Method and apparatus for uplink transmission in communication system

Abstract

A method by a UE according to an embodiment of the present disclosure may comprise the steps of: receiving first DCI from a first TRP; when the received first DCI is in a format indicating UL transmission and a first field included in the first DCI indicates UL transmission to a second TRP, identifying whether switching between sTRPs is supported; performing TRP switching to the second TRP from the first TRP supporting the switching between the sTRPs; and transmitting a PUSCH on the basis of a TCI state corresponding to the second TRP.

Description

Uplink transmission method and device in a communication system

[0001] The present disclosure relates to improved communication technologies, and more particularly to uplink transmission technologies.

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

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

[0004] Meanwhile, in a communication system, transmission and reception points (TRPs) can be used to expand communication coverage, resolve problems of communication impossibility and / or potential channel blocking in shadow areas, and provide spatial diversity effects.

[0005] In a communication system utilizing TRPs, a terminal may communicate with a single TRP or multiple TRPs. There may be instances where a terminal must communicate with multiple TRPs while communicating with a single TRP, or where a terminal must communicate with one TRP while communicating with multiple TRPs, or where a terminal must communicate with another TRP while communicating with one TRP.

[0006] In situations like the above, a terminal may need a method to provide procedures and control information that can determine which TRP to maintain a connection with or to switch a connection to.

[0007] The purpose of the present disclosure to solve the above problems is to provide a method and device for a terminal to switch between transmission and reception points (TRPs) in a communication system.

[0008] According to a first embodiment of the present disclosure for achieving the above object, a method of a user equipment (UE) may include: receiving first downlink control information (DCI) from a first transmission and reception point (TRP); checking whether switching between single TRPs (sTRPs) is supported when the received first DCI is in a format indicating uplink (UL) transmission and a first field included in the first DCI indicates UL transmission to a second TRP; performing TRP switching from the first TRP supporting the switching between sTRPs to the second TRP; and transmitting a physical uplink shared channel (PUSCH) based on a transmission configuration indication (TCI) state corresponding to the second TRP.

[0009] The above first DCI is the first TCI state (1) for UL transmission. st joint / UL TCI state) and the second TCI state (2 nd The second PUSCH transmitted to the second TRP may further include a TCI state indication field indicating a joint / UL TCI state, and the second PUSCH transmitted to the second TRP may be transmitted based on either the first TCI state or the second TCI state.

[0010] The above TCI status may be determined by a TCI status indication field included in the second DCI most recently received among the DCIs for downlink (DL) transmission received before receiving the first DCI.

[0011] The above TCI status indication field indicates the first TCI state (1) for UL transmission. stjoint / UL TCI state) and the second TCI state (2 nd (joint / UL TCI state) may be included.

[0012] The method may further include a step of transmitting the PUSCH to the first TRP based on a TCI state for UL transmission included in a radio resource control (RRC) message for receiving the first DCI when the first field indicates UL transmission to the second TRP and switching between the sTRPs is not supported.

[0013] The method may further include a step of transmitting the PUSCH to the first TRP based on a TCI state for UL transmission included in the second DCI most recently received among DCIs received before receiving the first DCI, when the first field indicates UL transmission to the second TRP and switching between the sTRPs is not supported.

[0014] The method may further include a step of transmitting physical uplink shared channels (PUSCHs) to each of the first TRP and the second TRP based on TCI states corresponding to each of the first TRP and the second TRP, when the received first DCI is in a format indicating uplink (UL) transmission and the first field indicates UL transmission to both the first TRP and the second TRP.

[0015] The first TCI state corresponding to the first TRP is the first TCI state (1) included in the first DCI. st joint / UL TCI state) or second TCI state (2 ndjoint / UL TCI state), and the second TCI state corresponding to the second TRP may be a TCI state different from the TCI state applied to the first TRP among the first TCI state or the second TCI state.

[0016] The first TCI state corresponding to the first TRP is the first TCI state (1) included in the second DCI most recently received among the DCIs received before the first DCI is received. st joint / UL TCI state) or second TCI state (2 nd joint / UL TCI state), and the second TCI state corresponding to the second TRP may be a TCI state different from the TCI state applied to the first TRP among the first TCI state or the second TCI state.

[0017] The first field is a sounding reference signal (SRS) resource set indicator field consisting of 2 bits, and when the 2 bits of the SRS resource indicator set indicate "00", it indicates transmission of the PUSCH to the currently communicating TRP, and when the 2 bits of the SRS resource indicator set indicate "01", it indicates transmission of the PUSCH to the second TRP, and when the 2 bits of the SRS resource indicator set are either "10" or "11", it can indicate transmission of the PUSCHs to the first TRP and the second TRP.

[0018] A user equipment (UE) according to one embodiment of the present disclosure comprises at least one processor, wherein the UE:

[0019] A method for receiving first downlink control information (DCI) from a first transmission and reception point (TRP); determining whether single TRP (sTRP) switching is supported when the received first DCI is in a format indicating uplink (UL) transmission and a first field included in the first DCI indicates UL transmission to a second TRP; performing TRP switching from the first TRP supporting the sTRP switching to the second TRP; and causing a physical uplink shared channel (PUSCH) to be transmitted based on a transmission configuration indication (TCI) state corresponding to the second TRP.

[0020] The above first DCI is the first TCI state (1) for UL transmission. st joint / UL TCI state) and the second TCI state (2 nd The second PUSCH transmitted to the second TRP may further include a TCI state indication field indicating a joint / UL TCI state, and the second PUSCH transmitted to the second TRP may be transmitted based on either the first TCI state or the second TCI state.

[0021] The above TCI status may be determined by a TCI status indication field included in the second DCI most recently received among the DCIs for downlink (DL) transmission received before receiving the first DCI.

[0022] The above TCI status indication field indicates the first TCI state (1) for UL transmission. st joint / UL TCI state) and the second TCI state (2 nd (joint / UL TCI state) may be included.

[0023] The at least one processor is configured such that the UE:

[0024] The first field may further cause the PUSCH to be transmitted to the first TRP based on a TCI state for UL transmission included in a radio resource control (RRC) message for receiving the first DCI when the first field indicates UL transmission to the second TRP and switching between the sTRPs is not supported.

[0025] The at least one processor is configured such that the UE:

[0026] If the first field indicates UL transmission to the second TRP and switching between the sTRPs is not supported, the PUSCH may be further caused to be transmitted to the first TRP based on a TCI state for UL transmission included in the second DCI most recently received among the DCIs received before receiving the first DCI.

[0027] The at least one processor is configured such that the UE:

[0028] If the received first DCI is in a format indicating uplink (UL) transmission, and the first field indicates UL transmission to both the first TRP and the second TRP, it may further cause physical uplink shared channels (PUSCHs) to be transmitted to each of the first TRP and the second TRP based on TCI states corresponding to each of the first TRP and the second TRP.

[0029] The first TCI state corresponding to the first TRP is the first TCI state (1) included in the first DCI. st joint / UL TCI state) or second TCI state (2 ndjoint / UL TCI state), and the second TCI state corresponding to the second TRP may be a TCI state different from the TCI state applied to the first TRP among the first TCI state or the second TCI state.

[0030] The first TCI state corresponding to the first TRP is the first TCI state (1) included in the second DCI most recently received among the DCIs received before the first DCI is received. st joint / UL TCI state) or second TCI state (2 nd joint / UL TCI state), and the second TCI state corresponding to the second TRP may be a TCI state different from the TCI state applied to the first TRP among the first TCI state or the second TCI state.

[0031] The first field is a sounding reference signal (SRS) resource set indicator field consisting of 2 bits, and when the 2 bits of the SRS resource indicator set indicate "00", it indicates transmission of the PUSCH to the currently communicating TRP, and when the 2 bits of the SRS resource indicator set indicate "01", it indicates transmission of the PUSCH to the second TRP, and when the 2 bits of the SRS resource indicator set are either "10" or "11", it can indicate transmission of the PUSCHs to the first TRP and the second TRP.

[0032] The present disclosure provides a procedure for dynamically switching to a single TRP (sTRP) based on DCI for uplink transmission while a UE is communicating with multiple TRPs (mTRPs). In addition, the present disclosure provides a procedure for dynamically switching to another TRP while communicating with an sTRP, and in this case, the present disclosure provides a procedure for switching from one TRP to another and an operation in the UE. If switching from one TRP to another is not supported, the present disclosure provides a method for performing uplink transmission to an existing TRP to eliminate ambiguity. Therefore, the present disclosure has the advantage of eliminating ambiguity in TRP switching operations by providing whether TRP switching is allowed in an sTRP environment and an operation method of the UE based on whether it is allowed.

[0033] Figure 1 is a conceptual diagram illustrating a first embodiment of a communication system.

[0034] Figure 2 is a block diagram illustrating a first embodiment of a communication node constituting a communication system.

[0035] Figure 3 is a block diagram illustrating a first embodiment of communication nodes performing communication.

[0036] Figure 4a is a block diagram illustrating a first embodiment of a transmission path.

[0037] Figure 4b is a block diagram illustrating a first embodiment of a receiving path.

[0038] Figure 5 is a conceptual diagram illustrating a first embodiment of a system frame in a communication system.

[0039] Figure 6 is a conceptual diagram illustrating a first embodiment of a subframe in a communication system.

[0040] Figure 7 is a conceptual diagram illustrating a first embodiment of a slot in a communication system.

[0041] Figure 8 is a conceptual diagram illustrating a first embodiment of time-frequency resources in a communication system.

[0042] Figure 9a is a conceptual diagram illustrating a case where a UE communicates with two different TRPs through each link.

[0043] FIG. 9b is a conceptual diagram illustrating a first embodiment in which a UE communicates with one of two different TRPs via a communication link formed with the TRP.

[0044] FIG. 9c is a conceptual diagram illustrating a second embodiment in which a UE communicates with one of two different TRPs via a communication link formed with the TRP.

[0045] FIG. 9d is a conceptual diagram illustrating a first embodiment in which a UE communicates with one of three different TRPs via a communication link formed with the TRP.

[0046] Figure 10 is a flowchart for explaining the dynamic switching operation between mTRP and sTRP.

[0047] Fig. 11 is a flowchart of the operation of a UE according to the first method when switching from mTRP to sTRP and then switching to sTRP is possible.

[0048] FIG. 12 is a flowchart for explaining a case of transmitting a PUSCH based on reception of control information according to the second method of the present disclosure.

[0049] FIG. 13 is a flowchart for explaining a case of transmitting a PUSCH based on reception of control information according to the third method of the present disclosure.

[0050] FIG. 14 is a flowchart for explaining a case of transmitting a PUSCH based on reception of control information according to the fourth method of the present disclosure.

[0051] 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.

[0052] 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.

[0053] 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.”

[0054] 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.”

[0055] 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.

[0056] 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.

[0057] 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.

[0058] 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.

[0059] 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.

[0060] 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.

[0061] 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 an 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)).

[0062] 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.”

[0063] 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.

[0064] Figure 1 is a conceptual diagram illustrating a first embodiment of a communication system.

[0065] 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.

[0066] A plurality of communication nodes (110 to 130) can support a communication protocol specified in the 3rd generation partnership project (3GPP) standard (e.g., LTE communication protocol, LTE-A communication protocol, NR communication protocol, etc.). 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.

[0067] Figure 2 is a block diagram illustrating a first embodiment of a communication node constituting a communication system.

[0068] 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.

[0069] 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).

[0070] 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).

[0071] 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.

[0072] 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.

[0073] 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.

[0074] 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.

[0075] 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.

[0076] 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.

[0077] Figure 3 is a block diagram illustrating a first embodiment of communication nodes performing communication.

[0078] 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).

[0079] 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.

[0080] 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).

[0081] 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).

[0082] 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).

[0083] 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).

[0084] 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).

[0085] 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.

[0086] FIG. 4a is a block diagram illustrating a first embodiment of a transmission path, and FIG. 4b is a block diagram illustrating a first embodiment of a reception path.

[0087] 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.

[0088] 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.

[0089] 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.

[0090] 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.

[0091] 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.

[0092] 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.

[0093] Figure 5 is a conceptual diagram illustrating a first embodiment of a system frame in a communication system.

[0094] 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.

[0095] 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."

[0096] Figure 6 is a conceptual diagram illustrating a first embodiment of a subframe in a communication system.

[0097] 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.

[0098] Figure 7 is a conceptual diagram illustrating a first embodiment of a slot in a communication system.

[0099] Referring to Figure 7, a single slot may include one or more symbols. A single slot illustrated in Figure 7 may include 14 symbols. The length of a slot may vary depending on the number and length of symbols contained in the slot. Alternatively, the length of a slot may vary depending on the numerology.

[0100] 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.

[0101] Subcarrier spacing 15 kHz 30 kHz 60 kHz 120 kHz 240 kHz 480 kHz OFDM symbol length [μs] 66.733.316.78.34.22.1 CP length [μs] 4.762.381.190.600.300.151 Number of OFDM symbols in ms 142856112224448

[0102] 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.

[0103] 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.

[0104] 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."

[0105] 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.

[0106] 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.

[0107] Figure 8 is a conceptual diagram illustrating a first embodiment of time-frequency resources in a communication system.

[0108] 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.

[0109] 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.

[0110] 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.

[0111] 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.

[0112] 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).

[0113] The search space information may include a coreset identifier (ID) associated with the search space, a period of PDCCH monitoring, and / or an offset. Each of the PDCCH monitoring period and offset may be indicated on a slot-by-slot basis. In addition, the search space information may further include an index of the symbol at which the PDCCH monitoring operation begins.

[0114] 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).

[0115] Meanwhile, a wireless communication system using a Transmission and Reception Point (TRP) can communicate between a multi-TRP (mTRP) and user equipment (UE) using a single-frequency network (SFN) or spatial division multiplexing (SDM) method based on a single downlink control information (DCI) (sDCI). In this case, the communication can include downlink (DL) transmission and uplink (UL) transmission. When the UE performs UL communication between the mTRP and the SFN or SDM method, the transmission can be performed through Simultaneous Transmission across Multi-Panel (STxMP).

[0116] A UE can transmit an uplink, for example, a physical uplink shared channel (PUSCH), in the sDCI-based mTRP SFN / SDM scheme. In this situation, according to the agreement reached in the current 3GPP standard meeting, the UE can dynamically switch from sDCI-based mTRP SFN / SDM-based PUSCH transmission to sTRP PUSCH transmission. However, the agreement reached in the 3GPP standard meeting only mentions that dynamic switching from sDCI-based mTRP SFN / SDM-based PUSCH to sTRP PUSCH is possible, and no specific method has been proposed yet. Therefore, the present disclosure described below will look into how a procedure for dynamic switching of uplink transmission is performed.

[0117] Figure 9a is a conceptual diagram illustrating a case where a UE communicates with two different TRPs through each link.

[0118] Referring to FIG. 9A, a UE (901) and a first TRP (910) and a second TRP (920) are illustrated. The UE (901) may include all or some of the components described above in FIG. 2. Furthermore, the UE (901) may further include components not illustrated in FIG. 2. For example, the UE (901) may further include various sensors, user interfaces, etc. for the convenience of the user.

[0119] The first TRP (910) and / or the second TRP (920) may be a remote node connected to an upper base station. Accordingly, the first TRP (910) and / or the second TRP (920) may include at least some of the configurations illustrated in FIG. 2, and may further include other configurations not illustrated in FIG. 2, for example, a configuration for interfacing with an upper node and / or a configuration for interfacing with another TRP. Each of the first TRP (910) and the second TRP (920) may form a beam through a plurality of antennas, and may form the beam in a specific direction for communication with the UE (901).

[0120] Referring to FIG. 9A, a UE (901) sets up a first TRP (910) and a first communication channel (911), and is expected to communicate with the first TRP (910). Here, the communication channel between the UE (901) and the first TRP (910) may include a physical downlink control channel (PDCCH) and / or a physical downlink shared channel (PDSCH) for downlink. In addition, the communication channel between the UE (901) and the first TRP (910) may include a PUCCH and / or a PUSCH for uplink. Referring to FIG. 9A, a UE (901) sets up a second TRP (920) and a second communication channel (921), and is expected to communicate with the second TRP (920). Here, the communication channel between the UE (901) and the second TRP (920) may include a PDCCH and / or a PDSCH for the downlink, and a PUCCH and / or a PUSCH for the uplink.

[0121] The embodiment of FIG. 9a described above may be an example for an mTRP environment, since the UE (901) is in communication with both the first TRP (910) and the second TRP (920).

[0122] FIG. 9b is a conceptual diagram illustrating a first embodiment in which a UE communicates with one of two different TRPs via a communication link formed with one TRP, FIG. 9c is a conceptual diagram illustrating a second embodiment in which a UE communicates with one of two different TRPs via a communication link formed with one TRP, and FIG. 9d is a conceptual diagram illustrating a first embodiment in which a UE communicates with one of three different TRPs via a communication link formed with one TRP.

[0123] The UE (901) and the first TRP (910) and the second TRP (920) illustrated in FIGS. 9b, 9c, and 9d may all have the same configuration as described in FIG. 9a. Furthermore, FIG. 9d illustrates a configuration further including a third TRP (930). The third TRP (930) may have the same configuration as the first TRP (910) and / or the second TRP (920) illustrated in FIG. 9a.

[0124] First, referring to FIG. 9b, the UE (901) sets up a first communication channel (911) with the first TRP (910) among the first TRP (910) and the second TRP (920). The communication channel between the UE (901) and the first TRP (910) may include a PDCCH and / or a PDSCH for the downlink, as described above, and may include a PUCCH and / or a PUSCH for the uplink. As illustrated in FIG. 9b, the UE (901) is an example in which a communication channel is set up with the first TRP (910), but a communication channel is not set up with the second TRP (920). Therefore, the embodiment of FIG. 9b may be an example in which the UE (901) communicates in an sTRP environment.

[0125] Referring to FIG. 9c, the UE (901) sets up a second communication channel (921) with the second TRP (920) among the first TRP (910) and the second TRP (920). The communication channel between the UE (901) and the second TRP (920) may also include a PDCCH and / or a PDSCH for the downlink, as described above, and may include a PUCCH and / or a PUSCH for the uplink. As illustrated in FIG. 9c, the UE (901) is an example in which a communication channel is set up with the second TRP (920), but a communication channel is not set up with the first TRP (910). Therefore, the embodiment of FIG. 9c may be another example in which the UE (901) communicates in an sTRP environment.

[0126] Referring to FIG. 9d, the UE (901) sets up a third communication channel (931) with the third TRP (930) among the first TRP (910), the second TRP (920), and the third TRP (930). The communication channel between the UE (901) and the third TRP (930) may also include a PDCCH and / or a PDSCH for the downlink, as described above, and may include a PUCCH and / or a PUSCH for the uplink. As illustrated in FIG. 9d, the UE (901) is an example in which a communication channel is set up with the third TRP (930), but no communication channels are set up with the first TRP (910) and the second TRP (920). Therefore, the embodiment of FIG. 9d may also be another example in which the UE (901) communicates in an sTRP environment.

[0127] Figure 10 is a flowchart for explaining the dynamic switching operation between mTRP and sTRP.

[0128] Referring to FIG. 10, a first TRP, a second TRP, and a UE are illustrated. The first TRP, the second TRP, and the UE may have the same configuration as described above in FIGS. 9A to 9D.

[0129] Steps S1000a and S1000b illustrate a situation in which the UE communicates with the first TRP and the second TRP. Accordingly, the UE can perform downlink communication and / or uplink communication with the first TRP and the second TRP.

[0130] In step S1000a, the first TRP can transmit a PDCCH and / or a PDSCH to the UE via a specific beam. Accordingly, the UE can receive the PDCCH and / or the PDSCH via the beam formed by the first TRP. Furthermore, the UE can transmit a PUCCH and / or a PUSCH to the first TRP via a specific beam. Accordingly, the first TRP can receive the PUCCH and / or the PUSCH via the beam formed by the UE.

[0131] In step S1000b, the second TRP can transmit PDCCH and / or PDSCH to the UE via a specific beam. Therefore, the UE can receive PDCCH and / or PDSCH via the beam formed by the second TRP. In addition, the UE can transmit PUCCH and / or PUSCH to the second TRP via a specific beam. Therefore, the second TRP can receive PUCCH and / or PUSCH via the beam formed by the UE.

[0132] In steps S1000a and S1000b, the UE may be in a state of communicating with mTRP since it is an environment in which it communicates with the first TRP and the second TRP.

[0133] In step S1002, the first TRP may transmit switching instruction information to the UE to indicate switching to an sTRP. The switching instruction information to an sTRP may be, for example, information included in DCI. Accordingly, the UE may receive switching instruction information from the first TRP to an sTRP in step S1002. As described above, step S1002 corresponds to a case where the UE is communicating with two different TRPs and thus communicating in an mTRP environment. In addition, since the UE is instructed to switch to an sTRP by the DCI transmitted from the first TRP, it may correspond to a case where a single DCI (sDCI) is used. In other words, step S1002 may correspond to a case where dynamic switching from an mTRP to an sTRP is indicated using sDCI.

[0134] In this disclosure, it is assumed that switching to sTRP is indicated by a sounding reference signal (SRS) resource set indicator included in DCI. The 3GPP standard stipulates that the SRS resource set indicator can be set to 0 bits or 2 bits. Therefore, when the SRS resource set indicator is set to 2 bits in the DCI, the SRS resource set indicator can be set to one of four values: "00", "01", "10", or "11". In this disclosure, it is assumed that switching from mTRP to sTRP is indicated when the SRS resource set indicator is set to "00".

[0135] In step S1004, the UE may perform a switching procedure to sTRP based on the received indication information. At this time, when determining a TRP that can be communicated, the UE may determine the TRP based on a transmission configuration indication (TCI) state activated by MAC-CE and / or indicated by DCI among the TCI states set in a radio resource control (RRC) message.

[0136] The example in Figure 10 illustrates a case where the first TRP is set as an sTRP for communication with the UE. However, the second TRP may also be set as a TRP for communication with the UE. For convenience of explanation, the following description assumes that the first TRP is set as an sTRP for communication with the UE.

[0137] In step S1004, the UE may perform a switching procedure to an sTRP based on the received switching instruction information. Since the example of FIG. 10 assumes that the first TRP is determined as the TRP to communicate with, the sTRP to communicate with may be the first TRP. Therefore, the UE must terminate the connection with the second TRP in step S1004. It should be noted that the example of FIG. 10 does not illustrate the communication termination procedure between the UE and the second TRP.

[0138] In step S1006, the UE can communicate with the first TRP. In other words, the UE can receive PDCCH / PDSCH from the first TRP through a specific beam in the downlink (DL), and can transmit PUCCH / PUSCH to the first TRP through a specific beam in the uplink (UL).

[0139] The procedure described above may be a switching operation from an mTRP environment to an sTRP environment, as illustrated in FIG. 9b, in the situation illustrated in FIG. 9a. In other words, the UE may switch from communicating with the first and second TRPs, as illustrated in FIG. 9a, to communicating only with the first TRP, as illustrated in FIG. 9b, based on a switching instruction set in the DCI to the sTRP.

[0140] The example of Fig. 10 assumes that the first TRP communicates with the UE when switching from an mTRP environment to an sTRP environment. However, a second TRP may also be selected when switching from an mTRP environment to an sTRP environment. If the second TRP is selected when switching from an mTRP environment to an sTRP environment, dynamic switching of TRPs can occur, as in the situation of Fig. 9a, as in the situation of Fig. 9c.

[0141] As another example of dynamic switching of TRPs, the UE may perform TRP dynamic switching, such as in the situation of FIG. 9a, while communicating with the first TRP and the second TRP, and then, based on a switching instruction set in sDCI, communicate with the third TRP, as illustrated in FIG. 9d. If dynamic switching to the third TRP occurs, the UE may perform a connection procedure with the third TRP in step S1004. Furthermore, if dynamic switching to the third TRP occurs, the UE may perform a connection release procedure with the first TRP and the second TRP in step S1004.

[0142] Meanwhile, dynamic switching behavior from sTRP to mTRP may also be possible.

[0143] In step S1006, the UE may be in a state of communicating only with the first TRP. Thereafter, at a specific point in time, for example, in step S1010, the first TRP may instruct the UE to switch TRP to mTRP. Therefore, in step S1010, the UE may receive switching instruction information from the first TRP to mTRP. The switching instruction to mTRP may be indicated by sDCI as described above. In the present disclosure, when the SRS resource set indicator in the DCI is set to 2 bits, any value other than "00" described above may be utilized to instruct switching to mTRP. In other words, when the SRS resource set indicator in the DCI is set to 2 bits, any one of "01", "10", or "11" may be utilized to instruct. This utilization method may be additionally confirmed based on the description below.

[0144] At step S1012, the UE can perform a switching procedure to an mTRP. In other words, it can connect to an additional TRP in addition to the first TRP with which it is currently communicating. The example of FIG. 10 illustrates an additional connection to a second TRP. The example of FIG. 10 is an example, and when dynamically switching TRPs from an sTRP environment to an mTRP environment, an additional connection to a third TRP, rather than the second TRP, may be made.

[0145] In steps S1014a and S1014b, the UE can communicate with the first TRP and the second TRP. In other words, the UE can transmit and receive DL / UL signals and / or data with the first TRP, and can transmit and receive DL / UL signals and / or data with the second TRP.

[0146] Meanwhile, the above description describes dynamic switching from an mTRP environment to an sTRP environment and vice versa. However, it does not mention whether switching to another TRP (sTR) is possible or not after switching from an mTRP environment to an sTRP environment. Furthermore, no specific method is presented for performing dynamic switching of a TRP from an mTRP environment to an sTRP environment. Therefore, the present disclosure described below will describe a method for switching to another sTRP after switching from an mTRP environment to an sTRP environment. In addition, the present disclosure described below will describe an additional method for dynamically switching a TRP from an mTRP to an sTRP environment in addition to the method described above.

[0147] Different definitions may be required for cases where switching to another sTRP is possible after dynamic switching from an mTRP to an sTRP and cases where switching to another sTRP is not possible. Therefore, in this disclosure, we will examine the cases where switching to another sTRP is possible after dynamic switching from an mTRP to an sTRP and the cases where switching to another sTRP is not possible after dynamic switching from an mTRP to an sTRP.

[0148] (1) When switching from mTRP to sTRP and then switching to sTRP is possible

[0149] [Method 1]

[0150] Below, a first method is described in which switching from mTRP to sTRP is possible, followed by switching back to sTRP. Furthermore, in the first method according to the present disclosure described below, an operation in which a UE transmits a PUSCH is described.

[0151] Fig. 11 is a flowchart of the operation of a UE according to the first method when switching from mTRP to sTRP and then switching to sTRP is possible.

[0152] The operation of FIG. 11 may be performed when a UE wishes to transmit a PUSCH while switching from mTRP to sTRP. For convenience of explanation, the following description assumes that the UE communicates with the first TRP, as described in FIG. 10.

[0153] In step S1100, the UE may receive DCI from the first TRP. As shown in FIG. 11, since the UE is considering transmitting a PUSCH, the UE may expect to receive DCI format 0_1 ​​or DCI format 0_2 including uplink transmission control information. The DCI format 0_1 ​​or DCI format 0_2 according to the present disclosure may include a TCI state indication field, an SRS resource set indicator field, two SRS resource indicator (SRI) fields, and two transmit precoding matrix indicator (TPMI) fields.

[0154] If DCI format 0_1 ​​or DCI format 0_2 does not include a TCI status indication field among the above information, the most recently received DCI including a TCI status indication field may be used. The DCI including a TCI status indication field may be, for example, a DCI including UE downlink transmission control information. More specifically, the DCI including a TCI status indication field may use a TCI status indication field included in any one of DCI format 1_1, DCI format 1_2, or DCI format 1_3.

[0155] Additionally, in step S1100, the UE may perform blind decoding on the DCI received from the first TRP. Blind decoding may be performed based on the size of the DCI and the fields included in the DCI. In the present disclosure, since the DCI is assumed to be transmitted via PUSCH, the received DCI may be in DCI format 0_1 ​​or DCI format 0_2.

[0156] In step S1102, the UE can check each field of the decoded DCI, i.e., DCI format 0_1 ​​or DCI format 0_2. The present disclosure stipulates the switching operation from mTRP to sTRP and then back to sTRP. In addition, the present disclosure describes an example in which the switching is indicated using an SRS resource set indicator when switching from sTRP to another sTRP.

[0157] In step S1104, the UE can check whether the SRS resource set indicator has a value of "00". If the SRS resource set indicator has a value of "00", the UE can proceed to step S1106 and transmit the PUSCH based on the first indicated UL TCI state (joint / UL TCI state) among the fields indicating TCI states in the DCI. If the UE does not indicate the value of "00" in the SRS resource set indicator in step S1104, the UE can proceed to step S1110.

[0158] In step S1110, the UE can check whether the SRS resource set indicator has a value of "01". If the SRS resource set indicator has a value of "01", the UE can proceed to step S1112 and transmit a PUSCH based on the second indicated joint / UL TCI state among the fields indicating TCI states in the DCI. If the SRS resource set indicator does not have a value of "01" in step S1110, the SRS resource set indicator may have a value of "10" or "11". Therefore, in the present disclosure, if the SRS resource set indicator has a value of "10" or "11", the UE can proceed to step S1114.

[0159] In step S1114, the UE can transmit PUSCHs to each TRP by switching to mTRP based on the first indicated joint / UL TCI state and the second indicated joint / UL TCI state among the fields indicating TCI states in the DCI, since the SRS resource set indicator has a value of "10" or "11".

[0160] Therefore, when the SRS resource set indicator has a value of "10" or "11", it can correspond to a case in which switching is indicated from sTRP to mTRP.

[0161] Meanwhile, the present disclosure assumes that switching from sTRP to mTRP is indicated when the SRS resource set indicator has a value of "10" or "11." However, if the case in which the SRS resource set indicator indicates "11" is left in a reserved state, the case in which the SRS resource set indicator indicates "11" is ignored and PUSCH transmission may be abandoned.

[0162] [Method 2]

[0163] Below, the switching operation from sTRP to sTRP, sTRP to mTRP, or mTRP to sTRP is described when switching from mTRP to sTRP is possible. In particular, the second method described below describes the operation in which the UE transmits a PUSCH.

[0164] Since the second method of the present disclosure describes an operation of transmitting a PUSCH, it is assumed that DCI format 0_1 ​​and / or DCI format 0_2 have the following two subformats.

[0165] A. If DCI format 0_1 ​​and / or DCI format 0_2 is the first sub-format, either the first option or the second option may be used.

[0166] A1. Some of the information added to or included in DCI format 0_1 ​​and / or DCI format 0_2 when DCI format 0_1 ​​and / or DCI format 0_2 is the first option of the first subformat are as follows:

[0167] TCI state indication field, first SRS resource indicator (SRI), TPMI field

[0168] A2. Some examples of information that is added to or included in DCI Format 0_1 ​​and / or DCI Format 0_2 when DCI Format 0_1 ​​and / or DCI Format 0_2 is the second option of the first subformat are as follows:

[0169] TCI Status Indication field, first SRI, second SRI (defined by reserved bits), first TPMI, and second TPMI (defined by reserved bits) fields

[0170] If the DCI format 0_1 ​​and / or DCI format 0_2 exemplified above is one of the first option or second option of the first subformat, there may be fields that overlap with fields defined in the 3GPP standard, and there may also be fields that need to be newly added. For example, the current 3GPP standard does not define a TCI status indication field in DCI format 0_1 ​​or DCI format 0_2. Therefore, in order to apply the second method of the present disclosure, DCI format 0_1 ​​or DCI format 0_2 may need to be modified to include a TCI status indication field.

[0171] As another example, since DCI format 0_1 ​​or DCI format 0_2 in the current 3GPP standard does not include a TCI status indication field, DCI format 0_1 ​​or DCI format 0_2 can be configured not to include a TCI status indication field. In this case, the TCI status indication field of DCI format 0_1 ​​or DCI format 0_2 can use or be inferred from the TCI status indication field included in any one of DCI format 1_1, DCI format 1_2, or DCI format 1_3, which contains the most recently received downlink control information. This can be understood in the same way as described in the first method. This inferential method can be equally applied when there are other fields not specified in the DCI for UL transmission, although additional fields are required in addition to the TCI status indication field.

[0172] B. Some examples of information according to the second method of the present disclosure, when DCI format 0_1 ​​and / or DCI format 0_2 is the second sub-format, are as follows:

[0173] TCI status indication field, SRS resource set indicator, first SRI, second SRI, first TPMI field, second TPMI field

[0174] The second method of the present disclosure described below describes a procedure for a UE to transmit a PUSCH in uplink when subformats of the DCI format 0_1 ​​and / or DCI format 0_2 described above are used.

[0175] FIG. 12 is a flowchart for explaining a case of transmitting a PUSCH based on reception of control information according to the second method of the present disclosure.

[0176] In describing the flowchart of FIG. 12, the UE may operate when it wishes to transmit a PUSCH. Furthermore, when the UE's operation is described in FIG. 12, a corresponding TRP operation may be performed. For example, when the UE receives a specific DCI, the TRP may generate the corresponding DCI and transmit it to the UE, or receive the corresponding DCI from an upper node and transmit it to the UE. Conversely, when the UE transmits a specific signal, for example, a PUSCH, the TRP may receive the PUSCH. Furthermore, the present disclosure assumes that sDCI is received in an mTRP environment or an sTRP environment.

[0177] In step S1202, the UE can receive sDCI from the TRP and blindly decode the received DCI. Blind decoding can be performed based on the size of the DCI and the fields included in the DCI. The UE can then check the decoded DCI fields. At this time, since the UE intends to transmit a PUSCH, it can expect to receive DCI format 0_1 ​​or DCI format 0_2 from the sTRP.

[0178] If the UE receives DCI format 0_1, the actual received DCI may be one of the first option of the first subformat of DCI format 0_1, the second option of the first subformat of DCI format 0_1, or the second subformat of DCI format 0_1, as described above. If the UE receives DCI format 0_2, the actual received DCI may be one of the first option of the first subformat of DCI format 0_2, the second option of the first subformat of DCI format 0_2, or the second subformat of DCI format 0_2, as described above.

[0179] In explaining Fig. 12, for convenience of explanation, it is assumed that DCI format 0_1 ​​is received. However, even if DCI format 0_2 is received, the UE can perform the same operation as in the case of DCI format 0_1 ​​described below.

[0180] In step S1204, since the UE receives DCI format 0_1, it can check whether the first subformat of the DCI format 0_1 ​​has been received. The first subformat of the DCI format 0_1 ​​can include fields having a first option or a second option as described above. If the first subformat of the DCI format 0_1 ​​has been received as a result of the check in step S1204, the UE can perform step S1206. On the other hand, if the received DCI format 0_1 ​​is not the first subformat as a result of the check in step S1204, the received DCI is the second subformat of the DCI format 0_1. If the DCI format 0_1 ​​has additional subformats in addition to the first and second subformats of the DCI format 0_1, the UE can further include a procedure for checking whether the second subformat of the DCI format 0_1 ​​has been received. However, since the second method of the present disclosure describes a case where only the first subformat and the second subformat of DCI format 0_1 ​​are used, the procedure for checking whether the second subformat of DCI format 0_1 ​​has been received is omitted.

[0181] When proceeding to step S1206, the UE can check whether the current sTRP communication is in progress. If it is mTRP communication, the UE can process DCI failure. This is because the UE operates in an mTRP environment, and the first subformat of DCI format 0_1 ​​for maintaining the current sTRP operation in sTRP is not a normal DCI. Therefore, in step S1204, the first subformat of DCI format 0_1 ​​is received, and if the result of the check in step S1206 indicates that it is an sTRP environment, the routine of FIG. 12 can be terminated. In other words, the UE can give up PUSCH transmission at the PUSCH transmission time.

[0182] If the current status is in communication with sTRP as a result of the inspection at step S1206, the UE can perform step S1208.

[0183] When proceeding to step S1208, since the first subformat of DCI format 0_1 ​​has been received, the UE can transmit a PUSCH to the currently communicating TRP without dynamic switching of the TRP. At this time, the UE can perform PUSCH transmission based on the TCI state corresponding to the RRC setting for reception of the received DCI format 0_1. The TCI state determination method can be determined as follows.

[0184] For example, the first subformat of the received DCI format 0_1 ​​is the first TCI state (e.g. 1 st joint / UL TCI state), second TCI state (e.g. 2 nd joint / UL TCI state). In this way, the first subformat of DCI format 0_1 ​​contains two different TCI states (1 st joint / UL TCI state, 2 ndWhen the UE includes a joint / UL TCI state, the UE may determine the TCI state based on the information indicated by the received RRC message before receiving the first subformat of the DCI format 0_1. For example, if the RRC message indicates to use the first TCI state, the UE may use the first TCI state (1) included in the first subformat of the DCI format 0_1. st PUSCH can be transmitted using joint / UL TCI state.

[0185] As another example, if the RRC message indicates to use the second TCI state, the UE shall use the second TCI state (2) contained in the first subformat of DCI format 0_1. nd PUSCH can be transmitted using joint / UL TCI state.

[0186] Additionally, the first SRI and TPMI fields included in the first subformat of DCI format 0_1 ​​can indicate the SRS resources, precoding information, and number of layers corresponding to the corresponding TCI state. Based on this, the UE can transmit a PUSCH.

[0187] Meanwhile, the case where the process proceeds from step S1204 to step S1210 is when the received DCI 0_1 is the second subformat of DCI format 0_1 ​​as described above. In step S1210, the UE can check whether the SRS resource set field value included in the second subformat of DCI format 0_1 ​​is "00". If the SRS resource set field value included in the second subformat of DCI format 0_1 ​​is "00", the UE can proceed to step S1212, and if the SRS resource set field value included in the second subformat of DCI format 0_1 ​​is not "00", the UE can proceed to step S1220.

[0188] In step S1212, the UE selects the first TCI state (e.g., 1) among the TCI states indicated in the TCI state indication field in the second subformat of the received DCI format 0_1. st The PUSCH can be transmitted based on the joint / UL TCI state. At this time, the first TCI state can be, for example, the TCI state for the currently communicating TRP and PUSCH transmission.

[0189] The case where the UE proceeds from step S1210 to step S1220 is when the SRS resource set field is not "00". Therefore, the UE can check whether the SRS resource set field is "01" in step S1220. If the SRS resource set field is "01", the UE can proceed to step S1222, and if the SRS resource set field is not "01", the UE can proceed to step S1224.

[0190] In step S1222, the UE selects the second TCI state (e.g., 2) among the TCI states indicated in the TCI state indication field in the second subformat of the received DCI format 0_1. nd A PUSCH can be transmitted based on the second TCI state (joint / UL TCI state). At this time, the second TCI state can be, for example, a TRP other than the currently communicating TRP. In other words, TRP dynamic switching can be performed. The TRP dynamic switching procedure is described below with reference to FIGS. 9A to 9D.

[0191] As illustrated in FIG. 9b, if the TRP currently being communicated is the first TRP (910) and the TRP corresponding to the TCI state selected based on the second subformat of the DCI format 0_1 ​​received in step S1222 is the second TRP (920), the UE may transmit a PUSCH to the second TRP (920) as illustrated in FIG. 9c. As another example, if the TRP currently being communicated is the first TRP (910) and the TRP corresponding to the TCI state selected based on the second subformat of the DCI format 0_1 ​​received in step S1222 is the third TRP (930), the UE may transmit a PUSCH to the third TRP (930) as illustrated in FIG. 9d. In other words, step S1222 may be a procedure for performing a dynamic switching operation from an sTRP to another sTRP.

[0192] When proceeding from step S1220 to step S1224, the SRS resource set field is not "00" and not "01". In other words, when proceeding to step S1224, the SRS resource set field may have a value of "10" or "11". In step S1224, the UE selects the first TCI state (e.g., 1) among the TCI states indicated in the TCI state indication field in the second subformat of the received DCI format 0_1. st joint / UL TCI state) and a second TCI state (e.g. 2 nd A PUSCH can be transmitted with two TRPs corresponding to the joint / UL TCI state. In other words, this may be a procedure for dynamic switching of TRPs from sTRP operation to mTRP operation. The TRP dynamic switching procedure of step S1224 is described below with reference to FIGS. 9A to 9D.

[0193] As illustrated in FIG. 9b, the TRP currently being communicated is the first TRP (910), and the first TCI state (e.g., 1) is based on the second sub-format of the DCI format 0_1 ​​received in step S1224. st The TRP corresponding to the joint / UL TCI state is the first TRP (910), and the second TCI state (e.g., 2 nd When the TRP corresponding to the joint / UL TCI state is the second TRP (920), as illustrated in FIG. 9a, the UE can transmit PUSCH to each of the first TRP (910) and the second TRP (920). At this time, the PUSCH transmitted to the first TRP (910) is the first TCI state (e.g., 1 st joint / UL TCI state), and the PUSCH transmitted to the second TRP (920) may be transmitted based on the second TCI state (e.g., 2 nd It can be transmitted based on the joint / UL TCI state.

[0194] In explaining the second method of the present disclosure, it is explained as an example that the case where the SRS resource set indicator is "10" or "11" is interpreted identically. However, if the SRS resource set indicator is "11", the UE does not expect to receive "11" if it is reserved.

[0195] Meanwhile, the overall operation described above assumes that sTRP is maintained while switched from mTRP to sTRP, or that TRP is dynamically switched to another sTRP, or that TRP is dynamically switched from sTRP to mTRP. However, the operation of FIG. 12 can be applied in the same manner even in the mTRP state. Below, the operation of FIG. 12, which is the second method of the present disclosure, is described in the case where it is performed in the mTRP state.

[0196] In step S1202, the UE communicates in an mTRP environment, can receive sDCI from a specific TRP, and can blindly decode the sDCI. The UE can then verify the decoded sDCI. Since the UE intends to transmit via PUSCH, it can expect to receive DCI format 0_1 ​​or DCI format 0_2. The following operations will be considered assuming that DCI format 0_1 ​​is received, as described above.

[0197] In step S1204, the UE can check whether the first subformat of DCI format 0_1 ​​has been received. If the first subformat of DCI format 0_1 ​​has been received as a result of the check in step S1204, the UE can process a DCI failure in step S1206 if it is an mTRP environment.

[0198] If the result of the check in step S1204 is not the first subformat of DCI format 0_1, the UE may proceed to step S1210. The subsequent procedures may be performed in the same manner as described above. For example, if the SRS resource set field is "00" (proceed to "Yes" in step S1210), the UE may select the first TCI state (e.g., 1) among the TCI states indicated in the TCI state indication field in the second subformat of the first DCI format 0_1 ​​in step S1212. st The PUSCH can be transmitted based on the joint / UL TCI state. At this time, the first TCI state can be any of the TRPs communicating in the mTRP environment. For example, the first TCI state can be the TRP that transmitted the sDCI.

[0199] If the SRS resource set field is not "00", in step S1220, the UE may check whether the SRS resource set field is "01". If the SRS resource set is "01", the UE may select the second TCI state (e.g., 2) among the TCI states indicated in the TCI state indication field in the second subformat of the received DCI format 0_1. nd The PUSCH can be transmitted based on the second TCI state (joint / UL TCI state). At this time, the second TCI state can also be any of the TRPs communicating in the mTRP environment. For example, the second TCI state can be a TRP other than the TRP that transmitted the sDCI.

[0200] If the SRS resource set field is neither "00" nor "01", then in step S1224, the UE selects the first TCI state (e.g., 1) among the TCI states indicated in the TCI state indication field in the second subformat of the received DCI format 0_1. st joint / UL TCI state) and a second TCI state (e.g. 2 nd PUSCH can be transmitted with two TRPs corresponding to the joint / UL TCI state.

[0201] [Method 3]

[0202] Below, the switching operation from sTRP to sTRP, sTRP to mTRP, or mTRP to sTRP is described when switching from mTRP to sTRP is possible. In particular, the second method described below describes the operation in which the UE transmits a PUSCH.

[0203] Since the third method of the present disclosure describes an operation of transmitting a PUSCH, it is assumed that DCI format 0_1 ​​and / or DCI format 0_2 have the following two subformats.

[0204] C. If DCI format 0_1 ​​and / or DCI format 0_2 is the third sub-format, either option 1 or option 2 may be used.

[0205] C1. Some of the information added to or included in DCI format 0_1 ​​and / or DCI format 0_2 when DCI format 0_1 ​​and / or DCI format 0_2 is the first option of the third subformat are as follows:

[0206] First SRI, first TPMI field

[0207] C2. Some of the information that is added to or included in DCI Format 0_1 ​​and / or DCI Format 0_2 when DCI Format 0_1 ​​and / or DCI Format 0_2 is the second option of the third subformat are as follows:

[0208] First SRI, first TPMI field, second SRI (defined by reserved bits), second TPMI field (defined by reserved bits)

[0209] If the DCI format 0_1 ​​and / or DCI format 0_2 exemplified above is one of the first or second options of the third subformat, there may be fields that overlap with fields specified in the 3GPP standard, and there may also be fields that need to be newly added. In the case of a DCI field that is not currently specified in the 3GPP standard, the TCI status indication field included in any one of the DCI format 1_1, DCI format 1_2, or DCI format 1_3 that includes the most recently received downlink control information according to the third method of the present disclosure may be used. This method can also be understood in the same form as the contents described in the first method and the second method.

[0210] D. If DCI format 0_1 ​​and / or DCI format 0_2 is the 4th sub-format.

[0211] Some examples of information that is added to or included in DCI Format 0_1 ​​and / or DCI Format 0_2 include:

[0212] TCI status indication field, SRS resource set indicator, first SRI, second SRI, first TPMI field, second TPMI field

[0213] The third method of the present disclosure described below describes a procedure for a UE to transmit a PUSCH in uplink when subformats of the DCI format 0_1 ​​and / or DCI format 0_2 described above are used.

[0214] FIG. 13 is a flowchart for explaining a case of transmitting a PUSCH based on reception of control information according to the third method of the present disclosure.

[0215] The flowchart of Fig. 13 may be an operation for a case where a UE wishes to transmit a PUSCH. In addition, when the operation of the UE is described in Fig. 13, the corresponding operation of the TRP may be performed. For example, when the UE receives a specific DCI, the TRP may generate the corresponding DCI and transmit it to the UE, or receive the corresponding DCI from an upper node and transmit it to the UE. Conversely, when the UE transmits a specific signal, for example, a PUSCH, the TRP may receive the PUSCH. In addition, the present disclosure assumes a case where sDCI is received in an mTRP environment or an sTRP environment.

[0216] In step S1302, the UE can receive sDCI from the TRP and blindly decode the received DCI. Blind decoding can be performed based on the size of the DCI and the fields included in the DCI. The UE can then check the decoded DCI fields. At this time, since the UE intends to transmit a PUSCH, it can expect to receive DCI format 0_1 ​​or DCI format 0_2 from the sTRP.

[0217] If the UE receives DCI format 0_1, the actual received DCI may be one of the first option of the third subformat of DCI format 0_1, the second option of the third subformat of DCI format 0_1, or the second subformat of DCI format 0_1, as described above. If the UE receives DCI format 0_2, the actual received DCI may be one of the first option of the third subformat of DCI format 0_2, the second option of the third subformat of DCI format 0_2, or the fourth subformat of DCI format 0_2, as described above.

[0218] In explaining Fig. 13, for convenience of explanation, it is assumed that DCI format 0_1 ​​is received. However, even if DCI format 0_2 is received, the UE can perform the same operation as in the case of DCI format 0_1 ​​described below.

[0219] In step S1304, since the UE receives DCI format 0_1, it can check whether the third subformat of the DCI format 0_1 ​​has been received. The third subformat of the DCI format 0_1 ​​can include fields having the first option or the second option as described above. If the third subformat of the DCI format 0_1 ​​has been received as a result of the check in step S1304, the UE can perform step S1306. On the other hand, if the received DCI format 0_1 ​​is not the third subformat as a result of the check in step S1304, the received DCI is the fourth subformat of the DCI format 0_1. If the DCI format 0_1 ​​has additional subformats in addition to the third subformat and the fourth subformat of the DCI format 0_1, the UE can further include a procedure for checking whether the fourth subformat of the DCI format 0_1 ​​has been received. However, since the third method of the present disclosure describes a case in which only the third subformat and the fourth subformat of DCI format 0_1 ​​are used, the procedure for checking whether the fourth subformat of DCI format 0_1 ​​has been received is omitted.

[0220] When proceeding to step S1306, the UE can check whether the current sTRP communication is in progress. If it is mTRP communication, the UE can process the DCI failure. This is because the UE operates in an mTRP environment, and the third subformat of the DCI format 0_1 ​​for maintaining the current sTRP operation in sTRP is not a normal DCI. Therefore, in step S1304, the third subformat of the DCI format 0_1 ​​is received, and if the result of the check in step S1306 indicates that it is an sTRP environment, the routine of FIG. 13 can be terminated. In other words, the UE can give up the PUSCH transmission at the PUSCH transmission time.

[0221] If the current status is in communication with sTRP as a result of the inspection at step S1306, the UE can perform step S1308.

[0222] When proceeding to step S1308, since the third subformat of DCI format 0_1 ​​is received, the UE can transmit PUSCH to the currently communicating TRP without dynamic switching of the TRP. At this time, the UE can perform PUSCH transmission based on the TCI state (e.g., joint / DL TCI state) corresponding to the TCI state used in the control resource set (CORESET) for reception of the received DCI format 0_1 ​​or the TCI state (e.g., joint / UL TCI state) associated with the CORESET.

[0223] Additionally, the third subformat of DCI format 0_1 ​​can utilize the first SRI and the first TPMI fields for both the first and second options, as described above. Furthermore, the first SRI and the first TPMI fields can indicate SRS resource precoding information and the number of layers corresponding to the TCI state indicated in the received DCI. Based on this, the UE can transmit a PUSCH.

[0224] Meanwhile, the case where the process proceeds from step S1304 to step S1310 is when the received DCI 0_1 is the fourth subformat of DCI format 0_1 ​​as described above. In step S1310, the UE can check whether the SRS resource set field value included in the fourth subformat of DCI format 0_1 ​​is "00". If the SRS resource set field value included in the second subformat of DCI format 0_1 ​​is "00", the UE can proceed to step S1312, and if the SRS resource set field value included in the second subformat of DCI format 0_1 ​​is not "00", the UE can proceed to step S1320.

[0225] In step S1312, the UE selects the first TCI state (e.g., 1) among the TCI states indicated in the TCI state indication field in the second subformat of the received DCI format 0_1. stThe PUSCH can be transmitted based on the joint / UL TCI state. At this time, the first TCI state can be, for example, the TCI state for the currently communicating TRP and PUSCH transmission.

[0226] The case where the UE proceeds from step S1310 to step S1320 is when the SRS resource set field is not "00". Therefore, the UE can check whether the SRS resource set field is "01" in step S1320. If the SRS resource set field is "01", the UE can proceed to step S1322, and if the SRS resource set field is not "01", the UE can proceed to step S1324.

[0227] In step S1322, the UE selects the second TCI state (e.g., 2) among the TCI states indicated in the TCI state indication field in the fourth subformat of the received DCI format 0_1. nd A PUSCH can be transmitted based on the second TCI state (joint / UL TCI state). At this time, the second TCI state can be, for example, a TRP other than the currently communicating TRP. In other words, TRP dynamic switching can be performed. The TRP dynamic switching procedure is described below with reference to FIGS. 9A to 9D.

[0228] As illustrated in FIG. 9b, if the TRP currently being communicated is the first TRP (910) and the TRP corresponding to the TCI state selected based on the fourth subformat of the DCI format 0_1 ​​received in step S1322 is the second TRP (920), the UE may transmit a PUSCH to the second TRP (920) as illustrated in FIG. 9c. As another example, if the TRP currently being communicated is the first TRP (910) and the TRP corresponding to the TCI state selected based on the second subformat of the DCI format 0_1 ​​received in step S1322 is the third TRP (930), the UE may transmit a PUSCH to the third TRP (930) as illustrated in FIG. 9d. In other words, step S1322 may be a procedure for performing a dynamic switching operation from an sTRP to another sTRP.

[0229] When proceeding from step S1320 to step S1324, the SRS resource set field is not "00" and not "01". In other words, when proceeding to step S1324, the SRS resource set field may have a value of "10" or "11". In step S1324, the UE selects the first TCI state (e.g., 1) among the TCI states indicated in the TCI state indication field in the second subformat of the received DCI format 0_1. st joint / UL TCI state) and a second TCI state (e.g. 2 nd A PUSCH can be transmitted with two TRPs corresponding to the joint / UL TCI state. In other words, this may be a procedure for dynamically switching TRPs from sTRP operation to mTRP operation. The TRP dynamic switching procedure of step S1324 is described below with reference to FIGS. 9A to 9D.

[0230] As illustrated in FIG. 9b, the TRP currently being communicated is the first TRP (910), and the first TCI state (e.g., 1) is based on the second sub-format of the DCI format 0_1 ​​received in step S1324. st The TRP corresponding to the joint / UL TCI state is the first TRP (910), and the second TCI state (e.g., 2 nd When the TRP corresponding to the joint / UL TCI state is the second TRP (920), as illustrated in FIG. 9a, the UE can transmit PUSCH to each of the first TRP (910) and the second TRP (920). At this time, the PUSCH transmitted to the first TRP (910) is the first TCI state (e.g., 1 st joint / UL TCI state), and the PUSCH transmitted to the second TRP (920) may be transmitted based on the second TCI state (e.g., 2 nd It can be transmitted based on the joint / UL TCI state.

[0231] In explaining the third method of the present disclosure, it is explained as an example that the case where the SRS resource set indicator is "10" or "11" is interpreted identically. However, if the SRS resource set indicator is "11", the UE does not expect to receive "11" if it is reserved.

[0232] Meanwhile, the overall operation described above is mainly explained for cases where sTRP is maintained while switched from mTRP to sTRP, or TRP is dynamically switched to another sTRP, or TRP is dynamically switched from sTRP to mTRP. However, the operation of FIG. 13 can be applied in the same manner even in the mTRP state. Below, the operation of FIG. 13, which is the third method of the present disclosure, is described in the case where it is performed in the mTRP state.

[0233] In step S1302, the UE communicates in an mTRP environment, can receive sDCI from a specific TRP, and can blindly decode the sDCI. The UE can then verify the decoded sDCI. Since the UE intends to transmit via PUSCH, it can expect to receive DCI format 0_1 ​​or DCI format 0_2. The following operations will be considered assuming that DCI format 0_1 ​​is received, as described above.

[0234] In step S1304, the UE can check whether the third subformat of DCI format 0_1 ​​has been received. If the first subformat of DCI format 0_1 ​​has been received as a result of the check in step S1304, the UE can process a DCI failure in step S1306 if it is an mTRP environment.

[0235] If the result of the check in step S1304 is not the first subformat of the DCI format 0_1, the UE may proceed to step S1310. The subsequent procedures may be performed in the same manner as described above. For example, if the SRS resource set field is "00" (proceed to "Yes" in step S1310), the UE may select the first TCI state (e.g., 1) among the TCI states indicated in the TCI state indication field in the second subformat of the first DCI format 0_1 ​​in step S1312. st The PUSCH can be transmitted based on the joint / UL TCI state. At this time, the first TCI state can be any of the TRPs communicating in the mTRP environment. For example, the first TCI state can be the TRP that transmitted the sDCI.

[0236] If the SRS resource set field is not "00", the UE may check whether the SRS resource set field is "01" in step S1320. If the SRS resource set is "01", the UE may select the second TCI state (e.g., 2) among the TCI states indicated in the TCI state indication field in the second subformat of the received DCI format 0_1. nd The PUSCH can be transmitted based on the second TCI state (joint / UL TCI state). At this time, the second TCI state can also be any of the TRPs communicating in the mTRP environment. For example, the second TCI state can be a TRP other than the TRP that transmitted the sDCI.

[0237] If the SRS resource set field is neither "00" nor "01", then in step S1324, the UE selects the first TCI state (e.g., 1) among the TCI states indicated in the TCI state indication field in the 4th subformat of the received DCI format 0_1. st joint / UL TCI state) and a second TCI state (e.g. 2 nd PUSCH can be transmitted with two TRPs corresponding to the joint / UL TCI state.

[0238]

[0239] (2) When switching from mTRP to sTRP and then switching back to sTRP is not possible

[0240] The method described above examined cases where switching from an mTRP to an sTRP and then from an sTRP to another sTRP is possible. However, there may be cases where switching from an mTRP to an sTRP and then from an sTRP to another sTRP is not possible. Below, a case where switching from an mTRP to an sTRP and then from an sTRP to another sTRP is described. Furthermore, this disclosure describes operations when a UE transmits a PUSCH.

[0241] [Method 4]

[0242] As described above, the 3GPP standard stipulates that the SRS resource set indicator can be set to 0 bits or 2 bits. Therefore, the present disclosure assumes that the SRS resource set indicator is set to 2 bits in the DCI. When the SRS resource set indicator is set to 2 bits, the SRS resource set indicator can be set to one of four values: "00", "01", "10", or "11". In the fourth method of the present disclosure, it is assumed that the SRS resource set indicator indicates the following operation.

[0243] 1) The SRS resource set indicator "00" is the first TCI state (e.g., 1) indicated in the received DCI. st It directs the use of joint / UL TCI state).

[0244] 2) SRS resource set indicator "01" is the second TCI state (e.g. 2) among the TCI states indicated in the received DCI. nd It directs the use of joint / UL TCI state).

[0245] 3) SRS resource set indicators "10" and / or "11" are the first TCI state indicated within the DCI (e.g., 1 st joint / UL TCI state) and a second TCI state (e.g. 2 nd Indicates when the joint / UL TCI state is used together. In other words, the SRS resource set indicators "10" and / or "11" can be applied only when the operation is mTRP and not sTRP. If the SRS resource set indicator "11" is reserved, the SRS resource set indicator "11" is not defined and the UE does not expect to receive the SRS resource set indicator "11".

[0246] The DCI according to the fourth method of the present disclosure may include the following fields:

[0247] TCI status indication field, SRS resource set indication field, first SRI field, second SRI field, first TPMI field, second TPMI field

[0248] Among the above fields, fields that are not currently supported by the 3GPP standard can be inferred to be newly added to the DCI or the most recently valid DCI field among the previously received DCI fields is used. Since the present disclosure is for a case where a UE wants to transmit a PUSCH, the DCI exemplified above may be DCI format 0_1 ​​and / or DCI format 0_2. According to the current 3GPP standard, the TCI status indication field is not defined for DCI format 0_1 ​​and / or DCI format 0_2. Therefore, if the current 3GPP standard specification is used as is, the TCI status indication field may use the TCI status indication field included in any one of DCI format 1_1, DCI format 1_2, or DCI format 1_3, which includes the most recently received downlink control information.

[0249] FIG. 14 is a flowchart for explaining a case of transmitting a PUSCH based on reception of control information according to the fourth method of the present disclosure.

[0250] Before describing the operation of FIG. 14, the fourth method of the present disclosure is an embodiment that supports switching from mTRP to sTRP, and a case where switching from sTRP to mTRP is supported. However, the operation may also be an embodiment where switching from sTRP to another sTRP after switching from mTRP to sTRP is not supported. In addition, the present disclosure described below is an embodiment where a UE wishes to transmit a PUSCH.

[0251] At step S1400, the UE may be connected to an sTRP. In other words, as described above, the UE may be communicating with an sTRP after switching from an mTRP to an sTRP.

[0252] In step S1402, the UE may receive DCI from the connected TRP and blindly decode the received DCI. The UE may then verify the decoded DCI field. Blind decoding may be performed based on the size of the DCI and the fields included in the DCI. At this time, since the UE intends to transmit a PUSCH, it may expect to receive DCI format 0_1 ​​or DCI format 0_2 from the sTRP. DCI format 0_1 ​​or DCI format 0_2 may include fields as described above, or may be inferred from other DCI if it does not include them.

[0253] Since the embodiment of Fig. 14 is a flowchart for PUSCH transmission, a case in which a DCI other than DCI for controlling uplink transmission, such as DCI format 0_1 ​​or DCI format 0_2, is received is not considered.

[0254] In step S1404, the UE can check whether the sTRP operation maintenance is indicated based on the SRS resource set indicator among the fields included in DCI format 0_1 ​​or DCI format 0_2. In other words, it can check whether the SRS resource set indicator codepoint described above indicates the sTRP operation maintenance. Whether the SRS resource set indicator codepoint indicates the sTRP operation maintenance may vary depending on the setting value of a previously received RRC message.

[0255] For example, if the setting value of the RRC message is the first TCI state (e.g. 1 stIf the code point of the SRS resource set indicator is "00" indicating the first TCI state when the use of the joint / UL TCI state is indicated, it may be the case that the sTRP operation is maintained. However, if the configuration value of the RRC message indicates the use of the first TCI state, but the code point of the SRS resource set indicator is "00" indicating the second TCI state (e.g., 2 nd If "01" indicates a joint / UL TCI state, it can be interpreted as indicating sTRP switching. Therefore, this case may not be a case of maintaining sTRP operation.

[0256] As another example, the setting value of the RRC message is the second TCI state (e.g. 2 nd If the code point of the SRS resource set indicator is "00" indicating the first TCI state when the RRC message configuration value indicates the use of the second TCI state, and the code point of the SRS resource set indicator is "00" indicating the second TCI state (e.g., 2), it can be interpreted as indicating sTRP switching. On the other hand, if the configuration value of the RRC message indicates the use of the second TCI state, and the code point of the SRS resource set indicator is "00" indicating the second TCI state, it can be interpreted as indicating sTRP switching. nd If "01" indicates joint / UL TCI state, it can be interpreted as indicating maintenance of sTRP operation.

[0257] If the inspection result of step S1404 indicates that sTRP operation should be maintained, the UE may proceed to step S1406 and transmit a PUSCH to the corresponding TRP based on the DCI indication. At this time, the UE may perform the mTRP operation in a manner indicated by the TCI status indication field, the SRS resource set indicator field, and the SRI corresponding to the TCI among the two SRIs and the TPMI corresponding to the TCI among the two TPMI fields included in the received DCI format 0_1 ​​or the received DCI format 0_2.

[0258] On the other hand, if the inspection result of step S1404 does not instruct maintenance of sTRP operation, the UE can proceed to step S1410.

[0259] In step S1410, the UE may check whether switching to mTRP is indicated based on the SRS resource set indicator among the fields included in DCI format 0_1 ​​or DCI format 0_2. In other words, it may be checked whether the SRS resource set indicator codepoint described above indicates switching to mTRP. The case where the SRS resource set indicator codepoint indicates switching to mTRP may be when the SRS resource set indicator codepoint is "10" and / or "11". In other words, the first TCI state (e.g., 1) in the received DCI format 0_1 ​​or DCI format 0_2 st joint / UL TCI state) and a second TCI state (e.g. 2 nd This may be the case when joint / UL TCI state is indicated to be used together.

[0260] If the inspection result of step S1410 indicates that switching to mTRP is instructed, the UE can perform step S1412, and if the inspection result of step S1410 indicates that switching to mTRP is not instructed, the UE can perform step S1430.

[0261] First, let's examine the case where step S1430 is performed. Step S1430 occurs when the result of the check in step S1406 is not sTRP maintenance, and the result of the check in step S1410 is not an indication of switching to mTRP. Therefore, step S1430 may be performed when a switch to sTRP is indicated. However, the fourth method of the present disclosure may support TRP switching from mTRP to sTRP and TRP switching from sTRP to mTRP, but not switching from sTRP to sTRP. Therefore, a UE that needs to transmit a PUSCH may perform step S1430 or omit the PUSCH transmission.

[0262] In step S1430, the UE may operate according to one of two options. If the first option is followed, in step S1430, the UE may transmit the PUSCH to the currently communicating TRP by applying a TCI state corresponding to the RRC configuration. If the second option is followed, in step S1430, the UE may not use the currently received and decoded DCI format 0_1 ​​or DCI format 0_2, but may apply an indication of the DCI format 0_1 ​​or DCI format 0_2 received immediately before. If the UE does not use the DCI format 0_1 ​​or DCI format 0_2 received immediately before, the UE may utilize the TCI state set in the DCI format 1_1, DCI format 1_2, or DCI format 1_3 received immediately before for downlink control.

[0263] Afterwards, the UE may proceed to step S1406 and transmit a PUSCH to the corresponding sTRP based on the indicated information, for example, the indicated information set in the RRC message or set by the previous DCI.

[0264] Next, if the inspection result of step S1410 indicates that DCI format 0_1 ​​or DCI format 0_2 is instructed to switch to mTRP and proceeds to step S1412, the UE can switch to mTRP. For example, as described above in FIG. 9b, this may be the case when the UE is communicating with the first TRP (910) and is simultaneously connected to the first TRP (910) and the second TRP (920) as shown in FIG. 9a. As another example, as described in FIG. 9c, this may be the case when the UE is communicating with the second TRP (290) and is simultaneously connected to the first TRP (910) and the second TRP (920) as shown in FIG. 9a.

[0265] In step S1412, the UE that performed TRP switching from sTRP to mTRP can transmit PUSCH to multiple connected TRPs. In step S1414, the UE can maintain the mTRP state. At this time, the UE can perform the mTRP operation in a manner indicated by the TCI status indication field, the SRS resource set indicator field, two SRIs, and two TPMI fields included in the received DCI format 0_1 ​​or the received DCI format 0_2.

[0266] Afterwards, the UE can receive DCI from one of the mTRPs in step S1416. The UE can then blindly decode the received DCI. Blind decoding can be performed based on the size of the DCI and the fields included in the DCI, as described above. The UE can then verify the decoded DCI fields.

[0267] In step S1418, the UE may check whether switching to sTRP is indicated based on the received DCI, for example, the received DCI format 0_1 ​​or the received DCI format 0_2. The check in step S1418 may be a procedure for checking whether the code point of the SRS resource set indicator included in the DCI format 0_1 ​​or the DCI format 0_2 indicates TRP switching to sTRP, as discussed above. In other words, it may be checked whether the SRS resource set indicator is "00" or "01". If the SRS resource set indicator included in the DCI format 0_1 ​​or the DCI format 0_2 indicates TRP switching to sTRP, the process may proceed to step S1420.

[0268] If the SRS resource set indicator included in DCI format 0_1 ​​or DCI format 0_2 does not indicate TRP switching to sTRP, the UE may proceed to step S1414 as it is a case where the mTRP environment is maintained.

[0269] In step S1420, the UE may perform TRP switching to sTRP based on information in the SRS resource set indicator included in DCI format 0_1 ​​or DCI format 0_2, and then transmit a PUSCH to the connected sTRP. Then, the UE may proceed to step S1400.

[0270] [Method 5]

[0271] The fifth method according to the present disclosure described below is an embodiment for a case where switching from sTRP to another sTRP after switching from mTRP to sTRP is impossible, and two methods are largely presented. First, the fifth method according to the present disclosure is a case where the first subformat and the second subformat for DCI format 0_1 ​​or DCI format 0_2 are utilized as described in the second method above. Second, the fifth method according to the present disclosure is a case where the third subformat and the fourth subformat for DCI format 0_1 ​​or DCI format 0_2 are utilized as described in the third method above.

[0272] <DCI 포맷 0_1 또는 DCI 포맷 0_2에 대한 제1 서브 포맷과 제2 서브 포맷을 활용하는 경우의 실시예>

[0273] An embodiment utilizing the first subformat and the second subformat for DCI format 0_1 ​​or DCI format 0_2 may operate as described above in FIG. 12. However, this may not support TRP switching from one sTRP to another.

[0274] When a UE performing sTRP operation receives DCI of the first subformat among two subformats, the sTRP operation can be maintained without TRP switching. In other words, the UE can maintain the current sTRP when receiving any one of option 1 of the first subformat of DCI format 0_1, option 2 of the first subformat of DCI format 0_1, option 1 of the first subformat of DCI format 0_2, or option 2 of the first subformat of DCI format 0_2. And the UE can transmit PUSCH with the current sTRP. At this time, the indication of the TCI state used for PUSCH transmission can be based on the configuration of an RRC message preset for DCI reception among the TCI states of the received DCI.

[0275] For example, if an RRC message sets the first TCI state for DCI reception, the UE sets the first TCI state included in the received DCI (e.g., 1). st join / UL TCI state) and the second TCI state (e.g. 2 nd The first TCI state among the UL TCI state (join / UL TCI state) can be used for PUSCH transmission. On the other hand, if the RRC message sets the second TCI state for DCI reception, the UE uses the first TCI state included in the received DCI (e.g., 1 st join / UL TCI state) and the second TCI state (e.g. 2 nd The second TCI state among the join / UL TCI state can be used for PUSCH transmission.

[0276] Additionally, the first SRI and TPMI fields included in the received DCI can indicate SRS resources, precoding information, and number of layers corresponding to the corresponding TCI state.

[0277] Meanwhile, if a UE performing sTRP operation receives DCI of the second subformat among the two subformats, the UE may maintain the sTRP operation without TRP switching or perform TRP switching to mTRP. In other words, if the UE receives either the second subformat of DCI format 0_1 ​​or the second subformat of DCI format 0_2, the UE may maintain the current sTRP or perform TRP switching to mTRP.

[0278] As described in the second method above, if the configuration value of the RRC configured for receiving DCI indicates the use of the first TCI state, the UE can expect the SRS resource set indicator included in the received DCI to be in a state that includes '00', '10', or '11'. As another example, if the configuration value of the RRC configured for receiving DCI indicates the use of the second TCI state, the UE can expect the SRS resource set indicator to be in a state that includes '01', '10', or '11'.

[0279] If the SRS resource set indicator is '00' as described in the second method, the first TCI state among the TCI states included in the DCI (e.g. 1) st It indicates the use of the joint / UL TCI state, and if the SRS resource set indicator is '01', the second TCI state (e.g. 2) among the TCI states included in the DCI. nd If the SRS resource set indicator is '10' or '11', it may be an mTRP operation rather than an sTRP operation. As described in the second method, if the SRS resource set indicator '11' is reserved, the UE does not expect to receive '11' as the SRS resource set indicator.

[0280] Meanwhile, if the UE indicates a codepoint other than the codepoint expected by the SRS resource set indicator, the UE may ignore the indication of the codepoint and apply a TCI state (e.g., joint / UL TCI state) based on the configuration in the RRC message configured for DCI reception as described above, or maintain the configuration of the TCI state indicated in the previous DCI. Here, the previous may be the most recently received DCI format 0_1 ​​or DCI format 0_2 among the points in time preceding the current DCI as described above, or any one of the most recently received DCI format 1_1, DCI format DCI format 1_1, or DCI format 1_2 among the points in time preceding the current DCI.

[0281] Meanwhile, when a UE communicating in an mTRP environment wishes to transmit PUSCH, the UE may expect to receive a second subformat for DCI format 0_1 ​​or DCI format 0_2. Accordingly, the UE may attempt blind decoding based on the received DCI size and field definitions during decoding attempt. In addition, the UE may perform sTRP or mTRP operation in a manner indicated by the TCI status indication field, SRS resource set indication field, first SRI, second SRI, first TPMI field, and second TPMI field included in the decoded DCI.

[0282] For example, if the SRS resource set indicator in the received DCI is '00', the UE selects the first TCI state (e.g., 1) among the TCI states indicated by the field indicating the TCI state in the DCI. st PUSCH can be transmitted based on the joint / UL TCI state (Example 1 of sTRP transmission). As another example, if the SRS resource set indicator field in the received DCI is '01', the second TCI state (e.g., 2) among the TCI states indicated by the field indicating the TCI state in the corresponding DCI is transmitted.nd PUSCH can be transmitted based on the joint / UL TCI state (Example 2 of sTRP transmission).

[0283] As another example, if the SRS resource set indicator is '10' or '11', the UE will enter the first TCI state (e.g. 1 st joint / UL TCI state) and a second TCI state (e.g. 2 nd PUSCH can be transmitted with two TRPs based on the joint / UL TCI state.

[0284] As described in the second method, if the SRS resource set indicator '11' is reserved, the UE does not expect to receive DCI with the SRS resource set indicator set to '11'.

[0285] <DCI 포맷 0_1 또는 DCI 포맷 0_2에 대한 제3 서브 포맷과 제3 서브 포맷을 활용하는 경우의 실시예>

[0286] An embodiment utilizing the third and fourth subformats for DCI format 0_1 ​​or DCI format 0_2 may operate as described above in FIG. 13. However, this may not support TRP switching from one sTRP to another.

[0287] When a UE performing sTRP operation receives DCI of the third subformat among two subformats, the sTRP operation can be maintained without TRP switching. In other words, the UE can maintain the current sTRP when receiving any one of option 1 of the third subformat of DCI format 0_1, option 2 of the third subformat of DCI format 0_1, option 1 of the third subformat of DCI format 0_2, or option 2 of the third subformat of DCI format 0_2. And the UE can transmit PUSCH with the current sTRP. At this time, the TCI state used for PUSCH transmission can use a TCI state corresponding to a TCI state used in CORESET for DCI reception (e.g., joint / DL TCI state) or associated with a TCI state used in CORESET.

[0288] The third subformat of DCI format 0_1 ​​can utilize the first SRI and the first TPMI fields for both the first and second options, as described above. Furthermore, the first SRI and the first TPMI fields can indicate SRS resource precoding information and the number of layers corresponding to the TCI state indicated in the received DCI. Based on this, the UE can transmit a PUSCH.

[0289] Meanwhile, if a UE performing sTRP operation receives DCI of subformat 4 among two subformats, that is, if the UE receives either DCI format 0_1 ​​of the fourth subformat or DCI format 0_2 of the fourth subformat, the sTRP operation can be maintained without TRP switching, or switched to mTRP operation.

[0290] For example, if the configuration value of the RRC message configured for receiving DCI indicates the first TCI state (e.g., 1st TCI state), the UE may expect the SRS resource set indicator in the received DCI to be '00', '10', or '11'. As another example, if the configuration value of the RRC message configured for receiving DCI indicates the second TCI state (e.g., 2nd TCI state), the UE may expect the SRS resource set indicator in the received DCI to be '01', '10', or '11'.

[0291] As described in the third method, if the SRS resource set indicator is '00', the first TCI state (e.g., 1) among the TCI states in the received DCI is used. st If it indicates joint / UL TCI state,

[0292] If the SRS resource set indicator is '01', the second TCI state (e.g., 2) is selected among the TCI states indicated in the DCI among the TCI states in the received DCI. nd If the SRS resource set indicator is '10' or '11', and if it is mTRP operation rather than sTRP, the first TCI state (e.g. 1) in the received DCI is st joint / UL TCI state) and a second TCI state (e.g. 2 nd This may be the case when both the joint / UL TCI state are used. In this case, if the SRS resource set indicator '11' is reserved, the UE does not expect to receive DCI with the SRS resource set indicator set to '11'.

[0293] Additionally, if the SRS resource set indicator indicates a code point other than the expected code point, the indication of the code point may be ignored, and the TCI state corresponding to the RRC configuration set for DCI reception (e.g., joint / UL TCI state) may be applied as described in the third method, or the setting of the TCI state indicated in the previous DCI may be maintained.

[0294] On the other hand, a UE performing an mTRP operation expects to receive the fourth subformat of DCI format 0_1 ​​or the fourth subformat of DCI format 0_1. Therefore, the UE can perform blind decoding according to the DCI size and field definition when coding the received DCI. And the UE can perform an sTRP or mTRP operation in a manner indicated by the TCI status indication field, the SRS resource set indication field, the first SRI, the second SRI, the first TPMI field, and the second TPMI field in the DCI.

[0295] As described in the third method above, the UE can determine the TCI state based on the SRS resource set indicator included in the received DCI.

[0296] For example, a UE that receives DCI of the 4th subformat of DCI format 0_1 ​​or DCI of the 4th subformat of DCI format 0_1, if the SRS resource set indicator field is '00', the UE enters the first TCI state (e.g., 1) among the TCI states within the corresponding DCI. st PUSCH can be transmitted based on the joint / UL TCI state.

[0297] As another example, a UE that receives DCI in the 4th subformat of DCI format 0_1 ​​or the 4th subformat of DCI format 0_1, if the SRS resource set indicator field is '01', the UE enters the second TCI state (e.g., 2) among the TCI states within that DCI. ndPUSCH can be transmitted based on the joint / UL TCI state.

[0298] As another example, a UE that receives a DCI in the 4th subformat of DCI format 0_1 ​​or the 4th subformat of DCI format 0_1, if the SRS resource set indicator field is '10' or '11', the UE shall enter the first TCI state (e.g., 1) within that DCI. st joint / UL TCI state) and a second TCI state (e.g. 2 nd PUSCHs can be transmitted to each TRP based on the joint / UL TCI state.

[0299] At this time, if the SRS resource set indicator '11' is reserved as described in the third method, the UE does not expect to receive '11' as the SRS resource set indicator.

[0300] 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.

[0301] 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.

[0302] 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.

[0303] 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.

[0304] 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. In the method of user equipment (UE), A step of receiving first downlink control information (DCI) from a first transmission and reception point (TRP); A step of confirming whether switching between single TRPs (sTRPs) is supported when the received first DCI is in a format indicating uplink (UL) transmission and a first field included in the first DCI indicates UL transmission with a second TRP; A step of performing TRP switching from the first TRP to the second TRP supporting switching between the above sTRPs; and A step of transmitting a physical uplink shared channel (PUSCH) based on a transmission configuration indication (TCI) status corresponding to the second TRP, UE's method.

2. In claim 1, The above first DCI is the first TCI state (1) for UL transmission. st joint / UL TCI state) and the second TCI state (2 nd It further includes a TCI state indication field indicating the joint / UL TCI state, The second PUSCH transmitted to the second TRP is transmitted based on either the first TCI state or the second TCI state. UE's method.

3. In claim 1, The above TCI status is determined by the TCI status indication field included in the second DCI most recently received among the DCIs for downlink (DL) transmission received before the reception of the first DCI. UE's method.

4. In claim 3, The above TCI status indication field indicates the first TCI state (1) for UL transmission. st joint / UL TCI state) and the second TCI state (2 nd Including joint / UL TCI state) UE's method.

5. In claim 1, Further comprising a step of transmitting the PUSCH to the first TRP based on a TCI state for UL transmission included in a radio resource control (RRC) message for receiving the first DCI when the first field indicates UL transmission to the second TRP and switching between the sTRPs is not supported. UE's method.

6. In claim 1, Further comprising a step of transmitting the PUSCH to the first TRP based on a TCI state for UL transmission included in a second DCI most recently received among DCIs received before receiving the first DCI, when the first field indicates UL transmission to the second TRP and switching between the sTRPs is not supported. UE's method.

7. In claim 1, The method further comprises the step of transmitting physical uplink shared channels (PUSCHs) to each of the first TRP and the second TRP based on TCI states corresponding to each of the first TRP and the second TRP, when the received first DCI is in a format indicating uplink (UL) transmission and the first field indicates UL transmission to both the first TRP and the second TRP. UE's method.

8. In claim 7, The first TCI state corresponding to the first TRP is the first TCI state (1) included in the first DCI. st joint / UL TCI state) or second TCI state (2 nd is in one of the TCI states (joint / UL TCI state), and The second TCI state corresponding to the second TRP is a TCI state different from the TCI state applied to the first TRP among the first TCI state or the second TCI state. UE's method.

9. In claim 7, The first TCI state corresponding to the first TRP is the first TCI state (1) included in the second DCI most recently received among the DCIs received before the first DCI is received. st joint / UL TCI state) or second TCI state (2 nd is in one of the TCI states (joint / UL TCI state), and The second TCI state corresponding to the second TRP is a TCI state different from the TCI state applied to the first TRP among the first TCI state or the second TCI state. UE's method.

10. In claim 1, The above first field is a sounding reference signal (SRS) resource set indicator field consisting of 2 bits, If the 2 bits of the above SRS resource indicator set indicate "00", the PUSCH transmission is indicated with the currently communicating TRP, If the 2 bits of the above SRS resource indicator set indicate "01", the PUSCH transmission is indicated with the second TRP, and The two bits of the above SRS resource indicator set, either “10” or “11”, indicate transmission of the PUSCHs with the first TRP and the second TRP. UE's method.

11. In user equipment (UE), comprising at least one processor, wherein said at least one processor comprises: Receive first downlink control information (DCI) from a first transmission and reception point (TRP); If the received first DCI is in a format indicating uplink (UL) transmission and the first field included in the first DCI indicates UL transmission with a second TRP, it is confirmed whether switching between single TRPs (sTRPs) is supported; Performing TRP switching from the first TRP to the second TRP supporting switching between the above sTRPs; and Causing to transmit a physical uplink shared channel (PUSCH) based on a transmission configuration indication (TCI) status corresponding to the second TRP. UE.

12. In claim 11, The above first DCI is the first TCI state (1) for UL transmission. st joint / UL TCI state) and the second TCI state (2 nd It further includes a TCI state indication field indicating the joint / UL TCI state, The second PUSCH transmitted to the second TRP is transmitted based on either the first TCI state or the second TCI state. UE.

13. In claim 11, The above TCI status is determined by the TCI status indication field included in the second DCI most recently received among the DCIs for downlink (DL) transmission received before the reception of the first DCI. UE.

14. In claim 13, The above TCI status indication field indicates the first TCI state (1) for UL transmission. st joint / UL TCI state) and the second TCI state (2 nd Including joint / UL TCI state) UE.

15. In claim 11, At least one processor of the UE: Further causing the PUSCH to be transmitted to the first TRP based on a TCI state for UL transmission included in a radio resource control (RRC) message for receiving the first DCI if the first field indicates UL transmission to the second TRP and switching between the sTRPs is not supported. UE.

16. In claim 11, At least one processor of the UE: Further causing the PUSCH to be transmitted with the first TRP based on a TCI state for UL transmission included in a second DCI most recently received among DCIs received before receiving the first DCI, if the first field indicates UL transmission with the second TRP and switching between the sTRPs is not supported. UE.

17. In claim 11, At least one processor of the UE: If the received first DCI is in a format indicating uplink (UL) transmission, and the first field indicates UL transmission to both the first TRP and the second TRP, further causing physical uplink shared channels (PUSCHs) to be transmitted to each of the first TRP and the second TRP based on TCI states corresponding to each of the first TRP and the second TRP, UE.

18. In claim 17, The first TCI state corresponding to the first TRP is the first TCI state (1) included in the first DCI. st joint / UL TCI state) or second TCI state (2 nd is in one of the TCI states (joint / UL TCI state), and The second TCI state corresponding to the second TRP is a TCI state different from the TCI state applied to the first TRP among the first TCI state or the second TCI state. UE.

19. In claim 17, The first TCI state corresponding to the first TRP is the first TCI state (1) included in the second DCI most recently received among the DCIs received before the first DCI is received. st joint / UL TCI state) or second TCI state (2 nd is in one of the TCI states (joint / UL TCI state), and The second TCI state corresponding to the second TRP is a TCI state different from the TCI state applied to the first TRP among the first TCI state or the second TCI state. UE.

20. In claim 11, The above first field is a sounding reference signal (SRS) resource set indicator field consisting of 2 bits, If the 2 bits of the above SRS resource indicator set indicate "00", the PUSCH transmission is indicated with the currently communicating TRP, If the 2 bits of the above SRS resource indicator set indicate "01", the PUSCH transmission is indicated with the second TRP, and The two bits of the above SRS resource indicator set, either “10” or “11”, indicate transmission of the PUSCHs with the first TRP and the second TRP. UE.

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