Method and apparatus for beam switching in multi-TRP system

Abstract

A method and an apparatus for beam switching in a multi-TRP system are disclosed. The method performed by an UE comprises the steps of: receiving, from a first TRP and / or a second TRP connected to a base station, a message including information indicating one or more TCI states for uplink transmission; and, if a PUCCH resource is positioned after an application time of the one or more TCI states, performing the uplink transmission on the basis of the one or more TCI states in the PUCCH resource, wherein, if the PUCCH resource is positioned before the application time, the uplink transmission in the PUCCH resource is performed on the basis of at least one TCI state that differs from the one or more TCI states.

Description

Method and device for beam switching in a multi-TRP system

[0001] The present disclosure relates to improved communication technologies, and more particularly, to dynamic beam switching technologies in communication systems supporting multiple transmission and reception points (TRPs).

[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, multiple transmission and reception points (mTRPs) can be introduced into communication networks (e.g., 5G and / or 6G). mTRPs can be geographically separated. Base stations can use mTRPs to communicate with terminals. mTRP technology can be used to address quality of service (QoS) degradation issues for cell-edge terminals and / or inter-cell interference issues. mTRP technology can also be used to provide additional communication paths in environments where non-line-of-sight (NLOS) paths are limited.

[0005] mTRP-based communication can be performed based on either the coherent joint transmission (CJT) scheme or the non-CJT (NCJT) scheme. In the CJT scheme, mTRP can perform cooperative communication based on a stable backhaul link and provide synchronized communication services to terminals. In the NCJT scheme, mTRP can provide communication services to terminals without cooperation. For example, in the NCJT scheme, mTRP can perform scheduling operations, precoding matrix selection operations, and modulation and coding scheme (MCS) determination operations without cooperation.

[0006] In mTRP-based communications, a terminal can transmit an UL (uplink) channel to one or more TRPs. In this case, it may be necessary for the terminal to pre-configure a beam for UL channel transmission. The timing of UL channel transmission may vary depending on the terminal's capabilities, which can lead to ambiguity in beam configuration for UL channel transmission. Therefore, beam configuration rules may be necessary to address this issue.

[0007] The purpose of the present disclosure to solve the above problems is to provide a method and device for dynamic beam switching in a communication system supporting multiple transmission and reception points (TRPs).

[0008] According to embodiments of the present disclosure for achieving the above object, a method of a UE includes the steps of receiving a message including information indicating one or more TCI states for uplink transmission from at least one TRP among a first TRP or a second TRP connected to a base station, and performing the uplink transmission on the PUCCH resource based on the one or more TCI states when a PUCCH resource is located after an application time of the one or more TCI states, wherein when the PUCCH resource is located before the application time, the uplink transmission on the PUCCH resource is performed based on at least one TCI state different from the one or more TCI states.

[0009] The method of the UE may further include the steps of receiving DCI including downlink scheduling information from the at least one TRP, and receiving data from the at least one TRP on a PDSCH resource scheduled by the DCI, wherein the uplink transmission may include transmission of a HARQ response for the data.

[0010] The at least one TCI state may be a TCI state(s) used for receiving a DCI scheduling a PDSCH resource associated with a HARQ response transmitted on the PUCCH resource.

[0011] The above TCI state(s) may be TCI state(s) associated with the CORESET pool from which the DCI is received.

[0012] The at least one TCI state may be a TCI state(s) used for uplink transmission prior to receipt of the message including information indicating the one or more TCI states.

[0013] The at least one TCI state may be a TCI state(s) for a PUCCH set by RRC signaling of the base station, and the TCI state(s) may be set independently from the one or more TCI states.

[0014] The at least one TCI state may be the TCI state(s) used for the most recent PUCCH transmission.

[0015] The at least one TCI state may be a TCI state(s) indicated by a MAC CE transmitted by the base station, and the TCI state(s) may be set independently from the one or more TCI states.

[0016] The at least one TCI state may be a TCI state(s) for a CORESET having the lowest ID among a plurality of CORESETs set by the base station.

[0017] The above message may further include information indicating whether default TCI state(s) are to be used, and if the default TCI state(s) are indicated to be used, the at least one TCI state may be the default TCI state(s), and if the default TCI state(s) are indicated to be not used, the at least one TCI state may be the TCI state(s) used for the most recent uplink transmission.

[0018] The above application time may be the sum of the processing time of the message and the time required for application of the one or more TCI states.

[0019] The above message can be received on PDSCH or PDCCH.

[0020] According to embodiments of the present disclosure for achieving the above object, a method of a base station includes the steps of transmitting to a UE a message including information indicating one or more TCI states for uplink transmission through at least one TRP from among a first TRP or a second TRP, and, when a PUCCH resource is located after an application time of the one or more TCI states, receiving the uplink transmission from the UE on the PUCCH resource based on the one or more TCI states, wherein when the PUCCH resource is located before the application time, a receiving operation for the uplink transmission on the PUCCH resource is performed based on at least one TCI state different from the one or more TCI states.

[0021] The at least one TCI state may be a TCI state(s) used for transmission of a DCI scheduling a PDSCH resource associated with a HARQ response received on the PUCCH resource.

[0022] The at least one TCI state may be a TCI state(s) used for a reception operation for uplink transmission prior to transmission of the message including information indicating the one or more TCI states.

[0023] The at least one TCI state is a TCI state(s) for PUCCH set by RRC signaling of the base station, and the TCI state(s) can be set independently from the one or more TCI states.

[0024] The at least one TCI state may be the TCI state(s) used for receiving operation for the most recent PUCCH transmission.

[0025] The at least one TCI state may be a TCI state(s) indicated by a MAC CE transmitted by the base station, and the TCI state(s) may be set independently from the one or more TCI states.

[0026] The at least one TCI state may be a TCI state(s) for a CORESET having the lowest ID among a plurality of CORESETs set by the base station.

[0027] The above message may further include information indicating whether default TCI state(s) are to be used, and if the default TCI state(s) are indicated to be used, the at least one TCI state may be the default TCI state(s), and if the default TCI state(s) are indicated to be not used, the at least one TCI state may be the TCI state(s) used for a receive operation for the most recent uplink transmission.

[0028] According to the present disclosure, a base station can transmit a message including indication information of a transmission configuration indicator (TCI) state for physical uplink control channel (PUCCH) transmission to a terminal. The terminal can determine a TCI state (e.g., a transmission beam) applicable for PUCCH transmission based on the indication information of the TCI state, and perform PUCCH transmission based on the determined TCI state. Accordingly, the ambiguity problem regarding the TCI state for PUCCH transmission can be resolved, and the performance of uplink (UL) communication can be improved.

[0029] Figure 1 is a conceptual diagram illustrating embodiments of a communication system.

[0030] Figure 2 is a block diagram illustrating embodiments of communication nodes constituting a communication system.

[0031] Figure 3 is a block diagram illustrating embodiments of communication nodes that perform communication.

[0032] Figure 4a is a block diagram illustrating embodiments of a transmission path.

[0033] Figure 4b is a block diagram illustrating embodiments of a receiving path.

[0034] Figure 5 is a conceptual diagram illustrating embodiments of system frames in a communication system.

[0035] Figure 6 is a conceptual diagram illustrating embodiments of subframes in a communication system.

[0036] Figure 7 is a conceptual diagram illustrating embodiments of slots in a communication system.

[0037] Figure 8 is a conceptual diagram illustrating embodiments of time-frequency resources in a communication system.

[0038] FIG. 9 is a conceptual diagram illustrating embodiments of the minimum time between PDSCH reception and PUCCH transmission and PUCCH transmission.

[0039] FIG. 10 is a conceptual diagram illustrating embodiments of minimum time and beam application between PDSCH reception and PUCCH transmission.

[0040] FIG. 11 is a conceptual diagram illustrating embodiments of PUCCH transmission according to the application time of TCI state(s) (e.g., update of TCI state(s)).

[0041] FIG. 12 is a conceptual diagram illustrating embodiments of a method for transmitting an RRC message including an indication of TCI state(s) for PUCCH resources.

[0042] 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.

[0043] 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.

[0044] 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.”

[0045] 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.”

[0046] 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.

[0047] 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.

[0048] 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.

[0049] 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.

[0050] 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.

[0051] 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.

[0052] 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)).

[0053] 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.”

[0054] The communication network to which the embodiment is applied is not limited to what is described below, and the embodiment may be applied to various communication networks (e.g., 4G communication networks, 5G communication networks, and / or 6G communication networks). Here, the communication network may be used in the same sense as the communication system.

[0055] Figure 1 is a conceptual diagram illustrating embodiments of a communication system.

[0056] 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.

[0057] 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.

[0058] Figure 2 is a block diagram illustrating embodiments of communication nodes constituting a communication system.

[0059] Referring to FIG. 2, a communication node (200) may include at least one processor (210), a memory (220), and a transmission / reception device (230) that is connected to a network and performs communication. In addition, the communication node (200) may further include an input interface device (240), an output interface device (250), a storage device (260), etc. Each component included in the communication node (200) may be connected by a bus (270) and communicate with each other.

[0060] The processor (210) can execute program commands stored in at least one of the memory (220) and the storage device (260). The processor (210) may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor in which the methods according to embodiments of the present disclosure are performed. Each of the memory (220) and the storage device (260) may be configured with at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory (220) may be configured with at least one of a read-only memory (ROM) and a random access memory (RAM).

[0061] 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).

[0062] 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.

[0063] 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.

[0064] 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.

[0065] 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.

[0066] 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.

[0067] 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 communication node illustrated in Fig. 2.

[0068] Figure 3 is a block diagram illustrating embodiments of communication nodes that perform communication.

[0069] Referring to FIG. 3, each of the first communication node (300a) and the second communication node (300b) may be a base station or a UE. The first communication node (300a) may transmit a signal to the second communication node (300b). The transmission processor (311) included in the first communication node (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 configured by RRC signaling), MAC control information (e.g., MAC CE), or PHY control information (e.g., DCI, SCI).

[0070] 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.

[0071] 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).

[0072] Signals transmitted by the first communication node (300a) may be received by antennas (364a to 364r) of the second communication node (300b). Signals received by the antennas (364a to 364r) may be provided to demodulators (DEMODs) included in 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).

[0073] Meanwhile, the second communication node (300b) can transmit a signal to the first communication node (300a). The transmitting processor (368) included in the second communication node (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).

[0074] 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).

[0075] Signals transmitted by the second communication node (300b) may be received by the antennas (314a to 314r) of the first communication node (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).

[0076] 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.

[0077] FIG. 4a is a block diagram illustrating embodiments of a transmission path, and FIG. 4b is a block diagram illustrating embodiments of a reception path.

[0078] 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.

[0079] 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.

[0080] 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.

[0081] 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.

[0082] 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.

[0083] 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.

[0084] Figure 5 is a conceptual diagram illustrating embodiments of a system frame in a communication system.

[0085] 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.

[0086] 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."

[0087] Figure 6 is a conceptual diagram illustrating embodiments of subframes in a communication system.

[0088] 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.

[0089] Figure 7 is a conceptual diagram illustrating embodiments of slots in a communication system.

[0090] Referring to FIG. 7, a single slot may include one or more symbols. A single slot illustrated in FIG. 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 numerology.

[0091] 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 a first 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.

[0092]

[0093] 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.

[0094] 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.

[0095] 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."

[0096] 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.

[0097] 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, a control channel may mean a PDCCH, a PUCCH, or a PSCCH, and a data channel may mean a PDSCH, a PUSCH, or a PSSCH.

[0098] Figure 8 is a conceptual diagram illustrating embodiments of time-frequency resources in a communication system.

[0099] 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.

[0100] 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.

[0101] 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.

[0102] 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.

[0103] CORESET information may include PDCCH DMRS (demodulation reference signal) information, PDCCH precoding information, PDCCH occasion information, etc. The PDCCH DMRS may be a DMRS used to demodulate the PDCCH. The PDCCH occasion may be a region where the PDCCH can exist. That is, the PDCCH occasion may be a region where DCI can be transmitted. The PDCCH occasion may be referred to as a PDCCH candidate. The PDCCH occasion information may include time resource information and frequency resource information of the PDCCH occasion. In the time domain, the length of the PDCCH occasion may be indicated in symbol units. In the frequency domain, the size of the PDCCH occasion may be indicated in RB units (e.g., in PRB (physical resource block) units or CRB (common resource block) units).

[0104] The search space information may include a coreset identifier (ID) associated with the search space, a period of PDCCH monitoring, and / or an offset. The period and offset of PDCCH monitoring may each 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.

[0105] 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).

[0106] Meanwhile, a communication system (e.g., NR communication system, 5G communication system, 6G communication system) may support usage scenarios such as enhanced Mobile BroadBand (eMBB), Ultra Reliable Low Latency Communication (URLLC), and massive Machine Type Communication (mMTC). A communication system (e.g., a communication network) may support transmission and reception point (TRP) technology (e.g., multiple TRP (mTRP) technology and / or single TRP (sTRP) technology). A communication system supporting the TRP technology may be referred to as a TRP system (e.g., mTRP system and / or sTRP system). In the present disclosure, TRP may have a meaning including sTRP and / or mTRP, and TRP may mean sTRP or mTRP depending on the context. TRP may mean an antenna set, an antenna group, and / or an antenna array. A TRP may be associated with a CORESET and / or a beam (e.g., a beam group).

[0107] mTRP technology may fall under the category of MIMO technology. mTRP may have characteristics (e.g., level characteristics) of macrocells, small cells, picocells, and / or femtocells. mTRP can perform data transmission for a single terminal. In a channel (e.g., a link) with uneven channel conditions due to obstacles and / or interference, mTRP can attenuate the effects of the obstacles and / or interference. mTRP can improve the data transmission rate for terminals located at cell edge areas.

[0108] mTRP-based communication can be performed using either coherent joint transmission (CJT) or non-CJT (NCJT) methods. In CJT, the base station can obtain channel information between each mTRP and the terminal and perform preprocessing on the data based on this channel information. In this case, the overhead associated with transmitting channel information may increase, and synchronization constraints between TRPs may arise. In NCJT, the base station may not need to know the channel information between each mTRP and the terminal. mTRPs can transmit data to the terminal without performing preprocessing operations such as phase compensation. The complexity of NCJT may be lower than that of CJT.

[0109] NCJT-based mTRP communication can be performed based on a single DCI scheme or a multiple DCI scheme. In the single DCI scheme, PDSCHs transmitted by an mTRP can be scheduled by a single DCI. A single DCI can be transmitted by one TRP among the mTRPs. In the multiple DCI scheme, the PDSCHs transmitted by each TRP can be scheduled by the DCI transmitted by each TRP. For example, a first PDSCH transmitted by a first TRP can be scheduled by a first DCI transmitted by the first TRP, and a second PDSCH transmitted by a second TRP can be scheduled by a second DCI transmitted by the second TRP. In other words, multiple PDSCHs can be scheduled using multiple DCIs.

[0110] In a single SCI scheme, a terminal can expect to receive PDSCHs transmitted by different TRPs over the same time and frequency resources and across different layers. Alternatively, the terminal can expect to receive PDSCHs transmitted by different TRPs over the same frequency resources and across the same layer but across different time resources (e.g., across different time domains). Alternatively, the terminal can expect to receive PDSCHs transmitted by different TRPs over the same time resources and across the same layer but across different frequency resources (e.g., across different frequency domains).

[0111] In a multi-DCI scheme, scheduling of PDSCHs for each TRP can be performed by a separate DCI. The PDSCHs scheduled by multiple DCIs may fully overlap or partially overlap. Alternatively, the PDSCHs scheduled by multiple DCIs may not overlap. In both single-DCI and multi-DCI schemes, the DCI may include transmission configuration indicator (TCI) status information for the PDSCH.

[0112] The indication / setting of the TCI state for the terminal can be interpreted as the indication / setting of a beam (e.g., a transmit beam and / or a receive beam). In other words, the TCI state can have a meaning corresponding to the beam. From the perspective of DL (downlink) communication, the setting of the TCI state can mean the setting of QCL (quasi co-location). From the perspective of UL (uplink) communication, the setting of the TCI state can mean the setting of a spatial filter. The unified TCI state can indicate (e.g., set) a common beam regardless of DL communication and UL communication. Alternatively, the unified TCI state can indicate (e.g., set) a common beam for each of DL communication and UL communication. The unified TCI can be referred to as UTCI.

[0113] Enhancements (e.g., PDCCH enhancements) may be implemented to improve the reliability and / or robustness of mTRP communications. Deployment scenarios for PDCCH enhancements can be categorized into single frequency network (SFN) and non-SFN scenarios.

[0114] In the SFN scheme, different TRPs or different panels can transmit the same PDCCH using the same resources (e.g., the same time resources, the same frequency resources, and / or the same spatial resources). In other words, all TRPs or all panels can transmit the same PDCCH using the same DMRS configuration, the same DMRS location, and / or the same DMRS sequence. At this time, the TCI states for the reception perspective of the TRPs or panels can be implicitly set differently. The above embodiment can be performed based on multiple TCI states of the CORESET. There may be synchronization constraints for ideal or near-ideal backhaul between TRPs.

[0115] In the NSFN scheme, the PDCCH generated from each TRP can be multiplexed in the time domain and / or frequency domain, and the multiplexed PDCCH can be transmitted to the terminal. The scheme may be an mTRP-based PDCCH repetition scheme. In the NSFN scheme, the same number of bits as the encoded bits transmitted through one PDCCH generated from each TRP can be divided for each TRP, and the bits (e.g., encoded bits) for each TRP can be transmitted through different PDCCH candidates. The scheme may be an sTRP-based PDCCH transmission scheme.

[0116] In the mTRP-based PDCCH repetition scheme, the PDCCH can be repeatedly generated as many times as the number of TRPs, and the PDCCH can be transmitted in the same search space (e.g., search spaces having the same index) within different search space sets having the same number of PDCCH candidates. At this time, the search space sets can exist within the same CORESET or different CORESETs. Since one TCI state can be associated with each CORESET, when the PDCCH is transmitted in different search spaces within the same CORESET, only one TCI state can be indicated (e.g., set) for the PDCCHs transmitted in the different search spaces. In this case, the UE can receive the PDCCH from one TRP at a specific time.

[0117] When a PDCCH is transmitted in the same search space within different CORESETs, the UE can implicitly expect to receive the PDCCH from either the sTRP or the mTRP, depending on the number of TCI states (e.g., TCI states indicated or configured by the base station). In this case, a single PDCCH can be split as many times as the number of TRPs, and the split PDCCHs can be transmitted on different PDCCH candidates. At this time, the aggregation level and the combined aggregation level can be the same. In the above embodiment, the PDCCH candidates can be assigned to different CORESETs. The payload size for the final distributed PDCCH combination can be the same as the payload size of the PDCCH transmitted in the sTRP. Therefore, in terms of decoding complexity, the sTRP-based PDCCH transmission scheme can be advantageous over the mTRP-based PDCCH repetition scheme.

[0118] A terminal can perform mTRP communication or sTRP communication with a base station. mTRP communication between the terminal and the base station can be performed through an mTRP associated with the base station. sTRP communication between the terminal and the base station can be performed through an sTRP associated with the base station. mTRP communication may be referred to as first TRP communication, and sTRP communication may be referred to as second TRP communication. Alternatively, mTRP communication may be referred to as second TRP communication, and sTRP communication may be referred to as first TRP communication. "The terminal performs first TRP communication with the base station" may mean "the terminal performs mTRP communication or sTRP communication with the base station through one or more TRPs associated with the base station." "The terminal performs second TRP communication with the base station" may mean "the terminal performs sTRP communication or mTRP communication with the base station through one or more TRPs associated with the base station."

[0119] In a communication system, integrated TCI can be supported. A base station can transmit information about a pool (e.g., a list) of TCI states to a terminal using RRC signaling. The terminal can receive information about a pool (e.g., a list) of TCI states through RRC signaling from the base station. The base station can set type information about the TCI state to the terminal. The type information can be a joint DL / UL beam indication or a separate DL / UL beam indication. A joint DL / UL beam indication can be referred to as a 'joint indication or joint type.' An independent DL / UL beam indication can be referred to as an 'independent indication or independent type.'

[0120] When a joint type (e.g., joint indication) is set, TCI states (e.g., one TCI state) for DL ​​and UL may be set. In other words, DL TCI state setting and UL TCI state setting may be the same. The UE may expect that the TCI state indicated by the information element included in the PDSCH configuration information applies to both DL (e.g., DL signal / channel) and UL (e.g., UL signal / channel). The signal / channel may refer to a signal and / or a channel. When an independent type (e.g., independent indication) is set, TCI states for DL ​​and UL may be set respectively. In other words, DL TCI state setting may be distinguished from UL TCI state setting. The UE may expect that the UL TCI state indicated by the information element included in the UL BWP configuration information applies to UL (e.g., UL signal / channel). The UL signal / channel may include a PUSCH, a PUCCH, and / or an SRS.

[0121] After the pool (e.g., pool list) for TCI states is configured (e.g., indicated) by RRC signaling, the base station can use DCI (e.g., DCI signaling) to indicate the TCI state (e.g., application of the TCI state). Due to the constraint of the DCI size (e.g., bits in the DCI field), the base station can preferentially activate candidate TCI state(s) using MAC signaling (e.g., MAC CE signaling). In other words, as many (e.g., maximum number) candidate TCI state(s) as can be indicated (e.g., configured) via DCI can be preferentially activated by MAC CE.

[0122] For the activated candidate TCI state(s), the DCI may contain code points corresponding to a single TCI state or two TCI states, depending on the TCI state type (e.g., joint type or independent type). If the joint type is set, the code points corresponding to a single TCI state may be conveyed by the DCI. If the independent type is set, the code points corresponding to two TCI states may be conveyed by the DCI.

[0123] In a communication system supporting integrated TCI, the reception operation of a PDSCH can be performed as follows. A terminal can receive a DCI and check the indication information of the TCI state(s) included in the DCI. The terminal can expect to receive the PDSCH by applying the TCI state(s) indicated (e.g., configured) by the DCI after a certain period of time (e.g., beam application time (BAT)). Meanwhile, the PDSCH can be transmitted before the BAT. To receive the PDSCH before the BAT, a TCI selection field can be introduced. The terminal can expect to receive the PDSCH before the BAT based on the TCI selection field. In other words, the TCI selection field can dynamically indicate PDSCH reception before the BAT. The TCI selection field can be included in the DCI. Whether the TCI selection field is present in the DCI can be preset by RRC signaling. The terminal can check whether the DCI includes the TCI selection field based on the setting by the RRC signaling.

[0124] Regardless of whether a TCI selection field exists in the DCI, a terminal can receive DCI (e.g., PDCCH), decode information included in the DCI, and set a beam for PDSCH reception based on the decoded information. Beam setting may mean determining a TCI state. The ability to set a beam for PDSCH reception may vary from terminal to terminal. In a PDSCH reception procedure of a single DCI-based mTRP communication, the time required for applying a TCI state (e.g., a minimum time) may vary from terminal to terminal, and accordingly, rules for setting a PDSCH reception beam may be required.

[0125] Unified TCI can be extended to mTRP communications (e.g., mTRP systems). The base station can dynamically indicate (e.g., configure) the TCI state(s) used for PUCCH transmission to the UE. During the TCI state(s) configuration procedure, the relationship between PUCCH resources and TRP states can be explicitly or implicitly indicated (e.g., configured). In single-DCI-based mTRP communications and / or multi-DCI-based mTRP communications, the UE's transmit beam (Tx beam) used for PUCCH transmission can be configured.

[0126] In order for a terminal to apply the TCI state(s) indicated / configured by the base station, a minimum time may be required for receiving an RRC message indicating the TCI state(s) and / or decoding the RRC message. The minimum time may be similar to the scheduling offset (e.g., time offset) between the PDCCH and the PDSCH.

[0127] Methods for setting a beam of a terminal for PDSCH reception and / or PUSCH transmission in single DCI-based mTRP communication will be described. Embodiments of the present disclosure can be applied not only to single DCI-based mTRP communication but also to multi-DCI-based mTRP communication. sTRP communication can support integrated TCI, and the integrated TCI can be extended to mTRP communication. TCI state(s) related to PUCCH transmission can be set. TCI state(s) related to PUCCH transmission (e.g., transmission beam(s)) can be indicated (e.g., set) by RRC signaling. TCI state(s) related to PUCCH transmission can be dynamically indicated (e.g., set). TCI state(s) indicated by RRC signaling can be applied to PUCCH resource(s). Setting of TCI state(s) can mean setting of transmission beam(s).

[0128] In other words, the base station can transmit to the terminal an RRC message including information (e.g., list information) of TCI state(s) for uplink transmission. The TCI state(s) can be set for each uplink channel and / or uplink signal. The base station can transmit to the terminal a MAC CE including information indicating TCI state(s) to be activated among the TCI state(s) set by RRC signaling. Transmission of the MAC CE indicating the TCI state(s) to be activated may be omitted. The base station can transmit to the terminal a DCI (e.g., a DCI for scheduling downlink transmission and / or uplink transmission) including information indicating one or more TCI states used for uplink transmission among the TCI state(s) activated by the MAC CE. One or more TCI states used for uplink transmission can be set (e.g., indicated) to the terminal based on at least one of RRC signaling, MAC CE signaling, or PHY signaling (e.g., DCI signaling). The terminal can perform uplink transmission using one or more TCI state(s) set based on the above signaling.

[0129] Depending on the capability of the terminal in the procedure of transmitting and receiving a signal and / or channel, a processing time for the signal and / or channel, a preparation time for transmitting the signal and / or channel, etc. may be required. For example, a PDCCH processing time and / or a PDSCH processing time may be required, and a PUSCH preparation time and / or a PUCCH preparation time may be required. PUCCH resources for transmitting a hybrid automatic repeat request (HARQ) response to the PDSCH may be scheduled considering the required time according to the capability of the terminal. Time constraints for PUCCH (e.g., scheduling of PUCCH resources) may not take into account the beam switching time. In scheduling not only PUCCH for transmitting a HARQ response to the PDSCH but also PUCCH for transmitting a scheduling request (SR) and / or channel state information (CSI), it may be necessary to consider the beam switching time. CSI may include a precoding matrix indicator (PMI), a rank indicator (RI), a layer indicator (LI), a channel quality indicator (CQI), a CSI reference resource indicator (CRI), an SS / PBCH block resource indicator (SSBRI), and / or a reference signal received power (RSRP).

[0130] Additional time constraints (e.g., physical time constraints) may be considered for operations in which a terminal receives information from a base station, processes (e.g., decodes) the received information, and / or applies information indicated / set by the processed information to a target (e.g., PUCCH, PUSCH). The terminal may operate while taking the above time constraints into account.

[0131] A terminal can transmit uplink control information (UCI) via PUSCH and / or PUCCH. Multiple PUCCH formats can be defined depending on the type and / or size of information included in the UCI. For example, five PUCCH formats can be supported. The five PUCCH formats can include PUCCH format #0, PUCCH format #1, PUCCH format #2, PUCCH format #3, and PUCCH format #4. Information about the PUCCH format can be included in PUCCH configuration information. The base station can transmit the PUCCH configuration information to the terminal using RRC signaling. The PUCCH configuration information can be configured for each terminal. The PUCCH configuration information can include time information (e.g., timing information) of the PUCCH resource.

[0132] PUCCH resources for transmitting a HARQ response to a PDSCH may be determined based on a timing indicator included in DCI (e.g., a PDSCH-to-HARQ_feedback timing indicator). PUCCH resources for transmitting a HARQ response to a PDSCH may be determined based on values ​​set by RRC signaling (e.g., dl-DataToUL-ACK, dl-DataToUL-ACK-r16, dl-DataToUL-ACK-DCI-1-2, dl-DataToUL-ACK-r17, dl-DataToUL-ACK-DCI-1-2-r17). A value indicating the location of a PUCCH resource in the time domain may be referred to as k. When a PDSCH is transmitted in slot n, the base station may expect to receive a PUCCH including a HARQ response to the PDSCH from the terminal in slot n+k.

[0133] A minimum required time for transmitting a HARQ response (e.g., a PUCCH containing the HARQ response) for PDSCH reception may be defined. The minimum required time may vary depending on the capabilities of the terminal. The minimum required time may be defined as shown in Mathematical Expression 1 below.

[0134]

[0135] may mean the minimum required time for transmitting a HARQ response for PDSCH reception. The values ​​and / or definitions of the variables in Equation 1 may be identical to those specified in TS 38.214. The minimum time required for PUCCH transmission, such as the above, can be defined as processing time. The processing time may refer to the time excluding the time required for beam establishment. The processing time may include "the time to receive a channel (e.g., a signal)" + "the time to decode information included in the received channel." Alternatively, the processing time may include "the time to receive a channel (e.g., a signal)" + "the time to decode information included in the received channel" + "the time to prepare an action based on the decoded information."

[0136] FIG. 9 is a conceptual diagram illustrating embodiments of the minimum time between PDSCH reception and PUCCH transmission and PUCCH transmission.

[0137] Referring to FIG. 9, a base station can transmit a PDSCH to a terminal. The terminal can receive the PDSCH from the base station and transmit a PUCCH (e.g., UCI) including an HARQ response to the PDSCH to the base station. The above operation can be performed in an mTRP system. In other words, the PDSCH of the base station can be transmitted to the terminal through one or more TRPs, and the PUCCH of the terminal can be transmitted to the base station through one or more TRPs. The transmission time of the PUCCH can vary depending on the capability of the terminal. The base station can allocate PUCCH transmission resources considering the capability of the terminal. The terminal can transmit the PUCCH after the processing time of the PDSCH (e.g., the minimum time required to process the PDSCH).

[0138] PUCCH can be used to transmit SR (scheduling request). The SR procedure can be performed based on the control of the MAC layer. When data to be transmitted from the terminal occurs, the MAC layer of the terminal can trigger the SR procedure. The terminal can transmit the PUCCH including the SR at the closest occasion (e.g., the earliest occasion) based on the time point at which the data to be transmitted occurs (e.g., the time point at which the SR procedure is triggered). Occasions for SR transmission (e.g., SR occasions, PUCCH occasions) can be set periodically. When the terminal has data to be transmitted, the terminal can transmit a positive SR at a PUCCH occasion. When the terminal does not have data to be transmitted, the terminal can transmit a negative SR at a PUCCH occasion.

[0139] Based on SR triggering with periodicity and integrated TCI state(s), when a change of separate TCI state(s) is required by RRC signaling, the UE may require time for updating the TCI state(s) for a preset PUCCH resource, time for receiving a PDSCH (e.g., an RRC message and / or MAC CE) containing information about the change (e.g., update) of the TCI state(s), and / or time for decoding the PDSCH. As another example, information about the change (e.g., update) of the TCI state(s) may be included in a separate DCI (e.g., DCI format 2_x). The DCI containing information about the change (e.g., update) of the TCI state(s) may be configured independently from the DCI for uplink scheduling (e.g., DCI format 0_x) and / or the DCI for downlink scheduling (e.g., DCI format 1_x). x may be an integer greater than or equal to 0.

[0140] When a base station requests an update of TCI state(s) from a terminal prior to a PUCCH transmission of the terminal, the terminal may require a minimum time required for receiving a message requesting an update of the TCI state(s), decoding the message, and / or updating the TCI state(s) based on the decoded information. The minimum time required for updating (e.g., applying) the TCI state(s) may be defined. A method for setting a beam for PUCCH resources existing before an end time of the minimum time and / or a method for setting a beam for PUCCH resources existing after an end time of the minimum time may be required. A beam may mean a TCI state. In other words, a beam and a TCI state may have corresponding meanings. An update of the TCI state(s) may mean an indication and / or a setting of the TCI state(s).

[0141] - Proposed Method #1: Introduction and Application of Thresholds for the Application of TCI State(s) Related to PUCCH Transmission

[0142] Regardless of single DCI-based mTRP communication and multi-DCI-based mTRP communication, TCI state(s) for PUCCH can be dynamically set (e.g., indicated) by RRC signaling (or MAC CE, DCI). If RRC signaling (e.g., RRC message) indicating TCI state(s) for PUCCH is transmitted through PDSCH, time for acquiring and / or applying information to TCI state(s) from RRC signaling (hereinafter, "beam application time") may be required at the terminal. The beam application time may mean the TCI application time. The beam application time is the minimum time required for PUCCH transmission (e.g., in Equation 1). ) may be the same as the processing time. The beam application time may mean “the decoding time of the PDSCH + the time to obtain information from the decoding result.”

[0143] Since the PDSCH includes information related to beam configuration (e.g., update information of TCI state(s)), the time for applying the beam information may be considered. Switching information (e.g., update information) for the TCI state(s) may be transmitted via the PDSCH (e.g., RRC signaling, MAC CE) or the PDCCH (e.g., DCI), and the TCI state(s) for the PUCCH resource(s) existing prior to reception of the switching information for the TCI state(s) may be different from the TCI state(s) indicated by the PDSCH (e.g., the RRC signaling). In this case, the terminal may require time for beam reconfiguration. If the TCI state(s) for the PUCCH resource(s) existing prior to reception of the switching information for the TCI state(s) are identical to the TCI state(s) indicated by the PDSCH (e.g., the RRC signaling), the terminal may not require time for beam reconfiguration. In this case, the terminal can perform uplink transmission based on the TCI state(s) indicated by the PDSCH without considering the beam application time.

[0144] A minimum time (e.g., beam application time, TCI application time) required for receiving a PDSCH and applying (e.g., updating, switching) TCI state(s) indicated by the PDSCH can be defined. The configuration (e.g., operation) of a transmission beam of a terminal can vary based on the beam application time. The beam configuration (e.g., TCI state(s)) applied to PUCCH resource(s) or PUCCH group existing (e.g., positioned) within the beam application time can be different from the beam configuration (e.g., TCI state(s)) applied to PUCCH resource(s) or PUCCH group existing outside the beam application time.

[0145] FIG. 10 is a conceptual diagram illustrating embodiments of minimum time and beam application between PDSCH reception and PUCCH transmission.

[0146] Referring to FIG. 10, a time interval including a PDSCH processing time and a beam application time can be defined. A terminal can expect that different transmission beams (e.g., different TCI states) are applied to PUCCH resource(s) existing within the time interval (e.g., before the end of the time interval (e.g., beam application time)) and PUCCH resource(s) existing outside the time interval (e.g., after the end of the time interval (e.g., beam application time)). The configuration of a transmission beam (e.g., TCI state(s)) in PUCCH resource region A may be different from the configuration of a transmission beam (e.g., TCI state(s)) in PUCCH resource region B. The required time for beam switching (e.g., switching of TCI state(s)) in PUCCH resource region A may not be considered. The time interval including the PDSCH processing time and the beam application time may be referred to as timedurationforTCI_PUCCH. Alternatively, timedurationforTCI_PUCCH can include only the beam application time.

[0147] The time required for beam switching (e.g., beam application) (e.g., beam application time) may vary for each terminal. The terminal may report the beam application time to the base station. The beam application time of the terminal may be transmitted to the base station in the UE capability reporting procedure. The base station may configure PUCCH resources and / or beams (e.g., TCI states) for PUCCH transmission by considering the beam application time of the terminal. The beam application time may be configured in units of subframes, slots, or symbols. The base station may transmit update information (e.g., switching information) on the TCI state(s) for uplink transmission to the terminal by considering the beam application time of the terminal.

[0148] The start time of timedurationforTCI_PUCCH may be the start symbol (e.g., the first symbol, the start time) or the end symbol (e.g., the last symbol, the end time) of the PDSCH (or PDCCH) through which the message indicating the update of the TCI state(s) is transmitted. Alternatively, the start time of timedurationforTCI_PUCCH may be the start symbol (e.g., the first symbol, the start time) or the end symbol (e.g., the last symbol, the end time) of the slot in which the PDSCH (or PDCCH) through which the message indicating the update of the TCI state(s) is transmitted is located. The start offset for PUCCH may be set in units of slots. The UE may check the PUCCH resource(s) or PUCCH group existing in the timedurationforTCI_PUCCH and the PUCCH resource(s) or PUCCH group existing outside of the timedurationforTCI_PUCCH based on the start time of timedurationforTCI_PUCCH. The terminal can apply different beams to PUCCH resource(s) or PUCCH group existing within timedurationforTCI_PUCCH and PUCCH resource(s) or PUCCH group existing outside of timedurationforTCI_PUCCH.

[0149] For example, in the PUCCH resource(s) or PUCCH group existing within timedurationforTCI_PUCCH, the UE can perform PUCCH transmission based on the existing beam(s) (e.g., existing TCI state(s)) without updating the beam configuration. The existing beam(s) may be the beam(s) used for the previous PUCCH transmission, the beam(s) used for the previous PUSCH transmission, the beam(s) used for the previous PDCCH reception, or the beam(s) used for the previous PDSCH reception. In the PUCCH resource(s) or PUCCH group existing outside of timedurationforTCI_PUCCH, the UE can perform PUCCH transmission based on the updated beam(s) (e.g., updated TCI state(s)). The base station may expect that "the terminal performs PUCCH transmission based on existing beam(s) (e.g., existing TCI state(s)) without updating beam configuration in the PUCCH resource(s) or PUCCH group existing within timedurationforTCI_PUCCH, and the terminal performs PUCCH transmission based on updated beam(s) (e.g., updated TCI state(s)) in the PUCCH resource(s) or PUCCH group existing outside of timedurationforTCI_PUCCH."

[0150] In other words, the base station can receive PUCCH transmissions from the terminal based on existing beam(s) (e.g., existing TCI state(s)) without updating beam configurations in the PUCCH resource(s) or PUCCH group existing within timedurationforTCI_PUCCH. The base station can receive PUCCH transmissions from the terminal based on updated beam(s) (e.g., updated TCI state(s)) in the PUCCH resource(s) or PUCCH group existing outside of timedurationforTCI_PUCCH.

[0151] - Proposed Method #2: UE behavior according to the interval between the indication time of TCI state(s) (e.g., configuration time) and PUCCH

[0152] The base station can configure (e.g., instruct) the terminal to configure TCI state(s) for PUCCH transmission through RRC signaling (or MAC CE, DCI). The terminal can check the configuration of TCI state(s) for PUCCH transmission through the RRC signaling of the base station. The terminal can perform PUCCH transmission based on the TCI state(s) instructed by the base station on the PUCCH resource(s) after timedurationforTCI_PUCCH. The terminal can perform PUCCH transmission based on the rule(s) below on the PUCCH resource(s) before timedurationforTCI_PUCCH. In other words, the terminal can perform PUCCH transmission based on the TCI state(s) according to the rule(s) below.

[0153] FIG. 11 is a conceptual diagram illustrating embodiments of PUCCH transmission according to the application time of TCI state(s) (e.g., update of TCI state(s)).

[0154] Referring to FIG. 11, a base station may configure PUCCH resources (e.g., PUCCH resource #1 and PUCCH resource #2) to a terminal. PUCCH resource #1 may be configured after the processing time for PDSCH. In other words, PUCCH resource #1 may start before the end of the beam application time (e.g., timedurationforTCI_PUCCH). PUCCH resource #2 may be configured after the end of the beam application time (e.g., timedurationforTCI_PUCCH). In other words, PUCCH resource #2 may start after the end of the beam application time (e.g., timedurationforTCI_PUCCH).

[0155] A base station may indicate TCI state(s) (e.g., update of TCI state(s)) for PUCCH transmission to a terminal. The TCI state(s) for PUCCH transmission may be included in an RRC message, a MAC CE, and / or a DCI. The DCI indicating the TCI state(s) for PUCCH transmission may be a DCI scheduling a PDSCH associated with a PUCCH (e.g., a PUCCH including a HARQ response). Alternatively, the DCI indicating the TCI state(s) for PUCCH transmission may be a separate DCI from the DCI scheduling a PDSCH transmission or a PUSCH transmission. When the TCI state(s) for PUCCH transmission are indicated, the terminal may apply the TCI state(s) indicated by the base station to the PUCCH resource(s) (e.g., PUCCH resource #2) existing after timedurationforTCI_PUCCH. In other words, the terminal can perform PUCCH transmission based on the TCI state(s) indicated by the base station on the PUCCH resource(s) (e.g., PUCCH resource #2) that exist (e.g., are located) after timedurationforTCI_PUCCH.

[0156] PUCCH resources may be allocated considering updates (e.g., application) to TCI state(s). However, considering resource utilization and / or quick response, PUCCH resources may be preset without considering updates (e.g., beam switching) to TCI state(s). PUCCH resources for SR transmission may be preset periodically. In other words, PUCCH resources for SR transmission may be preset without considering updates to TCI state(s). Accordingly, PUCCH resource #1 illustrated in FIG. 11 may be allocated. A method (e.g., rule) for beam configuration for PUCCH resource #1 may be required. The beam used for PUCCH transmission in PUCCH resource #1 may be defined as a default beam.

[0157] PUCCH resources can be configured cell-commonly or UE-specifically. PUCCH resources can be configured by RRC messages and / or system information. In other words, RRC messages and / or system information can include PUCCH configuration information. Since PUCCH resources are configured in advance by RRC messages and / or system information, the UE can know the PUCCH resources in advance. In other words, the UE can predict the PUCCH resources.

[0158] The PDCCH can schedule the PDSCH, and the HARQ response (e.g., HARQ-ACK (acknowledgement)) for the PDSCH can be transmitted on the PUCCH resource. The UE can know the PUCCH resource on which the HARQ response for the PDSCH will be transmitted before the decoding operation of the PDSCH is completed. Therefore, the UE can determine in advance whether to apply the TCI state(s) indicated by the base station on the PUCCH resource. The UE can determine which beam (e.g., which TCI state) to apply to which PUCCH resource, but since the performance may vary by UE, a rule for applying the beam may be necessary.

[0159] Based on the first rule, the terminal can determine the beam corresponding to the beam used for receiving the PDCCH scheduling the PDSCH as the transmit beam for the PUCCH resources existing within the timedurationforTCI_PUCCH by utilizing the characteristic of channel reciprocity. In other words, the default beam for PUCCH transmission may be the receive beam for the PDCCH scheduling the PDSCH associated with the PUCCH transmission. The TCI state(s) associated with the CORESET pool index may be used for PUCCH transmission within the timedurationforTCI_PUCCH. In multi-DCI based mTRP communication, TRPs may be implicitly distinguished by the CORESETpoolindex for the PDCCH. Single-DCI based mTRP communication may be performed based on the RRC configuration. In single-DCI based mTRP communication, the beam (e.g., TCI state) indicated for the PDCCH may be used as the transmit beam (e.g., TCI state) for the PUCCH.

[0160] Based on the second rule, the UE may apply the TCI state(s) (e.g., beam configuration) for the PUSCH (e.g., uplink transmission) prior to receiving the indication of the TCI state(s) (e.g., update indication, switching indication) for the PUCCH transmission within the timedurationforTCI_PUCCH. In other words, the default beam for the PUCCH transmission may be the transmit beam(s) (e.g., TCI state(s)) used for the PUSCH transmission prior to receiving the indication of the TCI state(s) (e.g., update indication, switching indication). The default beam for the PUCCH transmission may be determined based on the SRS resource set indicator or RRC signaling. The transmit power parameter(s) for the PUSCH may be used to determine the transmit power of the PUCCH. For a common RS for the transmit power of the PUSCH and the PUCCH, the value(s) (e.g., transmit power parameter(s)) applied to the PUSCH may be used.

[0161] Based on the third rule, the UE can apply a transmission beam (e.g., PUCCH-SpatialRelationInfo) for PUCCH resources configured by RRC signaling (e.g., UL dedicated BWP configuration including PUCCH resource configuration) within the timedurationforTCI_PUCCH for PUCCH transmission. The RRC signaling may be UE-specific RRC signaling, and the transmission beam for the PUCCH resources may be TCI state(s) for PUCCH. The RRC signaling for indication (e.g., update, switching) of the TCI state(s) for PUCCH may be independent from the RRC signaling for configuration of the PUCCH resources. The transmission power of the PUCCH may be configured based on a value for an initially configured RS. Alternatively, the spatial information may be used as is, and a value related to an RS used in a previous UL may be used as a value related to an RS for path loss.

[0162] Based on the fourth rule, the terminal may apply the beam (e.g., TCI state) used for the most recent PUCCH transmission for PUCCH transmission within the timedurationforTCI_PUCCH. The transmit power parameter(s) of the PUCCH within the timedurationforTCI_PUCCH may be identical to the transmit power parameter(s) of the most recent PUCCH. Alternatively, the terminal may determine the transmit power of the PUCCH based on the RS used in the most recent UL channel. This operation may be performed when TRP differentiation is possible.

[0163] Based on the fifth rule, the base station can transmit a MAC CE indicating TCI state(s) to the terminal, and the terminal can apply the TCI state(s) mapped to the lowest or highest codepoint among the multiple codepoints configured by the MAC CE for PUCCH transmission within the timedurationforTCI_PUCCH. The MAC CE indicating the TCI state(s) can be independent of the RRC signaling (e.g., RRC message) for indicating (e.g., updating, switching) the TCI state(s) for PUCCH. The MAC CE can be signaled to the terminal before transmitting the RRC message, or the MAC CE can be signaled to the terminal after transmitting the RRC message. The number of TCI states mapped to a codepoint can vary depending on the type of the integrated TCI state (e.g., joint or independent). For example, the number of TCI states mapped to a codepoint can be 1 or 2 depending on the type of the integrated TCI state. The number of TCI states mapped to a code point may vary depending on the number of TRPs. For example, if "the type of the unified TCI state is joint and two TRPs are supported," a code point may be mapped to two TCI states. For another example, if "the type of the unified TCI state is independent and two TRPs are supported," a code point may be mapped to four TCI states.

[0164] TCI state(s) per TRP may be referred to as a group TCI. A group TCI may have an index. A group TCI may be mapped to a codepoint. A UE may commonly apply the TCI state(s) belonging to the first group TCI to all PUCCH resources. The UE may sequentially apply the group TCI to PUCCH resources according to the index of the group TCI. The UE may sequentially apply the TCI states belonging to a group TCI to PUCCH resources according to the index of the TCI state. PUCCH resources may be distinguished by an index (e.g., ID). The TCI states belonging to a group TCI may be applied to PUCCH resources in descending or ascending order of the PUCCH resource index.

[0165] Based on the sixth rule, the UE can apply the QCL parameters of the CORESET associated with the lowest CORESET ID (index) for PUCCH transmission within timedurationforTCI_PUCCH. In other words, the base station can configure multiple CORESETs for the UE, and the UE can apply the TCI state(s) based on the QCL parameters of the CORESET with the lowest ID among the multiple CORESETs for PUCCH transmission within timedurationforTCI_PUCCH.

[0166] The terminal can determine TCI state(s) (e.g., beam(s)) for PUCCH transmission within timedurationforTCI_PUCCH based on one of the six rules described above, and perform PUCCH transmission based on the determined TCI state(s). The terminal can transmit information about the rule it uses to the base station through signaling. Alternatively, the base station can select one of the six rules described above, and transmit information about the selected rule to the terminal through signaling. The terminal can identify one rule indicated by the signaling of the base station, and determine TCI state(s) (e.g., beam(s)) for PUCCH transmission within timedurationforTCI_PUCCH based on the one rule, and perform PUCCH transmission based on the determined TCI state(s).

[0167] The above-described embodiments can be applied in the following situations. A terminal can check (e.g., predict) PUCCH resources allocated to it in the time domain and receive indications (e.g., update, switching) of TCI state(s) from a base station. If there are PUCCH resources to which the TCI state(s) indicated by the base station cannot be applied, the terminal can determine a beam for PUCCH transmission based on beam information already known (e.g., information on the TCI state). At this time, the terminal can determine a beam for PUCCH transmission based on the above-described rule. The beam information can be stored in a buffer of the terminal, and the terminal can utilize the beam information stored in the buffer. Although beam switching occurs, a separate processing procedure for PDSCH is not required, so the terminal can switch TCI state(s).

[0168] - Proposed method #3: Introduction of an additional indicator to indicate the default beam of the terminal (e.g., default TCI state) and a method for indicating the default beam using the additional indicator.

[0169] The operations of the terminal mentioned in the proposed method #2 described above can be applied depending on the environment(s). The base station can determine whether to use the default beam in the terminal, and can transmit information indicating whether to use the default beam to the terminal through signaling. The information indicating whether to use the default beam can be indicated by 1 bit. The information indicating whether to use the default beam can be included in an RRC message, and the RRC message can include update information on TCI state(s). In other words, the RRC message indicating an update on the TCI state(s) can include information indicating whether to use the default beam. The default beam can be a beam used for a previous uplink transmission and / or a previous downlink reception. Alternatively, the base station can preset the default beam in the terminal, and the preset default beam can be used in a specific situation.

[0170] If the interval between PUCCH resources allocated to a terminal is narrow, the base station may transmit an RRC message including an indication (e.g., update, switching) of TCI state(s) to the terminal in advance. In this case, the RRC message may include information indicating whether to use a default beam as well as an indication of the TCI state(s). For example, if "the base station wants to transmit an indication of the TCI state(s) for PUCCH resource #2, and the time interval between PUCCH resource #1 and PUCCH resource #2 is narrow," the RRC message including the indication of the TCI state(s) for PUCCH resource #2 may not be transmitted during the time interval between PUCCH resource #1 and PUCCH resource #2. In this case, the base station may transmit an RRC message including the indication of the TCI state(s) for PUCCH resource #2 before PUCCH resource #1. The RRC message may include information indicating TCI state(s) for PUCCH resource #2 and information indicating whether to use default beam(s) (e.g., default TCI state(s)) for PUCCH resource #1. Alternatively, a MAC CE may be used instead of the RRC message. In other words, the base station may transmit a MAC CE including information indicating TCI state(s) for PUCCH resource #2 and information indicating whether to use default beam(s) for PUCCH resource #1.

[0171] FIG. 12 is a conceptual diagram illustrating embodiments of a method for transmitting an RRC message including an indication of TCI state(s) for PUCCH resources.

[0172] Referring to FIG. 12, if the sum of the length of the PDSCH resource to which the RRC message including the indication of the TCI state(s) for PUCCH resource #2 is transmitted and the length of the interval according to timedurationforTCI_PUCCH is greater than or equal to the time interval between PUCCH resource #1 and PUCCH resource #2, the UE may determine that it is impossible to transmit the RRC message including the indication of the TCI state(s) for PUCCH resource #2 in the time interval between PUCCH resource #1 and PUCCH resource #2. In this case, the base station may transmit the RRC message including the indication of the TCI state(s) for PUCCH resource #2 in the PDSCH resource prior to PUCCH resource #1. The RRC message may further include information indicating whether to use the default beam(s) (e.g., the default TCI state(s)) for PUCCH resource #1. Alternatively, MAC CE may be used instead of the RRC message. In other words, the base station may transmit a MAC CE including information indicating TCI state(s) for PUCCH resource #2 and information indicating whether to use a default beam for PUCCH resource #1.

[0173] If the default beam(s) are indicated to be used, the UE may perform PUCCH transmission using the default beam(s) on PUCCH resource #1. If the default beam(s) are indicated to be not used, the UE may perform PUCCH transmission using the beam(s) (e.g., spatial filter, TCI state(s)) used for the most recent uplink transmission on PUCCH resource #1.

[0174] The base station can predict that performance degradation will occur when the default beam according to the proposed method #2 is used in PUCCH resource #1, and can determine that PUCCH reception is impossible in PUCCH resource #1 due to the performance degradation. The base station can instruct PUCCH transmission using the default beam in advance to save power of the terminal. It can be defined that the TCI state(s) for PUCCH resource #1 are not updated regardless of timedurationforTCI_PUCCH. The base station can transmit information to the terminal through signaling indicating that the TCI state(s) for PUCCH resource #1 are not to be updated regardless of timedurationforTCI_PUCCH. Based on the instruction to the base station, the terminal may not update the TCI state(s) for PUCCH resource #1 regardless of timedurationforTCI_PUCCH.

[0175] A base station can transmit update indication information of TCI state(s) to a terminal via signaling. The terminal can receive the update indication information from the base station and update the TCI state(s) for PUCCH resource(s) based on the update indication information. The update indication information can be composed of multiple bits. For example, the update indication information can be composed of 2 bits. The update indication information set to 00 can indicate updating the TCI state(s) starting from the current PUCCH resource or the current PUCCH group. In other words, the update indication information set to 00 can indicate that the update of the TCI state(s) is performed immediately. The update indication information set to 01 can indicate updating the TCI state(s) starting from one PUCCH resource or one PUCCH group. The update indication information set to 10 can indicate updating the TCI state(s) starting from two PUCCH resources or two PUCCH groups. The update indication information set to 11 can indicate an update of the TCI state(s) from 3 PUCCH resources or 3 PUCCH groups onwards.

[0176] Embodiments of the present disclosure may be applied to TCI states (e.g., beam configuration) of other channels (e.g., DL channels and / or UL channels) and / or other signals (e.g., DL signals and / or UL signals) as well as PUCCH. For example, embodiments of the present disclosure may be applied when "an instruction for beam switching exists before a specific channel (e.g., a specific signal), and a change in a transmit beam or receive beam for the specific channel (e.g., the specific signal) is required."

[0177] Embodiments of the present disclosure can be applied to mTRP communication regardless of single DCI and / or multiple DCI. Embodiments of the present disclosure can be applied to both licensed and unlicensed bands. Operations according to the present disclosure can be configured on a panel-by-panel basis (e.g., antenna array). A terminal can report panel-specific time duration information to a base station. Alternatively, the terminal can report common time duration information for panels to a base station. The time duration for each panel can be determined based on the common time duration and a specific offset. The specific offset can be configured on a panel-by-panel basis.

[0178] 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.

[0179] 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.

[0180] 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.

[0181] 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.

[0182] 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.

Claims

1. As a method of UE (user equipment), A step of receiving a message including information indicating one or more transmission configuration indicator (TCI) states for uplink transmission from at least one of a first transmission and reception point (TRP) or a second TRP connected to a base station; and A step of performing the uplink transmission based on the one or more TCI states on the PUCCH resource when the PUCCH (physical uplink control channel) resource is located after the application time of the one or more TCI states, If the PUCCH resource is located before the application time, the uplink transmission on the PUCCH resource is performed based on at least one TCI state different from the one or more TCI states. UE's method.

2. In claim 1, A step of receiving DCI (downlink control information) including downlink scheduling information from at least one TRP; and Further comprising a step of receiving data from at least one TRP on a PDSCH (physical downlink shared channel) resource scheduled by the DCI, The above uplink transmission includes transmission of a hybrid automatic repeat request (HARQ) response to the data. UE's method.

3. In claim 1, The at least one TCI state is a TCI state(s) used for receiving a DCI scheduling a PDSCH resource associated with a HARQ response transmitted on the PUCCH resource. UE's method.

4. In claim 3, The above TCI state(s) are TCI state(s) associated with the CORESET (control resource set) pool from which the DCI is received. UE's method.

5. In claim 1, The at least one TCI state is a TCI state(s) used for uplink transmission prior to reception of the message including information indicating the one or more TCI states. UE's method.

6. In claim 1, The at least one TCI state is a TCI state(s) for a PUCCH set by RRC (radio resource control) signaling of the base station, and the TCI state(s) are set independently from the one or more TCI states. UE's method.

7. In claim 1, wherein at least one of the above TCI states is the TCI state(s) used for the most recent PUCCH transmission. UE's method.

8. In claim 1, The at least one TCI state is a TCI state(s) indicated by a MAC (medium access control) CE (control element) transmitted by the base station, and the TCI state(s) are set independently from the one or more TCI states. UE's method.

9. In claim 1, The at least one TCI state is a TCI state(s) for a CORESET having the lowest ID (index) among a plurality of CORESETs set by the base station. UE's method.

10. In claim 1, The above message further includes information indicating whether default TCI state(s) are used, and if the default TCI state(s) are indicated to be used, the at least one TCI state is the default TCI state(s), and if the default TCI state(s) are indicated to be not used, the at least one TCI state is the TCI state(s) used for the most recent uplink transmission. UE's method.

11. In claim 1, The above application time is the sum of the processing time of the above message and the time required to apply one or more of the above TCI states. UE's method.

12. In claim 1, The above message is received on PDSCH or PDCCH. UE's method.

13. As a method of base station, A step of transmitting a message including information indicating one or more transmission configuration indicator (TCI) states for uplink transmission to a UE (user equipment) through at least one of a first TRP (transmission and reception point) or a second TRP; and A step of receiving the uplink transmission from the UE based on the one or more TCI states on the PUCCH resource, when the PUCCH (physical uplink control channel) resource is located after the application time of the one or more TCI states, If the PUCCH resource is located before the application time, the reception operation for the uplink transmission on the PUCCH resource is performed based on at least one TCI state different from the one or more TCI states. Method of base station.

14. In claim 13, The at least one TCI state is a TCI state(s) used for transmission of downlink control information (DCI) that schedules a physical downlink shared channel (PDSCH) resource associated with a hybrid automatic repeat request (HARQ) response received on the PUCCH resource. Method of base station.

15. In claim 13, The at least one TCI state is a TCI state(s) used for receiving operation for uplink transmission prior to transmission of the message including information indicating the one or more TCI states. Method of base station.

16. In claim 13, The at least one TCI state is a TCI state(s) for a PUCCH set by RRC (radio resource control) signaling of the base station, and the TCI state(s) are set independently from the one or more TCI states. Method of base station.

17. In claim 13, wherein at least one of the above TCI states is the TCI state(s) used for reception operation for the most recent PUCCH transmission. Method of base station.

18. In claim 13, The at least one TCI state is a TCI state(s) indicated by a MAC (medium access control) CE (control element) transmitted by the base station, and the TCI state(s) are set independently from the one or more TCI states. Method of base station.

19. In claim 13, The at least one TCI state is a TCI state(s) for a CORESET having the lowest ID (index) among a plurality of CORESETs (control resource sets) set by the base station. Method of base station.

20. In claim 13, The above message further includes information indicating whether default TCI state(s) are used, and if the default TCI state(s) are indicated to be used, the at least one TCI state is the default TCI state(s), and if the default TCI state(s) are indicated to be not used, the at least one TCI state is the TCI state(s) used for a reception operation for the most recent uplink transmission. Method of base station.

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