific beam index.

[0304] At this time, if the terminal is performing multicast PDCCH / PDSCH reception, the base station can expect to receive a multicast PDCCH / PDSCH for an SSB beam index mapped according to the RACH preamble and / or CG PUSCH transmission resources transmitted by the terminal, or according to an instruction of the base station. That is, the terminal can receive a multicast PDCCH / PDSCH for an SSB beam index mapped according to the RACH preamble and / or CG PUSCH transmission resources transmitted, or according to an instruction of the base station. In this regard, the base station can schedule the multicast PDCCH for the SSB beam index and other PDCCHs received by the terminal so that they are not received in an amount exceeding the capability of the terminal.

[0305] Example 3

[0306] This embodiment relates to a method for setting multiple SSB mappings for multicast PDCCH / PDSCH transmission. Specifically, this embodiment proposes a method for performing PDCCH / PDSCH transmission and reception for a G-RNTI (or G-CS-RNTI) for multicast in the direction of some SSB beam(s).

[0307] For group common transmission, if the locations of terminals within the group are known, there is no need to always multicast to all SSB beams (e.g., SSB resource index) or CSI-RS beams (e.g., CSI-RS resource index) for each service. For example, if multicast is performed only for a specific area, the base station can transmit only the multicast PDCCH / PDSCH for the SSB beam(s) or CSI-RS beam(s) directed to that specific area.

[0308] Therefore, the base station can schedule to broadcast / transmit PDCCH / PDSCH for G-RNTI for multicast only for some beam(s) according to the method described below in this embodiment.

[0309] [xХN+K] in the manner described below th PDCCH monitoring occasion(s) may be:

[0310] - [xХN+K] in a certain time window (which can be replaced by on-duration or active time). th The PDCCH monitoring opportunity(s) may correspond to the Kth transmitted SSB. Here, x is {0, 1, ..., X-1}, K is {1, 2, ..., N}, N denotes the number of SSBs actually transmitted according to the proposed method of the present disclosure, and X may be equal to CEIL (number of PDCCH monitoring opportunities within a window / N). In this case, the actually transmitted SSBs may be sequentially numbered from 1 in ascending order of the SSB index.

[0311] (Method 3-1)

[0312] The base station is within a specific time window [xХN+K] th In PDCCH monitoring opportunity(s), only N actual SSBs can be configured to be transmitted on specific SSB(s). At this time, for the time window, a specific CFR for multicast, a specific G-RNTI, a specific G-RNTI group, a specific common search space, or a specific search space group can be configured to be mapped.

[0313] In this method, the base station can configure the SSB(s) to be actually transmitted only with different SSB(s) for different time windows. For example, the base station can configure multiple time windows within a modification period, and can configure the number of SSB(s) actually transmitted (i.e., the N value) differently for each time window. In addition, the SSB index(es) of the SSB(s) actually transmitted may be configured differently for each time window. Here, the time window for a specific G-RNTI or a specific G-RNTI group for multicast can be configured to include all SSBs within the cell.

[0314] For example, the change interval can be set to 5 seconds, 100 time windows can be set within 5 seconds, and 10 G-RNTI groups or 10 G-RNTIs can be mapped to the 100 time windows. Such mapping of G-RNTI (or G-RNTI group) to time window can be set to repeat for each change interval. In this case, the base station can transmit only PDCCH / PDSCH for N_k actually transmitted SSB(s) within one or more time windows for the kth G-RNTI group or the kth G-RNTI. In addition, the multiple time windows can be repeated according to a period of P_k (e.g., 160 ms). Here, N_k can be equal to or less than the total number of SSBs in the cell. In addition, the same or different N_k and P_k values ​​can be set for different k values, and the N_k and P_k values ​​can be changed for each change interval.

[0315] In this regard, the base station can set the same or different N_k and P_k values ​​for each G-RNTI group, G-RNTI, CFR, and / or time window for each change interval. The N_k and P_k values ​​can be transmitted via MCCH once or multiple times for each change interval. In addition, the base station can set the same or different time window lengths for each G-RNTI group, G-RNTI, CFR, and / or time window for each change interval.

[0316] Alternatively, in this method, the base station can set different actual transmitted SSB(s) for different CFRs. For example, the value N, which is the number of SSBs actually transmitted, can be set differently for each CFR. In addition, the SSB index(es) of the SSB(s) actually transmitted can be set differently for each CFR. In this case, the base station can set a specific G-RNTI or a specific G-RNTI group to be mapped to a specific CFR. Alternatively, the base station can set a specific G-RNTI or a specific G-RNTI group to be mapped to a specific time window of a specific CFR.

[0317] A terminal that wishes to receive group common DCI and PDSCH for a specific G-RNTI can receive the group common DCI and PDSCH by selecting a CFR, a search space (or a search space group), and / or a time window to which the specific G-RNTI is mapped.

[0318] At this time, only N specific SSB(s) can be provided in a specific time window. For example, if SSB for a specific G-RNTI is transmitted only for SSB indices {4, 5, 6, 7}, the N value is set to 4. The base station can broadcast / transmit information about SSB indices {4, 5, 6, 7} to the terminal through an SSB-related bitmap, etc. Such settings / information can be broadcast / transmitted through MBS-related system information (e.g., MBS SIB), MCCH, or group common MAC-CE, etc.

[0319] In this regard, if the SSB index {4, 5, 6, 7} is greater than the threshold, the terminal may monitor the DCI for the G-RNTI corresponding to one or more SSBs among the SSB indices {4, 5, 6, 7}. Conversely, if the SSB index {4, 5, 6, 7} is less than the threshold, the terminal may not monitor the DCI for the corresponding G-RNTI. Here, the threshold may be separately set by the base station via SIB or MCCH. If there is no separately set threshold, the terminal may use the threshold for serving cell measurement for that purpose.

[0320] When multiple time windows are mapped to a specific G-RNTI, different time windows may provide group common transmissions for different SSBs. For example, the same G-RNTI may be mapped to a time window of SFN=5 and a time window of SFN=10, and the time window of SFN=5 may provide group common transmissions for SSB indices {4, 5}, and the time window of SFN=10 may provide group common transmissions for SSB indices {6, 7}. In this case, the terminal may select one time window according to the best SSB to receive group common transmissions.

[0321] (Method 3-2)

[0322] The base station is within a specific time window [xХN+K] th PDCCH transmissions may be configured to be performed only for specific SSB(s) during PDCCH monitoring opportunity(s). At this time, a specific CFR, a specific G-RNTI, a specific G-RNTI group, a specific search space, or a specific search space group may be configured to be mapped to the corresponding time window.

[0323] For example, a base station may be configured to perform group common DCI and group common PDSCH transmission only for specific SSB(s) for PDCCH monitoring opportunity(s) for a total of N SSBs. In this case, a terminal may perform PDCCH monitoring for a specific SSB according to a threshold, and may receive a group common PDSCH transmission scheduled by the DCI only when the group common DCI for the specific SSB is received.

[0324] Alternatively, the base station may transmit the group common DCI for all SSBs for the PDCCH monitoring opportunity(s) for all N SSBs, but may transmit the group common PDSCH only for specific SSB(s). In this case, the DCI for the SSB on which the group common PDSCH is not transmitted may indicate / indicate that the PDSCH is not transmitted. Alternatively, the DCI for the SSB on which the group common PDSCH is not transmitted may indicate / indicate that the group common PDSCH is transmitted to another SSB. In this case, the DCI may indicate TCI state information for the other SSB. In addition, the terminal performs PDCCH monitoring for a specific SSB according to a threshold, and when the terminal receives the group common DCI for the specific SSB, the terminal may receive the PDSCH if the group common PDSCH transmission scheduled by the DCI is associated with the specific SSB. In contrast, if a group common PDSCH transmission scheduled by DCI is not associated with a specific SSB, the terminal can receive the PDSCH only if the measurement value of the SSB associated with the PDSCH is greater than or equal to a threshold.

[0325] In this method, the base station can be configured to perform or not perform group common DCI or group common PDSCH transmission for the same or different SSB(s) for different time windows.

[0326] For example, the change interval can be set to 5 seconds, 100 time windows can be set within 5 seconds, and 10 G-RNTI groups or 10 G-RNTIs can be mapped to the 100 time windows. Such G-RNTI (or G-RNTI group) to time window mapping can be set to repeat for each change interval. At this time, the base station can transmit the group common DCI and / or group common PDSCH only for N_k SSBs among the total SSBs within one or more time windows for the k-th G-RNTI group or the k-th G-RNTI. At this time, the multiple time windows can be repeated according to a period of P_k (e.g., 160 ms). Here, N_k can be equal to or less than the total number of SSBs in the cell. In addition, the same or different N_k and P_k values ​​can be set for different k values, and the N_k and P_k values ​​can be changed for each change interval. In this regard, the base station may set the same or different N_k and P_k values ​​for each G-RNTI group, G-RNTI, CFR, and / or time window for each change interval. The N_k and P_k values ​​may be transmitted once or multiple times via MCCH for each change interval.

[0327] If the aforementioned time window is an MTCH window for MTCH data transmission, the terminal may perform monitoring for a PDCCH monitoring opportunity according to one or more of the following methods (hereinafter, method 3-A to method 3-D) depending on the time window setting.

[0328] (Method 3-A)

[0329] It may be considered how a particular MTCH window is mapped to one or more G-RNTIs.

[0330] For this method, the base station can map one MTCH window to one or more G-RNTIs via RRC or MAC-CE. In this case, a terminal wishing to receive a transmission for a certain G-RNTI can monitor the PDCCH in the MTCH window mapped to the corresponding G-RNTI.

[0331] Additionally or alternatively, the base station may map an MTCH window to multiple G-RNTIs according to a specific formula / rule. In this case, a terminal wishing to receive a transmission for a specific G-RNTI may determine the MTCH window mapped to the corresponding G-RNTI according to the formula / rule, and monitor the PDCCH in the determined MTCH window.

[0332] (Method 3-B)

[0333] It may be considered that there is no information that a specific MTCH window set by the base station is mapped to a specific G-RNTI.

[0334] For this method, the terminal may attempt to receive all G-RNTIs it wishes to receive during the PDCCH monitoring opportunity of the MTCH window.

[0335] Additionally or alternatively, the UE may attempt reception for a specific G-RNTI according to the DRX per G-RNTI during the PDCCH monitoring opportunity of the MTCH window. In this regard, the base station may provide the UE with separate DRX configuration information for each G-RNTI or G-RNTI group or for broadcast or all group common PDCCH. Accordingly, the UE may determine the on-duration period for the corresponding G-RNTI according to the DRX configuration of the specific G-RNTI to be received, and monitor the DCI for the corresponding G-RNTI during the determined on-duration period. At this time, the on-duration period may be defined only within the MTCH window.

[0336] Additionally or alternatively, the UE may attempt to receive a specific G-RNTI according to the search space for each G-RNTI during the PDCCH monitoring opportunity of the MTCH window. In this regard, the base station may provide the UE with separate search space configuration information for each G-RNTI or G-RNTI group, or for a broadcast or all-group common PDCCH. Accordingly, the UE may monitor the DCI for the specific G-RNTI it wishes to receive according to the search space configuration of the corresponding G-RNTI. At this time, the search space for the G-RNTI may only be defined within the MTCH window.

[0337] (Method 3-C)

[0338] A method may be considered in which group common DCI received within the MTCH window schedules group common PDSCH within the MTCH window or group common PDSCH outside the MTCH window.

[0339] For this method, the DCI can schedule the PDSCH only in the slots within the MTCH window. In this case, if the k0 value of the group common DCI received by the UE within the MTCH window (e.g., the slot offset between the DCI and the PDSCH scheduled by the DCI) is outside the MTCH window, the UE ignores the DCI and may not receive the PDSCH indicated / scheduled by the DCI. In addition, if repetition is indicated by the DCI, some PDSCH repetitions may be located outside the MTCH window. If some slots of the slot-based PDSCH repetition exist outside the MTCH window, the UE may not receive the PDSCH repetitions located outside the MTCH window depending on the configuration of the base station.

[0340] Additionally or alternatively, the DCI may schedule a PDSCH in a slot located outside the MTCH window. In this case, if the k0 value of the group common DCI received by the UE within the MTCH window (e.g., the slot offset between the DCI and the PDSCH scheduled by the DCI) is outside the MTCH window, the UE may receive a PDSCH indicated / scheduled by the DCI and located outside the MTCH window. In addition, if repetition is indicated by the DCI, some PDSCH repetitions may be located outside the MTCH window. If some slots of the slot-based PDSCH repetitions exist outside the MTCH window, the UE may receive the PDSCH repetitions located outside the MTCH window depending on the configuration of the base station.

[0341] In this regard, SSB mapping can only occur within the MTCH window. Therefore, if the k0 value of the group common DCI schedules a PDSCH outside the MTCH window, and if TCI state information is indicated by the DCI, the UE can receive the PDSCH based on the indicated TCI state information. Conversely, if TCI state information is not indicated by the DCI, the UE can receive the PDSCH based on the same SSB as the case of the DCI.

[0342] (Method 3-D)

[0343] It may be considered how a particular search space or a particular group of search spaces are mapped to one or more G-RNTIs.

[0344] For this method, the base station can map a specific search space or a specific search space group to one or more G-RNTIs via RRC or MAC-CE. In this case, a terminal wishing to receive a transmission for a specific G-RNTI can monitor the PDCCH through the specific search space or specific search space group mapped to the G-RNTI.

[0345] Additionally or alternatively, the base station may map a specific search space or a specific search space group to multiple G-RNTIs along with a specific MTCH window. In this case, a terminal wishing to receive a transmission for a specific G-RNTI can monitor the PDCCH through a specific search space or a specific search space group in the MTCH window mapped to the corresponding G-RNTI.

[0346] Based on the embodiments / methods described above in this disclosure, there is a technical effect that enables a base station to obtain information about SSB beams received by a terminal in RRC deactivation mode. Furthermore, based on the embodiments / methods described above in this disclosure, channel reception is performed according to the terminal's capabilities, thereby preventing waste of radio resources and enabling channel reception suited to the terminal's capabilities.

[0347] General devices to which the present disclosure may be applied

[0348] FIG. 12 illustrates a block diagram of a wireless communication device according to one embodiment of the present disclosure.

[0349] Referring to FIG. 12, the first wireless device (100) and the second wireless device (200) can transmit and receive wireless signals through various wireless access technologies (e.g., LTE, NR).

[0350] A first wireless device (100) includes one or more processors (102) and one or more memories (104), and may further include one or more transceivers (106) and / or one or more antennas (108). The processor (102) controls the memories (104) and / or the transceivers (106), and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in the present disclosure. For example, the processor (102) may process information in the memory (104) to generate first information / signal, and then transmit a wireless signal including the first information / signal via the transceiver (106). In addition, the processor (102) may receive a wireless signal including second information / signal via the transceiver (106), and then store information obtained from signal processing of the second information / signal in the memory (104). The memory (104) may be connected to the processor (102) and may store various information related to the operation of the processor (102). For example, the memory (104) may perform some or all of the processes controlled by the processor (102), or may store software code including commands for performing the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in the present disclosure. Here, the processor (102) and the memory (104) may be part of a communication modem / circuit / chip designed to implement a wireless communication technology (e.g., LTE, NR). The transceiver (106) may be connected to the processor (102) and may transmit and / or receive wireless signals via one or more antennas (108). The transceiver (106) may include a transmitter and / or a receiver. The transceiver (106) may be used interchangeably with an RF (Radio Frequency) unit. In the present disclosure, a wireless device may also mean a communication modem / circuit / chip.

[0351] A second wireless device (200) includes one or more processors (202), one or more memories (204), and may further include one or more transceivers (206) and / or one or more antennas (208). The processor (202) controls the memories (204) and / or the transceivers (206), and may be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in the present disclosure. For example, the processor (202) may process information in the memory (204) to generate third information / signals, and then transmit a wireless signal including the third information / signals via the transceivers (206). Furthermore, the processor (202) may receive a wireless signal including fourth information / signals via the transceivers (206), and then store information obtained from signal processing of the fourth information / signals in the memory (204). The memory (204) may be connected to the processor (202) and may store various information related to the operation of the processor (202). For example, the memory (204) may perform some or all of the processes controlled by the processor (202), or may store software code including commands for performing the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts 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 a wireless communication technology (e.g., LTE, NR). The transceiver (206) may be connected to the processor (202) and may transmit and / or receive wireless signals via one or more antennas (208). The transceiver (206) may include a transmitter and / or a receiver. The transceiver (206) may be used interchangeably with an RF unit. In the present disclosure, a wireless device may also mean a communication modem / circuit / chip.

[0352] Hereinafter, hardware elements of the wireless device (100, 200) will be described in more detail. Although not limited thereto, one or more protocol layers may be implemented by one or more processors (102, 202). For example, one or more processors (102, 202) may implement one or more layers (e.g., functional layers such as PHY, MAC, RLC, PDCP, RRC, SDAP). One or more processors (102, 202) may generate one or more Protocol Data Units (PDUs) and / or one or more Service Data Units (SDUs) according to the descriptions, functions, procedures, proposals, methods, and / or 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, procedures, proposals, methods, and / or operational flowcharts disclosed in the present disclosure. One or more processors (102, 202) can generate signals (e.g., baseband signals) including PDUs, SDUs, messages, control information, data or information according to the functions, procedures, proposals and / or methods disclosed in the present disclosure, and provide the signals to one or more transceivers (106, 206). One or more processors (102, 202) can receive signals (e.g., baseband signals) from one or more transceivers (106, 206) and obtain PDUs, SDUs, messages, control information, data or information according to the descriptions, functions, procedures, proposals, methods and / or operational flowcharts disclosed in the present disclosure.

[0353] One or more processors (102, 202) may be referred to as a controller, a microcontroller, a microprocessor, or a microcomputer. One or more processors (102, 202) may be implemented by hardware, firmware, software, or a combination thereof. For example, one or more Application Specific Integrated Circuits (ASICs), one or more Digital Signal Processors (DSPs), one or more Digital Signal Processing Devices (DSPDs), one or more Programmable Logic Devices (PLDs), or one or more Field Programmable Gate Arrays (FPGAs) may be included in one or more processors (102, 202). The descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in this disclosure may be implemented using firmware or software, and the firmware or software may be implemented to include modules, procedures, functions, etc. The descriptions, functions, procedures, proposals, methods and / or operation flowcharts disclosed in this disclosure may be implemented using firmware or software configured to perform one or more processors (102, 202) or stored in one or more memories (104, 204) and driven by one or more processors (102, 202). The descriptions, functions, procedures, proposals, methods and / or operation flowcharts disclosed in this disclosure may be implemented using firmware or software in the form of codes, instructions and / or sets of instructions.

[0354] One or more memories (104, 204) may be coupled to one or more processors (102, 202) and may store various forms of data, signals, messages, information, programs, codes, instructions, and / or commands. The one or more memories (104, 204) may be configured as ROM, RAM, EPROM, flash memory, hard drives, registers, cache memory, computer-readable storage media, and / or combinations thereof. The one or more memories (104, 204) may be located internally and / or externally to the one or more processors (102, 202). Additionally, the one or more memories (104, 204) may be coupled to the one or more processors (102, 202) via various technologies, such as wired or wireless connections.

[0355] One or more transceivers (106, 206) can transmit user data, control information, wireless signals / channels, etc., as mentioned in the methods and / or flowcharts of the present disclosure, to one or more other devices. One or more transceivers (106, 206) can receive user data, control information, wireless signals / channels, etc., as mentioned in the descriptions, functions, procedures, proposals, methods and / or flowcharts of the present disclosure, from one or more other devices. For example, one or more transceivers (106, 206) can be connected to one or more processors (102, 202) and can transmit and receive wireless signals. For example, one or more processors (102, 202) can control one or more transceivers (106, 206) to transmit user data, control information, or wireless signals to one or more other devices. Additionally, one or more processors (102, 202) may control one or more transceivers (106, 206) to receive user data, control information, or wireless signals from one or more other devices. Additionally, one or more transceivers (106, 206) may be coupled to one or more antennas (108, 208), and one or more transceivers (106, 206) may be configured to transmit and receive user data, control information, wireless signals / channels, or the like, as referred to in the descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in the present disclosure, via 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) can convert received user data, control information, wireless signals / channels, etc. from RF band signals to baseband signals in order to process the received user data, control information, wireless signals / channels, etc. using one or more processors (102, 202).One or more transceivers (106, 206) may convert user data, control information, wireless signals / channels, etc. processed by one or more processors (102, 202) from baseband signals to RF band signals. For this purpose, one or more transceivers (106, 206) may include an (analog) oscillator and / or filter.

[0356] The embodiments described above are combinations of components and features of the present disclosure in a predetermined form. Each component or feature should be considered optional unless explicitly stated otherwise. Each component or feature may be implemented without being combined with other components or features. Furthermore, it is also possible to form embodiments of the present disclosure by combining some components and / or features. The order of operations described in the embodiments of the present disclosure may be changed. Some components or features of one embodiment may be included in another embodiment or may be replaced with corresponding components or features of another embodiment. It is self-evident that claims that do not have an explicit citation relationship in the patent claims may be combined to form embodiments or incorporated as new claims through post-application amendments.

[0357] It will be apparent to those skilled in the art that the present disclosure may be embodied in other specific forms without departing from the essential characteristics thereof. Therefore, the above detailed description should not be construed as limiting in any respect, but rather as illustrative. The scope of the present disclosure should be determined by a reasonable interpretation of the appended claims, and all modifications within the scope of equivalents of the present disclosure are intended to be included within the scope of the present disclosure.

[0358] The scope of the present disclosure includes software or machine-executable instructions (e.g., an operating system, an application, firmware, a program, etc.) that cause operations according to the methods of various embodiments to be executed on a device or a computer, and a non-transitory computer-readable medium having such software or instructions stored thereon and executable on the device or computer. Instructions that can be used to program a processing system to perform the features described in the present disclosure can be stored on / in a storage medium or a computer-readable storage medium, and a computer program product including such a storage medium can be used to implement the features described in the present disclosure. The storage medium can include, but is not limited to, high-speed random access memory, such as DRAM, SRAM, DDR RAM, or other random access solid state memory devices, and can 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 remotely located from the processor(s). The memory or, alternatively, the non-volatile memory device(s) within the memory comprise a non-transitory computer-readable storage medium. The features described in this disclosure may be incorporated into software and / or firmware stored on any of the machine-readable media, which may control the hardware of the processing system and allow the processing system to interact with other mechanisms that utilize results according to 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.

[0359] Here, the wireless communication technology implemented in the wireless device (100, 200) of the present disclosure may include not only LTE, NR, and 6G, but also Narrowband Internet of Things for low-power communication. At this time, for example, NB-IoT technology may be an example of LPWAN (Low Power Wide Area Network) technology, and may be implemented with standards such as LTE Cat NB1 and / or LTE Cat NB2, and is not limited to the above-described names. Additionally or alternatively, the wireless communication technology implemented in the wireless device (XXX, YYY) of the present disclosure may perform communication based on LTE-M technology. At this time, for example, LTE-M technology may be an example of LPWAN technology, and may be called by various names such as eMTC (enhanced Machine Type Communication). For example, LTE-M technology can be implemented by at least one of various standards such as 1) LTE CAT 0, 2) LTE Cat M1, 3) LTE Cat M2, 4) LTE non-BL (non-Bandwidth Limited), 5) LTE-MTC, 6) LTE Machine Type Communication, and / or 7) LTE M, and is not limited to the above-described names. Additionally or alternatively, the wireless communication technology implemented in the wireless device (XXX, YYY) of the present disclosure can include at least one of ZigBee, Bluetooth, and Low Power Wide Area Network (LPWAN) considering low-power communication, and is not limited to the above-described names. For example, ZigBee technology can create personal area networks (PAN) related to small / low-power digital communication based on various standards such as IEEE 802.15.4, and can be called by various names.

[0360] The method proposed in this disclosure is explained with a focus on examples applied to 3GPP LTE / LTE-A and 5G systems, but can be applied to various wireless communication systems in addition to 3GPP LTE / LTE-A and 5G systems.

Claims

1. A method performed by a terminal in a wireless communication system, the method comprising: A step of selecting a specific spatial parameter by performing measurements on a plurality of spatial parameters; A step of performing uplink transmission based on the above specific spatial parameters; and A step of receiving a multicast-based downlink transmission based on the above specific spatial parameter, The above terminal is in idle mode or inactive mode based on RRC (radio resource control), A method wherein the uplink transmission comprises at least one of transmission of a preamble for random access or transmission of an uplink data channel.

2. In paragraph 1, Based on the above uplink transmission corresponding to the transmission of the preamble, A method in which the transmission of the above preamble is performed using a preamble resource or preamble identification information mapped to the above specific spatial parameter.

3. In paragraph 1, Based on the above uplink transmission corresponding to the transmission of the above uplink data channel, A method in which transmission of the above uplink data channel is performed using resources based on configured grants mapped to the specific spatial parameters.

4. In paragraph 1, A method further comprising the step of receiving information about a mapping between the multicast-based downlink transmission and the specific spatial parameter.

5. In paragraph 1, A method wherein the specific spatial parameter is based on at least one of an index of a synchronization signal block (SSB) resource or an index of a channel state information-reference signal (CSI-RS) resource.

6. In paragraph 1, For the above multicast-based downlink transmission, Among the total N spatial parameters, M (M) that include the specific spatial parameter <N)의 공간 파라미터와 관련된 적어도 하나의 모니터링 기회(monitoring occasion)가 설정되는, 방법.

7. In paragraph 6, A method wherein said at least one monitoring opportunity is located within a time window or across multiple time windows.

8. In paragraph 7, A method wherein each time window is mapped to at least one of a common frequency resource (CFR) for multicast, a group-radio network temporary identifier (G-RNTI), a G-RNTI group, a search space, or a search space group.

9. In paragraph 7, Based on the above at least one monitoring opportunity being located across multiple time windows, A method for establishing multicast-based downlink transmissions based on different spatial parameters in different time windows.

10. In paragraph 6, A method in which the above M spatial parameters are set based on a multicast-based service type.

11. In a wireless communication system, the terminal: one or more transmitters and receivers; and comprising one or more processors connected to said one or more transceivers, One or more of the above processors: Select a specific spatial parameter by performing measurements on multiple spatial parameters; Perform uplink transmission based on the above specific spatial parameters; Based on the above specific spatial parameters, set to receive multicast-based downlink transmission, The above terminal is in idle mode or inactive mode based on RRC (radio resource control), A terminal, wherein the above uplink transmission includes at least one of transmission of a preamble for random access or transmission of an uplink data channel.

12. A method performed by a base station in a wireless communication system, the method comprising: A step of receiving an uplink transmission based on a specific spatial parameter selected through measurements of a plurality of spatial parameters; and A step of performing multicast-based downlink transmission based on the above specific spatial parameters, The above terminal is in idle mode or inactive mode based on RRC (radio resource control), A method wherein the uplink transmission comprises at least one of transmission of a preamble for random access or transmission of an uplink data channel.

13. In a wireless communication system, at a base station, the base station: one or more transmitters and receivers; and comprising one or more processors connected to said one or more transceivers, One or more of the above processors: Receive an uplink transmission based on a specific spatial parameter selected through measurements of multiple spatial parameters; Based on the above specific spatial parameters, set to perform multicast-based downlink transmission, The above terminal is in idle mode or inactive mode based on RRC (radio resource control), A base station, wherein the uplink transmission includes at least one of transmission of a preamble for random access or transmission of an uplink data channel.

14. In a processing device configured to control a terminal in a wireless communication system, the processing device: one or more processors; and A processing device comprising one or more computer memories operatively connected to said one or more processors and storing instructions for performing a method according to any one of claims 1 to 10 based on execution by said one or more processors.

15. One or more non-transitory computer-readable media storing one or more instructions, A computer-readable medium, wherein the one or more commands are executed by one or more processors to control a device in a wireless communication system to perform a method according to any one of claims 1 to 10.

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