Method and apparatus for performing beam reporting on basis of radio link monitoring in wireless communication system

Abstract

The purpose of the present disclosure is to perform beam reporting on the basis of radio link monitoring in a wireless communication system, and an operation method for a terminal may comprise the steps of: establishing a connection with a base station; receiving a radio resource control (RRC) configuration message from the base station; receiving at least one reference signal from the base station; detecting a beam failure on the basis of the at least one reference signal; generating a report message on the basis of a measurement result of the at least one reference signal; and transmitting the beam report message to the base station.

Description

Method and device for performing beam reporting based on wireless link monitoring in a wireless communication system

[0001] The present disclosure relates to a device and method for performing UE-initiated / Event-driven (UI / ED) beam reporting based on wireless link monitoring in a wireless communication system.

[0002] Communication networks (e.g., 5G communication networks, 6G communication networks, etc.) are being developed to provide improved communication services compared to existing communication networks (e.g., long term evolution (LTE), advanced LTE-A (LTE-A), etc.). 5G communication networks (e.g., new radio (NR) communication networks) can support frequency bands above 6 GHz as well as frequency bands below 6 GHz. That is, 5G communication networks can support FR1 bands and / or FR2 bands. 5G communication networks can support various communication services and scenarios compared to LTE communication networks. For example, usage scenarios of 5G communication networks can include enhanced Mobile Broadband (eMBB), Ultra Reliable Low Latency Communication (URLLC), massive Machine Type Communication (mMTC), etc.

[0003] Compared to 5G, 6G communication networks can support a wider range of communication services and scenarios. 6G communication networks can meet requirements for ultra-high performance, ultra-high bandwidth, ultra-high space, ultra-high precision, ultra-intelligence, and / or ultra-reliability. 6G communication networks can support diverse and wide frequency bands and be applied to various usage scenarios (e.g., terrestrial communications, non-terrestrial communications, sidelink communications, etc.).

[0004] Meanwhile, in 5G NR, Multiple Transmission and Reception Point (mTRP) technology refers to a technique in which a base station (e.g., gNB) communicates with terminals by utilizing multiple Transmission Reception Points (TRPs) that are physically separated. MTRP technology can solve the problem of reduced Quality-of-Service (QoS) when terminals located at the cell-edge are far from the base station, and the problem of inter-cell interference from base stations located in different cells. Furthermore, MTPR technology can play a role in providing an additional communication path, a non-line-of-sight (NLOS) path, from the base station in cases where the line-of-sight (NLOS) path from the base station is limited, such as in millimeter wave bands.

[0005] Beam management for TRP in 5G NR can be defined as a set of L1 / L2 procedures that find or maintain the optimal beam required for transmission / reception of each TRP and UE. In particular, for beam management related to analog beamforming, a transmission configuration index (TCI) has been introduced to configure the UE's reception beam for a specific channel / signal, such as PDSCH / CSI-RS / PDCCH. TCI was introduced to dynamically indicate quasi-colocation (QCL) information through downlink control information (DCI) at the base station.

[0006] On the other hand, depending on the status and circumstances of the communication channel, it is necessary to switch between the uplink signal transmission method, Single Transmission and Reception Point (sTRP) mode and Multiple Transmission and Reception Point mode. However, the method and related procedures for switching between Single Transmission and Reception Point mode and Multiple Transmission and Reception Point mode are not defined. Therefore, a method for switching between Single Transmission and Reception Point mode and Multiple Transmission and Reception Point mode is required.

[0007] Meanwhile, the technology that serves as the background for the invention is written to promote understanding of the background for the invention, and may include content that is not a prior art already known to a person with ordinary skill in the field to which the technology belongs.

[0008] The present disclosure may provide a device and method for performing beam reporting of a terminal based on wireless link monitoring.

[0009] The present disclosure may provide a device and method for performing UE-initiated / Event-driven (UI / ED) beam reporting based on wireless link monitoring.

[0010] The present disclosure may provide a device and method for receiving settings related to UI / ED beam reporting.

[0011] The present disclosure may provide a device and method for performing UI / ED beam reporting through a random access procedure.

[0012] The present disclosure may provide a device and method for performing beam reporting based on beam failure detection.

[0013] The present disclosure may provide a device and method for performing UI / ED beam reporting based on a threshold different from the threshold used in beam failure detection.

[0014] The present disclosure may provide a device and method for performing beam reporting based on the number of beam failure detections.

[0015] The present disclosure may provide a device and method for performing beam reporting based on a counter for beam failure detection.

[0016] The technical objectives to be achieved in the present disclosure are not limited to those mentioned above, and other technical tasks not mentioned can be considered by a person having ordinary skill in the technical field to which the technical configuration of the present disclosure is applied from the embodiments of the present disclosure described below.

[0017] As an example of the present disclosure, a method of operating a terminal in a wireless communication system may include a step of establishing a connection with a base station, a step of receiving an RRC (radio resource control) configuration message from the base station, a step of receiving at least one reference signal from the base station, a step of detecting a beam failure based on the at least one reference signal, a step of generating a report message based on a measurement result of the at least one reference signal, and a step of transmitting the beam report message to the base station.

[0018] As an example of the present disclosure, a method of operating a base station in a wireless communication system includes the steps of establishing a connection with a terminal, transmitting an RRC (radio resource control) configuration message to the terminal, transmitting at least one reference signal to the terminal, and receiving a beam report message from the terminal, wherein a beam failure is detected based on the at least one reference signal, and the beam report message can be received in response to a beam report being triggered by the terminal based on a measurement result of the at least one reference signal.

[0019] In a wireless communication system, a terminal includes at least one transceiver, at least one processor, and at least one memory operably connected to the at least one processor and storing instructions that, when executed by the processor, control the terminal to perform operations, wherein the operations may include establishing a connection with a base station, receiving an RRC (radio resource control) configuration message from the base station, receiving at least one reference signal from the base station, detecting a beam failure based on the at least one reference signal, generating a report message based on a measurement result of the at least one reference signal, and transmitting the beam report message to the base station.

[0020] In a wireless communication system, a base station includes at least one transceiver, at least one processor, and at least one memory operably connected to the at least one processor and storing instructions that, when executed by the processor, control the base station to perform operations, the operations including: establishing a connection with a terminal; transmitting an RRC (radio resource control) configuration message to the terminal; transmitting at least one reference signal to the terminal; and receiving a beam report message from the terminal, wherein a beam failure is detected based on the at least one reference signal, and the beam report message can be received in response to a beam report being triggered by the terminal based on a measurement result of the at least one reference signal.

[0021] The above-described aspects of the present disclosure are only some of the preferred embodiments of the present disclosure, and various embodiments reflecting the technical features of the present disclosure can be derived and understood by a person having ordinary skill in the art based on the detailed description of the present disclosure to be described below.

[0022] The following effects may be achieved by embodiments based on the present disclosure.

[0023] According to the present disclosure, UE-initiated / Event-driven (UI / ED) beam reporting can be efficiently performed based on wireless link monitoring in a wireless communication system.

[0024] The present disclosure can efficiently switch the transmission method of an uplink signal based on a single uplink DCI in a wireless communication system.

[0025] The effects that can be obtained from the embodiments of the present disclosure are not limited to the effects mentioned above, and other effects not mentioned can be clearly derived and understood by those skilled in the art to which the technical configuration of the present disclosure is applied, from the description of the embodiments of the present disclosure below. In other words, unintended effects resulting from implementing the configuration described in the present disclosure can also be derived from the embodiments of the present disclosure by those skilled in the art.

[0026] The accompanying drawings are intended to aid understanding of the present disclosure and, together with detailed descriptions, may provide embodiments of the present disclosure. However, the technical features of the present disclosure are not limited to specific drawings, and the features disclosed in each drawing may be combined with each other to form new embodiments. Reference numerals in each drawing may indicate structural elements.

[0027] Figure 1 is a conceptual diagram illustrating an embodiment of a communication system.

[0028] Figure 2 is a block diagram illustrating an embodiment of a communication node constituting a communication system.

[0029] Figure 3 is a block diagram illustrating an embodiment of wireless devices performing communication.

[0030] Figure 4a is a block diagram illustrating an embodiment of a transmission path.

[0031] Figure 4b is a block diagram illustrating an embodiment of a receiving path.

[0032] Figure 5 is a conceptual diagram illustrating an embodiment of a system frame in a communication system.

[0033] Figure 6 is a conceptual diagram illustrating an embodiment of a subframe in a communication system.

[0034] Figure 7 is a conceptual diagram illustrating an embodiment of a slot in a communication system.

[0035] Figure 8 is a conceptual diagram illustrating an embodiment of time-frequency resources in a communication system.

[0036] Figure 9 illustrates an example of a QCL relationship between reference signals applicable to the present disclosure.

[0037] FIG. 10 illustrates an example of a procedure for integrating and setting a beam for multiple channels or reference signals through a unified TCI state according to one embodiment of the present disclosure.

[0038] FIG. 11 illustrates an example of a setup procedure of each layer for transmitting a TCI state in an M-TRP structure according to one embodiment of the present disclosure.

[0039] FIG. 12 illustrates a first embodiment of performing beam reporting based on BFD-RS according to one embodiment of the present disclosure.

[0040] FIG. 13 illustrates a second embodiment of performing beam reporting based on BFD-RS according to one embodiment of the present disclosure.

[0041] FIG. 14 illustrates a third embodiment of performing beam reporting based on BFD-RS according to one embodiment of the present disclosure.

[0042] FIG. 15 illustrates a fourth embodiment of performing beam reporting based on BFD-RS according to one embodiment of the present disclosure.

[0043] FIG. 16 illustrates an example of a procedure in which a terminal detects a beam failure and performs a UI / ED beam report according to one embodiment of the present disclosure.

[0044] FIG. 17 illustrates an example of a procedure for a base station to receive a UI / ED beam report according to one embodiment of the present disclosure.

[0045] This disclosure may be subject to various modifications and various embodiments. Specific embodiments are illustrated and described in detail in the drawings. However, this is not intended to limit the disclosure to specific embodiments, but rather to encompass all modifications, equivalents, and alternatives falling within the spirit and technical scope of the disclosure.

[0046] While terms such as "first" and "second" may be used to describe various components, these components should not be limited by these terms. These terms are used solely to distinguish one component from another. For example, without departing from the scope of the present disclosure, a first component could be referred to as a "second component," and similarly, a second component could also be referred to as a "first component." The term "and / or" may refer to a combination of multiple related items described herein or to any of multiple related items described herein.

[0047] In the present disclosure, “at least one of A and B” may mean “at least one of A or B” or “at least one of combinations of one or more of A and B.” Additionally, in the present disclosure, “at least one of A and B” may mean “at least one of A or B” or “at least one of combinations of one or more of A and B.”

[0048] In the present disclosure, (re)transmission may mean “transmission,” “retransmission,” or “transmission and retransmission,” (re)setting may mean “setting,” “resetting,” or “setting and resetting,” (re)connection may mean “connection,” “reconnection,” or “connection and reconnection,” and (re)connection may mean “connection,” “reconnection,” or “connection and reconnection.”

[0049] When a component is referred to as being "connected" or "connected" to another component, it should be understood that it may be directly connected or connected to that other component, but that there may be other components intervening. Conversely, when a component is referred to as being "directly connected" or "connected" to another component, it should be understood that there are no other components intervening.

[0050] The terminology used in this disclosure is only used to describe specific embodiments and is not intended to limit the present disclosure. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this disclosure, it should be understood that the terms "comprises" or "has" indicate the presence of a feature, number, step, operation, component, part, or combination thereof described in the specification, but do not preclude the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0051] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by a person of ordinary skill in the art to which this disclosure pertains. Terms defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and shall not be interpreted in an idealized or overly formal sense unless explicitly defined herein.

[0052] Hereinafter, preferred embodiments of the present disclosure will be described in more detail with reference to the attached drawings. In order to facilitate an overall understanding in describing the present disclosure, the same reference numerals will be used for identical components in the drawings, and redundant descriptions of identical components will be omitted. In addition to the embodiments explicitly described in the present disclosure, operations may be performed according to combinations of embodiments, extensions of embodiments, and / or modifications of embodiments. The performance of some operations may be omitted, and the order of operation may be changed.

[0053] In an embodiment, even if a method (e.g., transmitting or receiving a signal) performed by a first communication node among communication nodes is described, a corresponding second communication node can perform a method (e.g., receiving or transmitting a signal) corresponding to the method performed by the first communication node. That is, if an operation of a UE (user equipment) is described, a corresponding base station can perform an operation corresponding to the operation of the UE. Conversely, if an operation of a base station is described, a corresponding UE can perform an operation corresponding to the operation of the base station.

[0054] A base station may be referred to as a NodeB, an evolved NodeB, a gNodeB (next generation node B), a gNB, a device, an apparatus, a node, a communication node, a BTS (base transceiver station), a RRH (radio remote head), a TRP (transmission reception point), a RU (radio unit), an RSU (road side unit), a radio transceiver, an access point, an access node, etc. A UE may be referred to as a terminal, a device, an apparatus, a node, a communication node, an end node, an access terminal, a mobile terminal, a station, a subscriber station, a mobile station, a portable subscriber station, an OBU (on-broad unit), etc.

[0055] In the present disclosure, signaling may be at least one of upper layer signaling, MAC signaling, or PHY (physical) signaling. A message used for upper layer signaling may be referred to as an "upper layer message" or an "upper layer signaling message." A message used for MAC signaling may be referred to as a "MAC message" or a "MAC signaling message." A message used for PHY signaling may be referred to as a "PHY message" or a "PHY signaling message." Upper layer signaling may refer to a transmission and reception operation of system information (e.g., a master information block (MIB), a system information block (SIB)) and / or a radio resource control (RRC) message. MAC signaling may refer to a transmission and reception operation of a MAC control element (CE). PHY signaling may refer to a transmission and reception operation of control information (e.g., downlink control information (DCI), uplink control information (UCI), sidelink control information (SCI)).

[0056] In the present disclosure, “an operation (e.g., a transmission operation) is set” may mean that “setting information for the operation (e.g., an information element, a parameter)” and / or “information instructing the performance of the operation” is signaled. “An information element (e.g., a parameter) is set” may mean that the information element is signaled. In the present disclosure, “a signal and / or a channel” may mean a signal, a channel, or “a signal and a channel,” and a signal may be used to mean “a signal and / or a channel.”

[0057] The communication networks to which the embodiments are applied are not limited to those described below, and the embodiments may be applied to various communication networks (e.g., 4G communication networks, 5G communication networks, and / or 6G communication networks). Here, the term "communication network" may be used interchangeably with the term "communication system."

[0058] Figure 1 is a conceptual diagram illustrating an embodiment of a communication system.

[0059] Referring to FIG. 1, the communication system (100) may include a plurality of communication nodes (110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-4, 130-5, 130-6). In addition, the communication system (100) may further include a core network (e.g., a serving-gateway (S-GW), a packet data network (PDN)-gateway (P-GW), a mobility management entity (MME)). If the communication system (100) is a 5G communication system (e.g., a new radio (NR) system), the core network may include an access and mobility management function (AMF), a user plane function (UPF), a session management function (SMF), etc.

[0060] A plurality of communication nodes (110 to 130) can support a communication protocol (e.g., LTE communication protocol, LTE-A communication protocol, NR communication protocol, etc.) specified in the 3GPP (3rd generation partnership project) standard. The plurality of communication nodes (110 to 130) may support CDMA (code division multiple access) technology, WCDMA (wideband CDMA) technology, TDMA (time division multiple access) technology, FDMA (frequency division multiple access) technology, OFDM (orthogonal frequency division multiplexing) technology, Filtered OFDM technology, CP (cyclic prefix)-OFDM technology, DFT-s-OFDM (discrete Fourier transform-spread-OFDM) technology, OFDMA (orthogonal frequency division multiple access) technology, SC (single carrier)-FDMA technology, NOMA (non-orthogonal multiple access) technology, GFDM (generalized frequency division multiplexing) technology, FBMC (filter bank multi-carrier) technology, UFMC (universal filtered multi-carrier) technology, SDMA (space division multiple access) technology, etc. Each of the plurality of communication nodes may have the following structure.

[0061] Figure 2 is a block diagram illustrating an embodiment of a communication node constituting a communication system.

[0062] FIG. 2 is a diagram illustrating an example of a wireless device (200) in a wireless communication system according to one embodiment of the present disclosure. The wireless device (200) according to the embodiment of the present disclosure may be a mobile terminal such as a smartphone, tablet PC, or wearable device, but is not limited thereto.

[0063] Referring to FIG. 2, the wireless device (200) may include at least one control unit (210), at least one memory (220), at least one power supply unit (230), at least one transceiver unit (240), at least one input unit (250), at least one output unit (260), and / or at least one antenna (270).

[0064] The control unit (210) can control the memory (220) and / or the transceiver unit (240), and can be configured to implement the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in the present disclosure. The memory (220) can be connected to the control unit (210) and can store various information related to the operation of the control unit (210). For example, the memory (220) can perform some or all of the controls controlled by the control unit (210), or store software code including commands for performing the descriptions, functions, procedures, proposals, methods, and / or operation flowcharts disclosed in the present disclosure. The configuration of the memory is not limited in a specific manner. For example, it can be configured as at least one of a read-only memory (ROM) and a random access memory (RAM).

[0065] At least one control unit (210) may be referred to as a controller, a microcontroller, a microprocessor, or a microcomputer. The descriptions, functions, procedures, proposals, methods, and / or operational flowcharts disclosed in the present disclosure may be implemented using firmware or software in the form of codes, instructions, and / or a set of instructions. Here, the firmware or software may execute another program stored in a memory (220), such as an OS. The control unit (210) may be implemented to support beamforming or directional routing operations in which signals from at least one antenna (270) are weighted differently to effectively steer signals outgoing in a desired direction.

[0066] Additionally, at least one control unit (210) may be coupled to a backhaul or network interface. The wireless device (200) may communicate with other wireless devices through the backhaul or network interface. The control unit (210) may include at least one processor. The processor may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which methods according to embodiments of the present disclosure are performed.

[0067] At least one transceiver (240) may be connected to the control unit (210) and may transmit and / or receive a wireless signal via at least one antenna (270). The transceiver (240) may include a transmitter and / or a receiver. The at least one transceiver (240) may transmit user data, control information, wireless signals / channels, etc. mentioned in the methods and / or operation flowcharts of the present disclosure to at least one other device. For example, the at least one transceiver (240) may be connected to at least one control unit (210) and may transmit and receive wireless signals. In addition, the at least one control unit (210) may control the at least one transceiver (240) to transmit user data, control information, or a wireless signal to at least one other device. The at least one transmitter (240) may receive a signal transmitted by another wireless device from at least one antenna (270). Additionally, at least one transceiver (24) may downconvert or upconvert the received signal to generate a baseband signal. At least one antenna (270) may be a plurality of physical antennas or a plurality of logical antennas (e.g., antenna ports).

[0068] The input unit (250) can obtain information such as user input, video, and audio, and can include various input means such as various mechanical / electronic input means, cameras, and microphones. The output unit (260) is for providing information to users by generating output related to sight, hearing, or touch, and can include a display, a speaker, a vibration module, and the like. The wireless device (200) supplies power through the power supply unit (230), and the power supply unit (230) can include a wired / wireless charging circuit, a battery, and the like.

[0069] Referring again to FIG. 1, the communication system (100) may include a plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) and a plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6). Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) may form a macro cell. Each of the fourth base station (120-1) and the fifth base station (120-2) may form a small cell. The fourth base station (120-1), the third terminal (130-3), and the fourth terminal (130-4) may be within the cell coverage of the first base station (110-1). The second terminal (130-2), the fourth terminal (130-4), and the fifth terminal (130-5) may be within the cell coverage of the second base station (110-2). The fifth base station (120-2), the fourth terminal (130-4), the fifth terminal (130-5), and the sixth terminal (130-6) may be within the cell coverage of the third base station (110-3). The first terminal (130-1) may be within the cell coverage of the fourth base station (120-1). The sixth terminal (130-6) may be within the cell coverage of the fifth base station (120-2).

[0070] Here, each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be referred to as a NodeB (NB), an evolved NodeB (eNB), a gNB, an advanced base station (ABS), a high reliability-base station (HR-BS), a base transceiver station (BTS), a radio base station, a radio transceiver, an access point, an access node, a radio access station (RAS), a mobile multihop relay-base station (MMR-BS), a relay station (RS), an advanced relay station (ARS), a high reliability-relay station (HR-RS), a home NodeB (HNB), a home eNodeB (HeNB), a road side unit (RSU), a radio remote head (RRH), a transmission point (TP), a transmission and reception point (TRP), etc.

[0071] Each of the plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) may be referred to as a user equipment (UE), terminal equipment (TE), advanced mobile station (AMS), high reliability-mobile station (HR-MS), terminal, access terminal, mobile terminal, station, subscriber station, mobile station, portable subscriber station, node, device, on board unit (OBU), etc.

[0072] Meanwhile, each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may operate in a different frequency band or may operate in the same frequency band. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be connected to each other via an ideal backhaul link or a non-ideal backhaul link, and may exchange information with each other via the ideal backhaul link or the non-ideal backhaul link. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may be connected to the core network via the ideal backhaul link or the non-ideal backhaul link. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) can transmit a signal received from the core network to the corresponding terminal (130-1, 130-2, 130-3, 130-4, 130-5, 130-6), and can transmit a signal received from the corresponding terminal (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) to the core network.

[0073] Additionally, each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) may support MIMO transmission (e.g., single user (SU)-MIMO, multi user (MU)-MIMO, massive MIMO, etc.), coordinated multipoint (CoMP) transmission, carrier aggregation (CA) transmission, transmission in an unlicensed band, sidelink communication (e.g., device to device communication (D2D), proximity services (ProSe)), Internet of Things (IoT) communication, dual connectivity (DC), etc. Here, each of the plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) can perform an operation corresponding to the base station (110-1, 110-2, 110-3, 120-1, 120-2) and an operation supported by the base station (110-1, 110-2, 110-3, 120-1, 120-2). For example, the second base station (110-2) can transmit a signal to the fourth terminal (130-4) based on the SU-MIMO scheme, and the fourth terminal (130-4) can receive a signal from the second base station (110-2) by the SU-MIMO scheme. Alternatively, the second base station (110-2) can transmit signals to the fourth terminal (130-4) and the fifth terminal (130-5) based on the MU-MIMO method, and each of the fourth terminal (130-4) and the fifth terminal (130-5) can receive signals from the second base station (110-2) based on the MU-MIMO method.

[0074] Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) can transmit a signal to the fourth terminal (130-4) based on the CoMP scheme, and the fourth terminal (130-4) can receive a signal from the first base station (110-1), the second base station (110-2), and the third base station (110-3) based on the CoMP scheme. Each of the plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) can transmit and receive a signal with terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) within its cell coverage based on the CA scheme. Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) can control sidelink communication between the fourth terminal (130-4) and the fifth terminal (130-5), and each of the fourth terminal (130-4) and the fifth terminal (130-5) can perform sidelink communication under the control of the second base station (110-2) and the third base station (110-3), respectively.

[0075] Meanwhile, communication nodes performing communication in a communication network may be configured as follows. The communication node illustrated in FIG. 3 may be a specific embodiment of the wireless device illustrated in FIG. 2.

[0076] Figure 3 is a block diagram illustrating an embodiment of wireless devices performing communication.

[0077] Referring to FIG. 3, each of the first wireless device (300a) and the second wireless device (300b) may be a base station or a UE. The first wireless device (300a) may transmit a signal to the second wireless device (300b). The transmission processor (311) included in the first wireless device (300a) may receive data (e.g., a data unit) from a data source (310). The transmission processor (311) may receive control information from the controller (316). The control information may include at least one of system information, RRC configuration information (e.g., information set by RRC signaling), MAC control information (e.g., MAC CE), or PHY control information (e.g., DCI, SCI).

[0078] The transmitting processor (311) may perform a processing operation on data (e.g., an encoding operation, a symbol mapping operation, etc.) to generate data symbol(s). The transmitting processor (311) may perform a processing operation on control information (e.g., an encoding operation, a symbol mapping operation, etc.) to generate control symbol(s). In addition, the transmitting processor (311) may generate synchronization / reference symbol(s) for a synchronization signal and / or a reference signal.

[0079] The Tx MIMO processor (312) may perform a spatial processing operation (e.g., a precoding operation) on data symbol(s), control symbol(s), and / or synchronization / reference symbol(s). The output (e.g., a symbol stream) of the Tx MIMO processor (312) may be provided to modulators (MODs) included in the transceivers (313a to 313t). The modulators (MODs) may perform a processing operation on the symbol stream to generate modulation symbols, and may perform an additional processing operation (e.g., an analog conversion operation, an amplification operation, a filtering operation, an upconversion operation) on the modulation symbols to generate signals. The signals generated by the modulators (MODs) of the transceivers (313a to 313t) may be transmitted via the antennas (314a to 314t).

[0080] Signals transmitted by the first wireless device (300a) may be received by the antennas (364a to 364r) of the second wireless device (300b). The signals received by the antennas (364a to 364r) may be provided to demodulators (DEMODs) included in the transceivers (363a to 363r). The demodulator (DEMOD) may perform a processing operation (e.g., a filtering operation, an amplification operation, a downconversion operation, a digital conversion operation) on the signal to obtain samples. The demodulator (DEMOD) may perform an additional processing operation on the samples to obtain symbols. The MIMO detector (362) may perform a MIMO detection operation on the symbols. The receiving processor (361) may perform a processing operation (e.g., a deinterleaving operation, a decoding operation) on the symbols. The output of the receiving processor (361) may be provided to a data sink (360) and a controller (366). For example, data may be provided to the data sink (360), and control information may be provided to the controller (366).

[0081] Meanwhile, the second wireless device (300b) can transmit a signal to the first wireless device (300a). The transmitting processor (368) included in the second wireless device (300b) can receive data (e.g., data units) from a data source (367) and perform a processing operation on the data to generate data symbol(s). The transmitting processor (368) can receive control information from the controller (366) and perform a processing operation on the control information to generate control symbol(s). In addition, the transmitting processor (368) can perform a processing operation on a reference signal to generate reference symbol(s).

[0082] The Tx MIMO processor (369) may perform spatial processing operations (e.g., precoding operations) on data symbol(s), control symbol(s), and / or reference symbol(s). The output (e.g., symbol stream) of the Tx MIMO processor (369) may be provided to modulators (MODs) included in the transceivers (363a to 363t). The modulators (MODs) may perform processing operations on the symbol streams to generate modulation symbols, and may perform additional processing operations (e.g., analog conversion operations, amplification operations, filtering operations, upconversion operations) on the modulation symbols to generate signals. The signals generated by the modulators (MODs) of the transceivers (363a to 363t) may be transmitted via the antennas (364a to 364t).

[0083] Signals transmitted by the second wireless device (300b) may be received by the antennas (314a to 314r) of the first wireless device (300a). The signals received by the antennas (314a to 314r) may be provided to demodulators (DEMODs) included in the transceivers (313a to 313r). The demodulator (DEMOD) may perform a processing operation (e.g., a filtering operation, an amplification operation, a downconversion operation, a digital conversion operation) on the signal to obtain samples. The demodulator (DEMOD) may perform an additional processing operation on the samples to obtain symbols. The MIMO detector (320) may perform a MIMO detection operation on the symbols. The receiving processor (319) may perform a processing operation (e.g., a deinterleaving operation, a decoding operation) on the symbols. The output of the receiving processor (319) may be provided to a data sink (318) and a controller (316). For example, data may be provided to the data sink (318) and control information may be provided to the controller (316).

[0084] Memories (315 and 365) can store data, control information, and / or program code. Scheduler (317) can perform scheduling operations for communication. The processors (311, 312, 319, 361, 368, 369) and controllers (316, 366) illustrated in FIG. 3 may be the processor (210) illustrated in FIG. 2 and may be used to perform the methods described in the present disclosure.

[0085] Fig. 4a is a block diagram illustrating an embodiment of a transmission path, and Fig. 4b is a block diagram illustrating an embodiment of a reception path.

[0086] Referring to FIGS. 4A and 4B, a transmission path (410) may be implemented in a communication node that transmits a signal, and a reception path (420) may be implemented in a communication node that receives a signal. The transmission path (410) may include a channel coding and modulation block (411), an S-to-P (serial-to-parallel) block (512), an N IFFT (Inverse Fast Fourier Transform) block (413), a P-to-S (parallel-to-serial) block (414), a CP (cyclic prefix) addition block (415), and an UC (up-converter) (UC) (416). The receiving path (420) may include a DC (down-converter) (421), a CP removal block (422), an S-to-P block (423), an N FFT block (424), a P-to-S block (425), and a channel decoding and demodulation block (426). Here, N may be a natural number.

[0087] In the transmission path (410), information bits may be input to a channel coding and modulation block (411). The channel coding and modulation block (411) may perform a coding operation (e.g., a low-density parity check (LDPC) coding operation, a polar coding operation, etc.) and a modulation operation (e.g., a quadrature phase shift keying (QPSK), a quadrature amplitude modulation (QAM), etc.) on the information bits. The output of the channel coding and modulation block (411) may be a sequence of modulation symbols.

[0088] The S-to-P block (412) can convert modulation symbols in the frequency domain into parallel symbol streams to generate N parallel symbol streams. N can be an IFFT size or an FFT size. The N IFFT block (413) can perform an IFFT operation on the N parallel symbol streams to generate signals in the time domain. The P-to-S block (414) can convert the output (e.g., parallel signals) of the N IFFT block (413) into a serial signal to generate a serial signal.

[0089] The CP addition block (415) can insert a CP into a signal. The UC (416) can up-convert the frequency of the output of the CP addition block (415) to an RF (radio frequency) frequency. Additionally, the output of the CP addition block (415) can be filtered at the baseband before up-conversion.

[0090] A signal transmitted from a transmission path (410) may be input to a reception path (420). An operation in the reception path (420) may be the reverse operation of the operation in the transmission path (410). A DC (421) may down-convert the frequency of the received signal to a baseband frequency. A CP removal block (422) may remove a CP from a signal. The output of the CP removal block (422) may be a serial signal. An S-to-P block (423) may convert the serial signal into parallel signals. An N FFT block (424) may perform an FFT algorithm to generate N parallel signals. A P-to-S block (425) may convert the parallel signals into a sequence of modulation symbols. A channel decoding and demodulation block (426) may perform a demodulation operation on the modulation symbols and perform a decoding operation on the result of the demodulation operation to restore data.

[0091] In FIGS. 4A and 4B , Discrete Fourier Transform (DFT) and Inverse DFT (IDFT) may be used instead of FFT and IFFT. Each of the blocks (e.g., components) in FIGS. 4A and 4B may be implemented by at least one of hardware, software, or firmware. For example, some of the blocks in FIGS. 4A and 4B may be implemented by software, and the remaining blocks may be implemented by hardware or a “combination of hardware and software.” In FIGS. 4A and 4B , a block may be subdivided into multiple blocks, multiple blocks may be integrated into a single block, some blocks may be omitted, and blocks supporting other functions may be added.

[0092] Figure 5 is a conceptual diagram illustrating an embodiment of a system frame in a communication system.

[0093] Referring to FIG. 5, time resources in a communication system can be divided into frame units. For example, system frames can be set consecutively in the time domain of the communication system. The length of a system frame can be 10 ms (milliseconds). The system frame number (SFN) can be set from #0 to #1023. In this case, 1024 system frames can be repeated in the time domain of the communication system. For example, the SFN of the system frame after system frame #1023 can be #0.

[0094] A system frame may include two half frames. A half frame may be 5 ms long. A half frame located at the beginning of the system frame may be referred to as "half frame #0," and a half frame located at the end of the system frame may be referred to as "half frame #1." A system frame may include 10 subframes. A subframe may be 1 ms long. The 10 subframes within a system frame may be referred to as "subframes #0-9."

[0095] Figure 6 is a conceptual diagram illustrating an embodiment of a subframe in a communication system.

[0096] Referring to FIG. 6, one subframe may include n slots, where n may be a natural number. Accordingly, one subframe may be composed of one or more slots.

[0097] Figure 7 is a conceptual diagram illustrating an embodiment of a slot in a communication system.

[0098] Referring to Figure 7, a single slot may include one or more symbols. A single slot illustrated in Figure 7 may include 14 symbols. The length of a slot may vary depending on the number and length of symbols contained in the slot. Alternatively, the length of a slot may vary depending on the numerology.

[0099] In a communication system, the numerology applied to physical signals and channels may be variable. The numerology may be variable to meet various technical requirements of the communication system. In a communication system applying CP (cyclic prefix)-based OFDM waveform technology, the numerology may include subcarrier spacing and CP length (or CP type). Table 1 may be an embodiment of a method for configuring a numerology for a CP-OFDM-based communication system. At least some of the numerologies in Table 1 may be supported depending on the frequency band in which the communication system operates. In addition, the communication system may additionally support numerologies not listed in [Table 1].

[0100] Subcarrier spacing 15 ㎑ 30 ㎑ 60 ㎑ 120 ㎑ 240 ㎑ 480 ㎑ OFDM symbol length [㎲] 66.733.316.78.34.22.1 CP length [㎲] 4.762.381.190.600.300.151 Number of OFDM symbols in ㎳ 142856112224448

[0101] When the subcarrier spacing is 15 kHz (e.g., μ=0), the slot length can be 1 ms. In this case, one system frame can contain 10 slots. When the subcarrier spacing is 30 kHz (e.g., μ=1), the slot length can be 0.5 ms. In this case, one system frame can contain 20 slots. When the subcarrier spacing is 60 kHz (e.g., μ=2), the slot length can be 0.25 ms. In this case, one system frame can contain 40 slots. When the subcarrier spacing is 120 kHz (e.g., μ=3), the slot length can be 0.125 ms. In this case, one system frame can contain 80 slots. When the subcarrier spacing is 240 kHz (e.g., μ=4), the slot length can be 0.0625 ms. In this case, one system frame can contain 160 slots.

[0102] A symbol may be configured as a downlink (DL) symbol, a flexible (FL) symbol, or an uplink (UL) symbol. A slot consisting solely of DL symbols may be referred to as a "DL slot," a slot consisting solely of FL symbols may be referred to as an "FL slot," and a slot consisting solely of UL symbols may be referred to as a "UL slot."

[0103] The slot format can be semi-statically configured by higher layer signaling (e.g., RRC signaling). Information indicating the semi-static slot format can be included in the system information, and the semi-static slot format can be configured cell-specifically. In addition, the semi-static slot format can be additionally configured for each terminal through terminal-specific higher layer signaling (e.g., RRC signaling). The flexible symbol of the cell-specifically configured slot format can be overridden to a downlink symbol or an uplink symbol by terminal-specific higher layer signaling. In addition, the slot format can be dynamically indicated by physical layer signaling (e.g., a slot format indicator (SFI) included in DCI). The semi-statically configured slot format can be overridden by a dynamically indicated slot format. For example, the semi-statically configured flexible symbol can be overridden to a downlink symbol or an uplink symbol by the SFI.

[0104] The reference signal may be a channel state information-reference signal (CSI-RS), a sounding reference signal (SRS), a demodulation-reference signal (DM-RS), a phase tracking-reference signal (PT-RS), etc. The channel may be a physical broadcast channel (PBCH), a physical downlink control channel (PDCCH), a physical downlink shared channel (PDSCH), a physical uplink control channel (PUCCH), a physical uplink shared channel (PUSCH), a physical sidelink control channel (PSCCH), a physical sidelink shared channel (PSSCH), etc. In the present disclosure, the control channel may mean a PDCCH, a PUCCH, or a PSCCH, and the data channel may mean a PDSCH, a PUSCH, or a PSSCH.

[0105] Figure 8 is a conceptual diagram illustrating an embodiment of time-frequency resources in a communication system.

[0106] Referring to FIG. 8, a resource consisting of one symbol (e.g., an OFDM symbol) in the time domain and one subcarrier in the frequency domain may be defined as a "RE (resource element)". Resources consisting of one OFDM symbol in the time domain and K subcarriers in the frequency domain may be defined as a "REG (resource element group)". A REG may include K REs. A REG may be used as a basic unit for resource allocation in the frequency domain. K may be a natural number. For example, K may be 12. N may be a natural number. In the slot illustrated in FIG. 7, N may be 14. N OFDM symbols may be used as a basic unit for resource allocation in the time domain.

[0107] In the present disclosure, RB may mean CRB (common RB). Alternatively, RB may mean PRB or VRB (virtual RB). In a communication system, CRB may mean RB that constitutes a set of consecutive RBs (e.g., a common RB grid) based on a reference frequency (e.g., point A). Carriers and / or bandwidth portions may be arranged on the common RB grid. That is, the carrier and / or bandwidth portions may be composed of CRB(s). RBs or CRBs that constitute the bandwidth portions may be referred to as PRBs, and within the bandwidth portions, the CRB index may be appropriately converted to the PRB index.

[0108] Downlink data can be transmitted via the PDSCH. The base station can transmit PDSCH configuration information (e.g., scheduling information) to the terminal via the PDCCH. The terminal can obtain the PDSCH configuration information by receiving the PDCCH (e.g., downlink control information (DCI)). For example, the PDSCH configuration information can include the MCS (modulation coding scheme) used for transmitting and receiving the PDSCH, time resource information of the PDSCH, frequency resource information of the PDSCH, feedback resource information for the PDSCH, etc. The PDSCH can refer to a radio resource through which downlink data is transmitted and received. Alternatively, the PDSCH can refer to the downlink data itself. The PDCCH can refer to a radio resource through which downlink control information (e.g., DCI) is transmitted and received. Alternatively, the PDCCH can refer to the downlink control information itself.

[0109] A terminal can perform a monitoring operation on the PDCCH to receive a PDSCH transmitted from a base station. The base station can inform the terminal of the configuration information for the PDCCH monitoring operation using a higher layer message (e.g., an RRC (radio resource control) message). The configuration information for the PDCCH monitoring operation can include CORESET (control resource set) information and search space information.

[0110] CORESET information may include PDCCH DMRS (demodulation reference signal) information, PDCCH precoding information, PDCCH opportunity information, etc. The PDCCH DMRS may be a DMRS used to demodulate the PDCCH. The PDCCH opportunity may be a region where the PDCCH can exist. In other words, the PDCCH opportunity may be a region where DCI can be transmitted. The PDCCH opportunity may be referred to as a PDCCH candidate. The PDCCH opportunity information may include time resource information and frequency resource information of the PDCCH opportunity. In the time domain, the length of the PDCCH opportunity may be indicated in symbol units. In the frequency domain, the size of the PDCCH opportunity may be indicated in RB units (e.g., in PRB (physical resource block) units or CRB (common resource block) units).

[0111] The search space information may include a coreset identifier (ID) associated with the search space, a period of PDCCH monitoring, and / or an offset. Each of the PDCCH monitoring period and offset may be indicated on a slot-by-slot basis. In addition, the search space information may further include an index of the symbol at which the PDCCH monitoring operation begins.

[0112] A base station can configure a bandwidth part (BWP) for downlink communication. The BWP can be configured differently for each terminal. The base station can inform the terminal of the BWP configuration information using higher layer signaling. The higher layer signaling can mean "transmission operation of system information" and / or "transmission operation of RRC (radio resource control) message." The number of BWPs configured for one terminal can be one or more. The terminal can receive BWP configuration information from the base station and check the BWP(s) configured by the base station based on the BWP configuration information. When multiple BWPs are configured for downlink communication, the base station can activate one or more BWPs among the multiple BWPs. The base station can transmit the configuration information of the activated BWP(s) to the terminal using at least one of higher layer signaling, a medium access control (MAC) control element (CE), or DCI. The base station can perform downlink communication using the activated BWP(s). The terminal can identify the activated BWP(s) by receiving configuration information of the activated BWP(s) from the base station, and perform a downlink reception operation in the activated BWP(s).

[0113] Multiple Transmission and Reception Point (MTRP) technology refers to a technique in which a base station (e.g., gNB) communicates with a terminal by utilizing multiple transmission reception points (TRPs) that are physically separated. By utilizing multiple TRPs, MTRP technology can solve the problem of reduced quality-of-service (QoS) for terminals located at the cell edge when they are far from the base station, while also resolving the problem of inter-cell interference from base stations located in different cells. Furthermore, MTRP technology can play a role in providing an additional communication path, that is, a non-line-of-sight (NLOS) path, from the base station in cases where the line-of-sight (LOS) path from the base station is limited, such as in millimeter wave bands.

[0114] In the standard, MTRP technology is divided into Coherent Joint Transmission (CJT) and Non-Coherent Joint Transmission (NCJT). The CJT method allows two or more TRPs to cooperate in a synchronized manner to support data transmission to a single terminal based on a stable backhaul link between base stations connected to the TRPs. On the other hand, the NCJT method allows two or more TRPs to decide scheduling, precoding matrix selection, modulation, and coding schemes without cooperation between the TRPs in a situation where two or more TRPs support a single terminal.

[0115] Beam management for TRP in 5G NR can be defined as a set of L1 / L2 procedures that find or maintain the optimal beam required for transmission / reception at each TRP and terminal. Beam management procedures can be broadly categorized into four categories, as follows:

[0116] 1) Beam determination

[0117] 2) Beam measurement

[0118] 3) Beam reporting

[0119] 4) Beam sweeping

[0120] Here, the TRP and the UE can utilize the reciprocity characteristics of the downlink (DL) / uplink (UL) channels when managing beams. For example, the UE can utilize the values ​​measured in the receive beams (Rx beams) of the DL channel when configuring the transmit beam (Tx beam). And, the UE can utilize the values ​​measured in the transmit beams (Tx beams) of the UL channel when configuring the receive beam (Rx beam). These transmit beam configuration and receive beam configuration procedures can be performed in the same manner for the base station as for the UE. In particular, a transmission configuration indicator (TCI) has been introduced for beam management related to analog beamforming. The TCI can be used to configure a beam to be used for transmission of a specific channel and / or signal, for example, PDSCH and / or CSI-RS and / or PDCCH. The base station can dynamically indicate quasi-colocation (QCL) information to the UE by transmitting TCI through downlink control information (DCI).

[0121] Two antenna ports are said to be quasi-co-located when the channel characteristics of a symbol transmitted from one antenna port can be inferred from the channel characteristics of a symbol transmitted from the other antenna port. For convenience of explanation, in the following, when two antenna ports are quasi-co-located, we refer to them as having a QCL relationship.

[0122] Figure 9 illustrates an example of a QCL relationship between reference signals applicable to the present disclosure.

[0123] Referring to Fig. 9, the QCL relationship between reference signals below 5G can be extended to generate information about the TCI state.

[0124] The synchronization signal block (SSB) can be used by terminals to synchronize with the network and acquire basic information. The SSB can be in a QCL relationship with the tracking reference signal (TRS). Therefore, when receiving the TRS, at least one of the Doppler shift, delay average, and spatial characteristics of the SSB can be utilized.

[0125] CSI-RS (channel state information - reference signal): CSI-RS can be used by the network to determine the characteristics of the wireless channel. There are two types of CSI-RS. CSI-RS (CSI ACQ) can be used for CSI reception, and CSI-RS (BM) can be used for beam management (BM).

[0126] SSB and CSI-RS (BM) may be in a QCL relationship with CSI-RS (CSI ACQ), and at least one of the average and spatial characteristics of Doppler shift and delay may be utilized for CSI-RS (CSI ACQ) reception.

[0127] CSI-RS(BM) and SSB may have a QCL relationship with PDCCH DMRS (physical downlink control channel demodulation reference signal), and at least one of Doppler shift / spread and average / spread and spatial characteristics of delay may be utilized for reception of PDCCH DMRS.

[0128] SSB, CSI-RS (BM) and CSI-RS (CSI ACQ) may be in a QCL relationship with PDSCH DMRS, and at least one of the mean / spread and spatial characteristics of Doppler shift / spread and delay may be utilized for reception of PDCCH DMRS.

[0129] 3GGP Rel-17 introduced a TCI configuration method utilizing a unified TCI pool, or the unified TCI framework, to reduce signaling overhead for QCL configuration of DL and / or UL channels and simplify multi-beam operation compared to the previous release of 3GGP Rel-16.

[0130] According to the unified TCI framework, the base station can preset a common TCI pool that can be commonly used (or applied) for DL ​​and UL channels via RRC signaling. Furthermore, according to the unified TCI framework, the base station can directly indicate TCI for DL ​​and UL channels from the configured common TCI pool using the Medium Access Control (MAC) control element (CE) (MAC-CE) / downlink control information (DCI). Furthermore, according to the unified TCI framework, the base station can support updates to the common TCI state.

[0131] A common TCI state can be indicated (or set) for multiple component carriers (CCs). Among the multiple CCs, a reference CC can be additionally set, and TCI updates for other CCs within the indicated list can be performed simultaneously via a TCI update command for the reference CC.

[0132] At this time, there are three main methods for setting the status of TCI for DL ​​channels and UL channels.

[0133] A. Joint TCI state indication method that is commonly indicated to DL / UL channels

[0134] B. DL channel separate TCI state indication method for setting TCI separately for DL ​​channel and

[0135] C. UL Channel Separate TCI State Indication Method

[0136] Looking at the three methods above from a broader perspective, they can be divided into a joint TCI status indication method that provides common indications for both DL and UL channels, and a separate TCI status indication method that sets TCIs separately for each DL or UL channel. The fundamental difference between the two methods above lies in the existence of reciprocity between the DL and UL channels.

[0137] The Unified TCI framework was designed for a single TRP (sTRP) system in 3GPP Rel-17. However, 3GPP Rel-18 aims to expand to a multi-TRP (mTRP) system.

[0138] TCI status can be used to convey QCL relationships to terminals. TCI status contains information about QCL relationships and can be conveyed via DCI. Section 5.1.5 of 3GPP TS 38.214 defines the procedure for conveying QCL information as follows:

[0139]

[0140]

[0141]

[0142]

[0143]

[0144]

[0145]

[0146]

[0147]

[0148]

[0149]

[0150]

[0151]

[0152] As above, the UE can be configured with TCI-State configuration lists through higher layer parameters (e.g., PDSCH-Config). The UE can decode the PDSCH using the TCI-State configuration lists. Each TCI state can include parameters that configure the QCL relationship between one or two downlink reference signals and the DM-RS port of the PDSCH, the DM-RS port of the PDCCH, or the CSI-RS port(s) of the CSI-RS resource. The QCL can be configured for the first DL RS using the higher layer parameter qcl-Type1, and for the second DL RS using qcl-Type2. The QCL types of the two DL RSs can be configured differently regardless of whether they are DL RSs with the same reference or different DL RSs. The QCL type corresponding to each DL RS can be configured by the higher layer parameter (e.g., qcl-Type in QCL-Info). The QCL type can have one of the following values:

[0153] - typeA: {Doppler shift, Doppler spread, average delay, delay spread}

[0154] - typeB: {Doppler shift, Doppler spread}

[0155] - typeC: {Doppler shift, average delay}

[0156] - typeD: {Spatial Rx parameter}

[0157] Here, the Spatial RX parameter can refer to any one of various parameters, such as Angle of arrival (AoA), Power Angular Spectrum (PAS) of AoA, Angle of departure (AoD), PAS of AoD, transmit / receive channel correlation, transmit / receive beamforming, and spatial channel correlation.

[0158] The base station can transmit configuration information regarding whether to apply information in the transmission configuration indication (TCI) field included in the downlink control information (DCI) to the terminal through upper layer signaling.

[0159] Additionally, the terminal may receive information regarding TCI states or TCI state pairs. For example, the base station may transmit multiple TCI states to the terminal via RRC signaling, and may set some of them as TCI states for CORESET. The terminal may receive an activation command. The activation command may be used to map TCI state(s) and / or TCI state pair(s) to codepoints in the DCI field 'transmission configuration indication'.

[0160] Additionally, as shown in FIG. 10 below, it can be set to set a beam by integrating multiple channels or reference signals through a unified TCI state.

[0161] Instead of transmitting the TCI state for each channel to the UE, the base station can transmit information about beam settings for CSI-RS, CORESET, PDSCH, PUSCH, PUCCH, SRS, etc. to the UE through the unified TCI state. Whether the unified TCI state is activated or not can be explicitly or implicitly transmitted to the UE. For example, if the BWP of the CC does not have a TCI-State or TCI-UL-State configuration, the UE can apply the TCI-State or TCI-UL-State configuration from the reference BWP of the reference CC configured by the unified TCI-StateRef.

[0162] A multiple transmission and reception point (M-TRP) technique can be proposed, in which communication is performed through multiple transmitting and receiving nodes. The M-TRP technique can be divided into a single control information technique (single downlink control information (S-DCI)) that controls transmission and reception through multiple nodes through a single control information, and a multiple downlink control information technique (multiple downlink control information (M-DCI)) that separately transmits information for each node. In addition, the procedure for transmitting TCI information may vary depending on whether TCI information for uplink and downlink is set separately or jointly.

[0163] FIG. 11 illustrates an example of a setup procedure of each layer for transmitting a TCI state in an M-TRP structure according to one embodiment of the present disclosure.

[0164] First, there are two types of configurations related to TCI: separate and joint. In the separate type, the TCI state is set through separate TCI state lists for uplink and downlink, respectively, while in the joint type, the TCI state is set through joint TCI state lists for uplink and downlink. The base station can convey the configuration type related to the unified TCI to the terminal through unifiedTCI-StateType in ServingCellConfig. In addition, the base station can convey information about the resource set for the reference signal to the terminal through PDSCH-Config, and PDSCH-Config can be included in the BWP-Downlink IE.

[0165] Additionally, the terminal can be configured with a list of up to 128 TCI state configurations via upper layer parameters (e.g., dl-OrJointTCI-StateList in PDSCH-Config). The TCI configuration list can be used to provide criteria for determining ULTX spatial filters for dynamic-grant and configured-grant based PUSCH and PUCCH resources and SRS in BWP / CC.

[0166] Among the TCI state settings, the TCI state settings that are activated can be transmitted through the TCI state enable / disable MAC CE. The integrated TCI state enable / disable MAC CE can be defined as follows.

[0167]

[0168]

[0169] The integrated TCI state enable / disable MAC CE can indicate the TCI state ID to be enabled. The integrated TCI state enable / disable MAC CE includes a serving cell ID, a DL BWP ID, and an UL BWP ID. It can indicate a serving cell and a BWP to which the MAC CE can be applied as a code point. The Pi field can indicate whether each ith code point includes multiple TCI states or a single TCI state. If Pi = 1, the ith TCI code point includes multiple TCI states, and if Pi = 0, the ith TCI code point can include only a DL / joint TCI state or only a UL TCI state.

[0170] The D / U field can indicate whether the TCI state corresponding to the TCI state ID existing in the same octet is a DL / joint TCI state or an UL TCI state. Therefore, in FIG. 11, the D / U field belonging to the same octet as a separate type of DL TCI state and a joint type of TCI state can be set to 1, and the D / U field belonging to the same octet as a separate type of UL TCI state can be set to 0.

[0171] An enhanced integrated TCI state enable / disable MAC CE for joint TCI states can be defined as follows.

[0172]

[0173]

[0174] Unlike the integrated TCI state enable / disable MAC CE, the enhanced integrated TCI state enable / disable MAC CE for joint TCI states can jointly manage the TCI states of uplink and downlink, so the UL BWP ID can be omitted. The Fi,j field indicates whether the jth joint TCI state exists in the TCI state ID field associated with code point i of the DCI Transmission Configuration Indication field. Here, j can have the value 1 or 2. Therefore, in the case of the joint type as in step#2 of FIG. 11, up to two joint TCI states can correspond to each code point, and up to 16 joint TCI states can be activated.

[0175] An enhanced unified TCI state enable / disable MAC CE for separate TCI states can be defined as follows.

[0176]

[0177]

[0178] Unlike the unified TCI state enable / disable MAC CE, the enhanced unified TCI state enable / disable MAC CE for separate TCI states may include an Fi,j field and a Si,j field. The Fi,j field indicates whether the jth DL TCI state exists in the TCI state ID field associated with the code point i of the DCI Transmission Configuration Indication field. The Si,j field indicates whether the jth UL TCI state exists in the TCI state ID field associated with the code point i of the DCI Transmission Configuration Indication field. Therefore, in the case of the separate type of step#2 of FIG. 11, since each code point can correspond to at most two DL TCI states and at most two UL TCI states, a maximum of 32 TCI states can be enabled.

[0179] A base station can transmit DCI to a terminal via a PDCCH. The DCI can include a transmission configuration indication field, and decoding can be performed using the TCI state corresponding to the code point i in the transmission configuration indication field included in the DCI. As described above, the correspondence between the code point i and the TCI state can be indicated by a TCI state activation command.

[0180] The terminal can use the TCI state as follows using the received DCI.

[0181]

[0182]

[0183] That is, when the terminal receives a single TCI state for a CORESET, or receives a MAC CE activation command for one or two of the TCI states provided for the CORSET, the terminal may assume that the DM-RS antenna ports associated with the PDCCH receptions within the CORESET are in a QCL relationship with one or more DL RSs established by the TCI states.

[0184] A TCI state can be indicated by splitting it into two states. For example, if the terminal is provided with dl-OrJointTCI-StateList, the TCI states can be indicated through a combination of two TCI states (the first TCI state, the second TCI state, the first TCI state and the second TCI state, none). For example, if the terminal indicates the first TCI state through apply-IndicatedTCISate, the terminal can assume that the reference signal provided by the first TCI state and the DM-RS antenna port for PDCCH reception are in a QCL relationship.

[0185] If dl-OrJointTCI-StateList is provided to the UE and coresetPoolIndex is not provided to the UE or coresetPoolIndex is provided with 0 for the first coreset in the active DL BWP of the serving cell, the UE may assume that the DM-RS antenna ports for PDCCH reception in the first and second coresets and the DM-RS antenna ports for PDSCH reception scheduled by the DCI formats provided by PDCCH reception in the first and second coresets are in a QCL relationship with the reference signals provided by the TCI states specific to the first and second CORESETs, respectively. Furthermore, the UE may transmit the PUSCH scheduled by the DCI formats provided by PDCCH reception in the first and second CORESETs, respectively, using the spatial domain filters corresponding to the TCI states specific to the first and second CORESETs, respectively.

[0186] The TCI state can be used to transmit uplink signals. The terminal can use the following procedures to control uplink power.

[0187]

[0188]

[0189] Uplink power control can be used to determine power for PUSCH, PUCCH, SRS, or PRACH transmissions. The UE may be configured not to maintain more than four path loss estimates simultaneously for PUSCH / PUCCH / SRS transmissions per serving cell.

[0190] For PUSCH, PUCCH, SRS, or PRACH transmissions, a transmission opportunity can be defined by a slot index within a frame, the first symbol within the slot, and the number of consecutive symbols. If the UE receives TCI states in dl-OrJointTCI-StateList, an RS index for downlink path loss estimation for PUSCH, PUCCH, or SRS transmission can be provided for each one or both TCI states for PUSCH, PUCCH, or SRS transmission opportunities.

[0191] Power control values ​​can be set explicitly or implicitly. For example, if followUnifiedTCI-StateSRS is set, power control values ​​are provided from p0AlphaSetforSRS associated with the TCI state. If followUnifiedTCI-StateSRS is not set, power control values ​​and an RS index for path loss estimation can be provided from the TCI state associated with the SRS resource with the lowest SRS-ResourceId. In this case, the overall SRS power value can be determined based on the sum of individual SRS power control values ​​and additional components according to the SRS resource set.

[0192] Hereinafter, the initial connection procedure between a terminal and a base station will be described. If the initial connection procedure is performed with the base station due to reasons such as the terminal's power on / off operation or loss of coverage, an identification procedure between the base station and the terminal may be required. First, the terminal may perform an initial cell search operation with the base station. The terminal may perform monitoring to receive a synchronization signal. The synchronization signal may be at least one of a primary synchronization signal (PSS) and a secondary synchronization signal (SSS). The terminal may receive a physical broadcast channel (PBCH) signal from the base station to obtain broadcast information within the cell. Based on the physical broadcast channel, the terminal may obtain information about the cell using at least one of the MIB or SIB. A block including all of the PSS, SSS, and PBCH may be referred to as a synchronization signal block (SSB).

[0193] A terminal can perform a random access procedure. The terminal can transmit a preamble to the base station and receive a random access response (RAR) from the base station. The RAR message can include a temporary identifier. The terminal can transmit MSG3 (or an RRC connection request message) using the scheduling information in the RAR, and the base station can perform a contention resolution procedure by transmitting MSG4 (or a contention resolution message) to the terminal in response to MSG3.

[0194] The base station can perform beam management based on the RACH opportunity used for preamble transmission in the random access procedure. For example, the base station can determine the beam on which the terminal received the synchronization signal based on the RACH opportunity in which the preamble was transmitted. As described above, a synchronization signal can also be included as a reference signal for indicating the QCL relationship, and the QCL relationship can be established based on the SSB received through the initial access procedure.

[0195] Additionally, a channel measurement procedure may be performed for beam management. The terminal may receive a reference signal from the base station. Based on this, the terminal may report channel state information (CSI) to the base station. The channel state information may include at least one of reference signal received power (RSRP), reference signal received quality (RSRQ), and signal-to-noise ratio (SNR). The base station may use the received channel state information to adjust beamforming for the terminal or optimize radio resource allocation. For channel measurement, the base station may transmit configuration information for channel measurement to the terminal. The configuration information for channel measurement may include information related to a measurement target, a measurement cycle, and the like.

[0196] Base station and terminal beam settings can be managed through artificial intelligence (AI). For convenience, beam set B refers to the beam set where measurements are performed using AI / ML model input, and beam set A refers to the beam set determined based on AI / ML model inference. Beam sets A and B may contain beam information for the same frequency range.

[0197] Artificial intelligence can be used to infer spatial domain downlink beams for beam set A based on measurements of beam set B. As another example, artificial intelligence can be used to infer temporal downlink beams for beam set A based on past measurements of beam set B. Here, beam set A and beam set B may be different sets, or beam set B may be a subset of beam set A.

[0198] Additionally, the input of the artificial intelligence model can be formed from various combinations. For example, the input of the artificial intelligence can include at least one of an L1-RSRP measurement based on beam set B, other auxiliary information, a channel impulse response (CIR) based on beam set B, and a downlink Tx / Rx beam ID associated with the L1-RSRP measurement of beam set B.

[0199] The aforementioned artificial intelligence model can be designed to infer a beam including at least one of a downlink reception beam and a downlink transmission beam. In addition, the output of the artificial intelligence model can include at least one of a transmission beam, a reception beam, an L1-RSRP of the transmission beam, an L1-RSRP of the reception beam, an angle of the transmission beam, an angle of the reception beam, and other information.

[0200] The beam management method using an AI model is not limited to the aforementioned method. The AI ​​model can be configured in various ways by configuring inputs and outputs with various combinations of settings for beam sets A and B, performance monitoring, data collection, and auxiliary information.

[0201] Learning and inference methods can also be implemented in various ways. For example, artificial intelligence can be learned or trained using an AI / ML (artificial intelligence / machine learning) model. Learning and training can be performed by the network or the UE. Furthermore, learning and inference can be performed on different devices. For example, learning can be performed on the network and inference on the UE. Split learning can be performed in such a way that some of the learning is performed on a first device and some on a second device. Similarly to learning, split inference can be performed using multiple devices. Input data for inference can also be generated in various ways. For example, input data can be generated on the UE, and inference can be performed using the input data on the network. Furthermore, input data generated on the UE can be used for inference within the UE.

[0202] The present disclosure proposes a radio link monitoring-based UI / ED (UE-initiated / Event-driven) beam reporting technique to reduce signaling overhead and delay for beam reporting. The present disclosure proposes a technique that utilizes a unified transmission configuration indicator (TCI) and leverages existing CSI measurement and reporting (configuration) frameworks. The present disclosure proposes a technique for performing intra-cell and inter-cell beam management in FR2 and single transmission / reception point (sTRP) environments.

[0203] Using the technology proposed in this disclosure, fast beam switching can be performed according to the UL signal content and procedure for UI / ED beam reporting. In addition, according to this disclosure, a UL signaling medium / container can be designed considering the UI / ED characteristics of UL transmission, and beam reporting can be performed. Using the technology of this disclosure, signaling overhead and delay for beam reporting based on radio link monitoring can be reduced while maintaining the existing beam measurement and reporting method as much as possible.

[0204] - CSI-ReportConfigThe IECSI-ReportConfigis used to configure a periodic or semi-persistent report sent on PUCCH on the cell in which theCSI-ReportConfigis included, or to configure a semi-persistent or aperiodic report sent on PUSCH triggered by DCI received on the cell in which theCSI-ReportConfigis included (in this case, the cell on which the report is sent is determined by the received DCI). See TS 38.214

[0019] , clause 5.2.1.CSI-ReportConfiginformation element-- ASN1START-- TAG-CSI-REPORTCONFIG-STARTCSI-ReportConfig ::= SEQUENCEreportConfigId CSI-ReportConfigId,carrier ServCellIndex OPTIONAL, -- Need SresourcesForChannelMeasurement CSI-ResourceConfigId,csi-IM-ResourcesForInterference CSI-ResourceConfigId OPTIONAL, -- Need Rnzp-CSI-RS-ResourcesForInterference CSI-ResourceConfigId OPTIONAL, -- Need RreportConfigType CHOICEperiodic SEQUENCEreportSlotConfig CSI-ReportPeriodicityAndOffset,pucch-CSI-ResourceList SEQUENCE (SIZE (1..maxNrofBWPs)) OF PUCCH-CSI-Resource,semiPersistentOnPUCCH SEQUENCEreportSlotConfig CSI-ReportPeriodicityAndOffset,pucch-CSI-ResourceList SEQUENCE (SIZE (1..maxNrofBWPs)) OF PUCCH-CSI-Resource,semiPersistentOnPUSCH SEQUENCEreportSlotConfig ENUMERATED sl5, sl10, sl20, sl40, sl80, sl160, sl320,reportSlotOffsetList SEQUENCE (SIZE (1.. maxNrofUL-Allocations)) OF INTEGER(0..32),p0alpha P0-PUSCH-AlphaSetId,aperiodic SEQUENCEreportSlotOffsetList SEQUENCE (SIZE (1..maxNrofUL-Allocations)) OF INTEGER(0..32),reportQuantity CHOICEnone NULL,cri-RI-PMI-CQI NULL,cri-RI-i1 NULL,cri-RI-i1-CQI SEQUENCEpdsch-BundleSizeForCSI ENUMERATED n2, n4 OPTIONAL -- Need S,cri-RI-CQI NULL,cri-RSRP NULL,ssb-Index-RSRP NULL,cri-RI-LI-PMI-CQI NULL,reportFreqConfiguration SEQUENCEcqi-FormatIndicator ENUMERATED widebandCQI, subbandCQI OPTIONAL, -- Need Rpmi-FormatIndicator ENUMERATED widebandPMI, subbandPMI OPTIONAL, -- Need Rcsi-ReportingBand CHOICE.

[0205] [Table 8] shows CSI-ReportConfig, which is part of the configuration information for CSI reporting provided to the terminal from the TRP, gNB, or NW (network) through RRC configuration. Through CSI-ReportConfig, the CSI reporting method, the configuration of the UL physical channel used as the container, and the report quantity can be configured. Here, the CSI reporting method can be configured as one of periodic, semi-persistent, or aperiodic.

[0206] BFR-related RRC configurations, including configurations related to BFD (beam failure detection)-RS, can be configured via RadioLinkMonitoringConfig as shown in [Table 9] below. [Table 9] below shows configuration information regarding radio link monitoring provided to the UE via RRC signaling.

[0207] failureDetectionResourcesToReleaseList SEQUENCE (SIZE(1..maxNrofFailureDetectionResources)) OF RadioLinkMonitoringRS-IdOPTIONAL, -- Need NbeamFailureInstanceMaxCount ENUMERATED n1, n2, n3, n4, n5, n6, n8, n10 OPTIONAL, -- Need RbeamFailureDetectionTimer ENUMERATED pbfd1, pbfd2, pbfd3, pbfd4, pbfd5, pbfd6, pbfd8, pbfd10 OPTIONAL, -- Need R...,[[beamFailure-r17 BeamFailureDetection-r17 OPTIONAL -- Need R]]BeamFailureDetection-r17 ::= SEQUENCEfailureDetectionSet1-r17 BeamFailureDetectionSet-r17 OPTIONAL, -- Need RfailureDetectionSet2-r17 BeamFailureDetectionSet-r17 OPTIONAL, -- Need RadditionalPCI-r17 AdditionalPCIIndex-r17 OPTIONAL -- Need RRadioLinkMonitoringRS ::= SEQUENCEradioLinkMonitoringRS-Id RadioLinkMonitoringRS-Id,purpose ENUMERATED beamFailure, rlf, both,detectionResource CHOICEssb-Index SSB-Index,csi-RS-Index NZP-CSI-RS-ResourceId,...

[0208] During the operation of BFR, the UE measures the L1-RSRP for the beam in use through BFD-RS, and detects beam failure when the corresponding L1-RSRP value is less than or equal to a configured value. Thereafter, the UE searches for a new candidate beam. When the number of beam failures detected exceeds the configured value, BFR is triggered, and accordingly, the UE transmits a beam recovery request to the gNB or NW (network) through a random access procedure. The gNB or NW can transmit a response to the beam recovery request to the UE. In order to prevent frequent BFR (beam failure recovery) related operations in NR and to perform efficient UI / ED beam reporting, the present disclosure proposes a BFR-based UI / ED beam reporting scheme.

[0209] According to one embodiment, the BFR procedure may be performed through the following operations.

[0210] 1) Beam Failure Detection: The UE measures the BFD-RSs configured through the RRC configuration. The UE measures the L1-RSRP for the beam currently being used by the UE, and determines that a beam failure has occurred if the L1-RSRP falls below a specific value. Here, a specific value for the L1-RSRP can be set through RRC signaling. For example, the BFD-RS may include a CSI-RS or SSB.

[0211] 2) Search for candidate beam: To perform the BFR procedure, the UE searches for candidate beams based on beam measurements for BFD-RS.

[0212] 3) BFR Triggering: BFR is triggered when the number of beam failure(s) detected exceeds a certain value. For example, BFR is triggered when the number of beam failure detection(s) exceeds the value of the beamFailureInstanceMaxCount parameter configured by RRC.

[0213] 4) BFR Execution: The UE performs BFR by sending a BFR request through a random access procedure and receiving a corresponding response. For the BFR request, the UE transmits a sequence or preamble configured through a candidate beam index and a mapped random access occasion.

[0214]

[0215] The present disclosure below describes various embodiments for performing beam management using UI / ED beam reporting prior to BFR operation occurrence, thereby preventing BFR from occurring.

[0216]

[0217] FIG. 12 illustrates a first embodiment of performing beam reporting based on BFD-RS according to an embodiment of the present disclosure. Referring to FIG. 12 , UI / ED beam reporting may be performed in response to a BFD-RS-based beam failure detection. In the following description, a base station may be understood as a gNB, a NW, or a TRP.

[0218] Referring to FIG. 12, in step S1201, the UE receives an RRC configuration message. The UE can receive a configuration message required for UI / ED beam reporting through the RRC configuration. Here, the RRC configuration message may include one message or multiple messages, and may include at least one of the following items.

[0219] - Configuration of UL physical channels (e.g., PUCCH, PUSCH, etc.) for transmitting UI / ED beam report information: This may include configuration information for time and frequency resources for which PUCCH and PUSCH are configured, the period of PUCCH and PUSCH if configured, the corresponding period, offset value, etc.

[0220] - Configuration of the type of information to be transmitted through beam reporting: reportQuantity can be set to SSBRI (ss / pbch block resource indicator), CRI (CSI reference signal resource indicator), (L1-)RSRP (reference signal received power), SINR (signal-to-interference-plus-noise ratio), CQI (channel quality indicator), RI (rank indicator), PMI (precoding matrix indicator), LI (layer indicator), or a combination thereof. Hereinafter, reportQuantity is referred to as 'beam state information (BSI)'.

[0221] - Configuration for event for UI / ED beam reporting triggering: This refers to an event that triggers UI / ED beam reporting. The event may be predefined or configured via an RRC message. At least one event may be configured via an RRC message. The UE may determine a UI / ED beam reporting operation based on at least one event. For example, a specific event may mean that the L1-RSRP measured for the corresponding beam is greater than or equal to a specific value. Here, the specific event may be configured for the purpose of searching for a beam that is guaranteed to have a quality level greater than or equal to a certain level. In addition, the beam report may be configured to include information related to the best beam among the currently measurable beams (e.g., the beam with the highest measured RSRP value). This configuration information may be signaled via RRC.

[0222] - Candidate beam search condition for UI / ED beam reporting: This is configuration information for searching for a beam that satisfies a specific condition and performing UI / ED beam reporting only if the beam exists. For example, the specific condition may include that the measured channel quality (e.g., L1-RSRP) for the beam is greater than or equal to a specific value. In other words, the candidate beam may mean a beam that provides a channel quality greater than or equal to a specific threshold. Alternatively, the candidate beam may be the best beam among the currently measurable beams. The specific condition can be configured in various forms, for example, the specific condition may be configured via RRC.

[0223] In step S1203, the base station transmits a BFD-RS, and the UE receives the BFD-RS. Accordingly, the UE can perform measurements on the BFD-RS based on the RRC configuration information.

[0224] At step S1205, the UE detects a beam failure. Then, a UI / ED beam report is triggered. If a UI / ED beam report is triggered, a procedure for beam reporting is performed.

[0225] In step S1207, the UE performs a UI / ED beam search. The UE can determine a candidate beam that satisfies a specific condition among the beams measured based on BFD-RS. The specific condition can be determined based on the RRC configuration related to the UI / ED beam report.

[0226] In step S1209, the UE transmits a UI / ED beam report. If there is a beam satisfying a specific condition, the UE performs a UI / ED beam report. If there is no beam satisfying the specific condition among the candidate beams, the UI / ED beam report may not be performed. The UI / ED beam report may be transmitted through a PUCCH or PUSCH determined based on an RRC configuration related to the UI / ED beam report. At this time, information about the beam included in the UI / ED beam report may be determined based on a reportQuantity configured by the RRC. For example, the information about the beam may include SSBRI, L1-RSRP, CRI, and L1-RSRP, SSBRI, SINR, CRI, SINR, or a combination thereof.

[0227] In the embodiment of FIG. 12, the threshold of the channel quality (e.g., L1-RSRP) for UI / ED beam reporting can be set to a different value (e.g., a relatively higher value or a lower value) than the threshold used for beam failure detection. For example, the condition for UI / ED beam reporting triggering can be set to a case where the configured BFD-RS is lower than a specific threshold. Here, the specific threshold can be set differently from the threshold used for beam failure detection determination, and can be configured via RRC for UI / ED beam reporting triggering. Therefore, in FIG. 12, the condition for UI / ED beam reporting triggering can be set to a different condition from the triggering by beam failure detection, and can be determined through quality measurement for the currently used beam via BFD-RS.

[0228]

[0229] FIG. 13 illustrates a second embodiment of performing beam reporting based on BFD-RS according to an embodiment of the present disclosure. Referring to FIG. 13 , UI / ED beam reporting may be triggered when the number of BFD-RS-based beam failure detections exceeds a specific threshold. In the following description, a base station may be understood as a gNB, a NW, or a TRP.

[0230] Referring to FIG. 13, in step S1301, the UE receives an RRC configuration message. The UE can receive a configuration message required for UI / ED beam reporting through the RRC configuration. Here, the RRC configuration message can include a maximum number of beam failure instances, which is a parameter related to the BFR procedure. Here, the maximum number of beam failure instances can be understood as the maximum number of beam failures allowed. The maximum number of beam failure instances can be indicated using beamFailureInstanceMaxCount configured through RRC.

[0231] In steps S1303-1 to S1303-k, the base station transmits BFD-RSs, and the UE receives the BFD-RSs. Accordingly, the UE can perform measurements on the BFD-RSs based on RRC configuration information.

[0232] At step S1305, the UE detects a beam failure. Accordingly, a UI / ED beam report is triggered. For example, the UI / ED beam report may be triggered when the BFD-RS-based beam failure detection is greater than a certain threshold (e.g., X in FIG. 13). Here, the certain threshold may be set to a value smaller than the maximum number of beam failure instances.

[0233] In step S1307, the UE performs a UI / ED beam search. The UE may search for candidate beams that satisfy specific conditions among beams measured based on BFD-RS. The specific conditions may be determined based on the RRC configuration related to the UI / ED beam report.

[0234] In step S1309, the UE transmits a UI / ED beam report. If there is a beam satisfying a specific condition, the UE performs a UI / ED beam report. If there is no beam satisfying the specific condition among the candidate beams, the UI / ED beam report may not be performed. The UI / ED beam report may be transmitted through a PUCCH or PUSCH determined based on an RRC configuration related to the UI / ED beam report. At this time, information about the beam included in the UI / ED beam report may be determined based on a reportQuantity configured by the RRC. For example, the information about the beam may include SSBRI, L1-RSRP, CRI, and L1-RSRP, SSBRI, SINR, CRI, SINR, or a combination thereof.

[0235] In the embodiment of FIG. 13, the threshold of the channel quality (e.g., L1-RSRP) for UI / ED beam reporting can be set to a different value (e.g., a relatively higher value or a lower value) than the threshold used for beam failure detection. For example, the condition for triggering UI / ED beam reporting can be configured as a case where the number of cases where BFD-RS is lower than the specific threshold occurs more than a specific threshold, rather than a case where the number of BFD-RS-based beam failure detections is greater than a specific threshold. Here, the specific threshold can be set differently from the threshold used for beam failure detection determination, and can be configured via RRC for triggering UI / ED beam reporting.

[0236] Also in FIG. 13, a counter may be used to record the number of beam failures or the number of times the measured value on the currently used beam is less than the set L1-RSRP value. Here, the counter may be reset when a certain threshold is exceeded, triggering a UI / ED beam report. In this case, the counter may be restarted from the beginning, and a UI / ED beam report may be triggered again when the value stored in the counter exceeds the threshold.

[0237]

[0238] As described above, UI / ED beam reporting can be used for BFR procedures. Furthermore, according to various embodiments, UI / ED beam reporting for BFR procedures can be performed based on contention-free based random access (CFRA). Hereinafter, the present disclosure describes embodiments in which UI / ED beam reporting is performed using contention-free based random access (CFRA) with reference to FIGS. 14 and 15.

[0239]

[0240] FIG. 14 illustrates a third embodiment of performing beam reporting based on BFD-RS according to an embodiment of the present disclosure. Referring to FIG. 14 , UI / ED beam reporting is triggered whenever a BFD-RS-based beam failure is detected and can be performed using CFRA. In the following description, a base station may be understood as a gNB, a NW, or a TRP.

[0241] Referring to FIG. 14, in step S1401, the UE receives an RRC configuration message. The UE may receive a configuration message required for UI / ED beam reporting through the RRC configuration. Here, the RRC configuration message may include information related to BFR and information related to UI / ED beam reporting. Here, the information related to UI / ED beam reporting may include a dedicated preamble or sequence information for performing UI / ED beam reporting through CFRA through RRC configurations. The configured dedicated preamble or sequence may be configured and assigned to the UE separately from the BFR request.

[0242] In step S1403, the base station transmits a BFD-RS, and the UE receives the BFD-RS. Accordingly, the UE can perform measurements on the BFD-RS based on the RRC configuration information.

[0243] At step S1405, the UE detects a beam failure. Accordingly, a UI / ED beam report is triggered. The UI / ED beam report may be triggered in response to the detection of a BFD-RS-based beam failure.

[0244] In step S1407, the UE performs UI / ED beam search. The UE may search for a candidate beam that satisfies a specific condition among beams measured based on BFD-RS. The specific condition may be determined based on an RRC configuration related to UI / ED beam reporting. If there is a beam that satisfies the specific condition, the UE performs UI / ED beam reporting through the CFRA procedure. If there is no candidate beam that satisfies the specific condition, UI / ED beam reporting may not be performed. That is, if there is no candidate beam that satisfies the specific condition, CFRA may not be performed. CFRA may be performed through a 2-step random access procedure.

[0245] In step S1409, the UE transmits MsgA, which may be used for UI / ED beam reporting. The transmission of MsgA may include a PUSCH transmission including a preamble transmission. The PUSCH is transmitted in a resource region mapped by a random access opportunity and a preamble index. Accordingly, index information for the beam, such as SSBRI or CRI, may be reported through the preamble transmission. Quality values ​​for the beam, such as L1-RSRP or SINR values, may be transmitted through the PUSCH.

[0246] At step S1411, the UE receives MsgB. The UE can complete the CFRA procedure by receiving MsgB. Here, MsgB may include information indicating whether to change to the beam reported via MsgA.

[0247] In the embodiment of FIG. 14, the channel quality (e.g., L1-RSRP) threshold for UI / ED beam reporting can be set to a different value (e.g., a relatively higher value or a lower value) than the threshold used for beam failure detection. For example, the condition for UI / ED beam reporting triggering can be configured when a case occurs where the configured BFD-RS is lower than a specific threshold. Here, the specific threshold can be set differently from the threshold used for beam failure detection determination, and can be configured via RRC for UI / ED beam reporting triggering. Therefore, in FIG. 14, the condition for UI / ED beam reporting triggering can be configured to a different condition from the triggering by beam failure detection, and can be determined through quality measurement for the currently used beam via BFD-RS.

[0248]

[0249] FIG. 15 illustrates a fourth embodiment of performing beam reporting based on BFD-RS according to an embodiment of the present disclosure. Referring to FIG. 15 , UI / ED beam reporting is triggered when the number of beam failure detections based on BFD-RS exceeds a specific threshold, and may be performed using CFRA. In the following description, a base station may be understood as a gNB, a NW, or a TRP.

[0250] Referring to FIG. 15, in step S1501, the UE receives an RRC configuration message. The UE can receive a configuration message required for UI / ED beam reporting through the RRC configuration. Here, the RRC configuration message can include a maximum number of beam failure instances, which is a parameter related to the BFR procedure. Here, the maximum number of beam failure instances can be understood as the maximum number of beam failures allowed. The maximum number of beam failure instances can be indicated using beamFailureInstanceMaxCount configured through RRC.

[0251] In steps S1503-1 to S1503-k, the base station transmits BFD-RSs, and the UE receives the BFD-RSs. Accordingly, the UE can perform measurements on the BFD-RSs based on RRC configuration information.

[0252] At step S1505, the UE detects a beam failure. Accordingly, a UI / ED beam report is triggered. The UI / ED beam report may be triggered when the BFD-RS-based beam failure detection is greater than a certain threshold (e.g., X in FIG. 15). Here, the certain threshold may be configured to be a value less than the maximum number of beam failure instances.

[0253] In step S1507, the UE performs UI / ED beam search. The UE may search for candidate beams that satisfy specific conditions among beams measured based on BFD-RS. The specific conditions may be determined based on an RRC configuration related to UI / ED beam reporting. If there is a beam that satisfies the specific conditions, the UE performs UI / ED beam reporting through the CFRA procedure. If there is no candidate beam that satisfies the specific conditions, the UI / ED beam reporting is not performed. In other words, if there is no candidate beam that satisfies the specific conditions, CFRA may not be performed. CFRA may be performed through a 2-step random access procedure.

[0254] In step S1509, the UE transmits MsgA, which may be used for UI / ED beam reporting. The transmission of MsgA may include a PUSCH transmission including a preamble transmission. The PUSCH is transmitted in a resource region mapped by a random access opportunity and a preamble index. Therefore, index information for the beam, such as SSBRI or CRI, may be reported through the preamble transmission. Quality values ​​for the beam, such as L1-RSRP or SINR values, may be transmitted through the PUSCH.

[0255] In step S1511, the UE receives MsgB. Upon receiving MsgB, the UE can complete the CFRA procedure. MsgB may include information indicating whether to change to the beam reported in MsgA.

[0256] In the embodiment of FIG. 15, the threshold of channel quality (e.g., L1-RSRP) for UI / ED beam reporting can be configured to be a different value (e.g., a relatively higher value or a lower value) than the threshold used for beam failure detection. For example, the condition for UI / ED beam reporting triggering can be configured to be a case where BFD-RS is lower than a specific threshold more than a specific threshold, rather than a case where BFD-RS-based beam failure detection is greater than a specific threshold. Here, the specific threshold can be different from the threshold used for beam failure detection determination, and can be configured via RRC for UI / ED beam reporting triggering.

[0257] Also in FIG. 15, a counter may be used to record the number of beam failures or the number of times the measured value on the currently used beam is less than a threshold (e.g., a configured L1-RSRP value). Here, the counter may be reset when a certain threshold is exceeded, triggering a UI / ED beam report. In this case, the counter may start recording the count again from the beginning. The UI / ED beam report may be triggered again when the value stored in the counter exceeds the threshold.

[0258]

[0259] In order to perform the procedures described with reference to FIGS. 12 to 15, within the RadioLinkMonitoringConfig IE (information element), the purpose of RadioLinkMonitoringRS may additionally include beam reporting in addition to the existing beamFailure, rlf, and both. In this case, the RRC configuration may be configured and operated for the purpose of UI / ED beam reporting. In addition, the configuration information included in the RRC configuration may be configured and operated for the purpose of UI / ED beam reporting.

[0260]

[0261] FIG. 16 illustrates an example of a procedure in which a terminal detects a beam failure and performs a UI / ED beam report according to one embodiment of the present disclosure.

[0262] Referring to Figure 16, at step S1601, the terminal establishes a connection with the base station. To establish a connection with the base station, the terminal may perform a random access procedure for initial access. For example, the terminal may receive a synchronization signal and system information from the base station, transmit a RACH preamble, receive a random access response (RAR) message, and perform procedures for establishing an RRC connection.

[0263] In step S1603, the terminal receives at least one RRC configuration message from the base station. The RRC configuration message may include at least one of information related to NW-initiated beam reporting (e.g., configuration information for CSI reporting) or information related to UI / ED beam reporting. For example, the RRC configuration message may include at least one of information about a reference signal, information about a physical channel configuration through which the beam report message is transmitted, information about searching for a candidate beam to be indicated through the beam report, or information about a quantity related to the beam report. Here, the reference signal, physical channel, and quantity related to the UI / ED beam report may be configured independently from the reference signal, physical channel, and quantity related to the NW-initiated beam report.

[0264] In step S1605, the terminal receives at least one reference signal from the base station. The terminal may receive the at least one reference signal based on information included in a previously received RRC configuration message. According to an embodiment, the at least one reference signal may include at least one reference signal allocated or configured for beam failure detection. The terminal may determine information related to a beam state currently being used by the terminal for wireless communication based on the received at least one reference signal. Here, the information related to the beam state may include at least one of SSBRI, CRI, (L1-)RSRP, SINR, CQI, RI, PMI, and LI.

[0265] In step S1607, the terminal detects a beam failure based on at least one reference signal. The terminal may measure the quality (e.g., RSRP) of at least one reference signal. If the measured quality is below a certain threshold, the terminal may consider the currently used beam to have failed.

[0266] In step S1609, the terminal determines triggering for a beam report based on at least one reference signal. Triggering for a beam report may be determined when a specific condition is met. Here, the specific condition may be preset or configured by the base station. If configured by the base station, information regarding a specific event may be conveyed via an RRC configuration message. For example, the specific condition may include the presence of a beam providing a channel quality higher than a predefined or configured threshold. Here, the threshold associated with the specific condition may be the same as or different from a threshold for beam failure detection.

[0267] In step S1613, the terminal transmits a beam report message to the base station. In response to a trigger for a beam report, the terminal may generate and transmit a beam report message. The beam report message may be transmitted via a physical channel configured by an RRC configuration message. According to one embodiment, the terminal may transmit the beam report message via a PUSCH or PUCCH. According to another embodiment, the terminal may transmit the beam report message via a RACH preamble and a corresponding PUSCH.

[0268]

[0269] FIG. 17 illustrates an example of a procedure for a base station to receive a UI / ED beam report according to one embodiment of the present disclosure.

[0270] Referring to Figure 17, at step S1701, the base station establishes a connection with the terminal. The base station may perform a random access procedure for initial connection to establish a connection with the terminal.

[0271] In step S1703, the base station transmits at least one RRC configuration message to the terminal. The RRC configuration message may include at least one of information related to NW-initiated beam reporting (e.g., configuration information for CSI reporting) and information related to UI / ED beam reporting. For example, the RRC configuration message may include at least one of information about the reference signal, information about a physical channel configuration through which the beam report message is transmitted, information about searching for a candidate beam to be indicated through the beam report, or information about a quantity related to the beam report. Here, the reference signal, physical channel, and quantity related to the UI / ED beam report may be configured independently from the reference signal, physical channel, and quantity related to the NW-initiated beam report.

[0272] In step S1705, the base station transmits at least one reference signal to the terminal. The base station may transmit at least one reference signal based on information included in a previously transmitted RRC configuration message. According to one embodiment, the at least one reference signal may include at least one reference signal allocated or configured for beam failure detection. The at least one reference signal may be used to determine information related to a beam state currently being used by the terminal for wireless communication. For example, the at least one reference signal may include SSB, CSI-RS, or technically equivalent signals thereof.

[0273] In step S1707, the base station receives a beam report message from the terminal. The beam report message may be received via a physical channel configured by an RRC configuration message. According to one embodiment, the terminal may transmit the beam report message via a PUSCH or PUCCH. According to another embodiment, the terminal may transmit the beam report message via a RACH preamble and its corresponding PUSCH.

[0274]

[0275] The UI / ED beam report transmission procedure can support the following Modes A and B. Mode A can be understood as a mode in which the gNB dynamically schedules UCI. In Mode A, the UE requests resources for performing beam reporting on the second uplink channel via the first PUCCH. The request format (e.g., SR or a new UCI type) may be further reviewed during this process. The UE then detects the DCI format to indicate the resources of the second UL channel on which the beam report will be transmitted. The beam report is transmitted via the second UL channel. This option is a basic function of the UE, and all UEs that support UI / ED beam reporting must provide this function. In addition, a new DCI format may not be introduced. Mode B can be understood as a mode in which UCI is used on the resources of the pre-configured second uplink channel. The UE transmits the first PUCCH to indicate that it will perform beam reporting on the second uplink channel. The notification format (e.g., SR or a new UCI type) may be further reviewed. The UE then transmits the beam report via the second uplink channel. At this time, the specific type of the second uplink channel (e.g., whether PUCCH, PUSCH, or both channels are used) may be further reviewed. Furthermore, the notification in Step 1 may be performed as a separate reporting instance from the beam reporting. Whether the UE receives response information may also be further reviewed. Cross-CC beam reporting may be supported for both options.

[0276] For Mode A, the first PUCCH channel supports a 1-bit indication and requests resources for the second UL channel to transmit beam reports. In this case, periodic PUCCH resources are configured via dedicated RRC signals, and PUCCH formats 0 or 1 are used. For Mode B, the first PUCCH channel supports a 1-bit indication and indicates that beam reports will be transmitted on the second UL channel. In this case, periodic PUCCH resources are configured via dedicated RRC signals, and PUCCH formats 0 or 1 are used. Whether and how to support multi-bit indications on the first PUCCH in Modes A and B when multiple events are approved may be further reviewed. The details of the dedicated RRC signals may also be further reviewed. The above applies at least to the single CC case.

[0277] For Mode A, the UL-Grant DCI format includes at least DCI formats 0_1 and 0_2, and the second channel may include a PUSCH. The terminal beam reporting trigger scheme through DCI format 0_3 and the UL-Grant DCI format may be further reviewed.

[0278] Additionally, when the DCI format is defined as a DL-Grant DCI format, the second channel can be set to PUCCH. A 1-bit field is included in the DL-Grant DCI format and can indicate transmission of a UEI (UE initiated) beam report. In this case, the PUCCH resource for HARQ-ACK transmission can be reused for transmitting both HARQ-ACK and UEI reports. The DL-Grant DCI format includes at least DCI formats 1_1 and 1_2, and whether DCI format 1_3 is included can be additionally reviewed.

[0279] In the transmission procedure for UI / ED beam reporting, one of the following two alternatives can be selected with respect to the dedicated RRC signal for the first PUCCH channel configuration of Mode A.

[0280] Alt-1: Configure a dedicated SR for Mode A

[0281] An RRC parameter (e.g., reportResourceRequest-UEIBR) corresponding to the 1-bit instruction of the first PUCCH channel is introduced. Here, the RRC parameter is associated with a dedicated SchedulingRequestId.

[0282] Alternative 2 (Alt-2): Create a new UCI type.

[0283] An RRC parameter (e.g., firstPUCCHResourceConfig-ModeA-UEIBR) is introduced for periodic PUCCH resource configuration. This RRC parameter is not associated with SchedulingRequestId. Further consideration may be given to encoding 1 bit into PUCCH resources (e.g., reusing the encoding mechanism for positive / negative SR). The dedicated RRC parameter may include periodicityAndOffset or PUCCH-ResourceID. The above applies at least to single-CC cases.

[0284] In the transmission procedure for UI / ED beam reporting, one of the following two alternatives can be selected with respect to the dedicated RRC signal for the first PUCCH channel configuration of Mode B.

[0285] Alternative 1 (Alt-1): Configure a dedicated SR for Mode B

[0286] An RRC parameter (e.g., reportNotification-UEIBR) corresponding to the 1-bit indication of the first PUCCH channel is introduced. This RRC parameter is associated with a dedicated SchedulingRequestId. The specific signaling method is determined by RAN2.

[0287] Alternative 2 (Alt-2) Create a new UCI type

[0288] An RRC parameter (e.g., firstPUCCHResourceConfig-ModeB-UEIBR) is introduced for periodic PUCCH resource configuration. This RRC parameter is not associated with SchedulingRequestId. Further consideration may be given to encoding 1 bit into PUCCH resources (e.g., reusing the encoding mechanism for positive / negative SR). Dedicated RRC parameters may include periodicityAndOffset or PUCCH-ResourceID. The above applies at least to single-CC cases.

[0289] In the transmission procedure for UI / ED beam reporting, the triggering procedure related to Mode A may be selected from one of the following two options.

[0290] Option 1: A new 1-bit field is introduced in DCI formats 0_1 / 0_2 to trigger UEI beam reporting transmission. Further consideration may be given to DCI format 0_3.

[0291] Option 2: Reuse the existing CSI request field of DCI format 0_1 / 0_2 to trigger terminal beam report transmission. Further consideration may be given to DCI format 0_3.

[0292] Handling of multiple CSI reporting configurations associated with the same first PUCCH resource or the same scheduled PUSCH related to UI / ED beam reporting may be further reviewed.

[0293] In the UI / ED based beam report transmission procedure, the UEI beam report associated with Mode B is transmitted at the first available transmission opportunity on the second uplink channel X symbols after the last symbol in which a report notification was transmitted on the first PUCCH channel.

[0294] In the UI / ED beam report transmission procedure, the following options may be provided for resource mapping / configuration between the first channel and the second channel for a specific CSI report configuration in Mode B.

[0295] Option 1: One-to-one

[0296] Only one first PUCCH resource and one pre-configured second uplink channel resource can be associated with a CSI reporting configuration for UI / ED beam reporting.

[0297]

[0298] Option 1A: The first PUCCH resource and the second uplink channel resource have the same periodicity.

[0299] Option 1B: No restrictions on periodicity.

[0300] Option 2: One-to-M

[0301] One first PUCCH resource and one or more pre-configured second uplink channel resources may be associated with a CSI reporting configuration for UI / ED beam reporting.

[0302] In the UI / ED beam report transmission procedure, the triggering procedure of Mode A can be defined as follows.

[0303] The CSI request field in DCI format 0_1 / 0_2 is reused to trigger UEI beam report transmission. If the CSI request field indicates a CSI trigger state associated with the UEI beam report configuration, the UE transmits the relevant UEI beam report on the second PUSCH scheduled by the corresponding DCI format 0_1 / 0_2. Further considerations regarding DCI format 0_3 may be made here.

[0304] The need to dedicate the CSI trigger state to UI / ED beam reporting, i.e., to not be associated with the existing AP-CSI reporting configuration, may be further explored.

[0305] In the UI / ED beam report transmission procedure, at least Option 1 may be supported for resource mapping / configuration between the first uplink channel and the second uplink channel of Mode B.

[0306] Option 1: One-to-one

[0307] Only a single periodic PUCCH resource for the first channel and a single pre-configured resource for the second uplink channel can be associated with the CSI reporting configuration for UI / ED beam reporting.

[0308] Option 1A: The first PUCCH resource and the second uplink channel resource have the same periodicity.

[0309] Option 1B: There is no periodicity limit between the two resources.

[0310] In the UI / ED beam report transmission procedure, when the Type-1 CG PUSCH pre-configured as the second uplink channel of Mode B transmits the beam report, at least the following Option 3 may be supported.

[0311] Option 1: The same Type-1 CG PUSCH can carry UL-SCH, other UCI, and beam reporting together.

[0312] Option 2: Type-1 CG PUSCH is a dedicated Type-1 CG PUSCH for carrying beam reports. Here, the PUSCH cannot carry UL-SCH or other UCI.

[0313] Option 3: Type-1 CG PUSCH is a Type-1 CG PUSCH intended to carry beam reports. Here, the PUSCH cannot carry UL-SCH, but can carry other UCIs.

[0314] The operations of the method according to the present disclosure can be implemented as a computer-readable program or code on a computer-readable recording medium. A computer-readable recording medium includes any type of recording device that stores information readable by a computer system. Furthermore, a computer-readable recording medium can be distributed across network-connected computer systems, allowing the computer-readable program or code to be stored and executed in a distributed manner.

[0315] Additionally, the computer-readable recording medium may include hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, flash memory, etc. The program instructions may include not only machine language codes produced by a compiler, but also high-level language codes that can be executed by a computer using an interpreter, etc.

[0316] While some aspects of the present disclosure have been described in the context of a device, they may also represent a description of a corresponding method, wherein a block or device corresponds to a method step or a feature of a method step. Similarly, aspects described in the context of a method may also be described as a corresponding block or item or a feature of a corresponding device. Some or all of the method steps may be performed by (or using) a hardware device, such as, for example, a microprocessor, a programmable computer, or an electronic circuit. In some embodiments, at least one or more of the most significant method steps may be performed by such a device.

[0317] A programmable logic device (e.g., a field-programmable gate array) may be used to perform some or all of the functions of the methods described in the present disclosure. The field-programmable gate array may operate in conjunction with a microprocessor to perform one of the methods described in the present disclosure. In general, the methods are preferably performed by some hardware device.

[0318] Although the present disclosure has been described with reference to preferred embodiments thereof, it will be understood by those skilled in the art that various modifications and changes may be made to the present disclosure without departing from the spirit and scope of the present disclosure as set forth in the claims below.

[0319] The present disclosure can be used in devices and recording media in wireless communication systems.

Claims

1. In a method of operating a terminal in a wireless communication system, Step of establishing a connection with a base station; A step of receiving an RRC (radio resource control) configuration message from the base station; A step of receiving at least one reference signal from the base station; A step of detecting beam failure based on at least one reference signal; generating a beam reporting message based on the measurement results of at least one reference signal; and A method comprising the step of transmitting the beam report message to the base station.

2. In claim 1, The step of detecting the above beam failure is: a step of measuring channel quality for at least one reference signal; and A method comprising the step of confirming that the above quality is below a first threshold.

3. In claim 2, A method wherein transmission of the beam report message is triggered in response to a single detection that the channel quality for at least one reference signal is below the first threshold.

4. In claim 2, A method wherein transmission of the beam report message is triggered in response to detection of a channel quality for at least one reference signal being below the first threshold a predefined or set number of times.

5. In claim 1, A method wherein the RRC configuration message includes information about a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH) for transmitting the beam report message.

6. In claim 1, A method wherein the step of generating the beam report message includes information about at least one candidate beam to be used for communication with the base station.

7. In claim 6, A method wherein the RRC configuration message includes information on conditions for determining the at least one candidate beam.

8. In claim 7, Information about the above conditions includes a second threshold for channel quality, A method wherein the at least one candidate beam comprises at least one beam providing a channel quality higher than the second threshold.

9. In claim 1, A method wherein the RRC configuration message includes information about a report quantity included in the beam report message.

10. In claim 1, The above beam report message is transmitted based on CFRA (contention-free based random access).

11. In claim 10, A method wherein the RRC configuration message includes information about a dedicated preamble or dedicated sequence for the CFRA.

12. In claim 1, The step of transmitting the above beam report message is: a step of transmitting a preamble indicating at least one candidate beam; and A method comprising the step of transmitting information about at least one candidate beam via a PUSCH corresponding to the preamble, 13. In claim 12, A method further comprising the step of receiving a response message for the PUSCH including information indicating whether to change to the at least one candidate beam.

14. In claim 1, Further comprising the step of receiving information indicating activation of beam reporting, A method in which information indicating activation of the above beam report is transmitted via MAC-CE or DCI (downlink control information).

15. In a method of operating a base station in a wireless communication system, Step of establishing a connection with a terminal; A step of transmitting an RRC (radio resource control) configuration message to the terminal; A step of transmitting at least one reference signal to the terminal; A step of receiving a beam report message from the terminal, Beam failure is detected based on at least one reference signal, A method wherein the beam report message is received in response to a beam report being triggered by the terminal based on a measurement result of at least one reference signal.

16. In claim 15, A method in which the RRC configuration message includes at least one of information about a physical uplink control channel (PUCCH) or a physical uplink shared channel (PUSCH) for transmitting the beam report message, information about a condition for determining at least one candidate beam included in the beam report message, information about a report quantity included in the beam report message, or information about a dedicated preamble or dedicated sequence for the beam report using contention-free based random access (CFRA).

17. In claim 15, The above beam report message is received through a preamble transmitted from the terminal based on CFRA and a PUSCH corresponding to the preamble.

18. In claim 17, A method further comprising the step of transmitting a response message for the PUSCH including information indicating whether to change to at least one candidate beam included in the beam report message.

19. In a wireless communication system, at a terminal, At least one transmitter / receiver; at least one processor; and At least one memory operably connected to said at least one processor and storing instructions that, when executed by said processor, control said terminal to perform operations; The above actions are, Step of establishing a connection with a base station; A step of receiving an RRC (radio resource control) configuration message from the base station; A step of receiving at least one reference signal from the base station; A step of detecting beam failure based on at least one reference signal; generating a beam reporting message based on the measurement results of at least one reference signal; and A terminal comprising a step of transmitting the beam report message to the base station.

20. In a base station in a wireless communication system, At least one transmitter / receiver; at least one processor; and At least one memory operably connected to said at least one processor and storing instructions that, when executed by said processor, control said base station to perform operations; The above actions are, Step of establishing a connection with a terminal; A step of transmitting an RRC (radio resource control) configuration message to the terminal; A step of transmitting at least one reference signal to the terminal; A step of receiving a beam report message from the terminal, Beam failure is detected based on at least one reference signal, A base station, wherein the beam report message is received in response to a beam report being triggered by the terminal based on a measurement result of at least one reference signal.

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