Method and apparatus for uplink communication in a communication system supporting multiple panels

Abstract

A method and apparatus for uplink communication in a communication system supporting multiple panels are disclosed. The method by a terminal includes receiving a first SSB from a first TRP, determining a first DL timing based on the first SSB, receiving a second SSB from a second TRP, determining a second DL timing based on the second SSB, receiving a PDCCH order from the first TRP, and, if a first information element included in the PDCCH order indicates the second SSB or the second TRP, transmitting an RA preamble to the second TRP based on the second DL timing.

Description

[Technical Field]

[0001] The present disclosure relates to communication techniques, and more particularly to uplink communication techniques for terminals having multiple panels. [Background technology]

[0002] To handle the rapidly increasing volume of wireless data, communication systems (e.g., new radio (NR) communication systems) that use higher frequency bands (e.g., frequency bands above 6 GHz) than the frequency bands (e.g., frequency bands below 6 GHz) of LTE (long term evolution) (or LTE-A) are being considered. NR communication systems can support frequency bands above 6 GHz as well as frequency bands below 6 GHz, and can support a wider variety of communication services and scenarios than LTE communication systems. For example, usage scenarios for NR communication systems include enhanced Mobile BroadBand (eMBB), Ultra Reliable Low Latency Communication (URLLC), massive Machine Type Communication (mMTC), etc. Communication technologies are needed to meet the requirements of eMBB, URLLC, and mMTC.

[0003] Meanwhile, various wireless communication technologies have been developed with the advancement of information and communication technology. Wireless communication technologies include LTE communication technology and NR communication technology defined by the 3GPP (3rd Generation Partnership Project) standard. LTE communication technology can be one of the 4th Generation (4G) wireless communication technologies, and NR communication technology can be one of the 5th Generation (5G) wireless communication technologies. To handle the rapidly increasing amount of wireless data after the commercialization of 4G communication systems (e.g., communication systems supporting LTE communication technology), 5G communication systems (e.g., communication systems supporting NR communication technology) that use not only the frequency band of the 4G communication system (e.g., frequency bands below 6 GHz) but also frequency bands higher than the frequency band of the 4G communication system (e.g., frequency bands above 6 GHz) are being considered. 5G communication systems can support eMBB, URLLC, mMTC, and / or time sensitive communication (TSC). In particular, mMTC, URLLC, and / or TSC can be applied in Internet of Things (IoT) scenarios. A single communication network (e.g., a single communication system) can support all or some of the above scenarios. The mMTC scenario can meet the IMT (International Mobile Telecommunication)-2020 requirements by using NB (narrowband)-IoT and LTE-MTC. Technology development is necessary to meet the requirements of the URLLC scenario. Summary of the Invention [Problem to be solved by the invention]

[0004] SUMMARY OF THE INVENTION In order to solve the above problems, an object of the present disclosure is to provide a method and apparatus for uplink communication of a terminal having multiple panels in a communication system. [Means for solving the problem]

[0005] To achieve the above object, a method of a terminal according to an embodiment of the present disclosure includes the steps of receiving a first SSB from a first TRP, determining a first DL timing based on the first SSB, receiving a second SSB from a second TRP, determining a second DL timing based on the second SSB, receiving a PDCCH order from the first TRP, and, if a first information element included in the PDCCH order indicates the second SSB or the second TRP, transmitting an RA preamble to the second TRP based on the second DL timing.

[0006] The method for the terminal may further include transmitting information indicating that the terminal supports two DL timings to at least one of the first TRP or the second TRP.

[0007] The first DL timing may be different from the second DL timing, and the difference between the first DL timing and the second DL timing may be less than or greater than the CP.

[0008] A first TA between the terminal and the first TRP may be determined based on the first DL timing, and a second TA between the terminal and the second TRP may be determined based on the second DL timing.

[0009] The first information element may be information for selecting an SSB index indicating the second SSB or a PCI indicating the second TRP.

[0010] The terminal method may further include receiving a MAC CE from the second TRP in response to the RA preamble, and deriving at least one of a first TA between the terminal and the first TRP, a second TA between the terminal and the second TRP, or a TAC based on information elements included in the MAC CE, and the first TA and the second TA may belong to different TAGs.

[0011] When uplink transmission to which the first TA or the second TA is applied is performed, the TAG identifier referenced to determine the first TA or the second TA can be derived from the spatial relationship information or TCI referenced by the uplink transmission.

[0012] The terminal may have two or more panels, and a first communication between the terminal and the first TRP may be performed on a first panel of the two or more panels, and a second communication between the terminal and the second TRP may be performed on a second panel of the two or more panels.

[0013] A base station method according to an embodiment of the present disclosure for achieving the above object includes the steps of transmitting a first SSB through a first TRP associated with the base station, transmitting a second SSB through a second TRP associated with the base station, transmitting a PDCCH order to a terminal through the first TRP, and receiving an RA preamble from the terminal through the second TRP indicated by the PDCCH order.

[0014] The base station method may further include receiving information indicating that the terminal supports two DL timings from the terminal via at least one of the first TRP or the second TRP.

[0015] A first DL timing may be determined by the terminal based on the first SSB, and a second DL timing may be determined by the terminal based on the second SSB, the first DL timing may differ from the second DL timing, and the difference between the first DL timing and the second DL timing may be less than or equal to CP or may exceed the CP.

[0016] A first TA between the terminal and the first TRP may be determined based on the first DL timing, and a second TA between the terminal and the second TRP may be determined based on the second DL timing.

[0017] The PDCCH order may include a first information element, and the first information element may be information for selecting an SSB index indicating the second SSB or a PCI indicating the second TRP.

[0018] The base station method may further include transmitting a MAC CE through the second TRP in response to the RA preamble, and information elements included in the MAC CE may be used to derive at least one of a first TA between the terminal and the first TRP, a second TA between the terminal and the second TRP, or a TAC, and the first TA and the second TA may belong to different TAGs.

[0019] When uplink transmission to which the first TA or the second TA is applied is performed, the TAG identifier referenced to determine the first TA or the second TA can be derived from the spatial relationship information or TCI referenced by the uplink transmission.

[0020] To achieve the above object, a terminal according to an embodiment of the present disclosure includes at least one processor, wherein the at least one processor causes the terminal to receive a first SSB from a first TRP, determine a first DL timing based on the first SSB, receive a second SSB from a second TRP, determine a second DL timing based on the second SSB, receive a PDCCH order from the first TRP, and, if a first information element included in the PDCCH order indicates the second SSB or the second TRP, transmit an RA preamble to the second TRP based on the second DL timing.

[0021] The at least one processor may further cause the terminal to transmit information indicating that the terminal supports two DL timings to at least one of the first TRP or the second TRP.

[0022] The first DL timing may be different from the second DL timing, and the difference between the first DL timing and the second DL timing may be less than or greater than the CP.

[0023] The first information element may be information for selecting an SSB index indicating the second SSB or a PCI indicating the second TRP.

[0024] The at least one processor may further cause the terminal to receive a MAC CE from the second TRP in response to the RA preamble, and to derive at least one of a first TA between the terminal and the first TRP, a second TA between the terminal and the second TRP, or a TAC based on information elements included in the MAC CE, and the first TA and the second TA may belong to different TAGs. [Effects of the Invention]

[0025] According to the present disclosure, a terminal can communicate with multiple transmission and reception points (TRPs). The terminal can determine a first downlink (DL) timing based on a first synchronization signal block (SSB) received from a first TRP, and can determine a second downlink (DL) timing based on a second SSB received from a second TRP. A first timing advance (TA) between the terminal and the first TRP can be determined based on the first DL timing, and a second TA between the terminal and the second TRP can be determined based on the second DL timing. The terminal can manage two TAs, and in this case, communication performance between the terminal and multiple TRPs can be improved. [Brief explanation of the drawings]

[0026] [Figure 1] 1 is a conceptual diagram illustrating a first embodiment of a communication system.

[0027] [Figure 2]1 is a block diagram illustrating a first embodiment of a communication node that constitutes a communication system.

[0028] [Figure 3] FIG. 1 is a conceptual diagram illustrating a first embodiment of SFN transmission.

[0029] [Figure 4] FIG. 10 is a conceptual diagram illustrating a second embodiment of SFN transmission.

[0030] [Figure 5] FIG. 1 is a conceptual diagram illustrating a first embodiment of SDM transmission.

[0031] [Figure 6] FIG. 10 is a conceptual diagram illustrating a second embodiment of SDM transmission.

[0032] [Figure 7] FIG. 1 is a conceptual diagram illustrating a first embodiment of an event that occurs in STxMP transmission.

[0033] [Figure 8] FIG. 1 is a conceptual diagram illustrating a first embodiment of a timing alignment method.

[0034] [Figure 9] FIG. 10 is a conceptual diagram illustrating a second embodiment of the timing alignment method.

[0035] [Figure 10] FIG. 10 is a conceptual diagram illustrating a third embodiment of the timing alignment method.

[0036] [Figure 11] FIG. 10 is a conceptual diagram illustrating a fourth embodiment of the timing alignment method.

[0037] [Figure 12] FIG. 1 is a conceptual diagram illustrating a first embodiment of a single-entry PHR MAC CE.

[0038] [Figure 13] FIG. 1 is a conceptual diagram illustrating a first embodiment of a multi-entry PHR MAC CE.

[0039] [Figure 14] FIG. 10 is a conceptual diagram illustrating a second embodiment of a multi-entry PHR MAC CE.

[0040] [Figure 15] FIG. 1 is a conceptual diagram illustrating a first embodiment of an improved single-entry PHR MAC CE.

[0041] [Figure 16a] FIG. 1 is a conceptual diagram illustrating a first embodiment of an improved multi-entry PHR MAC CE.

[0042] [Figure 16b] FIG. 1 is a conceptual diagram illustrating a first embodiment of an improved multi-entry PHR MAC CE.

[0043] [Figure 17a] FIG. 10 is a conceptual diagram illustrating a second embodiment of an improved multi-entry PHR MAC CE.

[0044] [Figure 17b] FIG. 10 is a conceptual diagram illustrating a second embodiment of an improved multi-entry PHR MAC CE.

[0045] [Figure 18] FIG. 1 is a conceptual diagram illustrating a first embodiment of an improved single-entry PHR MAC CE for multiple TRPs.

[0046] [Figure 19] FIG. 1 is a conceptual diagram illustrating a first embodiment of an improved multi-entry PHR MAC CE for multiple TRPs.

[0047] [Figure 20]FIG. 10 is a conceptual diagram illustrating a second embodiment of an improved multi-entry PHR MAC CE for multiple TRPs.

[0048] [Figure 21] FIG. 1 is a conceptual diagram illustrating a first embodiment of SRS configuration based on the Rel-15 NR technical standard.

[0049] [Figure 22] FIG. 1 is a conceptual diagram illustrating a first embodiment of SRS configuration based on the Rel-16 NR technical standard.

[0050] [Figure 23] FIG. 1 is a conceptual diagram illustrating a first embodiment of SRS configuration based on the Rel-17 NR technical standard.

[0051] [Figure 24] FIG. 1 is a conceptual diagram illustrating a first embodiment of SRS configuration taking into account multiple Tx panels.

[0052] [Figure 25] FIG. 1 is a conceptual diagram illustrating a first embodiment of SRS configuration considering multiple TRPs and multiple Tx panels. DETAILED DESCRIPTION OF THE INVENTION

[0053] While the present disclosure can be modified in various ways and can have various embodiments, specific embodiments will be illustrated in the drawings and described in detail, but it should be understood that this is not intended to limit the disclosure to the specific embodiments, and that all modifications, equivalents, and alternatives within the spirit and technical scope of the present disclosure are included.

[0054] Terms such as "first," "second," etc. may be used to describe various components, but the components should not be limited by these terms. These terms are used only to distinguish one component from another. For example, a first component may be designated as a second component, and similarly, a second component may be designated as a first component, without departing from the scope of the present disclosure. The term "and / or" includes a combination of multiple associated listed items or any of multiple associated listed items.

[0055] In the embodiments of the present disclosure, "at least one of A and B" may mean "at least one of A or B" or "at least one of a combination of one or more of A and B." Also, in the embodiments of the present disclosure, "one or more of A and B" may mean "one or more of A or B" or "one or more of a combination of one or more of A and B."

[0056] When a component is said to be "coupled" or "connected" to another component, it should be understood that it may be directly coupled or connected to the other component, but that there may be other components in between. Conversely, when a component is said to be "directly coupled" or "directly connected" to another component, it should be understood that there are no other components in between.

[0057] The terms used in this disclosure are merely used to describe specific embodiments and are not intended to limit the present disclosure. Singular expressions include plural expressions unless the context clearly dictates otherwise. In this disclosure, terms such as "comprise" or "have" are intended to specify the presence of features, numbers, steps, operations, components, parts, or combinations thereof described in the specification, and should be understood not to preclude the possibility of the presence or addition of one or more other features, numbers, steps, operations, components, parts, or combinations thereof.

[0058] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. Terms as defined in commonly used dictionaries should be interpreted as having a meaning consistent with the meaning they have in the context of the relevant art, and should not be interpreted in an idealized or overly formal sense unless expressly defined in this disclosure.

[0059] Hereinafter, preferred embodiments of the present disclosure will be described in more detail with reference to the accompanying drawings. In describing the present disclosure, the same reference numerals will be used to refer to the same components in the drawings, and redundant descriptions of the same components will be omitted, in order to facilitate overall understanding.

[0060] A communication system to which an embodiment of the present disclosure is applied will be described. The communication system to which an embodiment of the present disclosure is applied is not limited to the content of the following description, and the embodiment of the present disclosure may be applied to various communication systems. Here, the communication system may be used interchangeably with a communication network.

[0061] In embodiments, "an operation (e.g., a transmission operation) is configured" may mean that "configuration information (e.g., information elements, parameters) for the corresponding operation" and / or "information instructing the performance of the corresponding operation" is signaled. "An information element (e.g., a parameter) is configured" may mean that the corresponding information element is signaled. The signaling may be at least one of system information (SI) signaling (e.g., transmission of a master information block (MIB), a system information block (SIB), and / or an SI message), RRC signaling (e.g., transmission of an RRC message, an RRC parameter, and / or an upper layer parameter), MAC control element (CE) signaling (e.g., transmission of a MAC message and / or a MAC CE), or PHY signaling (e.g., transmission of downlink control information (DCI), uplink control information (UCI), and / or sidelink control information (SCI)).

[0062] FIG. 1 is a conceptual diagram illustrating a first embodiment of a communication system.

[0063] 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, and 130-6. 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), and a mobility management entity (MME)). When 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.

[0064] The plurality of communication nodes 110 to 130 can support communication protocols (eg, LTE communication protocol, LTE-A communication protocol, NR communication protocol, etc.) defined in the 3GPP (3rd generation partnership project) standard. The plurality of communication nodes 110 to 130 may support CDMA (code division multiple access) technology, WCDMA (wideband CDMA) technology, TDMA (time division multiple access) technology, FDMA (frequency division multiple access) technology, OFDM (orthogonal frequency division multiplexing) technology, Filtered OFDM technology, CP (cyclic prefix)-OFDM technology, DFT-s-OFDM (discrete Fourier transform-spread-OFDM) technology, OFDMA (orthogonal frequency division multiple access) technology, SC (single carrier)-FDMA technology, NOMA (non-orthogonal multiple access) technology, GFDM (generalized frequency division multiplexing) technology, FBMC (filter bank multi-carrier) technology, UFMC (universal filtered multi-carrier) technology, SDMA (Space Division Multiple Access) technology, etc. Each of the plurality of communication nodes may have the following structure.

[0065] FIG. 2 is a block diagram illustrating a first embodiment of a communication node that constitutes a communication system.

[0066] 2, a communication node 200 may include at least one processor 210, a memory 220, and a transceiver 230 that is connected to a network to perform communication. 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 is connected to a bus 270 to perform communication.

[0067] However, each component included in the communication node 200 may be connected through a separate interface or separate bus centered around the processor 210, rather than through the common bus 270. For example, the processor 210 may be connected to at least one of the memory 220, the transceiver 230, the input interface device 240, the output interface device 250, and the storage device 260 through a dedicated interface.

[0068] 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 on which the methods according to the embodiments of the present disclosure are performed. The memory 220 and the storage device 260 may each be composed of at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory 220 may be composed of at least one of a read-only memory (ROM) and a random access memory (RAM).

[0069] 1, the communication system 100 may include multiple base stations 110-1, 110-2, 110-3, 120-1, and 120-2, and multiple terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6. The first base station 110-1, the second base station 110-2, and the third base station 110-3 may each form a macro cell. The fourth base station 120-1 and the fifth base station 120-2 may each form a small cell. The fourth base station 120-1, the third terminal 130-3, and the fourth terminal 130-4 may belong to 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 belong 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 belong within the cell coverage of the third base station 110-3. The first terminal 130-1 may belong within the cell coverage of the fourth base station 120-1. The sixth terminal 130-6 may belong within the cell coverage of the fifth base station 120-2.

[0070] Here, the multiple base stations 110-1, 110-2, 110-3, 120-1, and 120-2 may be referred to as NodeBs (NBs), evolved NodeBs (eNBs), gNBs, advanced base stations (ABSs), high reliability-base stations (HR-BSs), base transceiver stations (BTSs), radio base stations, radio transceivers, access points, access nodes, radio access stations (RASs), mobile multihop relay-base stations (MMR-BSs), relay stations (RSs), advanced relay stations (ARSs), high reliability-relay stations (HR-RSs), home NodeBs (HNBs), home eNodeBs (HeNBs), road side units (RSUs), radio remote heads (RRHs), transmission points (TPs), transmission and reception points (TRPs), etc.

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

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

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

[0074] The first base station 110-1, the second base station 110-2, and the third base station 110-3 can each transmit signals to the fourth terminal 130-4 based on the CoMP scheme, and the fourth terminal 130-4 can receive signals 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. The multiple base stations 110-1, 110-2, 110-3, 120-1, and 120-2 can each transmit and receive signals to and from terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6 within their own cell coverage based on the CA scheme. The first base station 110-1, the second base station 110-2, and the third base station 110-3 can each control D2D between the fourth terminal 130-4 and the fifth terminal 130-5, and the fourth terminal 130-4 and the fifth terminal 130-5 can perform D2D under the control of the second base station 110-2 and the third base station 110-3, respectively.

[0075] Next, a method of operation of a communication node in a communication system will be described. Even when a method (e.g., signal transmission or reception) performed by a first communication node among the communication nodes is described, a corresponding second communication node can perform a method (e.g., signal reception or transmission) corresponding to the method performed by the first communication node. In other words, when the operation of a terminal is described, the corresponding base station can perform an operation corresponding to the operation of the terminal. Conversely, when the operation of a base station is described, the corresponding terminal can perform an operation corresponding to the operation of the base station.

[0076] A communication system can support various wireless communication technologies. Wireless communication technologies can include LTE (long term evolution) communication technology and NR (new radio) communication technology defined by the 3GPP (3rd Generation Partnership Project) standard. LTE communication technology can be one of the wireless communication technologies of 4G (4th Generation) wireless communication technologies. NR communication technology can be one of the wireless communication technologies of 5G (5th Generation) wireless communication technologies.

[0077] To handle the rapidly increasing amount of wireless data following the commercialization of 4G communication systems (e.g., communication systems supporting LTE communication technology), 5G communication systems (e.g., communication systems supporting NR communication technology) that use not only 4G communication system frequency bands (e.g., frequency bands below 6 GHz) but also higher frequency bands (e.g., frequency bands above 6 GHz) than the 4G communication system frequency bands are being considered. 5G communication systems can support enhanced Mobile Broadband (eMBB), Ultra Reliable Low Latency Communication (URLLC), massive Machine Type Communication (mMTC), and / or time sensitive communication (TSC). In particular, mMTC, URLLC, and / or TSC can be applied in Internet of Things (IoT) scenarios. A single communication network (e.g., a single communication system) can support all or some of the above scenarios. The mMTC scenario can use narrowband (NB)-IoT and LTE-MTC to meet International Mobile Telecommunication (IMT)-2020 requirements. Technology development is needed to meet the requirements of the URLLC scenario.

[0078] To reduce the data error rate, a low modulation and coding scheme (MCS) level (e.g., a low MCS index) can be applied. To prevent an increase in the size of a field (e.g., an information field) indicated by downlink control information (DCI), the most frequently used MCS(es) can be selected. Then, to apply a low MCS, a repetitive transmission operation can be supported. Because quadrature phase shift keying (QPSK) has the lowest modulation rate, this can result in a further reduction in the code rate. In particular, because transmission power is limited in uplink (UL) transmission, the repetitive transmission operation can be performed in the time domain rather than the frequency domain.

[0079] Enhanced Mobile BroadBand (eMBB) traffic and Ultra-Reliable and Low Latency Communication (URLLC) traffic can use a lower MCS for different purposes. eMBB traffic can use a lower MCS to extend reach. On the other hand, URLLC traffic can use a lower MCS to reduce latency and achieve a low error rate. Due to different requirements, eMBB traffic can be transmitted repeatedly even if latency occurs, while URLLC traffic can be transmitted using a new MCS (e.g., a lower MCS) rather than repeated transmission. The new MCS can be set by an RRC message and / or DCI.

[0080] To support repeated transmission for eMBB traffic in the time domain, physical uplink shared channel (PUSCH) repetition (e.g., PUSCH repetition type A) may be introduced. In this case, the PUSCH allocated on a slot-by-slot basis may be repeatedly transmitted. To extend reach, time resources may be allocated to multiple slots. When PUSCH repetition type A is used, the time resources may be configured by an RRC message and / or DCI. The number of PUSCH repetitions may be indicated by an RRC message, and the time resource in which the PUSCH is transmitted in the first slot may be indicated by a DCI (e.g., a type 2 configured grant (CG) or dynamic grant) or an RRC message (e.g., a type 1 CG). In this disclosure, the number of repetitions may refer to the number of repeated transmissions or the number of transmissions.

[0081] Repeated transmission of URLLC traffic may cause delays, so repeated transmission of URLLC traffic may not be appropriate. However, if a sufficiently low MCS is used, the delay in decoding URLLC traffic may be reduced. That is, if a sufficiently low MCS is used, the number of resource elements (REs) to which URLLC traffic is mapped may increase, and the base station (e.g., the base station decoder) must wait until it receives all the REs. In this case, the delay in decoding URLLC traffic may be reduced.

[0082] On the other hand, when a PUSCH with a somewhat higher MCS is repeatedly transmitted, the base station may perform decoding operations using only some of the REs. Therefore, the earliest successful decoding point in a PUSCH repeated transmission (e.g., a PUSCH repeated transmission with a somewhat higher MCS) may be earlier than the earliest successful decoding point in a non-repeated PUSCH transmission (e.g., a PUSCH transmission with a lower MCS). When PUSCH repetition type A is used, unnecessary delay may occur, and PUSCH repetition type B may be introduced to reduce the delay time for repeated transmission. When PUSCH repetition type B is used, PUSCHs allocated in mini-slot units may be repeatedly transmitted. When PUSCH repetition type B is used, time resources may be configured by an RRC message and / or DCI. The combination of the reference time resource and the number of repeated transmissions of a PUSCH instance may be indicated by DCI (e.g., type 2 CG and / or dynamic grant) or an RRC message (e.g., type 1 CG).

[0083] To control the transmit power of an SRS resource indicated by an SRS (sounding reference signal) resource indicator (SRI), the base station can estimate the path attenuation for each SRS resource. The base station can control the transmit power for the SRS resource(s) using the DCI. The transmit power of the SRS resource(s) can be controlled based on the estimated path attenuation. The DCI can be a scheduling DCI (e.g., DCI format 0_0, DCI format 0_1, DCI format 0_2, DCI format 1_0, DCI format 1_1, or DCI format 1_2) or a group common (GC)-DCI (e.g., DCI format 2_2 or DCI format 2_3). The DCI can include a field indicating a transmit power control (TPC) command, and the TPC command can be used to control the transmit power of the terminal. For example, the transmit power of the terminal can be increased or decreased based on the TPC command included in the DCI. To determine the transmit power of the PUSCH, the terminal may consider a value obtained based on path attenuation, a value according to the TPC command included in the DCI, and / or the PUSCH bandwidth indicated by the DCI.

[0084] The base station can configure two or more sets for the terminal using higher layer signaling. The terminal can receive configuration information for two or more sets from the base station. Elements constituting each of the two or more sets can be transmit power parameter(s) and can be instructed to suit different scenarios (e.g., URLLC scenario, eMBB scenario). The terminal can receive a scheduling DCI or activating DCI allocating PUSCH resources from the base station, and the scheduling DCI or activating DCI can indicate a set for analyzing the transmit power parameter(s). If the sets of transmit power parameter(s) are different, the magnitude of the increase or decrease in transmit power instructed by the same TPC command can be different.

[0085] When Type 1 CG or Type 2 CG is used, the transmit power may be determined based on DCI format 2_3 for the SRI associated with the PUSCH instance. When Type 2 CG is used, the activation DCI may indicate a set of transmit power parameter(s) to be applied to a PUSCH occasion. A PUSCH occasion may refer to a PUSCH instance. The terminal may obtain a TPC command for the SRI by receiving a GC (group common)-DCI, parse the TPC command to match the set of transmit power parameter(s) indicated by the base station, and derive the transmit power to be applied to the PUSCH instance based on the parse result.

[0086] In dynamically scheduled PUSCH transmission, the terminal can derive the transmit power to be applied to the PUSCH instance based on a combination of the GC-DCI and the scheduling DCI. The terminal can confirm the TCP command of the SRI by receiving the GC-DCI and store the confirmed TCP command. In dynamically scheduled PUSCH transmission, a set of transmit power parameter(s) and / or TPC command to be applied to the PUSCH occasion can be indicated by the scheduling DCI. The terminal can derive the transmit power to be applied to the PUSCH instance based on the transmit power of the SRI associated with the PUSCH instance.

[0087] HARQ-ACK repeat transmission can be indicated (or configured) by higher layer signaling for each physical uplink control channel (PUCCH) format. The number of repeat transmissions for PUCCH format i can be configured independently, where i can be 1, 3, or 4. A UE can repeatedly transmit a PUCCH format in a slot. In this case, the PUCCH format can be transmitted using the same time resource in each slot.

[0088] Uplink control information (UCI) types may be classified according to the type of information included in the UCI. The UCI may include at least one of a scheduling request (SR), reference signal received power (L1-RSRP), HARQ-ACK, or channel state information (CSI). In some embodiments, the terms UCI and UCI type may be used interchangeably. In a repeated UCI transmission operation, only one UCI type may be transmitted. To support this operation, the priority of UCI types may be defined in a technical standard. One UCI type may be selected, and a PUCCH including the selected UCI type may be repeatedly transmitted. In this case, the UE may assume that other UCI types will not be transmitted before the transmission of the corresponding UCI type is completed. To support this operation, the base station may instruct the UE to transmit UCI (e.g., SR or HARQ-ACK) after the PUCCH transmission is completed. The waiting time for the corresponding UCI transmission may be long, which may act as a constraint on the BS's scheduling.

[0089] When "it is indicated that HARQ-ACK should be transmitted in the same slot (or the same subslot)" or "when PUCCH time resources indicated by DCI and / or RRC messages allocating PDSCHs (physical downlink shared channels) overlap," the UE may generate a HARQ codebook so that the HARQ-ACK bits are transmitted in one PUCCH (e.g., one PUCCH time resource). In the HARQ codebook, HARQ-ACK bits may be arranged in an order defined by the technical standard. Information bits may be generated by the above-described operations. The UE may generate coded bits by performing a coding operation.

[0090] A Reed-Muller code or a polar code may be used in the encoding operation. The code rate applied in the encoding operation may be indicated by higher layer signaling. For example, in the PUCCH format, one value may be the code rate and may be indicated to the UE.

[0091] One codeword can be mapped to one PUCCH. In a PUCCH repeated transmission operation, one UCI type can be generated by the codeword. When a PUCCH is transmitted once, information bits of one UCI type or two or more UCI types can be concatenated, and the UE can generate one codeword by performing the same coding operation on the information bits. When a Reed-Muller code or a polar code is used, performing a soft combining operation can be difficult in practice. Therefore, even when a PUCCH is repeatedly transmitted, the same codeword can be transmitted, and the base station can perform a chase combining operation on the same codeword. A coded bit or codeword can refer to a bit string in which multiple code blocks are concatenated. A modulation operation can be performed on the codeword, and the result of the modulation operation can be mapped to an RE.

[0092] Meanwhile, UCIs of the same type may be considered as different information. The same UCI type considered as different information may be mapped. For example, UCIs may be generated to support traffic with different priorities. UCIs supporting eMBB traffic (e.g., SR or HARQ-ACK) may be considered as information distinct from UCIs supporting URLLC traffic (e.g., SR or HARQ-ACK). In this case, even if UCI types are the same, they may be distinguished as different information.

[0093] The coded UCI may be mapped to a PUCCH. The same pre-processing scheme (e.g., spatial information, spatial relation) may be maintained during PUCCH transmission. Alternatively, different pre-processing schemes may be allowed for each PUCCH depending on base station signaling (e.g., RRC signaling).

[0094] To support URLLC traffic, it is preferable for a terminal to perform frequent reception operations on DL (downlink) resources and / or frequent transmission operations on UL (uplink) resources. In a time division duplex (TDD) system, a terminal can operate based on a half duplex scheme. Therefore, the support time for DL ​​traffic and / or UL traffic can increase depending on the slot pattern. On the other hand, in a frequency division duplex (FDD) system, a terminal can utilize both DL and UL resources. Therefore, the problems described above in TDD systems may not occur in FDD systems. An FDD system can use two or more carriers. When two or more serving cells are configured for a terminal in a TDD system, the terminal can utilize both DL and UL resources.

[0095] In a communication system including at least one carrier to which FDD is applied (hereinafter referred to as "FDD carrier"), there may be no problem with terminal delay time. In a communication system including only carrier(s) to which TDD is applied (hereinafter referred to as "TDD carrier(s)"), there may be a problem with terminal delay time. To solve the above problem, slots in the TDD carriers may be configured according to different patterns.

[0096] Transmission of eMBB traffic and / or URLLC traffic can be supported in at least one of a licensed spectrum or an unlicensed spectrum. Carrier(s) belonging to a licensed spectrum can be used independently. Carrier(s) belonging to an unlicensed spectrum can be used independently. Alternatively, depending on the base station configuration, carrier(s) belonging to a licensed spectrum and carrier(s) belonging to an unlicensed spectrum can all be used based on a frequency aggregation scheme.

[0097] In some embodiments, two or more terminals can receive data from one or more TRPs and transmit data to one or more TRPs. It may be assumed that one base station or one server performs management and / or scheduling operations for one or more TRPs among multiple TRPs. The TRPs may be directly connected, or the TRPs may be connected through a base station. The above connection may be via an Xn interface or a radio interface (e.g., a 3GPP NR interface).

[0098] Shadow areas may occur between areas supported by TRPs. Therefore, TRPs can eliminate shadow areas through cooperative transmission. Cooperative transmission can be performed for terminals located between TRPs. Even if shadow areas do not occur, the quality of the wireless link can be improved by installing more TRPs (or base stations) to transmit and receive more data.

[0099] Depending on the cooperative transmission and reception of TRPs, communication methods can be classified into dynamic point selection (DPS) and joint transmission (JT). For a specific set of physical resource blocks (PRBs), DPS is a method of receiving data through one TRP, while JT is a method of receiving data through two or more TRPs. Dynamic point blanking (DPB) is a type of JT. When DPB is used, a terminal can block data from some TRPs and receive data from the remaining TRPs. JT can be classified into coherent JP and noncoherent JP. Depending on whether or not a coherent combining operation is performed on the signals received from the TRPs, coherent JP or noncoherent JP can be used.

[0100] Depending on the latency and / or traffic capacity of the backhaul to which the base station or TRP is connected, the TRP may be able to participate in cooperative transmission and / or cooperative reception in real time. Alternatively, depending on the latency and / or traffic capacity of the backhaul to which the base station or TRP is connected, the TRP may not be able to participate in cooperative transmission and / or cooperative reception in real time. The TRPs may be connected (e.g., associated) with the same base station or different base stations. The terminal can support JT by receiving a single DCI (sDCI) or multiple DCI (mDCI).

[0101] When sDCI is used, the terminal can transmit and receive data with the TRP. The TRPs can cooperate through the backhaul without delay. When mDCI is used, the terminal can transmit and receive data with some TRPs and other TRPs. However, if it is difficult for the TRPs to cooperate in real time through the backhaul, the terminal can perform communication using semi-static resources (e.g., divided semi-static resources).

[0102] To distinguish TRPs, a control resource set (CORESET) pool index may be introduced. The CORESET pool index may indicate a set of CORESETs. The transmission configuration indication (TCI) state of each CORESET may be independently indicated to the UE through signaling (e.g., RRC signaling and / or MAC CE signaling). The CORESET pool index may not necessarily correspond to the TRP. The TRP may be divided into transmission points (TxPs) and reception points (RxPs), and the CORESET pool index may correspond to the RxPs. For example, the Rx beam of a UE receiving a DL signal / channel from a TxP may be derived from the TCI state, and UL signals / channels scheduled by DCIs searched in a CORESET belonging to a CORESET pool corresponding to one CORESET pool index may be analyzed as being received at the same RxP. In the present disclosure, DL signals / channels may refer to DL signals and / or DL ​​channels, and UL signals / channels may refer to UL signals and / or UL channels.

[0103] When TRPs are synchronized and CSI reports are shared, performance gains can be achieved by coherent combining performed in the UE. If the above condition(s) are not met, non-coherent combining performed in the UE may be advantageous in terms of performance.

[0104] When a terminal is mounted on a vehicle, there are not many restrictions on the size and / or weight of the terminal. Portability can be taken into consideration for a terminal that is directly used by a person.

[0105] To extend the coverage area, small cells or IAB nodes can be deployed in a communication system. The transmission volume of small cells or IAB nodes can be affected by the quality of the backhaul. Ensuring backhaul (e.g., high-quality backhaul) can be expensive. As an alternative to this problem, a wireless relay device can be deployed in the communication system, and high-quality signals can be transmitted to terminals through the wireless relay device. Wireless relay devices can be categorized into various types depending on the method of transmitting signals. A wireless relay device supporting multiple functions can provide performance similar to that of a base station. When a wireless relay device supporting fewer functions is deployed, a communication system including the wireless relay device can be constructed at low cost. In the present disclosure, a wireless relay device can support a beamforming function and minimal function(s) for data transmission to terminal(s). A base station can transmit signals / channels to control the wireless relay device. The wireless relay device can receive signals / channels (e.g., control signals / control channels) from the base station and set appropriate parameters based on the received signals / channels. In other words, the base station can set appropriate parameters to the wireless relay device to control it.

[0106] A terminal can transmit UL signals / channels using multiple panels (e.g., multiple Tx panels). A terminal can perform simultaneous transmission across multiple UE panels (STxMP). Although the embodiments of the present disclosure will be described mainly with respect to a PUSCH transmission method, the embodiments may be equally or similarly applied to the transmission of other UL signals / channels (e.g., SRS, PUCCH). A Tx panel may be referred to as an antenna group or antenna port group. An antenna port group (e.g., an antenna group) may include two or more antenna ports. Coherence (e.g., phase continuity and / or power consistency) for antenna ports belonging to the same antenna port group may be maintained.

[0107] Scheduling information (e.g., DCI) of the PUSCH can indicate SRS resources to the UE. In other words, the DCI can include an SRS resource indicator (SRI). The UE can use one Tx panel or multiple Tx panels to transmit SRS on the SRS resources indicated by the SRI. In this disclosure, the Tx panel or panels can be interpreted as the Tx panel of the UE depending on the context. Multiple Tx panels can be used simultaneously to transmit SRS. When an SRS port or a DM-RS port is used as a radio resource, SRS transmission or DM-RS transmission can be performed regardless of the Tx panel. The UE can perform SRS transmission or DM-RS transmission based on STxMP. Alternatively, the UE can perform SRS transmission or DM-RS transmission using one Tx panel.

[0108] The UE can transmit UE capability information, including information indicating that the UE supports STxMP, to the base station. The base station can confirm that the UE supports STxMP through UE capability signaling. In this case, the base station can indicate two or more SRS resource sets to the UE through signaling (e.g., RRC signaling). The UE can confirm the SRS resource set indicated by the base station. Each SRS resource set can include one or more SRS resources. One SRS resource set can correspond to one Tx panel of the UE.

[0109] For example, in codebook-based PUSCH transmission, one SRS resource may correspond to a radio link from the Tx panel of the UE to the RxP. When a base station uses multiple RxPs, the base station may indicate an SRS resource set including multiple SRS resources to the UE through signaling (e.g., RRC signaling). The UE may derive the number of PUSCH DM-RS ports from the number of ports of the SRS resources indicated by the base station. The port of the SRS resource (e.g., the port of the SRS resource) may refer to the SRS port.

[0110] For example, in non-codebook-based PUSCH transmission, the SRS resource may correspond to a Tx beam of a wireless link from the Tx panel of the UE to the RxP. Each SRS resource may have one port.

[0111] The UE may receive signaling (e.g., RRC signaling) indicating one SRS resource set from the base station. The SRS resource set may be referred to as a qcl or TCI state of a Tx beam for transmitting a PUSCH. One TCI state or two or more TCI states for the PUSCH may be indicated to the UE. When the PUSCH is transmitted to two or more RxPs based on a time division multiplexing (TDM) scheme, the two or more TCI states (or one TCI state) may correspond to the Tx beam of the radio link for each RxP.

[0112] One TPMI (transmit precoding matrix indicator) or two or more TPMIs may be indicated to the UE. When the PUSCH is transmitted to two or more RxPs based on the TDM scheme, each of the two or more TPMIs (or one TPMI) may correspond to a Tx beam of a radio link for each RxP.

[0113] 1. PUSCH transmission method using STxMP in a single layer

[0114] Discrete Fourier Transform-Spread-Orthogonal Frequency Division Multiplexing (DFT-s-OFDM) or Cyclic Prefix (CP)-OFDM can be applied to PUSCH transmission. When PRBs are allocated consecutively and DFT precoding is additionally applied, the peak-to-average power ratio (PAPR) / cubic metric (CM) can be low due to the single carrier property. Considering the consecutively allocated PRBs and the implementation complexity of the DFT precoding engine, it is preferable that the number of PRBs is a multiple of 2, 3, or 5. DFT-s-OFDM can be primarily used in edge-of-coverage areas. In other words, DFT-s-OFDM can be used when one DM-RS port is used. Even in coverage border areas, CP-OFDM may be applied at the instruction of the base station, in which case there may be no restrictions on PRB allocation and / or the number of DM-RS ports.

[0115] If the number of DM-RS ports for PUSCH transmission is one, DFT-s-OFDM may be applied. In this case, if the UE has two or more DM-RS ports, it may be assumed that CP-OFDM is applied without additional signaling. Two or more DM-RS ports may be used in PUSCH transmission using STxMP. Therefore, even if one DM-RS port is used in each Tx panel, DFT-s-OFDM may not be applied.

[0116] Method 1-1: DFT-s-OFDM may not be applied to PUSCH transmission using STxMP.

[0117] In this disclosure, PUSCH transmission using STxMP may be referred to as "STxMP PUSCH transmission." Alternatively, DFT-s-OFDM may be applied to STxMP PUSCH transmission depending on UE capabilities. A terminal supporting STxMP may apply a DFT precoding engine to each Tx panel. For example, the terminal may reuse one DFT precoding engine in time to sequentially apply one DFT precoding engine to two or more Tx panels. For another example, the terminal may apply a DFT precoding engine to each Tx panel.

[0118] A terminal can apply one DFT precoding engine to one Tx panel according to UE capabilities (e.g., certain UE capabilities). In this case, if STxMP is configured in the terminal, the terminal cannot transmit a PUSCH to which DFT-s-OFDM is applied. Alternatively, according to UE capabilities (e.g., other UE capabilities), DFT precoding can be applied even when STxMP is configured in the terminal, so the terminal can transmit a PUSCH to which DFT-s-OFDM is applied.

[0119] Method 1-2: DFT-s-OFDM can be applied to STxMP PUSCH transmission depending on UE capability.

[0120] The UE can support STxMP using sDCI or mDCI. According to the method using sDCI, if the number of DM-RS ports is two or more, the UE can transmit a PUSCH to which CP-OFDM is applied. If the number of DM-RS ports is one (e.g., if the PUSCH is allocated using a fallback DCI format, if the use of DFT-s-OFDM is indicated in the UL BWP (bandwidth part), or if the application of DFT-s-OFDM is indicated using a scheduling DCI), the UE can transmit a PUSCH to which DFT-s-OFDM is applied.

[0121] Method 1-3: If the sDCI mode is supported (eg, if sDCI is used), the UE may not apply DFT-s-OFDM to STxMP PUSCH transmission.

[0122] The UE can transmit a PUSCH in sDCI mode, and two or more TRPs can receive the PUSCH. The UE can be indicated or configured for an SRS resource set and a second SRS resource set (or a first SRS resource set and a second SRS resource set). Scheduling information including a separate TPMI / RI, TPC parameter set, TPC command, SRI, and / or UL / transmission TCI can be indicated or configured for each SRS resource set.

[0123] In a first time resource, a PUSCH may be transmitted using scheduling information associated with a first SRS resource set. In a second time resource, a PUSCH may be transmitted using scheduling information associated with a second SRS resource set. The same method as above is applied to subsequent time resources, so that scheduling information associated with SRS resource sets may be alternately used for PUSCH transmission.

[0124] Alternatively, the PUSCH may be repeatedly transmitted using scheduling information associated with the first SRS resource set, and then the PUSCH may be repeatedly transmitted using scheduling information associated with the second SRS resource set.

[0125] When the backhaul connection between TRPs (or base stations) has a large latency, real-time cooperation between TRPs (or base stations) may be difficult. In this case, mDCI can be used. If DCI transmitted in one TRP assigns a PUSCH to a UE and DCI transmitted in another TRP also assigns a PUSCH to the UE, the UE can perform STxMP PUSCH transmission by applying a Tx beam (or TPMI) toward each TRP (or RxP). In this case, a DM-RS port for each DCI included in mDCI can be assigned to the UE, so the UE can transmit PUSCHs using two or more DM-RS ports.

[0126] A TRP may be scheduled for PUSCH transmission using both fallback and non-fallback DCI formats, while another TRP may be scheduled for PUSCH transmission using only the non-fallback DCI format. In this case, in STxMP PUSCH transmission, the UE may transmit a PUSCH using DFT-s-OFDM through one Tx panel, and the UE may transmit a PUSCH using CP-OFDM through another Tx panel.

[0127] Method 1-4: If the mDCI mode is supported (eg, if mDCI is used), the UE may apply DFT-s-OFDM to STxMP PUSCH transmission.

[0128] The TRP(s) that can use the fallback DCI format may be a serving TRP, and the TRP may be a TRP(s) connected to a base station using a Type 1 RACH procedure without additional signaling (e.g., RRC signaling). The TRP(s) that can use the fallback DCI format may be indicated to a terminal by signaling (e.g., RRC signaling). The TRP(s) that can use the fallback DCI format may be a TRP(s) that transmits a DCI format in a CORESET having a 'CORESET pool index = 0'. The search space and CORESET in which the fallback DCI format can be received may be limited to a CORESET having a specific CORESET pool index.

[0129] Method 1-5: The search space associated with the fallback DCI format may be associated with a specific CORESET (eg, a CORESET with a specific CORESET pool index).

[0130] 2. PHY processing method in STxMP mode

[0131] A transmission scheme that can be configured for a terminal in STxMP PUSCH transmission will be described. Although the embodiments of the present disclosure will be described mainly for a terminal having two Tx panels (e.g., Tx panel 0 and Tx panel 1), the embodiments may be equally or similarly applied to a terminal having two or more Tx panels.

[0132] The Tx panel of the terminal may be associated with an SRS resource set. The PUSCH transmission method may be instructed to the terminal through signaling (e.g., RRC signaling). The transmission method may be classified into an SFN transmission method and an SDM transmission method, and the base station may configure one of the SFN (single frequency network) transmission method and the SDM (spatial domain multiplexing) transmission method for the terminal.

[0133] The UE may transmit a PUSCH allocated according to a non-fallback DCI format (e.g., DCI format 0_1, DCI format 0_2, etc.). In this case, the UE may perform PUSCH transmission based on an SFN transmission scheme, an SDM transmission scheme, or another transmission scheme. PUSCH transmission scheduled according to the fallback DCI format may be performed based on a separate transmission scheme.

[0134] FIG. 3 is a conceptual diagram illustrating a first embodiment of SFN transmission.

[0135] Referring to FIG. 3, a base station can instruct a terminal to use an SFN transmission scheme (e.g., UL transmission based on the SFN transmission scheme). Multiple DM-RS ports can be instructed to the terminal. The terminal can transmit PUSCHs based on multiple DM-RS ports. In codebook-based transmission, Tx beam(s) for the DM-RS port(s) can be determined using one SRI belonging to the same SRS resource set, and a Transmit Rank Indicator (TRI) and TPMI can be applied to each Tx beam. In non-codebook-based transmission, each Tx beam can be determined using one or more SRIs (e.g., TRI SRIs) belonging to the same SRS resource set, and a separate TPMI may not be applied to each Tx beam.

[0136] Different coded bits can be mapped to each layer (or DM-RS port). Table 1 below shows the codeword-to-layer mapping for spatial multiplexing. In other words, Table 1 below shows how one codeword is mapped to one, two, three, or four layers for PUSCH transmission. d(.) may represent one coded bit that is the result of a low-density parity-check (LDPC) encoding operation. x(.) may represent the bit mapped to the layer. TPMI may be applied before the DM-RS port mapping operation. Alternatively, the same Tx beam as SRI may be applied.

[0137] [Table 1]

[0138] In codebook-based transmission, the available TPMIs may vary depending on the codebook subset (e.g., fullyAndPartialAndNonCoherent, partialAndNonCoherent, or noncoherent). The UE can select one of the available TPMIs (e.g., allowed TPMIs) based on a specific field included in the UL-DCI. The UL-DCI may be a DCI that schedules UL transmission. DM-RS ports 0 and 2 may be one coherence pair, and DM-RS ports 1 and 3 may be the other coherence pair. If a UE has two Tx panels and coherence is not maintained between the two Tx panels, it is preferable for the UE to assign the even-numbered DM-RS port(s) and the odd-numbered DM-RS port(s) to different Tx panels.

[0139] When a terminal is instructed to perform SFN transmission (e.g., an SFN transmission scheme), the terminal can transmit the same coded bits on each Tx panel. The same coded bits can be mapped to all DM-RS ports. Table 2 below shows codeword-to-layer mapping for SFN transmission. Referring to Table 2 below, coded bits can be mapped to layers, and layers can be mapped to DM-RS ports.

[0140] After codeword-to-layer mapping, a separate TPMI or SRI included in the SRS resource set can be applied to each Tx panel, or one TPMI can be applied to all Tx panels. In the example of Figure 3, DM-RS ports 0 and 2 can correspond to Tx panel 0, and DM-RS ports 1 and 3 can correspond to Tx panel 1.

[0141] [Table 2]

[0142] In the embodiment of Figure 3, the SRS resources selected from each SRS resource set (e.g., SRS resource set 0, SRS resource set 1) may have the same number of ports. In codebook-based transmission, the number of SRIs may be 1, and the number of DM-RS ports may be the same as the number of SRS ports. In non-codebook-based transmission, the number of SRS ports may be 1, and the number of SRIs may be the same as the number of DM-RS ports.

[0143] When one SRS resource has SRS ports 1000, 1001, ..., 1000+TRI-1, the same coded bits can be mapped to DM-RS ports corresponding to the same SRS port of the SRS resource. Each SRS port can be mapped to a different DM-RS port. This mapping relationship can be applied to codebook-based transmission.

[0144] When two or more SRS resources are selected by an SRI, the order of the SRI(s) in each SRS resource set can correspond to the relative order of the DM-RS ports. The number of SRI(s) selected from each SRS resource set can be the same. The number of SRS resources included in each SRS resource set can always be the same, or the number of SRS resources included in each SRS resource set can be different.

[0145] SRIs with a relative order may be associated with the same coded bit. This association may be applied to non-codebook based transmission.

[0146] Table 3 below may show an SRI indication for non-codebook-based PUSCH transmission. In other words, Table 3 below may show a method for analyzing the SRI field included in UL-DCI. Table 4 below may show a second SRI indication for non-codebook-based PUSCH transmission. In other words, Table 4 below may show a method for analyzing the second SRI field included in UL-DCI. The UE may consider a case where the SRS resource set includes four SRS resources. In other words, NSRS may be 4. NSRS may indicate the number of SRS resources. Two or less DM-RS ports may be indicated to the UE. In other words, L max can be 2. L max The SRI field may indicate the maximum number of DM-RS ports (e.g., layers) that can be configured in a terminal. The SRI field and the second SRI field may each indicate an SRS resource(s) selected from an SRS resource set. The SRI field and the second SRI field may indicate the same number of indexes. For example, if the SRI field indicates indexes 0 to 3 (e.g., 4 indexes), the second SRI field may indicate indexes 0 to 3 (e.g., 4 indexes). If the SRI field indicates indexes 4 to 9 (e.g., 6 indexes), the second SRI field may indicate indexes 0 to 5 (e.g., 6 indexes). SRIs with the same relative order (e.g., SRIs in the first SRS resource set and SRIs in the second SRS resource set) may correspond to different DM-RS ports, and different DM-RS ports may correspond to the same coded bits.

[0147] [Table 3]

[0148] [Table 4]

[0149] Method 2-1: When a terminal is instructed to perform SFN transmission (e.g., SFN transmission mode) and the port(s) corresponding to the SRS resource(s) selected from the first SRS resource set are the same as the port(s) corresponding to the SRS resource(s) selected from the second SRS resource set, the same coded bits may be mapped to the port(s) associated with each SRS resource set. The ports of the SRS resources may be mapped to different DM-RS ports.

[0150] FIG. 4 is a conceptual diagram illustrating a second embodiment of SFN transmission.

[0151] Referring to FIG. 4, multiple DM-RS ports may be indicated to a terminal, and the terminal may transmit a PUSCH based on the multiple DM-RS ports.

[0152] If one SRS resource has SRS ports 1000, 1001, ..., 1000+TRI-1, the same coded bits may be mapped to DM-RS ports corresponding to the same SRS port of the SRS resource. The Tx panels of a terminal may be mapped to the same DM-RS port. The terminal may transmit a PUSCH using Tx panels that share the same DM-RS port. The base station may receive a PUSCH DM-RS from the terminal, estimate an effective channel response based on the PUSCH DM-RS, and decode data (e.g., a PUSCH) based on the estimated channel response. In this disclosure, the PUSCH DM-RS may be a DM-RS for demodulating and / or decoding a PUSCH.

[0153] When two or more SRS resources are selected by an SRS, the order of the SRI(s) in each SRS resource set can correspond to the relative order of the DM-RS ports. The number of SRI(s) selected from each SRS resource set can be the same. Each SRS resource set can contain the same number of SRS resources, or each SRS resource set can contain a different number of SRS resources.

[0154] SRIs with a relative order may be associated with the same coded bit, and this association can be utilized in non-codebook-based transmission.

[0155] The SRI field in Table 3 and the second SRI field in Table 4 may indicate the same number of indexes. The relative order of the indexes indicated by the SRI field and the second SRI field may be maintained, and the SRI field and the second SRI field may each correspond to the same DM-RS port.

[0156] Method 2-2: When SFN transmission (e.g., SFN transmission mode) is instructed to a terminal and the SRS resource(s) selected from each SRS resource set correspond to the same DM-RS port, the same coded bits may be mapped to the port (e.g., DM-RS port). The ports of each SRS resource may be mapped to the same DM-RS port.

[0157] In this method, one DM-RS port can be mapped to one or more SRS resource(s), where the SRS port can be used to represent a Tx beam of the PUSCH (or PUCCH), and the DM-RS port can be used for data mapping and channel estimation of the PUSCH (or PUCCH).

[0158] The terminal may perform an operation of mapping coded bits to layers as many times as the number of Tx panels. The operation of mapping coded bits to layers may be performed independently. For example, if the terminal has two Tx panels, the mapping operation according to Table 1 may be repeated twice. If the number of ports used by the terminal for transmission is limited to four, coded bits may be mapped to up to two layers according to Table 1. To explain the operation, the following Table 5 may be considered. Table 5 may show codeword-to-layer mapping for SFN transmission. The transmit output of Tx panel 0 may be referred to as x, and the transmit output of Tx panel 1 may be referred to as y. d may be referred to as the transmit input of Tx panel 0 and Tx panel 1.

[0159] One TPMI can apply to all Tx panels, or a separate TPMI or SRI included in the SRS resource set can apply to each Tx panel. In this case, DM-RS ports 0, 1, 2, and 3 in the example of FIG. 4 can correspond to each Tx panel.

[0160] [Table 5]

[0161] FIG. 5 is a conceptual diagram illustrating a first embodiment of SDM transmission.

[0162] Referring to FIG. 5, different coded bits may be mapped to each Tx panel. In codebook-based PUSCH transmission, one Tx panel may correspond to one SRS resource set. Therefore, a common TPMI may be applied to DM-RS ports (e.g., DM-RS ports 0 and 2, or DM-RS ports 1 and 3) corresponding to SRS resource(s) belonging to the same SRS resource set. A TPMI (e.g., a common TPMI) may also be applied when the number of Tx panels in the PUSCH transmission is analyzed as one rather than multiple. In STxMP PUSCH transmission, two TPMIs may be indicated to the UE, and one TPMI may be indicated to the UE when the UE uses one Tx panel. This operation may be applied when the sDCI mode is used in the mTRP scenario.

[0163] FIG. 6 is a conceptual diagram illustrating a second embodiment of SDM transmission.

[0164] Referring to FIG. 6, different codewords can be mapped for each Tx panel (or DM-RS port(s) corresponding to an SRS resource set). If four or fewer layers are used for transmission, one codeword can be mapped. In the proposed method, even if four or fewer layers are used for transmission, two codewords can be mapped depending on the number of Tx panels.

[0165] Method 2-3: When SDM transmission (eg, SDM transmission method) is instructed to a terminal, different coded bits may be mapped to each SRS resource set.

[0166] Up to four layers (or DM-RS ports) may be supported in STxMP PUSCH transmission, and the number of layers (L) for transmission in each Tx panel may not be greater than 4. In other words, if L1 layers are used for transmission in the first SRS resource set, L2 (= L - L1) or less layers may be used for transmission in the second SRS resource set.

[0167] For example, L1 may be 0, 1, 2, or 3, and L2 may be equal to or less than L-L1, where L2 may be 0, 1, 2, or 3. In this case, a separate TPMI may be indicated for each Tx panel. Alternatively, one TPMI may be indicated to the terminal, and the terminal may apply one TPMI to all Tx panels.

[0168] Method 2-4: A combination of L1 and L2 that satisfies the L1+L2 condition in Method 2-3 is acceptable.

[0169] As another example, L1 may be 0, 1, or 2. L2 may be equal to or less than L-L1, and L2 may be 0, 1, or 2. In this case, a separate TPMI may be indicated for each Tx panel, and the terminal may apply a separate TPMI to each Tx panel.

[0170] Method 2-5: In Method 2-3, a combination of L1 and L2 that satisfies the condition of L1+L2 and all the conditions of L1 and L2 is acceptable.

[0171] When the mDCI mode is indicated in the mTRP scenario, the UE may transmit a PUSCH scheduled by one TRP and a PUSCH scheduled by another TRP using different Tx panels. In this case, different layers may be mapped to PUSCH transmission, as in the embodiment of FIG. 6.

[0172] The base station can instruct the terminal to transmit either STxMP PUSCH transmission or non-STxMP PUSCH transmission (e.g., TDM PUSCH transmission) through signaling (e.g., RRC signaling). The terminal can confirm the transmission (e.g., STxMP PUSCH transmission or non-STxMP PUSCH transmission) instructed by the base station signaling (e.g., RRC signaling). Non-STxMP PUSCH transmission may refer to non-STxMP-based PUSCH transmission. TDM PUSCH transmission may refer to TDM-based PUSCH transmission.

[0173] STxMP PUSCH transmission may be performed based on SFN transmission mode or SDM transmission mode. The base station may indicate the transmission mode for STxMP PUSCH transmission to the terminal through signaling. The terminal may confirm the transmission mode (e.g., SFN transmission mode or SDM transmission mode) indicated by base station signaling (e.g., RRC signaling). Alternatively, when sDCI mode or mDCI mode is selected, SFN transmission mode or SDM transmission mode may be implicitly selected.

[0174] When the SFN transmission mode is used, a scheme of sharing a DM-RS port or a scheme of not sharing a DM-RS port can be considered.

[0175] A UE can dynamically switch between STxMP (e.g., STxMP PUSCH transmission) and non-STxMP (e.g., non-STxMP PUSCH transmission). Non-STxMP can be analyzed as an operation supported by technical standards. STxMP can be classified as STxMP SDM or STxMP SFN. STxMP SDM can be STxMP based on the SDM transmission method. STxMP SFN can be STxMP based on the SFN transmission method.

[0176] When a terminal operates in STxMP SDM, the maximum number of schedulable layers (maxLayer) or the maximum number of schedulable ranks (maxRank) may have different values ​​for each Tx panel. The base station can notify the terminal of the (maxLayer, maxRank) pair for each Tx panel through signaling (e.g., RRC signaling). The terminal can check the (maxLayer, maxRank) pair for each Tx panel indicated by base station signaling (e.g., RRC signaling). The (maxLayer, maxRank) combination(s) for each Tx panel may be limited by technical standards. Alternatively, the (maxLayer, maxRank) combination(s) for each Tx panel may be limited by the scheduler.

[0177] If a terminal can perform transmission for up to four layers, the base station can instruct maxLayer=4 to the terminal. Some combinations may be restricted for maxLayer1 and maxLayer2 separately instructed to the terminal. This is because maxLayer1=4 associated with Tx panel 1 and maxLayer2=4 associated with Tx panel 2 may be instructed to the terminal. According to technical standards, the relationship maxLayer1+maxLayer2≦maxLayer may be maintained. Alternatively, according to technical standards, the relationship maxLayer1≦maxLayer and the relationship maxLayer2≦maxLayer may be maintained. In this case, the scheduler can perform scheduling to satisfy the relationship maxLayer1+maxLayer2≦maxLayer.

[0178] When a UE operates in STxMP SFN, the maxLayer or maxRank value for non-STxMP may be reused as the maxLayer or maxRank value for STxMP SFN. Alternatively, the maxLayer or maxRank for STxMP SFN may have a separate value from the maxLayer or maxRank for non-STxMP. To support this operation, the base station may indicate the maxLayer or maxRank value for STxMP SFN to the UE through signaling (e.g., RRC signaling). The UE may confirm the maxLayer or maxRank value for STxMP SFN through signaling from the base station. The maxLayer value supported in STxMP SFN may not be greater than the maxLayer value supported in non-STxMP.

[0179] 3. How to apply transform precoding in STxMP PUSCH transmission

[0180] The UE can transmit PUSCH scheduled according to the fallback DCI format. The UE can map one codeword to one DM-RS port. When the UE is in an RRC connected state in FR2, it can be assumed that PUSCH is not scheduled according to the fallback DCI format in an UL BWP with PUCCH resources for which the spatial relation of the PUCCH or UL / joint TCI is not configured. Exceptionally, if enableDefaultBeamPL-ForPUSCH0-0 is enabled, PUSCH can be scheduled.

[0181] The base station may indicate dedicated PUCCH resources to the terminal through signaling (e.g., RRC signaling). The same spatial relationship as that of the dedicated PUCCH resource with the lowest ID among the dedicated PUCCH resources indicated to the terminal through signaling (e.g., RRC signaling) may be applied to PUSCH transmission. This operation may be applied at least to a serving cell in which the PUCCH may be transmitted. If carrier aggregation (CA) is configured for the terminal, the same spatial relationship (e.g., the same Tx beam) as that of the dedicated PUCCH resource with the lowest ID in other serving cells may be applied to PUSCH transmission.

[0182] If the use of a default beam is allowed (e.g., enableDefaultBeamPL-ForPUSCH0-0 is enabled), UL BWP 1, where PUCCH is not configured, and UL BWP 2, where PUCCH is configured, may be considered. In UL BWP 2, PUCCH may be configured, but spatial relationships may not be configured for all PUCCH resources. The default beam may be used for path loss estimation and / or Tx beam derivation to determine transmit power.

[0183] To transmit a PUSCH in UL BWP 1, the terminal can derive a Tx beam using a default beam. To transmit a PUSCH in UL BWP 2, the terminal can derive a Tx beam using a default beam.

[0184] The default beam can be derived using a reference signal (RS) that considers qcl type D, which is the TCI state of the CORESET with the lowest ID among the CORESETs configured in the DL BWP of the serving cell (e.g., a serving cell including UL BWP 1 or UL BWP 2). If the CORESET has two TCI states, the UE can use the first TCI state of the two TCI states to derive the default beam.

[0185] The base station may transmit information indicating whether transform precoding is applied to the PUSCH allocated by the fallback DCI to the terminal through signaling (e.g., RRC signaling). The terminal may check whether transform precoding is applied to the PUSCH based on the base station signaling (e.g., RRC signaling). In this case, a value associated with an active UL BWP may not be applied. The waveform for the PUSCH allocated by the non-fallback DCI may be determined by applying a value associated with an active UL BWP. When a value associated with an active UL BWP is indicated to the terminal, the waveform may be changed according to the scheduling information of the PUSCH. Alternatively, the PUSCH waveform may be changed by the MAC CE.

[0186] For example, waveform 0 may be associated with an active UL BWP, but waveform 1 may be indicated to the terminal by specific scheduling information or MAC CE.

[0187] DFT-s-OFDM can be allocated in a single layer when transform precoding is enabled and the number of scheduled PRBs is allocated successively in multiples of 2, 3, or 5. Fallback DCI can always schedule a single layer.

[0188] When signaling (e.g., RRC signaling) instructs a terminal to perform STxMP or PUSCH repeated transmission, two or more SRS resource sets may be indicated to the terminal. Therefore, detailed operations need to be instructed to the terminal. According to the proposed method, the base station can explicitly instruct the terminal of an SRS resource set through signaling (e.g., RRC signaling). Alternatively, the terminal can determine the SRS resource set based on other information. Once the SRS resource set is determined, the SRS port for the SRS resources available to the terminal can be indicated as a DM-RS port.

[0189] Method 3-1: When transmission for one layer is performed per Tx panel (or SRS resource set), a transform precoder can be applied.

[0190] Method 3-2: In Method 3-1, to transmit PUSCHs corresponding to all Tx panels (or all SRS resource sets), transform precoding may or may not be applied.

[0191] The UE can change the PUSCH waveform according to the scheduling information. In other words, the UE can enable or disable transform precoding in the scheduling information. When the UE operates in sDCI mode, the UE can operate according to one scheduling information. Therefore, the UE can use the same waveform in all Tx panels.

[0192] When the UE operates in mDCI mode, the UE may receive different scheduling information for each Tx panel (or SRS resource set). If the wireless channel conditions differ for each Tx panel, the UE may determine whether to apply transform precoding for each Tx panel. Even when the UE operates in sDCI mode, the UE may determine whether to apply transform precoding for each Tx panel in a specific scenario.

[0193] For example, transmission for one layer may be performed in one Tx panel, and transmission for two layers may be performed in another Tx panel. In this case, the UE may perform transform precoding in the Tx panel where transmission for one layer is performed.

[0194] For example, the timing advance (TA) for one Tx panel may be different from the TA for another Tx panel, and the difference between the path loss for one Tx panel and the path loss for another Tx panel may be large. In this case, even when transmission for one layer is performed in each Tx panel, it may be preferable to perform transform precoding in any one Tx panel.

[0195] Method 3-3: In Method 3-1, transform precoding may be applied for the transmission of a PUSCH corresponding to one Tx panel (or SRS resource set), but transform precoding may not be applied for the transmission of a PUSCH corresponding to another Tx panel (or SRS resource set).

[0196] In various embodiments of STxMP, the application of transform precoding can be considered.

[0197] The UE may operate in STxMP SFN mode 1 as shown in FIG. 3. The UE may perform transmission for different DM-RS ports through a Tx panel. The UE may transmit a PUSCH using two DM-RS ports (or two layers). Since each Tx panel may have one DM-RS port, transform precoding may be applied to all or part of the Tx panel.

[0198] The terminal can operate in STxMP SFN mode 2 as shown in Figure 4. DM-RS ports can be shared in the Tx panel. Therefore, one DM-RS port can be applied, and transform precoding can be analyzed as being applied to all Tx panels.

[0199] The terminal can operate in STxMP SDM mode 1 shown in Figure 5. STxMP SDM mode 1 can be applied in sDCI mode or mDCI mode. When one DM-RS port is applied in the Tx panel, transform precoding can be applied in the Tx panel.

[0200] The terminal can operate in STxMP SDM mode 2 shown in Figure 6. STxMP SDM mode 2 can be applied in sDCI mode or mDCI mode. When one DM-RS port is applied in the Tx panel, transform precoding can be applied in the Tx panel.

[0201] When the UE performs repeated PUSCH transmission, a different number of layers may be scheduled for each Tx panel or SRS resource set. Transform precoding may be applied to a Tx panel to which one layer is assigned. Even if only one layer is assigned to a Tx panel according to the scheduling information, the UE may or may not apply transform precoding.

[0202] 4. STxMP PUSCH transmission method considering DWS (dynamic waveform switching)

[0203] DFT precoding for a dynamically allocated PUSCH can be dynamically applied or not applied. A PUSCH that a UE can transmit with an active UL BWP can have multiple waveforms. The PUSCH waveform can be classified into the same waveform as the Msg3 PUSCH and a waveform associated with the UL BWP. The waveform can refer to DFT-s-OFDM to which DFT precoding is applied or CP-OFDM to which DFT precoding is not applied.

[0204] If the UL-DCI received by the UE is in DCI format 0_0, or if the UL-DCI is received in a cell-specific search space or common search space (CSS), the waveform of the PUSCH scheduled by the UL-DCI may be the same as the waveform of the Msg3 PUSCH. If the UL-DCI received by the UE is in DCI format 0_1, or if the UL-DCI received by the UE is in DCI format 0_2, or if the UL-DCI is received in a UE-specific search space (USS), the waveform of the PUSCH scheduled by the UL-DCI may be the same as the waveform derived by the UL BWP configuration.

[0205] When a terminal is located at the edge of a base station's coverage, the link budget for DFT-s-OFDM-based PUSCH transmission may be greater than the link budget for CP-OFDM-based PUSCH transmission. A terminal located at the center of a base station's coverage may move to the edge of the base station's coverage due to mobility. Even when the terminal moves from the center to the edge of coverage, it is preferable that the terminal be able to dynamically change the PUSCH waveform to ensure stable communication of the terminal without performing a separate procedure.

[0206] To dynamically change the waveform, the UE can receive scheduling information to change the UL BWP. In the procedure for changing (or re-instructing) the UL BWP, the DFT precoder can be applied or not applied, and the RF (radio frequency) returning operation can be performed again. Therefore, unnecessary operations need to be omitted.

[0207] The UL DCI may include an information field (e.g., a DWS field or a TPI (Transform Precoding Inductor) field) that dynamically indicates a waveform. When the DWS field has a first value, the terminal can apply a DFT precoder. When the DWS field has a second value, the terminal may not apply a DFT precoder.

[0208] The amount and / or type of information scheduled for each waveform may vary. To support this operation, known bits may be added to the information field(s) included in the UL DCI so that the information field(s) have a length independent of the waveform. Each information field may have a longer length depending on the waveform. When a waveform with a shorter length is applied, the scheduling information may be parsed based on a portion of the information field (e.g., LSBs (least significant bits) or MSBs (most significant bits)).

[0209] Considering repeated transmission of PUSCH, the Tx panel, SRS resource set, or waveform applied by the UE for each PUSCH transmission may be different. This is because the TRP at which the PUSCH is expected to be received may be different for each PUSCH transmission. Since the link budget between the UE and the TRP may be different, it is preferable that the DWS information be indicated for each link (e.g., for each TRP).

[0210] Considering STxMP PUSCH transmission, the waveform applied to each Tx panel of the UE may be different. Alternatively, the waveform applied to each TRP (or Rx panel of the TRP) to which the UE is transmitting may be different. Therefore, it is preferable that the DWS field be indicated for each link. The following method can be applied to other scenarios including not only a UL-DCI for scheduling STxMP PUSCH transmission but also two UL-TCIs, two TPMIs, or two SRS resources (e.g., SRS resource identifiers).

[0211] According to the proposed method, the size of the DWS field included in the UL-DCI can be 1 bit, and the DWS field can be commonly applied to all links. In this case, the waveforms can be different for each Tx panel.

[0212] Method 4-1: The size of the DWS field included in the UL-DCI may be 1 bit, and the terminal may derive a waveform by commonly applying the DWS field to all PUSCHs.

[0213] When a UE performs STxMP SDM PUSCH transmission, the UE can perform transmission for one layer in one Tx panel. The UE can determine the waveform for the Tx panel based on the value of the DWS field. If transmission for two or more layers is performed in another Tx panel, the DWS field may not be applied to the other Tx panel.

[0214] When the UE performs STxMP SDM PUSCH transmission or STxMP SFN PUSCH transmission, the UE can perform transmission for one layer in all Tx panels. The UE can determine the waveform for the Tx panel based on the value of the DWS field. The waveform may be the same in all Tx panels.

[0215] If DFT precoding is performed according to the value of the DWS field, the terminal may assume that one layer is assigned.

[0216] When the UE performs STxMP SDM PUSCH transmission or STxMP SFN PUSCH transmission, two or more SRS resource sets (e.g., a first SRS resource set and a second SRS resource set) may be indicated or configured to the UE. The DWS field of the UL-DCI may be indicated or configured with one bit, and the DWS field may be interpreted as indicating DFT precoding for any one of the SRS resource sets.

[0217] "A certain SRS resource set selected from two or more SRS resource sets" or "a selection method for a certain SRS resource set among two or more SRS resource sets" may be defined in a technical specification. Alternatively, "a certain SRS resource set selected from two or more SRS resource sets" or "a selection method for a certain SRS resource set among two or more SRS resource sets" may be indicated to a terminal by higher layer signaling. The following method is applicable to the case of two SRS resource sets, but can be easily extended to the case of three or more SRS resource sets.

[0218] Method 4-2: The DWS field may be analyzed based on the presence or absence of DFT precoding for the first SRS resource set, and may not be used as information for the second SRS resource set.

[0219] Method 4-3: The DWS field may be analyzed based on the presence or absence of DFT precoding for the second SRS resource set, and may not be used as information for the first SRS resource set.

[0220] Method 4-4: The SRS resource set to which the DWS field applies can be indicated or set from higher layer signaling, and the first SRS resource set or the second SRS resource set can be selected, and the DWS field can be applied only to the selected SRS resource set.

[0221] According to the proposed method, the size of the DWS field included in the UL-DCI may be 2 bits, and different waveforms may be used in each Tx panel.

[0222] Method 4-5: The size of the DWS field included in the UL-DCI may be 2 bits, and the terminal may derive a waveform for each PUSCH by applying the DWS field to each of all PUSCHs.

[0223] Method 4-6: The size of the DWS field included in the UL-DCI may be 2 bits, and the 2 bits may be consecutive or non-consecutive. Another information field may be placed between the 2 non-consecutive bits.

[0224] The DWS field included in the UL-DCI can be analyzed as a bitmap. The MSB of the DWS field can correspond to one Tx panel. The LSB of the DWS field can correspond to another Tx panel.

[0225] The DWS field included in the UL-DCI can be parsed as a bitmap. The MSB of the DWS field can correspond to one TRP (or the Rx panel of the TRP, the CORESET pool index associated with the search space set / CORESET in which the UL-DCI was detected), and the LSB of the DWS field can correspond to another TRP (or the Rx panel of the TRP, the CORESET pool index associated with the search space set / CORESET in which the UL-DCI was detected).

[0226] In an sDCI-based mTRP scenario, the UE can repeatedly transmit the PUSCH. Assuming that the PUSCH is received by each TRP, the TPMI, SRS resource (e.g., SRI), and / or UL-TCI corresponding to the link with the TRP may be separately indicated to the UE. One TB may be allocated, and the UE may transmit one TB on the PUSCH. In this case, one TB may be received by two TRPs. Therefore, even when two TPMI / UL-TCI / SRI are indicated to the UE, transmission for the same number of layers may be performed. In this case, Method 4-1, Method 4-5, and / or Method 4-6 may also be applied.

[0227] It may be indicated that transmission for one layer is performed for each TRP in a TDM manner. In this case, the UE may or may not commonly apply DFT precoding to the link. To support this operation, one value of the DWS field may correspond to all TRPs, and the UE may or may not apply DFT precoding to all PUSCH transmissions.

[0228] It may be indicated that transmission for one layer is performed for each TRP in a TDM manner. In this case, the UE may or may not apply DFT precoding to each link. To support this operation, the size of the DWS field may be n bits, where n may be an integer greater than or equal to 2. The MSB of the n bits may correspond to one TRP (or the Rx panel or CORESET pool index of the TRP). The LSB of the n bits may correspond to another TRP (or the Rx panel or CORESET pool index of the TRP).

[0229] 5. STxMP PUCCH Transmission Method

[0230] The UE may use a PUCCH (or a PUSCH) to transmit UCI. If a PUCCH symbol overlaps with a PUSCH symbol, UCI may be transmitted using the PUSCH instead of the PUCCH. A PUCCH symbol may refer to a symbol on which PUCCH transmission is performed. A PUSCH symbol may refer to a symbol on which PUSCH transmission is performed. If the priority index of the PUCCH can be compared with the priority index of the PUSCH, inter-band CA may be activated, and PUCCH transmission and PUSCH transmission may be performed simultaneously in different frequency bands. If the above conditions are not met, the UE may drop PUCCH transmission and perform PUSCH transmission.

[0231] A terminal can transmit the PUCCH using one DM-RS port. The Tx beam referenced by the PUCCH DM-RS port can be the default beam, or the Tx beam referenced by the PUCCH DM-RS port can be explicitly indicated by the TCI status or spatial relationship information.

[0232] If a terminal has two or more Tx panels, the terminal can transmit PUCCH using one DM-RS port. In this case, operation according to the technical standard can be performed. The base station can instruct the terminal to support two or more DM-RS ports. In this case, the terminal can perform transmission using two or more DM-RS ports on two or more Tx panels instead of one Tx panel.

[0233] DM-RS ports can have orthogonal radio resources. The same DM-RS port can be used, and the radio channel estimated by the base station can represent two or more links. In this case, the operation of the terminal can be inaccurate.

[0234] Method 5-1: Two or more PUCCH DM-RS ports can be indicated to the terminal.

[0235] A UE can support as many DM-RS ports as there are Tx panels (or as many antenna groups (Ng)). When two or more DM-RS ports are used, a cyclic shift, an orthogonal cover code (OCC), and / or a base sequence may be additionally assigned. The resources of the DM-RS ports may be determined taking into account the PUCCH format.

[0236] Method 5-2: An additional offset for the cyclic shift of an additional PUCCH DM-RS port may be indicated to the terminal by signaling (eg, RRC signaling).

[0237] When PUCCH format 0 is used, according to method 5-2, one cyclic shift may be indicated by information indicated by terminal scheduling information and / or signaling (e.g., RRC signaling), and the one cyclic shift may be used to derive a sequence for PUCCH DM-RS port 0, and "one cyclic shift + additional offset" may be used to derive a sequence for PUCCH DM-RS port 1. In this case, the base station knows that the multiplexing capacity of PUCCH format 0 is reduced and can reflect the multiplexing capacity in scheduling for multiple users.

[0238] The value of the additional offset can be +1 or -1. If a terminal transmits a 2-bit HARQ-ACK, the terminal can use 4 cyclic shifts. To maximize detection performance at the base station, the difference between adjacent cyclic shifts can be 3. If a terminal transmits a 1-bit HARQ-ACK, the value of the adjacent cyclic shift can be 6. Therefore, it is preferable that the additional offset for the cyclic shift is not set to 3 or 6. It is preferable that the terminal use adjacent cyclic shifts. Adjacent cyclic shifts can be expressed as ±1.

[0239] Method 5-3: An additional offset for the OCC of the additional PUCCH DM-RS port may be indicated to the terminal by signaling (eg, RRC signaling).

[0240] When PUCCH format 1 or PUCCH format 4 is used, according to method 5-3, one index may be indicated by information indicated by the terminal's scheduling information and / or signaling (e.g., RRC signaling), one index may be used to derive the OCC to be applied to PUCCH DM-RS port 0, and "one index + additional offset" may be used to derive the OCC to be applied to PUCCH DM-RS port 1.

[0241] To satisfy frequency domain restrictions in communication systems supporting unlicensed bands, PRBs may be allocated so that PUCCH resources have an interlaced mapping. PRBs may be spread so that PUCCH resources have an interlaced mapping. In this case, since the multiplexing capacity is reduced, an additional spreading sequence may be applied in scheduling for multiple users. According to method 5-3, an additional OCC may be used, and the additional OCC may be applied to PUCCH DM-RS port 1. The additional OCC may be an OCC to which an additional offset is applied.

[0242] When the amount of UCI is large, in PUCCH format 2 and / or PUCCH format 3, the terminal may compare a code rate (hereinafter referred to as a "reference code rate") indicated by signaling (e.g., RRC signaling) with the effective code rate of the UCI. The terminal may determine whether the effective code rate is higher or lower than the reference code rate. If the effective code rate is higher than the reference code rate, the terminal may not select a PUCCH associated with the effective code rate and may select another PUCCH that includes more PRBs than the PUCCH. For example, considering a PUCCH that transmits a CSI report, two PUCCH resources may be indicated to the terminal, and the terminal may select one of the two PUCCH resources.

[0243] If the effective code rate is lower than the reference code rate, the UE may perform an operation to reduce the number of PRBs. Alternatively, the UE may reduce the amount of UCI. For example, the UE may drop a CSI report with a low priority. The CSI report may be divided into CSI part 1 and CSI part 2. In this case, the UE may drop CSI part 2 and transmit CSI part 1. Alternatively, the UE may transmit CSI part 1. In other words, the UE may select CSI report(s) with a high priority and transmit the selected CSI report(s). Alternatively, the UE may transmit all of CSI part 1 and part of CSI part 2. In this case, the part of CSI part 2 transmitted by the UE may be CSI part 2 belonging to the CSI report with a high priority.

[0244] JPEG2025539005000007.jpg74170

[0245] If two or more DM-RS ports are supported, the UE can utilize all Tx panels based on STxMP for PUCCH transmission. In this case, the base station can instruct the UE to perform one of STxMP SFN PUCCH transmission or STxMP SDM PUCCH transmission. Alternatively, the performance of STxMP SFN PUCCH transmission or STxMP SDM PUCCH transmission can be determined based on technical specifications. Alternatively, the technical specifications can specify only one of STxMP SFN PUCCH transmission or STxMP SDM PUCCH transmission. STxMP SFN PUCCH transmission may mean STxMP PUCCH transmission based on SFN mode. STxMP SDM PUCCH transmission may mean STxMP PUCCH transmission based on SDM mode.

[0246] Coded UCI in STxMP SFN PUCCH transmission may be commonly mapped to all DM-RS ports. Coded UCI in STxMP SDM PUCCH transmission may be mapped based on codeword-to-layer mapping. STxMP may be a procedure related to the transmission of coded UCI, and transmission related to DM-RS ports may be performed differently from STxMP. For example, coded UCI may be transmitted based on STxMP SFN PUCCH transmission, but two or more DM-RS ports may be indicated, and the two or more DM-RS ports may use orthogonal resources.

[0247] When STxMP SDM PUCCH transmission is performed, different methods may be applied depending on the PUCCH format.

[0248] Method 5-4: When PUCCH format 0 and / or PUCCH format 1 are used, the same sequence may be mapped and transmitted to all layers. It is preferable that the mathematical formula applied to PUCCH format 2, PUCCH format 3, and / or PUCCH format 4, in which 3 or more bits of UCI may be transmitted, be changed.

[0249] JPEG2025539005000008.jpg26170

[0250] If L≦2, the effective code rate of the UCI may be reduced to 1 / L. The terminal may generate coded UCI by performing an encoding procedure on the UCI and may perform a modulation procedure on the coded UCI. Then, the terminal may perform a codeword-to-layer mapping procedure.

[0251] Method 5-6: Depending on the amount of UCI type (e.g., HARQ-ACK, CSI, etc.), one codeword or two codewords for UCI may be generated. The codeword-to-layer mapping procedure for the codeword(s) may be performed according to the order considered in the technical standard. For example, the codeword-to-layer mapping procedure for HARQ-ACK may be performed first, and then the codeword-to-layer mapping procedure for CSI may be performed.

[0252] UCIs having different UCI types can belong to different codewords (or different coding procedures). If the number of UCIs is large, a segmentation procedure can be performed on the corresponding UCI. If a UCI type (e.g., a UCI having a UCI type) is divided into two codewords, the terminal can perform a layer-to-port mapping procedure on the first codeword and a codeword-to-layer mapping procedure on the second codeword.

[0253] According to Methods 5-6, the codeword mapping method for UCI types (e.g., codeword to layer mapping method) can be expressed as shown in Table 6 below. Table 6 can show the codeword to layer mapping method when SDM mode is used. x (n) (i) may refer to the i-th coded bit (e.g., modulation symbol, d(i)) mapped to DM-RS port n. The terminal may apply the same procedure to other UCI types according to the order of consideration in the technical standard.

[0254] [Table 6]

[0255] When STxMP SFN PUCCH transmission is performed, the terminal may apply the same method (e.g., the same procedure) regardless of the PUCCH format. For example, for PUCCH format 0 and / or PUCCH format 1, the same sequence may be mapped to all layers.

[0256] Methods 5-7: For PUCCH format 0 and / or PUCCH format 1, the same sequence may be mapped to and transmitted in all layers. Preferably, the mathematical formulas that apply to PUCCH format 2, PUCCH format 3, and / or PUCCH format 4, in which 3 or more bits of UCI may be transmitted, are reused.

[0257] According to Methods 5-7, the codeword mapping method for UCI types (e.g., codeword to layer mapping method) can be expressed as shown in Table 7 below. Table 7 shows the codeword to layer mapping method when SFN mode is used. x (n) (i) may refer to the i-th coded bit (e.g., modulation symbol, d(i)) mapped to DM-RS port n. The terminal may apply the same procedure to other UCI types according to the order of consideration in the technical standard.

[0258] [Table 7]

[0259] When a terminal supports two or more PUCCH DM-RS ports, one DM-RS port (e.g., each PUCCH DM-RS port) can correspond to each Tx panel. In this case, a transform precoder can be applied for each Tx panel. A transform precoder can be applied in PUCCH format 3 or PUCCH format 4.

[0260] Method 5-8: When a terminal uses two or more DM-RS ports, the terminal can also apply a transformation precoder to each DM-RS port.

[0261] Bits coded in STxMP SDM PUCCH transmission can be distributed across layers. Therefore, the UE can apply a transformation precoder to each DM-RS port (or Tx panel). Bits coded in STxMP SFN PUCCH transmission can be applied equally to each layer. Therefore, the UE can apply a transformation precoder to different DM-RS ports.

[0262] JPEG2025539005000011.jpg41170

[0263] The TPMI or SRI applied to the PUCCH DM-RS may be derived from information configuring the PUCCH resource. The TPMI or SRI applied to the PUCCH DM-RS may not be explicitly derived from scheduling information (e.g., scheduling DCI).

[0264] Method 5-9: The TPMI (or Tx beam) applied to the PUCCH DM-RS may be derived from the PUCCH resource, and the TPMI (or Tx beam) applied to the PUCCH DM-RS may not be explicitly indicated by the scheduling information.

[0265] If there are two or more pieces of spatial relationship information (or UL / split TCIs) referenced by the PUCCH resource, the base station can instruct the terminal to change / cancel some of the UL / split TCIs. According to technical specifications, when PUCCH repeated transmission is performed in the time domain, one or more UL / split TCIs to be applied sequentially can be instructed to the terminal. When STxMP PUCCH transmission is supported, the UL / split TCIs can be updated using the same signaling. The terminal can interpret the UL / split TCIs signaled by the base station as the UL / split TCIs to be applied to simultaneous PUCCH transmission.

[0266] 6. Method for deriving the STxMP UL coherence window

[0267] The UE can extend UL coverage using repeated transmission. The repeated transmission method will be described as STxMP PUSCH transmission or STxMP PUCCH transmission. The UL signal / channel can include at least PUSCH and PUCCH. The UL signal / channel can also refer to SRS.

[0268] The base station can select one Tx panel for the terminal and instruct the terminal to repeatedly transmit the UL signal / channel using the selected Tx panel. The base station can select a radio link with high quality. In this case, the effective code rate can be reduced.

[0269] Method 6-1: In the central area of ​​UL coverage, the terminal can transmit UL signals / channels based on the STxMP method. The terminal can assume that the STxMP UL signals / channels are not repeatedly transmitted. The STxMP UL signals / channels may refer to UL signals / channels based on the STxMP method.

[0270] The quality of a wireless link can vary significantly due to blockages. If the power (e.g., transmit power) of each Tx panel is controllable, a terminal can utilize two or more Tx panels simultaneously. A base station can instruct a terminal to repeatedly transmit an UL signal / channel. If the transmit power of a terminal located in the edge area of ​​UL coverage increases, the interference caused by the terminal's transmission can have a significant impact on neighboring base stations. Therefore, it is preferable for a terminal to maintain an appropriate transmit power while lowering the effective code rate.

[0271] Method 6-2: The terminal can receive scheduling information for repeated transmission of STxMP UL signals / channels.

[0272] The base station may transmit signaling (e.g., RRC signaling) to the terminal instructing the terminal to additionally perform DM-RS bundling while repeatedly transmitting the UL signal / channel. The terminal may confirm that the performance of DM-RS bundling is instructed by the base station's signaling (e.g., RRC signaling). If the DM-RS of the UL signal / channel(s) is received in multiple slots, the base station may perform joint channel estimation operations on the DM-RS. In this case, the gain of the channel estimation operation may be improved. To support this operation, the terminal may maintain coherence (e.g., power consistency and / or phase continuity) between slots in which the DM-RS is transmitted and received.

[0273] The time during which a terminal maintains coherence may be referred to as the nominal time domain window (TDW) and / or the actual TDW. An event may occur that prevents coherence from being maintained within the nominal TDW. Coherence may not be maintained after the event. The time before the event may be referred to as the actual TDW. Depending on the UE capability, the terminal may restart the actual TDW after the event. In this case, the terminal may maintain coherence even after the event.

[0274] Events can be classified into semi-static events and dynamic events. A semi-static event may refer to an event in which coherence cannot be maintained due to semi-statically reflected information (e.g., frequency hopping, TDD slot pattern, etc.) before the end of the nominal TDW. A dynamic event may refer to an event in which coherence cannot be maintained due to dynamically received information (e.g., group-common DCI, scheduling DCI) before the end of the nominal TDW.

[0275] The UE may assume that the actual TDW is generated by a static event (e.g., frequency hopping, a change in SRS resource set, a change in spatial relationship information, a change in UL / joint TCI, and / or a change in power control parameter(s)) rather than a dynamic event, and that coherence is maintained by the actual TDW. The following event(s) may be considered events for which coherence is not maintained: Depending on the UE capability, the actual TDW may not be generated after the event, or the actual TDW may be generated after the event depending on the UE capability.

[0276] A receiving operation on DL symbol(s) indicated by signaling (e.g., RRC signaling) between UL symbols can be considered an event. If a gap wider than 13 symbols (e.g., 11 symbols in the case of an extended cyclic prefix (CP)) occurs between two consecutive UL transmissions (e.g., PUSCH / PUCCH transmissions), the situation can be considered an event. If a gap wider than 13 symbols or 11 symbols occurs between two consecutive UL transmissions but another UL transmission is scheduled, the situation can be considered an event. The following situations may be considered as events: when PUSCH repetition type A is applied, when PUSCH repetition type B is applied, when TB is mapped to multiple slots (e.g., TB processing over multiple slots), when PUSCH transmission is dropped / cancelled due to UL prioritization / multiplexing procedures, when PUSCH transmission is dropped / cancelled due to slot pattern differences, and / or when PUSCH transmission is dropped / cancelled due to uplink cancellation indication (ULCI). The following situations may be considered as events: when two SRS resource sets are configured for two consecutive UL transmissions associated with PUSCH repetition type A / B, when PUSCH transmission is performed based on a codebook or non-codebook, and when the correlation relationship between the SRS resource sets changes; when spatial relationship information (or UL / transition TCI) for two consecutive PUSCH repetitions changes; or when power control parameters for two consecutive PUSCH repetitions change. The situation may be considered an event if a receive / apply operation on a TA command or TA value for timing alignment is performed, or if frequency hopping is performed.

[0277] The UE can determine the number of Tx panels (e.g., one Tx panel or two or more Tx panels) to be used for STxMP UL transmission based on the dynamic scheduling information. In this case, the UE can apply events that maintain coherence taking into account the determined Tx panel(s).

[0278] In an mDCI-based mTRP scenario, two TRPs can use independent scheduling information to instruct the UE to transmit UL signals / channel(s) (e.g., UL 1 and UL 2). In an sDCI-based mTRP scenario, the UE can transmit UL signals / channel(s) (e.g., UL 1 and UL 2) based on scheduling information received from one TRP.

[0279] UL1 and UL2 can be allocated so that they do not overlap in the time domain. UL1 and UL2 can be transmitted on the same Tx panel, or UL1 and UL2 can be transmitted on different Tx panels. In this case, a terminal can perform UL transmission on either UL1 or UL2, or can perform transmission on both UL1 and UL2.

[0280] Even if UL1 and UL2 do not overlap in the time domain, if an actual TDW for UL1 or UL2 is generated, the terminal can perform transmission to the Tx panel taking the actual TDW into account.

[0281] Repeated transmissions for UL 1 may be scheduled, and transmissions for UL 2 may be scheduled. The above situation may be considered in the following example.

[0282] FIG. 7 is a conceptual diagram illustrating a first embodiment of an event occurring in an STxMP transmission.

[0283] Referring to FIG. 7, a repeat transmission for UL 1 using two Tx panels (e.g., Tx panel 0 and Tx panel 1) may be scheduled to the terminal, and a transmission for UL 2 using Tx panel 1 may be scheduled to the terminal.

[0284] When DM-RS bundling is instructed to the terminal, the terminal may generate a nominal TDW while performing repeated transmission for UL 1. Depending on the events defined in the technical standard, the nominal TDW may be divided into two or more actual TDWs.

[0285] In the proposed method, the terminal can maintain one actual TDW. When an event occurs in one Tx panel, the event can be applied to all Tx panels. In another proposed method, when an event occurs in one Tx panel, the event can be applied to some Tx panel(s).

[0286] Method 6-3: The event can be applied commonly to all activated Tx panels.

[0287] In the embodiment of Figure 7, a nominal TDW may be generated for repeated transmissions for UL 1, and scheduling of UL 2 may be analyzed as an event. In this case, the actual TDW may be divided into two in Tx Panel 1. The base station may sequentially receive UL 1 transmission, UL 2 transmission, and UL 1 transmission, and may perform channel estimation operations independently for UL 1 transmission, UL 2 transmission, and UL 1 transmission. When repeated transmissions for UL 1 are performed, the terminal does not need to maintain coherence.

[0288] The actual TDW can be caused by power control as well as UL 2 scheduling, in which case the event can apply to all Tx panels.

[0289] According to Method 6-3, the implementation performance can be improved. If the actual TDW can be derived for each Tx panel, the channel estimation performance of the base station can be further improved.

[0290] Method 6-4: Events may be applied to some Tx panel(s).

[0291] In the example of Figure 7, the scheduling of UL 2 on Tx panel 0 may be analyzed as an event, but no event may occur on Tx panel 1. The terminal may not maintain coherence for UL 1 transmission on Tx panel 0, but the terminal may maintain coherence for UL 1 transmission on Tx panel 1. In other words, the terminal may manage the actual TDW per Tx panel. According to Method 6-4, the nominal TDW may be managed regardless of the Tx panel, and the event that generates the actual TDW may be managed per Tx panel.

[0292] In order for the terminal to manage two or more actual TDWs, a separate UE capability may be supported. Depending on the UE capability, the terminal can apply method 6-3 or method 6-4.

[0293] Method 6-5: Depending on the UE capabilities, the event analysis method can be derived differently.

[0294] 7. Uplink timing alignment method

[0295] In an mTRP scenario, the relative distance between the terminal and each TRP may be similar. Alternatively, the relative distance between the terminal and each TRP may be significantly different. In an mTRP scenario, this may be considered when the terminal is located in the central area of ​​communication coverage and / or when the communication coverage is not large and the absolute propagation delay is small. The terminal may assume one DL timing and UL timing. The timing may be the timing at which an inverse fast Fourier transform (IFFT) and / or an FFT is performed. The OFDM symbol boundary may be derived based on the timing.

[0296] FIG. 8 is a conceptual diagram illustrating a first embodiment of the timing alignment method.

[0297] Referring to Figure 8, the base station and the terminal can analyze slot n. The slot boundary of the base station may differ from the slot boundary of the terminal. Taking propagation delay into account, the DL timing and UL timing can be derived. The difference between the DL timing and the UL timing may be referred to as TA (timing advance).

[0298] In an mTRP scenario serving a wide area, a relatively large propagation delay can be taken into account, L1 / L2-based mobility functions can be supported, and inter-cell beam management can be supported. The relative propagation delay between TRPs can be large. In this case, the propagation delay can be longer than the CP of an OFDM symbol. In this case, the terminal can assume one or more DL timings and one or more UL timings. The assumptions can mean "an increase in the number of FFT / IFFT engines" and / or "faster execution time." Therefore, the actions (e.g., the assumptions) can depend on the UE capabilities.

[0299] Method 7-1: The terminal can assume one or more DL timings and one or more UL timings according to the UE capabilities.

[0300] FIG. 9 is a conceptual diagram illustrating a second embodiment of the timing alignment method.

[0301] Referring to FIG. 9, a terminal may have two DL timings and one TA. DL reference time may refer to DL timing. UL reference time may refer to UL timing. A terminal may derive DL timing from two or more TRPs. In other words, a terminal may determine DL timing for two or more Tx panels of the terminal. A TA may be derived based on the difference between DL timing 1 (e.g., DL reference time 1) and UL timing 1 (e.g., UL reference time 1) or the difference between DL timing 2 (e.g., DL reference time 2) and UL timing 2 (e.g., UL reference time 2). When two or more SRS resource sets are indicated to a terminal, the terminal may apply one TA to operate in STxMP mode, TDM mode, or sTRP mode. STxMP mode or TDM mode may be mTRP mode. In mTRP mode, a terminal may communicate with multiple TRPs. In sTRP mode, a terminal may communicate with one TRP.

[0302] Since the delay time between each TRP and the terminal may be different, it is preferable to apply a different TA to each TRP. Therefore, the terminal can manage two TAs. The base station can instruct the terminal to two TAGs (TA groups). The terminal can check the two TAGs instructed by the base station and perform closed-loop control using the TA command or TA value. The terminal can perform autonomous adjustment. The two TAGs can be associated with different TRPs.

[0303] The derived DL timing can be analyzed as a DL subframe boundary or DL ​​slot boundary, or the derived DL timing can be analyzed as a UL subframe boundary or UL slot boundary.

[0304] FIG. 10 is a conceptual diagram illustrating a third embodiment of the timing alignment method.

[0305] Referring to FIG. 10, a terminal may have one DL timing and two TAs. DL reference time may refer to DL timing. UL reference time may refer to UL timing. In an mTRP scenario, the terminal may operate in mDCI mode. The delay times for the TxP and the delay times for the RxP may be asymmetric. The terminal may operate in sDCI mode, receive data from one TxP, and transmit data to two or more RxPs. The terminal may derive (e.g., determine) DL timing from one TRP and derive (e.g., determine) UL timing 1 and UL timing 2 based on the DL timing. In other words, the terminal may derive TA1 and TA2. The base station may instruct two TAGs to the terminal. The terminal may check the two TAGs instructed by the base station and perform closed-loop control using the TA command (or TA value). The terminal may perform autonomous adjustment.

[0306] FIG. 11 is a conceptual diagram illustrating a fourth embodiment of the timing alignment method.

[0307] Referring to FIG. 11, a terminal may have two DL timings and two UL timings. The terminal may have two TAs. DL reference time may refer to DL timing. UL reference time may refer to UL timing. The embodiment of FIG. 11 may be a generalized embodiment of the embodiment of FIG. 7. TA1 and TA2 may be derived based on the difference between each DL timing and each UL timing. TA1 and TA2 may be signaled to the terminal. The base station may instruct the terminal to use two TAGs. The terminal may check the two TAGs instructed by the base station and perform closed-loop control using the TA command. The terminal may perform autonomous adjustment.

[0308] In an mTRP scenario, the terminal can operate in mDCI mode and separately manage the radio link between the TRP and the terminal's Tx panel and / or the radio link between the TRP and the terminal's Rx panel.

[0309] The UE may receive a contention free random access (CFRA) indication from the TRP (or base station) to determine UL timing. The CFRA indication may refer to a PDCCH order. The UE may receive the PDCCH order and transmit a physical random access channel (PRACH) preamble based on the PDCCH order. The PDCCH order may trigger the UE to perform an RA procedure. The PDCCH order may be DCI format 1_0. The DCI format 1_0 used for the PDCCH order may include a DCI format identifier, a frequency domain resource assignment (FDRA), a random access preamble index (RAPID), a UL / supplementary UL (SUL) indicator, an SS / PBCH index, a PRACH mask index, and / or reserved bits. The PDCCH order may also include a TA group (TAG) ID. If the PDCCH order is received in TRP 0, the TAG indicated by the TAG ID included in the PDCCH order may be associated with a TA between the TRP 0 and the UE. Alternatively, if a PDCCH order is received in TRP 0, the TAG indicated by the TAG ID included in the PDCCH order may be associated with the TA between the UE and TRP 1, not TRP 0. A PDCCH order may include two or more TAG IDs. In this case, the two or more TAG IDs may include a TAG ID for TRP 0 and a TAG ID for TRP 1. An initial TA may be derived based on a PRACH preamble. The initial TA may be managed in UL timing 2 separately from UL timing 1, which is under open-loop control.

[0310] The UE may use DL timing to derive UL timing for transmitting the PRACH preamble. When one DL timing is applied to the UE, the UE may assume TA2=0 and transmit the PRACH preamble. The UE may derive a PRACH preamble index, a PRACH mask, an SSB index, an additional PCI (physical cell identifier), etc. based on the PDCCH order. The additional PCI may be a PCI separate from the PCI of the serving cell. For example, if a PDCCH order is received at TRP0, the additional PCI included in the PDCCH order may correspond to TRP1 rather than TRP0. In this case, the UE may transmit the PRACH preamble at TRP1 indicated by the additional PCI included in the PDCCH order.

[0311] The DCI indicating a PDCCH order may include a separate field, and the separate field may indicate to a terminal whether a PCI included in the PDCCH order is an additional PCI. The separate field may be configured with 1 bit, and a first value of the separate field may mean that the PCI included in the PDCCH order is an additional PCI, and a second value of the separate field may mean that the PCI included in the PDCCH order is the PCI of a serving cell. Preferably, the terminal receives an indication or configuration of the PCI of the serving cell and the additional PCI through RRC signaling.

[0312] A PCI can be derived based on a bit indicated by a DCI indicating a PDCCH order, and a random access occasion resource that the terminal can select can be derived based on a combination of the derived PCI and an SSB block index.

[0313] The PRACH preamble may be transmitted based on DL timing determined based on the SSB received in TRP 1. As another example, if a PDCCH order is received in TRP 0 and an SSB index included in the PDCCH order corresponds to a specific SSB in TRP 1 rather than TRP 0, the UE may transmit the PRACH preamble to TRP 1 according to DL timing determined based on the specific SSB in TRP 1 indicated by the SSB index included in the PDCCH order.

[0314] The terminal may use DL timing reflected by TA1 (e.g., DL timing managed by TA1). Alternatively, the terminal may use new DL timing. The terminal may acquire TA2 (e.g., actual TA2) for TRP2 while tracking TA1 for TRP1.

[0315] Method 7-2: The terminal can assume TA2=0 based on the DL timing for the DL signal / channel received from the serving cell (or TRP1).

[0316] The base station may receive a PRACH preamble from the terminal, determine an initial TA2 based on the PRACH preamble, and transmit the initial TA2 to the terminal. The initial TA2 may represent the difference between DL timing 1 for TRP1 and UL timing 2 for TRP2. Therefore, the initial TA2 may differ from the actual TA2. To calibrate the difference between the initial TA2 and the actual TA2, a TA loop (e.g., a separate TAG for TRP2) managed by the base station may be used. Alternatively, if the UE capability allows the terminal to perform an FFT / IFFT operation more than once, the terminal may measure the difference between DL timing 1 and DL timing 2 and derive the actual TA2 based on the measured difference and the initial TA2. Even if the terminal does not support separate UE capability (e.g., UE capability supporting the performance of an FFT / IFFT operation more than once), the terminal may still utilize DL timing 2. In this case, the terminal can derive DL timing 2 by receiving SSB without receiving data (e.g., SIB, control information in CORESET, etc.) from TRP2.

[0317] When the sDCI mode is used in the mTRP scenario, method 7-2 can be applied. When the sDCI mode is used, the CORESET pool index may not be indicated to the terminal, in which case the terminal's operation may be the same as that using one CORESET pool index. In this case, the terminal can manage one DL reception timing. DL reception timing may mean DL timing.

[0318] When the mDCI mode is used in the mTRP scenario, method 7-2 can be applied. The base station can indicate a CORESET pool index to the terminal, and the terminal can check the CORESET pool index indicated by the base station. In this case, the terminal can manage (only) the DL reception timing associated with the first CORESET pool index. Therefore, the terminal can apply the DL reception timing derived from the first CORESET pool index without separate management of the DL reception timing associated with the second CORESET pool index.

[0319] If the UE capability supporting two or more FFT / IFFT operations is supported, DL timing 1 and DL timing 2 can be managed. In this case, the UE can consider the transmission reference of the PRACH preamble as DL timing 2. Even if a separate UE capability (e.g., a UE capability supporting two or more FFT / IFFT operations) is not supported, the UE can use DL timing 2. In this case, the UE can derive DL timing 2 by receiving SSB without receiving data (e.g., SIB, control information in CORESET, etc.) from TRP2.

[0320] Method 7-3: The terminal can assume TA 2=0 using the DL timing (e.g., DL timing 2) at which the SSB (and / or additional PCI) corresponding to the SSB index derived in the PDCCH order is received.

[0321] When the mDCI mode is used in the mTRP scenario, method 7-3 can be applied. The base station can indicate one or more CORESET pool indexes to the terminal, and the terminal can check one or more CORESET pool indexes indicated by the base station. In this case, the terminal can manage two or more DL reception timings. A CORESET pool index can correspond to each TRP. TRP1, which transmits a PDCCH order received by the terminal, can be different from TRP2, which receives a PRACH preamble transmitted by the terminal. Therefore, TA2 for transmitting a PRACH preamble can be the DL reception timing for TRP2. In other words, TRP1 can transmit a PDCCH order to the terminal, including an SSB index (or PCI for TRP2), which is information for a specific SSB of TRP2. The terminal can receive a PDCCH order from TRP1 and check the information elements included in the PDCCH order. If the SSB index included in the PDCCH order of TRP1 corresponds to a specific SSB of TRP2 or if the PCI included in the PDCCH order of TRP1 corresponds to TRP2, the terminal can transmit a PRACH preamble to TRP2 based on the DL timing measured based on the specific SSB of TRP2.

[0322] When two TAs are managed, the two TAs may be managed by separate TAGs. The TA between the terminal and TRP1 may be managed by TAG1, and the TA between the terminal and TRP2 may be managed by TAG2. The TA applied to the transmission of the UL signal / channel may be explicitly indicated to the terminal. Alternatively, the terminal may implicitly derive the TA applied to the transmission of the UL signal / channel. Generally, the terminal may derive (e.g., determine) DL timing 1, DL timing 2, UL timing 1, and / or UL timing 2.

[0323] Method 7-4: DCI scheduling UL signals / channels may include TAG ID or TAG information.

[0324] A separate field indicating the TAG ID may be included in the DCI, or the TAG ID may be derived based on an existing field or a combination of existing fields included in the DCI, or the TAG ID may be another identifier capable of distinguishing the TAG.

[0325] When the number of TAGs is limited to two, the TAG ID can be represented by one bit. For example, one bit (e.g., TAG ID) can be used to indicate one of two TAGs. If the TAG ID has two or three, one bit can be used to represent one TAG in the DCI. To support the above operation, the mapping relationship between the TAG ID and the TAG can be indicated or configured to the UE by RRC signaling.

[0326] The TAG ID may be included in a MAC CE including a TA command or a TA value. When a PRACH is transmitted in an RA procedure, the base station may transmit a RAR (random access response) including a TA command (or a TA value) and a TAG ID to the terminal. Alternatively, the base station may transmit a MAC CE including a "TA command and TAG ID" or a "TA value and TAG ID" to the terminal.

[0327] The RAR or MAC CE can contain information that can indicate a TAG. One bit can be additionally included in the RAR or MAC CE to indicate one of two TAGs.

[0328] When the mTRP mode is used, a contention free random access (CFRA) indication or a PDCCH order may be transmitted to the terminal via one TRP 0. In this case, the terminal may transmit a PRACH preamble to another TRP 1. In other words, the terminal may transmit a PRACH preamble to TRP 1 based on the CFRA indication or PDCCH order received via TRP 0. The CFRA configuration information or PDCCH order may be received via panel 0 of the terminal, and the PRACH preamble may be transmitted via panel 1 of the terminal.

[0329] The terminal can receive information (eg, RAR, MAC CE) including a TAC (TA command) (or TA value) and a TAG ID (or TAG identifier) ​​from TRP0 or TRP1.

[0330] Method 7-5: The terminal may receive information including a TAC (or TA value) and a TAG ID (or TAG identifier) ​​from TRP 0 (eg, the TRP that triggered the CFRA).

[0331] Method 7-6: The terminal can receive information including a TAC (or TA value) and a TAG ID (or TAG identifier) ​​from TRP1 (for example, the TRP that received the PRACH preamble).

[0332] When Method 7-5 is applied, the terminal can receive the information (e.g., TAC and TAG) from a UE-specific PDSCH. In other words, the terminal can acquire the information (e.g., TAC and TAG) from a PDSCH including an RAR. When Method 7-6 is applied, the terminal can acquire the information (e.g., TAC and TAG) from a PDSCH including an RAR. Considering beam correspondence, the terminal can derive a Tx beam corresponding to an Rx beam on which a DL signal / channel provided with qcl-typeD is received. In this case, the terminal can derive information on the beam but cannot confirm information on the TA. Therefore, the terminal may need the TRP, information corresponding to the TRP, a panel, and / or information corresponding to the panel. In this case, it is preferable that the base station indicates the DL signal / channel identifier and / or the UL signal / channel identifier together with the TAG ID to the terminal.

[0333] The base station can indicate the TCI state (or TCI state index) to the terminal through signaling (e.g., RRC signaling). In this case, the TCI state can include one or more TCIs. One TCI can include a DL signal / channel identifier or a UL signal / channel identifier providing qcl-type1 and / or qcl-type2. According to the proposed method, the terminal can derive a TAG ID (e.g., a TAG ID for TRP0 and / or a TAG ID for TRP1) along with a DL signal / channel (e.g., a DL signal / channel identifier) ​​or a UL signal / channel (e.g., a UL signal / channel identifier) ​​from the spatial relationship information or information indicating the TCI (e.g., UL TCI). The terminal can also derive reception timing (e.g., DL reception timing).

[0334] Method 7-7: When DL TCI is indicated, the receive timing for the DL signal / channel providing qcl-typeA or qcl-typeD and the DL signal / channel 1 to which DL TCI is applied may be assumed to be identical.

[0335] Method 7-8: When UL / Joint TCI (or SRI) is indicated, the TA or the group to which the TA belongs can be derived as well as information to generate the Tx beam from the DL signal / channel (e.g., the DL signal / channel identifier) ​​or the UL signal / channel (e.g., the UL signal / channel identifier).

[0336] When an UL signal / channel is referenced by a UL / split TCI, the transmission timing (e.g., UL timing) of the PUSCH and the UL signal / channel may be assumed to be the same for a PUSCH to which the UL / split TCI is applied. When a DL signal / channel is referenced by a UL / split TCI, the TRP transmitting the DL signal / channel and the TRP receiving the PUSCH may be expected to be the same for a PUSCH to which the UL / split TCI is applied. In this case, the UE may derive the Tx beam and / or transmission timing of the PUSCH using the DL signal / channel.

[0337] Although the above embodiments have been described as being applied to PUSCH transmission, the above embodiments may also be applied to PUCCH and / or SRS transmission.

[0338] The SRS resource set may be associated with the UL / joint TCI or SRI. In this case, the UE can reuse the TA or TAG of the SRS resource set. This operation may be applied when the UL signal / channel is referenced by the UL / joint TCI.

[0339] Methods 7-9: Two or more SRS resource sets indicated by the same serving cell may be associated with different TAGs.

[0340] When a DL signal / channel is referenced in the UL / connection TCI, other DL signals / channels referenced by the DL signal / channel can be derived. By repeating the above operation, an SSB can be derived. A TAG can be derived from the TRP transmitting the SSB. To support the above operation, a TRP identifier can be associated with the TAG. The base station can indicate the TRP identifier and / or TAG to the terminal through signaling (e.g., RRC signaling). The terminal can confirm the TRP identifier and / or TAG indicated by the base station.

[0341] Method 7-10: If a UL / Joint TCI referenced in the DL signal / channel is used, the TAG can be derived from the TRP carrying the DL signal / channel.

[0342] The CORESET pool index can be used in the TRP identifier.

[0343] 8. How to indicate UL gap for each Tx panel

[0344] Communication systems operating in FR2 can comply with maximum permissible exposure (MPE) regulations to control the RF exposure of terminals. In this case, power management (P-MPR) maximum power reduction (MPR) prediction can be difficult. Terminal operation needs to be improved to prevent radio link failures and / or connection releases due to temporary UL power adjustments of the terminal.

[0345] The terminal can report the P-MPR value to the base station using a power headroom report (PHR). For the proximity sensor to operate correctly, it may be necessary to generate and / or configure certain gaps in FR2 communication. An FR2 UL gap may be introduced for the proximity sensor to operate.

[0346] During FR2 communication (e.g., transmission using a beam in FR2), the terminal can use a proximity sensor to determine whether a human body is in proximity to the product. If the terminal does not have a proximity sensor, the terminal (e.g., the terminal's transmitter) can control the transmission power so that the average transmission power does not exceed a limit within a time window. This operation can satisfy RF exposure regulations. This operation can reduce the maximum transmission power of the terminal regardless of whether a human body is present near the terminal.

[0347] While many Tx panels precisely set the beam direction, proximity sensors can enable additional power adjustments when the human body is susceptible to RF exposure. When high-power devices, such as fixed wireless access (FWA) devices that use high transmit power, use proximity sensors, MPE regulations can be met without constant power changes. This can improve not only the device's coverage but also the user experience.

[0348] Calibrating a terminal in FR2 can be more difficult than calibrating a terminal in FR1. RF can have nonlinear characteristics due to rapid hardware temperature changes caused by high processing rates, phase noise caused by the use of wide bandwidths and / or high frequencies, etc.

[0349] To resolve the I / Q imbalance, a UL gap can be introduced. In this case, the I / Q imbalance can be resolved with low complexity. The UL gap can be utilized to estimate the LO (local oscillator) leakage and / or DC offset of the IF (intermediate frequency) mixer.

[0350] If FR2 single cell, F2 inter-band CA, and / or F2 intra-band are supported, the UE can support UL gaps. In this case, the UE can support at least one of gap pattern 1 or gap pattern 3 (e.g., UL MGP (measurement gap pattern) #1 or UL MGP #3). The UE can support different gap patterns (e.g., UL MGP #0 or UL MGP #2 in Table 8 below) depending on the UE capabilities. Table 8 below shows the UL gap patterns.

[0351] [Table 8]

[0352] A UL gap may contain logically consecutive UL slot(s). UL slot(s) (e.g., UL gap) may refer to UL slot(s) based on semi-static configuration. UL slot(s) (e.g., UL gap) may not refer to UL slot(s) containing UL symbols based on dynamic configuration. UGL (e.g., UL gap length) may be configured in ms. The number of UL slots included in a UL gap may vary depending on the SCS (subcarrier spacing). For UL MGP#0, UGL may be 1 ms, and if an SCS of 30 kHz is applied, the UL gap may contain two UL slots. The two UL slots included in the UL gap may not be (physically) consecutive.

[0353] Depending on the UE capability (e.g., tx-Support-UL-GapFR2), the UE can perform or not perform UL transmission in the UL slot(s) belonging to the UL gap. A UE that supports the UE capability (e.g., tx-Support-UL-GapFR2) can transmit UL signals / channels in the UL slot(s) belonging to the UL gap. A UE that does not support the UE capability (e.g., tx-Support-UL-GapFR2) cannot transmit UL signals / channels in the UL slot(s) belonging to the UL gap. Even if the UE capability (e.g., tx-Support-UL-GapFR2) is not supported, the UL signals / channels can be transmitted in the UL slot(s) belonging to the UL gap as an exception.

[0354] The UL signal / channel transmitted by the UE in the UL gap may include HARQ-ACK, CSI, SRS, and / or PUSCH (e.g., partial PUSCH). The partial PUSCH may be a configured grant (CG) PUSCH, Msg3 PUSCH, and / or MsgA payload. A UE that does not support the UE capability (e.g., tx-Support-UL-GapFR2) can transmit a CG PUSCH, Msg3 PUSCH, and / or MsgA payload, but cannot transmit a CG PUSCH, Msg3 PUSCH, and / or MsgA payload in the UL slot(s) belonging to the UL gap when dynamic scheduling is received. Therefore, the base station can determine that the UE will not transmit a UL signal / channel in the UL slot(s) (e.g., UL gap).

[0355] The base station can not schedule UL signals / channels in the UL gap. In the proposed method, the UL gap can be indicated per Tx panel.

[0356] Method 8-1: The base station can instruct the terminal to use two or more UL gaps. Each UL gap can have a different slot offset (or a different subframe offset). A UL gap pattern can correspond to one Tx panel.

[0357] The base station can configure two or more UL gap patterns for the terminal. The terminal can confirm two or more UL gap patterns configured by the base station. Correlation information between the UL gap pattern and the Tx panel, UL / joint TCI, and / or spatial relationship information can be indicated to the terminal. The UL gap pattern information can include UL signal / channel information. Alternatively, the UL signal / channel configuration information can include UL gap pattern information. Transmission of the UL signal / channel associated with the UL gap can be analyzed as being canceled. Alternatively, transmission of the UL signal / channel associated with the UL gap can be analyzed as being allowed.

[0358] The base station can configure one UL gap pattern for the terminal. The terminal can confirm one UL gap pattern configured by the base station. One UL gap pattern can have an additional slot offset (e.g., an additional subframe offset). The terminal can generate two or more UL gap patterns by applying an additional slot offset (e.g., an additional subframe offset) to one UL gap pattern. Each UL gap pattern can be associated with a Tx panel, UL / joint TCI, and / or spatial relationship information. Transmission of the UL signal / channel associated with the UL gap can be analyzed as being canceled. Alternatively, transmission of the UL signal / channel associated with the UL gap can be analyzed as being allowed.

[0359] 9. Power Headroom Reporting Method Considering DWS

[0360] The UE can report power headroom information to the base station. The base station can perform UL scheduling using the power headroom information of the UE. The PHR can be included in the MAC CE. In other words, the PHR can be included in the TB in the form of a MAC CE. The UE can transmit the MAC CE including the PHR on the PUSCH. The PHR can represent a quantized value for the difference between the maximum power and the power required for PUSCH transmission.

[0361] P CMAX、f、c (Maximum power) can be derived at frequency (f) of serving cell (c). P CMAX、f、c P may be a value to which MPR (maximum power reduction) is applied. The MPR may be determined taking into consideration the power class of the terminal, the PRB allocation in which the PUSCH is scheduled, the modulation order of the PUSCH, and / or the waveform. CMAX、f、c In addition to the MPR, A (additional)-MPR and / or P (power management)-MPR may be taken into account to determine the MPR.

[0362] The power required for PUSCH transmission can be divided into the power of PUSCH transmission scheduled in the serving cell and the power of PUSCH transmission not scheduled in the serving cell. When a terminal supporting CA and / or DC performs simultaneous transmission, a PHR for PUSCH transmission not scheduled in the serving cell can be derived to inform the base station of the terminal's power headroom.

[0363] JPEG2025539005000013.jpg76170

[0364] The PHR may be triggered by conditions defined in technical standards, such as when a timer expires, when the PHR is (re)configured by signaling (e.g., RRC signaling), when an SCell is activated, when an SCG (secondary cell group) is activated, and / or when a PSCell is added.

[0365] The timer may be a prohibit timer and / or a periodic timer. The prohibit timer may be used to distribute the PHR over time so that it is not triggered frequently. The periodic timer may be used to periodically trigger the PHR. Other conditions may be analyzed as various events related to changes in the status of the serving cell.

[0366] Two PHR formats may exist. For example, PHR formats may be classified into a multiple entry PHR format and a single entry PHR format. twoPHRMode may be configured. When a UE performs PUSCH repeated transmission in an mTRP scenario, power control for each radio link may be performed separately because fading differs between radio links. In this case, a PHR for each radio link may be required, and twoPHRMode may be configured to support this operation.

[0367] When a multiple entry PHR format is used (e.g., when multiplePHR is set to true and is indicated to the terminal), PHRs for all serving cells configured to the terminal can be derived. When twoPHRMode is indicated to the terminal, the terminal can derive two PHRs for one serving cell. When twoPHRMode is not indicated to the terminal, the terminal can derive one PHR for one serving cell.

[0368] When a single-entry PHR format is used (e.g., when the use of a multiple-entry PHR format is not indicated), a PHR related to the PCell can be derived. When twoPHRMode is indicated to the UE, the UE can derive two PHRs for the PCell. When twoPHRMode is not indicated to the UE, the UE can derive one PHR for the PCell.

[0369] 12 to 18 may illustrate a PHR MAC CE. The PHR MAC CE may be a MAC CE that includes a PHR.

[0370] FIG. 12 is a conceptual diagram illustrating a first embodiment of a single-entry PHR MAC CE.

[0371] Referring to FIG. 12, R may represent a reserved bit. R may be fixed to 0. The size of the power headroom (PH) may be 6 bits. The PH level may be divided based on a predefined criterion.

[0372] P may be interpreted differently depending on whether mpe-Reporting-FR2 is configured. If mpe-Reporting-FR2 is configured, the serving cell operates in FR2, P-MPR is applied, and P-MPR is smaller than P-MPR_00, P may be expressed as 0. If the above condition(s) are not met, P may be expressed as 1. P-MPR_00 may be a value derived separately based on technical specifications. If P-MPR is applied to meet MPE (maximum permissible exposure) requirements, P-MPR_00 may be used. If mpe-Reporting-FR2 is not configured or the serving cell operates in FR1, P may indicate whether power backoff occurs to support power management. If power backoff occurs, P may be expressed as 1. If power backoff does not occur, P may be expressed as 0.

[0373] P CMAX、f、c may refer to the value used to derive the PH. The PH level may be quantized according to a predefined criterion.

[0374] The MPE can be interpreted differently depending on whether mpe-Reporting-FR2 is configured. If mpe-Reporting-FR2 is configured, the serving cell operates in FR2, and P is represented by 1, the MPE can indicate the power backoff applied to satisfy the MPE request. The MPE can be represented by an index according to a predefined criterion. If mpe-Reporting-FR2 is not configured or the serving cell operates in FR1, and P is represented by 0, the MPE can be represented by R.

[0375] The multi-entry PHR format can be illustrated in FIGS.

[0376] FIG. 13 is a conceptual diagram illustrating a first embodiment of a multi-entry PHR MAC CE, and FIG. 14 is a conceptual diagram illustrating a second embodiment of a multi-entry PHR MAC CE.

[0377] 13 and 14, the multi-entry PHR format can have a variable size. The multi-entry PHR format includes a bitmap, a Type 2 PH field, and a P for SpCell. CMAX、f、c "Octet containing field" and "Type 1 PH field and P for PCell CMAX、f、c The multi-entry PHR format may contain one or more Type 1 PH fields (or one or more Type 3 PH fields) in the order of the serving cell index (ServCellIndex) and the PHR field for the serving cell. CMAX、f、c It may contain octet(s) that contain fields.

[0378] The size of the bitmap may be 8 bits or more. In the embodiment of Figure 13, if 8 or fewer serving cells are configured (e.g., if the maximum value of ServCellIndex is 8 or less), the bitmap may be represented by one octet. In the embodiment of Figure 14, if more than 8 serving cells are configured, the bitmap may be represented by four octets.

[0379] To determine the PH (e.g., actual PH or reference PH) derived for an activated serving cell, the "PUSCH processing time" and / or the "reception time indicated to the terminal by DCI or CG (configured grant)" may be taken into account.

[0380] For band combinations that do not support dynamic power sharing, the PH field and P CMAX、f、cThe octet(s) including the field may be omitted in a multiple-entry PHR MAC CE. Exceptionally, information for PCells belonging to other cell groups (or other MAC entities) may not be omitted in a multiple-entry PHR MAC CE. CMAX、f、c can be determined.

[0381] If a PH field exists for the serving cell (i) indicated by ServCellIndex, C i may be set to 1. If the PH field for the serving cell (i) indicated by ServCellIndex is not present, C i can be set to 0.

[0382] V can indicate an actual PH or a reference PH. If information for PUSCH is transmitted in Type 1 PH, V can be represented as 0. If a reference PH is used, V can be represented as 1. If information for PUCCH is transmitted in Type 2 PH, V can be represented as 0. If a reference PH is used, V can be represented as 1. If information for SRS is transmitted in Type 3 PH, V can be represented as 0. If a reference PH is used, V can be represented as 1. V set to 0 indicates that PUCCH is not included in the multiple entry PHR MAC CE. CMAX、f、c A V value of 1 may mean that there is an octet containing the PHR MAC CE and the MPE fields. CMAX、f、c This may mean that the octet containing the field and the MPE field is omitted.

[0383] If an MPE occurs, the MPE resource may be specified separately. In this case, an improved PHR may be applied. The improved PHR may be illustrated in Figures 15 to 17.

[0384] FIG. 15 is a conceptual diagram illustrating a first embodiment of an improved single-entry PHR MAC CE.

[0385] Referring to FIG. 15, when the improved single-entry PHR MAC CE is considered, B i and resources i can be considered additionally. The base station can instruct the UE to use mpe-ResourcePoolToAddModList through signaling (e.g., RRC signaling), and SSB or CSI-RS can be represented by an index with a size of 6 bits. When MPE occurs, the resource pool for SSB or CSI-RS is used in the candidate beam. i can be used.

[0386] 16a and 16b are conceptual diagrams illustrating a first embodiment of an improved multi-entry PHR MAC CE, and FIGS. 17a and 17b are conceptual diagrams illustrating a second embodiment of an improved multi-entry PHR MAC CE.

[0387] With reference to Figures 16a, 16b, 17a, and 17b, an improved multi-entry PHR MAC CE can be considered. A first embodiment of the improved multi-entry PHR MAC CE can include the information elements (e.g., octets) shown in Figure 16a and the information elements (e.g., octets) shown in Figure 16b. The last information element (e.g., last octet) shown in Figure 16a can be continuous with the first information element (e.g., first octet) shown in Figure 16b. A second embodiment of the improved multi-entry PHR MAC CE can include the information elements (e.g., octets) shown in Figure 17a and the information elements (e.g., octets) shown in Figure 17b. The last information element (e.g., last octet) shown in Figure 17a can be continuous with the first information element (e.g., first octet) shown in Figure 17b.

[0388] The improved multiple-entry PHR MAC CE may be applied when the UE performs CA operation. If the largest ServCellIndex value set in the UE is equal to or less than 8, the improved multiple-entry PHR MAC CE shown in Figure 16 may be applied. If the largest ServCellIndex value set in the UE exceeds 8, the improved multiple-entry PHR MAC CE shown in Figure 17 may be applied.

[0389] When two UL carriers are configured for a terminal in one serving cell, a Type 1 PHR and / or a Type 3 PHR can be determined in the serving cell. The Type 1 PHR and the Type 3 PHR can have the same format (e.g., actual format or reference format). Alternatively, the Type 1 PHR and the Type 3 PHR can have different formats. If the Type 1 PHR and the Type 3 PHR have the same format, the Type 1 PHR can be derived. If the Type 1 PHR and the Type 3 PHR have different formats, the PHR having the actual format can be derived.

[0390] According to the embodiments of FIGS. 12 to 17, one PH for a PHR MAC CE can be generated in one serving cell.

[0391] The UE can repeatedly transmit the PUSCH for two TRPs. In this case, Figures 18 to 20 can be taken into consideration.

[0392] FIG. 18 is a conceptual diagram illustrating a first embodiment of an improved single-entry PHR MAC CE for multiple TRPs.

[0393] Referring to FIG. 18, an improved single-entry PHR MAC CE can be supported by two TRPs. A PHR including two PHs can be generated for one serving cell. A base station can configure SRS resource sets for two or more identifiers (ids) to a terminal through signaling (e.g., RRC signaling). Two or more identifiers (ids) can be distinguished from each other. A terminal can select SRS resource sets for the two identifiers and derive a PH for the selected SRS resource set. In the embodiment of FIG. 18, PH 1 can be derived from the SRS resource set associated with the lower of the two identifiers, and PH 2 can be derived from the SRS resource set associated with the higher of the two identifiers. P CMAX、f、c may mean a value that is commonly applied to PH1 and PH2.

[0394] FIG. 19 is a conceptual diagram illustrating a first embodiment of an improved multi-entry PHR MAC CE for multiple TRPs, and FIG. 20 is a conceptual diagram illustrating a second embodiment of an improved multi-entry PHR MAC CE for multiple TRPs.

[0395] 19 and 20, the improved multi-entry PHR may be supported by two TRPs. The improved multi-entry PHR may be applied when the UE performs CA operation. The embodiment of FIG. 19 may be applied when the largest ServCellIndex value configured in the UE is equal to or less than 8. The embodiment of FIG. 20 may be applied when the largest ServCellIndex value configured in the UE exceeds 8. When one SRS resource set is indicated to the UE in the serving cell, some octet(s) may be omitted in the improved multi-entry PHR MAC CE. For example, optional information elements (e.g., optional fields, optional octets) may be omitted in the improved multi-entry PHR MAC CE.

[0396] If the PUSCH waveform is changed, CMAX、f、c can be modified, and the modified P CMAX、f、c may be applied. P CMAX、f、cThe reason for changing the PHR is that the MPR, A-MPR, and / or P-MPR change depending on the PUSCH waveform, modulation order, band combination, and / or PRB allocation. Therefore, scheduling to change the waveform can be a condition for triggering the PHR.

[0397] Method 9-1: When scheduling information for the initial transmission of a TB is received, scheduling to change the waveform can be considered in the triggering conditions of the PHR.

[0398] When a base station schedules a PUSCH to a terminal and a TB is retransmitted, the retransmission TB may be the same as the previous TB. In this case, even if a PHR is triggered, the PHR may not be reflected in TB transmission (e.g., TB retransmission). If decoding of an ultra-high-transmission TB fails, the base station may transmit a TB retransmission instruction and a waveform change instruction to the terminal. In this case, if method 9-1 is applied, the ultra-high-transmission TB may include the triggered PHR.

[0399] A method of reporting one PH from one serving cell can be considered. When scheduling information is received from the serving cell, the terminal can derive a PHR based on the waveform indicated by the scheduling information. The above operation can be generalized as follows. For example, one PH (or two PHs in a multiple TRP scenario) can be generated in the serving cell. Alternatively, a PHR can be generated for each serving cell. The terminal can transmit the PH or PHR on the PUSCH.

[0400] Method 9-2: The terminal can report one PH. The terminal can derive a PHR that applies the actual format by assuming the waveform indicated by the scheduling information.

[0401] Reported pH and P CMAX、f、c Other fields, including , may be included in a single PHR. In this case, more than one PHR may be multiplexed. Alternatively, PH and P CMAX、f、cOther fields may be included in a PHR, including:

[0402] It is preferable that the base station triggers the PHR of the CP-OFDM-based PUSCH and the PHR of the DFT-s-OFDM-based PUSCH without changing the waveform of the PUSCH. The base station can receive two PHRs for one serving cell and determine whether to perform a waveform change operation based on the two PHRs.

[0403] Method 9-3: The UE can report two PHs, each generated assuming a different waveform available in the same serving cell (or UL BWP).

[0404] PH can be derived for each waveform. For a reference waveform, an actual format-based PH can be derived. For other waveforms, a reference format-based PH can be derived. The reference waveform can be a waveform associated with the UL BWP. Alternatively, the reference waveform can be indicated by RRC signaling.

[0405] If the PH is derived for each waveform, the actual format or the reference format can be applied to all PH.

[0406] If PH is derived for each waveform, scheduling information may not be valid for the waveform. Scheduling, which is not assumed in DFT-s-OFDM, can allocate CP-OFDM-based PUSCH. Since a multi-carrier waveform is used in the case of CP-OFDM, frequency resources including discontinuous PRBs can be allocated. Since a single-carrier waveform is used in the case of DFT-s-OFDM, frequency resources including contiguous PRBs can be allocated. Since transmission for a single layer is performed in the case of DFT-s-OFDM, combinations that are not allowed by DM-RS port mapping may be valid combinations in CP-OFDM.

[0407] Waveforms may be classified as waveforms indicated by scheduling information (eg, actual waveforms) and waveforms that are substituted (eg, assumed waveforms or alternative waveforms).

[0408] If invalid scheduling information is indicated for an alternative waveform, the UE may perform a PH (e.g., PHR) generation operation for the actual waveform. The generation operation may include the UE recalculating all values ​​constituting the PHR. The UE may not recalculate the PH (e.g., PHR) for the alternative waveform. The UE may transmit the PH (e.g., PHR) for the alternative waveform via a PUSCH. The UE may not perform a new calculation for the PH (e.g., PHR) for the alternative waveform. The UE may not transmit the PH (e.g., PHR) for the alternative waveform via a PUSCH.

[0409] Method 9-4: Even if the scheduling information for the alternative waveform is not valid, the PH (eg, PHR) for the alternative waveform may be transmitted on the PUSCH.

[0410] The terminal may not perform new calculations for the alternative waveform. Therefore, the base station may consider the PH (e.g., PHR) to be a dummy. The terminal may transmit an unupdated PH (e.g., PHR). Alternatively, the terminal may consider an unupdated PH (e.g., PHR) to be reserved. Although the terminal may transmit unnecessary payload, processing may be simpler because the base station considers the size of the PHR MAC CE to be constant.

[0411] Method 9-5: If the scheduling information for the alternative waveform is not valid, the PH (eg, PHR) for the alternative waveform may be dropped in the PUSCH.

[0412] Invalid PHs (e.g., PHRs) may not be included in the PUSCH. Since scheduling information is transmitted via DCI, the MAC layer may not know the scheduling information. Therefore, a separate bit may be introduced into the improved PHR to distinguish between legacy PHs (e.g., PHRs) and improved PHRs.

[0413] One bit for each serving cell can be added to the PHR, which can indicate whether a PH exists for an alternative waveform, or whether a PH is updated for an alternative waveform.

[0414] Method 9-6: When a bit of a PHR has a first value, the bit having the first value may mean that a PH for an actual waveform (e.g., a legacy PH) is included in the PHR. When a bit of a PHR has a second value, the bit having the second value may mean that a PH for an alternative waveform is additionally included in the PHR.

[0415] Method 9-7: When a bit of a PHR has a first value, the bit having the first value may mean that an updated PH for an alternate waveform is included in the PHR. When a bit of a PHR has a second value, the bit having the second value may mean that an update of the PH (e.g., PHR) for an alternate waveform is not required.

[0416] The UE may derive a PH for a PUSCH based on CP-OFDM and DFT-s-OFDM, respectively. A PH for a CP-OFDM-based PUSCH may be referred to as a PH(CP-OFDM). A PH for a DFT-s-OFDM-based PUSCH may be referred to as a PH(DFT-s-OFDM). When one PHR includes a PH(CP-OFDM) and a PH(DFT-s-OFDM), the PH(CP-OFDM) and the PH(DFT-s-OFDM) may be arranged in a predefined order within one PHR. The predefined order may refer to the order in which the PH(CP-OFDM) and the PH(DFT-s-OFDM) are included in an octet. The predefined order may refer to the order of the octets belonging to the PHR.

[0417] The order of PH (CP-OFDM) and PH (DFT-s-OFDM) may be determined based on signaling (e.g., RRC signaling). The base station may use signaling (e.g., RRC signaling) to instruct the UE on the waveform associated with the UL BWP. In this case, information on the waveform associated with the UL BWP (e.g., PH) may be placed earlier or later in the PHR.

[0418] The PH for the waveform (eg, actual waveform) applied to the scheduled PUSCH may be placed earlier or later in the PHR.

[0419] Method 9-8: In Method 9-3, the order (e.g., placement order) of PH (CP-OFDM) and PH (DFT-s-OFDM) can be determined based on UL BWP. Alternatively, in Method 9-3, the order (e.g., placement order) of PH (CP-OFDM) and PH (DFT-s-OFDM) can be derived from the scheduling DCI.

[0420] For PHR containing two PHs, P CMAX、f、c can be generated for each PH, or for a PHR containing two PHs, one P CMAX、f、c can be applied, and one P CMAX、f、ccan be included in the PHR. For example, if PH(CP-OFDM) and PH(DFT-s-OFDM) are derived using the actual format, P CMAX、f、c can be derived based on other values. In this case, P for each PH CMAX、f、c PHRs including may be considered.

[0421] Method 9-9: P for each pH in Method 9-3 CMAX、f、c may be included in the PHR.

[0422] To reduce the number of octets contained in the PHR, the terminal CMAX、f、c can be included in the PHR, and P for other PHs CMAX、f、c It is possible to distinguish between cases where the actual format is considered and cases where the reference format is considered.

[0423] When the actual format is taken into consideration, different P CMAX、f、c For example, the reference PH may be PH(CP-OFDM). CMAX、f、c can be included in the PHR. PH(DFT-s-OFDM) can be included in other P CMAX、f、c However, PH(DFT-s-OFDM) may be omitted in the PHR. In this case, PH(CP-OFDM) may be included in the PHR. The base station calculates PH(CP-OFDM) and P CMAX、f、c The path loss can be estimated using the path loss and PH(DFT-s-OFDM), and the derivable P based on DFT-s-OFDM can be calculated using the path loss and PH(DFT-s-OFDM). CMAX、f、c The above operation is performed when the reference PH is PH(DFT-s-OFDM). CMAX、f、c can be used to derive

[0424] When the reference format is taken into account, the same value can be derived for all PHs. In this case, one PH can be included in the PHR. Alternatively, PHs with the same value can be included in the PHR. In other words, PHs with the same value in the PHR can be duplicated.

[0425] Method 9-10: P for one pH in Method 9-3 CMAX、f、c may be included in the PHR.

[0426] A PH to which an actual format is applied in a serving cell to which a PUSCH is transmitted can be derived. A PH to which a reference format is applied in a serving cell to which a PUSCH is not transmitted can be derived. When a reference format is applied, PRB allocation may not be derived, and MPR / A-MPR / P-MPR=0 can be considered, and P CMAX、f、c To derive PH with more information for the unscheduled PUSCH, a virtual transmission format negotiated between the terminal and the base station may be necessary.

[0427] Methods 9-11: The terminal can derive PH by applying a reference format based on a hypothetical transmission hypothesis.

[0428] A transmission assumption may refer to an allocation of resources that includes at least a specific PRB allocation, a specific modulation order, and a specific waveform.

[0429] According to the technical standard, to derive PH based on the reference format, the amount of resource allocation may be minimized, and a transmission hypothesis without waveform characteristics may be applied. Therefore, it is preferable that the base station transmits an instruction to apply a new transmission hypothesis to the terminal using signaling (e.g., RRC signaling). The terminal can apply the new transmission hypothesis based on the instruction from the base station. The new transmission hypothesis may have a resource allocation defined in the technical standard. The new transmission hypothesis may mean the allocation of specific resources indicated by signaling (e.g., RRC signaling).

[0430] According to another method, the terminal can use a virtual transmission hypothesis and apply the resource allocation of another serving cell where scheduling occurs. Since the terminal transmits a PUSCH to at least one serving cell, the terminal can transmit a PHR to the base station. Based on the PUSCH resource allocation, the PHR and PHR of the serving cell are CMAX、f、c The actual format for determining the UE number may be applied. The reference format for other serving cells may be applied.

[0431] Depending on the waveform, it may be necessary to generate more than one PH for the serving cell. In this case, the terminal can generate PH and P by applying the resource allocation of other serving cells where scheduling occurs. CMAX、f、c When scheduling occurs in multiple other serving cells, the terminal can select one of the multiple other serving cells, and PH and P CMAX、f、c The resource allocation of the selected serving cell can be applied to derive . For example, the terminal can select a serving cell having the largest or smallest identifier based on ServCellIndex from among multiple other serving cells.

[0432] Method 9-12: The terminal allocates resources of other serving cells where scheduling has occurred, thereby allocating PH and P for the serving cell where scheduling has not occurred. CMAX、f、c can be derived.

[0433] The base station can instruct the terminal to perform a method for deriving a PH based on the reference format. The terminal can perform the "method for deriving a PH based on the reference format" instructed by the base station.

[0434] Method 9-13: The base station may indicate a scheme for the reference format to the terminal through signaling (e.g., RRC signaling). The terminal may confirm a scheme for the reference format indicated by the base station signaling.

[0435] The base station can set twoPHRMode to the terminal. When twoPHRMode is set to the terminal, the terminal uses two PHs and one PHR for the serving cell. CMAX、f、c In order to compensate for the path loss during the PUSCH repetitive transmission, the UE can transmit two PHs to the base station. According to Method 9-3, the PHs according to the waveform can be used as PHRs. According to Method 9-10, the UE can transmit two PHs according to different waveforms. CMAX、f、c Even if two PHs are derived using CMAX、f、c According to the constraint, the terminal can transmit a PHR including P for the reference waveform based on a predefined rule between the terminal and the base station. CMAX、f、c A PHR including the above can be transmitted.

[0436] If scheduling does not occur in the serving cell, the terminal can derive a PH based on the reference format. In this case, it is preferable not to utilize a PH that does not reflect waveform characteristics. According to methods 9-13, the terminal can identify a method for a reference format indicated by base station signaling (e.g., RRC signaling). The terminal can generate a PH by applying resource allocation and transmission assumptions of another serving cell. Alternatively, the terminal can generate a PH by applying a separately indicated resource allocation or a predefined resource allocation.

[0437] 10. Multi-cell scheduling method and cross-carrier scheduling method considering DWS

[0438] One DCI format can contain scheduling information for two or more serving cells. For example, DCI formats 1-3 can be used for downlink communication for two or more serving cells, and DCI formats 0-3 can be used for uplink communication for two or more serving cells.

[0439] For convenience of explanation, the DCI field may be divided into a Type-1 field, a Type-2 field, a Type-3 field, etc. The Type-1 field may be classified into a Type-1A field, a Type-1B field, and a Type-1C field. In other words, the Type-1 field may include at least one of a Type-1A field, a Type-1B field, or a Type-1C field. The Type-1A field may represent common information for all serving cells to be scheduled. The Type-1B field may be a joint indicator. The Type-1C field may represent information for one serving cell among the serving cells to be scheduled.

[0440] The Type-2 field can be interpreted as an individual field (e.g., individual information) for each scheduling serving cell. Alternatively, the Type-2 field can be interpreted as an individual field for each subgroup of scheduling serving cell(s). In this case, the Type-2 field can be interpreted as common information for serving cells belonging to the subgroup. The Type-3 field can be interpreted as common information or individual information for each serving cell or subgroup to be scheduled.

[0441] Although DL DCI formats (e.g., DL-related DCI formats) and UL DCI formats (e.g., UL-related DCI formats) may include different fields, the fields in DL DCI formats and UL DCI formats may be divided into Type-1A fields, Type-1B fields, Type-1C fields, Type-2 fields, and Type-3 fields.

[0442] The Type-1A field may include at least one of an identifier for the DCI format, a downlink assignment index, a TPC for the scheduled PUCCH, a PUCCH resource indicator, a PDSCH-to-HARQ timing indicator, a one-shot HARQ-ACK request, a BWP indicator, a VRB-to-PRB mapping, a PRB bundling size indicator, a frequency hopping flag, an open-loop power control parameter set indicator, a DMRS sequence initialization, an enhanced Type-3 codebook indicator, a HARQ-ACK retransmission indicator, a PUCCH cell indicator, a priority indicator, ChannelAccess-Cpext, ChannelAccess-Cpext-CAPC, or a beta_offset indicator.

[0443] The Type-1B field may include at least one of a rate matching indicator, a ZP (zero power) CSI-RS trigger, a TCI, an SRS request, or an SRS offset indicator.

[0444] The Type-2 field may include at least one of a TB-specific NDI (new data indicator), a TB-specific RV (redundancy version), an MCS, an HPN (HARQ process number), an FDRA (frequency domain resource assignment), a TPC command for the scheduled PUSCH, or a PTRS-DMRS association.

[0445] The Type-3 field may contain at least a CSI request.

[0446] Fields that can be set in the Type-1A field and / or Type-2 field may include at least one of antenna port(s), precoding information and number of layers, SRS resource indicator (SRI), or UL / joint TCI.

[0447] The index(es) of the serving cell(s) reflecting the scheduling information may be indicated by one field or a combination of two or more fields in the DCI format. The base station may notify the UE of the index corresponding to the serving cell using signaling (e.g., higher layer signaling). The UE may check the index corresponding to the serving cell indicated by the base station. The higher layer signaling may include RRC signaling.

[0448] The serving cell index can be indicated by a two-step procedure. For example, the base station can indicate a set of serving cells to the terminal using signaling (e.g., higher layer signaling), and can indicate to the terminal which index corresponds to one serving cell or one or more serving cells in the serving cell set using signaling (e.g., higher layer signaling). A scheduled cell set indicator can refer to a set of serving cells, and a scheduled cell indicator can refer to one or more serving cells belonging to the serving cell set.

[0449] When all serving cells are activated, the DCI format can be used for scheduling for an active BWP. Some of the serving cells configured or indicated to the UE can be deactivated. Serving cell deactivation can be indicated by MAC CE, and the serving cell set and / or serving cell index can be indicated by signaling (e.g., RRC signaling). If the serving cell index is always indicated only by the combined index, scheduling information for deactivated serving cells can be indicated. Since scheduling information can be applied to activated serving cells, a method for solving this problem is needed.

[0450] Method 10-1: The terminal can assume that all serving cells scheduled by one DCI format are in an active state.

[0451] The UE may consider that a DCI format including scheduling information for all serving cells is received when all serving cells are in an activated state. If any serving cell cannot be indicated using a serving cell set and a serving cell index, the scheduling information may be scheduling information for serving cells including a deactivated serving cell.

[0452] To prevent this situation from occurring, the fields indicating the serving cell set and serving cell index may be set sufficiently large. In this case, the size of the DCI may increase. Increasing the size of the DCI may cause other problems. If the scheduling information is invalid, a procedure to be performed by the UE may be suggested.

[0453] Method 10-2: The UE may reflect scheduling information to activated serving cell(s) among the scheduled serving cells, and may not reflect scheduling information to deactivated serving cell(s).

[0454] Fields including the DWS field may be included in the scheduling information. Field(s) included in the scheduling information may not be supported by some serving cell(s) and / or some BWP(s). The following method may be applied to other field(s) (e.g., other information) as well as the DWS field.

[0455] The DCI format including the DWS field can be configured or indicated to the UE in units of BWP. When multi-cell scheduling information is considered, the DWS field can be parsed if the DWS function is supported in the UL BWP of each scheduled serving cell.

[0456] The DCI (e.g., DCI format) may include scheduling information for multiple serving cells. The scheduling information may include a DWS field. In this case, the UE may parse the DWS field in units of BWP.

[0457] For ease of explanation, the scheduling serving cell (e.g., serving cell 0, the serving cell where the DCI is received) and the scheduled serving cell may be distinguished. If the DL BWP is not changed in serving cell 0, the CORESET and search space set are not changed, and therefore the DCI format may not be changed. The UL BWP in the scheduled serving cell may be changed according to the scheduling information, and this operation may mean enabling / disabling the DWS function.

[0458] The DWS field of each scheduled serving cell may be included in the DCI. In this case, the DWS function of each scheduled serving cell may be controlled by serving cell 0. Among the active UL BWPs of the serving cell, there may be active UL BWPs in which the DWS function is not configured or indicated. In this case, the UE may ignore the information (e.g., the DWS field).

[0459] Method 10-3: If the DWS function is not configured in the active UL BWP of a serving cell among the serving cells to be scheduled, the DWS information (e.g., the value of the DWS field) for the active UL BWP of a serving cell indicated by the scheduling information may be ignored.

[0460] The DWS fields (e.g., DWS information) for BWPs for which DWS functionality is configured or indicated may not be included in the scheduling information, in which case a method for deriving the DWS information may be necessary.

[0461] Method 10-4: "When the DWS function for the active UL BWP of a serving cell among the serving cells to be scheduled is configured but the scheduling information does not include a DWS field for the active UL BWP of the serving cell," the value of the DWS field for the active UL BWP of the serving cell (e.g., the waveform indicated by the DWS field) may be interpreted as a specific value (e.g., 0 or 1), a value set (or indicated) by signaling (e.g., higher layer signaling) taking the situation into consideration, or a waveform associated with the active UL BWP.

[0462] The proposed method can be applied not only to multi-cell scheduling but also to cross-carrier scheduling. For example, in cross-carrier scheduling, fields (e.g., DWS fields) for all BWPs of all serving cells to be scheduled can be included in the scheduling information (e.g., DCI). Some of these fields can indicate information that is not supported in the active BWP to the UE. When method 10-3 is applied, the UE can ignore the information (e.g., information that is not supported in the active BWP) and can analyze the scheduling information using only valid information.

[0463] For another example, considering a group of serving cells to be scheduled, one DWS field (e.g., a DWS field for a group of serving cells) may be included in the scheduling information. The group of serving cells may be referred to as a serving cell group. A value of the DWS field may indicate one waveform in the active UL BWP of the serving cell(s) belonging to the serving cell group. The serving cell group may be the same as or different from the serving cell set indicated by the scheduling information. If the serving cell group and the serving cell set are different, the base station may indicate the serving cell group to the terminal using signaling (e.g., higher layer signaling).

[0464] Since serving cells aggregated to a terminal are not always located in one TRP (or base station, antenna site), a serving cell group may be introduced. To reduce PAPR / IMD (intermodulation distortion) and increase the PUSCH coverage area, the DWS function may be configured or indicated for each UL BWP. It is preferable to consider serving cells belonging to the same TRP and / or UL BWPs associated with the same TRP so that large-scale fading is shared.

[0465] Method 10-5: A serving cell group (or carrier group, BWP group) in which DWS information (e.g., DWS field) is shared can be introduced, and the base station can indicate or configure the serving cell group to the terminal using signaling (e.g., higher layer signaling). The terminal can confirm the serving cell group indicated by the base station.

[0466] Method 10-6: Information of the same field (e.g., the same DWS field) included in the DCI format may be applied to serving cell(s) belonging to the same TRP in Method 10-5.

[0467] 11. Power Headroom (PH) Reporting Method Considering STxMP

[0468] A UE can transmit two or more SRSs. SRSs can be widely used to compensate for general fast fading in the uplink. SRS configuration (e.g., SRS-Config) can be illustrated in Figures 21 to 23.

[0469] FIG. 21 is a conceptual diagram illustrating a first embodiment of SRS configuration based on the Rel-15 NR technical standard.

[0470] Referring to FIG. 21, in a communication system supporting the Rel-15 NR technical standard, an RRC parameter (e.g., SRS-Config) can indicate multiple SRS resource sets. The SRS resource set can include a variable called usage. The usage included in the SRS resource set can indicate a "resource set related to PUSCH transmission (e.g., an SRS resource set)" and / or a "separate SRS resource set for UL beam management or antenna switching."

[0471] A resource set (e.g., an SRS resource set) for one PUSCH transmission among codebook-based PUSCH transmission and non-codebook-based PUSCH transmission may be indicated by an SRS configuration. The number of SRS resource sets may be 1. The number of SRS resource sets indicated for antenna switching or beam management may be 1 or more.

[0472] FIG. 22 is a conceptual diagram illustrating a first embodiment of SRS configuration based on the Rel-16 NR technical standard.

[0473] 22, in a communication system supporting the Rel-16 NR technical standard, a separate SRS resource set may be indicated for side use, and all functions according to the Rel-15 NR technical standard may be supported. The number of SRS PosResource sets indicated to a terminal may be one or more.

[0474] FIG. 23 is a conceptual diagram illustrating a first embodiment of SRS configuration based on the Rel-17 NR technical standard.

[0475] Referring to FIG. 23, in a communication system supporting the Rel-17 NR technical standard, the number of SRS resource sets utilized for PUSCH transmission may be one or two. To support an sDCI-based mTRP scenario, PUSCH transmission for two TRPs may correspond to respective SRS resource sets on different links. For this configuration, the method of using one SRS resource set in a communication system supporting the Rel-15 / 16 NR technical standard may be extended, where one SRS resource set may correspond to each TRP, and power control, TPMI, SRI, and / or TCI (e.g., joint / UL TCI or TCI) may be controlled separately.

[0476] The base station may indicate a second SRS resource set to the terminal. The terminal may check the second SRS resource set indicated by the base station. The second SRS resource set may be used in an sDCI-based mTRP scenario and / or an mDCI-based mTRP scenario.

[0477] In a communication system supporting the Rel-15 / 16 / 17 NR technical standards, a base station can indicate one SRS resource set associated with PUSCH transmission to a terminal. The terminal can confirm one SRS resource set indicated by the base station. In codebook-based PUSCH transmission, an SRS resource set can include one or two SRS resources. An SRS resource can have four or fewer antenna ports. In non-codebook-based PUSCH transmission, an SRS resource set can include one, two, three, or four SRS resources. An SRS resource can have one antenna port. The number of antenna ports an SRS resource has can be scheduled in direct or indirect association with a PUSCH DM-RS port. Because the maximum number of PUSCH DM-RS ports is four and the number of TBs is one, the number of antenna ports an SRS resource has can be limited.

[0478] In a communication system supporting the Rel-18 NR technical standard, the maximum number of PUSCH DM-RS ports may be 8, and the maximum number of TBs may be 2. In codebook-based PUSCH transmission, an SRS resource set may include two or fewer SRS resources. An SRS resource may have eight or fewer antenna ports. In non-codebook-based PUSCH transmission, an SRS resource set may include 1, 2, 3, 4, 5, 6, 7, or 8 SRS resources. An SRS resource may have one antenna port. The number of antenna ports an SRS resource has may be scheduled to be directly or indirectly associated with the PUSCH DM-RS port.

[0479] An SRS (e.g., an SRS resource, an SRS transmission) may be dropped. Dropping an SRS may mean that the SRS is not transmitted. Dropping an SRS resource may mean that the SRS is not transmitted on the SRS resource. An SRS resource may be dropped according to the priority of the UL signal / channel and the SRS resource. In this case, the SRS may be transmitted on the SRS resource that is not dropped. When an SRS resource is dropped, all SRS symbols belonging to the SRS resource may be dropped. An SRS symbol may mean a symbol on which SRS transmission is performed. In other words, SRS transmission may not be performed on all SRS symbols belonging to the dropped SRS resource. Alternatively, if some SRS symbol(s) belonging to the SRS resource overlap with the UL signal / channel, the SRS may be transmitted on the remaining SRS symbol(s).

[0480] If PUCCH transmission and SRS transmission are performed on the same carrier and semi-persistent or periodic SRS transmission is to be performed in the same symbol as PUCCH transmission with a specific condition, the SRS transmission may not be performed. The PUCCH transmission may include a CSI report, an L1-RSRP report, or an L1-SINR report. If the PUCCH transmission includes a HARQ-ACK, a link recovery request, and / or an SR (scheduling request), the semi-persistent SRS transmission, periodic SRS transmission, or triggered SRS transmission may not be performed in the same symbol as the PUCCH transmission.

[0481] When SRS is not transmitted, only SRS symbols that overlap with PUCCH symbols for which PUCCH transmission is performed (e.g., only SRS transmission in SRS symbols) may be dropped. When aperiodic SRS transmission is performed, PUCCH may not be transmitted. In this case, the PUCCH may include a semi-static CSI report, a static CSI report, a semi-static L1-RSRP report, a static L1-RSRP report, a semi-static L1-SINR report, and / or a static L1-SINR report.

[0482] The SRS may be transmitted simultaneously with other UL signals / channels.

[0483] Interband contiguous CA, interband non-contiguous CA band combination, or intraband non-contiguous CA band combination may be considered. The UE may not support simultaneous transmission of SRS and PUCCH / PUSCH. In this case, the UE may not be instructed to transmit PUSCH / UL DM-RS / UL PT-RS / PUCCH and SRS on different carriers and / or the same symbols.

[0484] Intraband contiguous CA or interband CA band combination may be considered. The UE may not support simultaneous transmission of SRS and PRACH. Alternatively, intraband non-contiguous CA band combination may be considered if a specific RRC parameter (e.g., intraBandNC-PRACH-simulTx-r17) is not instructed to the UE. In this case, the UE may not be instructed to simultaneously transmit SRS and PRACH on different carriers.

[0485] Intraband continuous CA or interband CA band combinations may be considered. The UE may not support simultaneous transmission of SRS and MsgA. In this case, the UE may not be instructed to simultaneously transmit SRS and MsgA on different carriers.

[0486] A terminal can transmit an SRS using one SRS resource. In certain cases, a terminal can simultaneously transmit an SRS using two or more SRS resources. A terminal can transmit an SRS using an SRS resource (e.g., a BM-SRS resource) that belongs to an SRS resource set for beam management. An SRS can be transmitted using overlapping symbol(s) between SRS resources. SRS resources can overlap in some symbol(s).

[0487] SRS can be simultaneously transmitted over the BM-SRS resource. In this case, if the SRS transmission power does not exceed the maximum transmission power that the UE can support, the SRS transmission power (e.g., the transmission power for the BM-SRS resource) can be determined based on technical specifications. The UE can derive path loss using the PL (path loss) RS associated with the BM-SRS resource and perform open-loop power control by compensating for a portion of the path loss, or can perform open-loop power control based on the accumulation of TPC command(s) obtained from DCI(s). If the UE's transmission power is equal to or greater than the maximum transmission power supported by the serving cell or BWP, the UE can transmit the BM-SRS using the maximum transmission power.

[0488] BM-SRS resources i When SRSs are simultaneously transmitted on (i=1, 2), the sum of the magnitudes of the transmit powers (Pi, i=1, 2) required for simultaneous SRS transmission may be greater than the maximum transmit power. When SRSs are simultaneously transmitted on the SRS resource set as well as the BM-SRS resource, the power (e.g., transmit power) of the SRSs may be allocated based on the following method(s).

[0489] In the proposed method, a terminal can select one SRS resource (e.g., SRS resource 1), allocate sufficient power (P1) to the one SRS resource, and allocate remaining power (P2) to the remaining SRS resource (e.g., SRS resource 2). The remaining power can be "the terminal's maximum power (e.g., maximum transmit power) - P1." Alternatively, the remaining power can be less than "the terminal's maximum power (e.g., maximum transmit power) - P1." The method can be applied to SRS transmission (e.g., SRS resources) that utilize one Tx panel.

[0490] Method 11-1: For simultaneous transmission of SRS, one SRS resource set may be selected, and the SRS resources belonging to the selected SRS resource set may be associated with full power, and the other SRS resources may be associated with reduced power.

[0491] The selected SRS resource set may be indicated to the terminal by at least one of RRC signaling or scheduling DCI. For example, the selected SRS resource set may be indicated by a combination of RRC signaling and scheduling DCI. Alternatively, the SRS resource set may be selected based on a technical standard. For example, the first indicated SRS resource set may be selected. Alternatively, the SRS resource set with the smallest SRS resource set ID may be selected. The terminal may consider power allocation for the SRS resource set (e.g., the selected SRS resource set).

[0492] In the proposed method, a terminal can transmit SRS using two or more Tx panels. The SRS can be received by one TRP or two or more TRPs. If the SRS is received by two or more TRPs, one SRS resource can be selected from each of two or more SRS resource sets, and the SRS can be transmitted to each TRP using each selected SRS resource.

[0493] For convenience of explanation, the two SRS resource sets may be referred to as "SRS resource set (or first SRS resource set) and second SRS resource set."

[0494] Method 11-2: To support the mTRP scenario, the second SRS resource set may be additionally instructed to the terminal through base station signaling.

[0495] The SRS resource set for supporting mTRP may be different from the SRS resource set for supporting a single TRP. In this case, the SRS resource set for supporting a single TRP may be referred to separately as the first SRS resource set and the second SRS resource set for supporting mTRP. The SRS resource set and the first SRS resource set may be indicated separately to the terminal.

[0496] Method 11-3: To support the mTRP scenario, the SRS resource set and the first SRS resource set may be separated, and the SRS resource set and the first SRS resource set may be indicated to the terminal through signaling from the base station.

[0497] An SRS resource set for supporting mTRP may be referred to as an SRS resource set pair. The SRS resource set pair may include a first SRS resource set and a second SRS resource set, or the SRS resource set pair may include an SRS resource set and a second SRS resource set.

[0498] Method 11-4: To support the mTRP scenario, the SRS resource set pair can be indicated to the terminal through base station signaling.

[0499] The SRS resource set or the second SRS resource set can include two or more SRS resources. In codebook-based PUSCH transmission, one SRS resource can be interpreted as corresponding to each Tx panel of the terminal. In non-codebook-based PUSCH transmission, one SRS resource can be interpreted as corresponding to each DM-RS port.

[0500] A common power control parameter set for SRS resources belonging to the same SRS resource set may be indicated to the terminal. A common resource type (e.g., semi-static resource, periodic resource, and / or aperiodic resource) for SRS resources belonging to the same SRS resource set may be indicated to the terminal. When the terminal performs STxMP PUSCH transmission, it is preferable that a power control parameter set separated for each Tx panel of the terminal be indicated to the terminal. Therefore, an SRS resource set may be indicated for each Tx panel of the terminal.

[0501] To support this operation, even when an UL signal / channel is received in one TRP, two or more SRS resource sets may be indicated to the UE. Two or more SRS resource sets may be used for transmission of overlapping UL signals / channels or SRSs in all symbols.

[0502] For ease of explanation, the SRS resource set corresponding to each Tx panel may be referred to as a (first) additional SRS resource set or a second additional SRS resource set. The methods or extensions of the methods for the first SRS resource set and the first additional SRS resource set may be applied to the second SRS resource set and the second additional SRS resource set.

[0503] FIG. 24 is a conceptual diagram illustrating a first embodiment of SRS setting taking into account multiple Tx panels, and FIG. 25 is a conceptual diagram illustrating a first embodiment of SRS setting taking into account multiple TRPs and multiple Tx panels.

[0504] 24 and / or 25, two SRS resource sets may be associated with PUSCH transmission. A base station may instruct a terminal to perform codebook-based PUSCH transmission or non-codebook-based PUSCH transmission, and may instruct the terminal to use one or two SRS resource sets.

[0505] Considering an UL signal / channel transmitted to one TRP, an SRS resource set and an additional SRS resource set may be indicated to the terminal. Alternatively, a first SRS resource set and a first additional SRS resource set may be indicated to the terminal. The SRS resource set and the additional SRS resource set may include the same number of SRS resources or different numbers of SRS resources.

[0506] Considering codebook-based PUSCH transmission, the SRS resource set and the supplemental SRS resource set can include the same number of SRS resources. For example, if Tx panels have the same structure, the array configurations used by Tx panels with the same structure may be the same. In other words, the base station can instruct the UE to use the same array configuration for the Tx panel through signaling. For example, if a Tx panel can support up to four ports, the array configuration may be a two-dimensional array expressed as (N1, N2) = (2, 1). Alternatively, if a Tx panel can support up to two ports, the array configuration may be a one-dimensional array expressed as (N1, N2) = (1, 1). N1 may be the maximum number of ports supported in the first dimension of the array. N2 may be the maximum number of ports supported in the second dimension of the array. In this disclosure, port may refer to an antenna port.

[0507] Considering non-codebook-based PUSCH, the SRS resource set and the supplemental SRS resource set can include the same number of SRS resources. For example, if Tx panels have the same structure, Tx panels with the same structure can support the same number of antenna ports. A Tx panel can support up to two or up to four antenna ports.

[0508] Method 11-5: The SRS resource set and the additional SRS resource set can always contain the same number of SRS resources.

[0509] Even if the Tx panels have the same structure, the base station can dynamically instruct the terminal to transmit STxMP or a single Tx panel. The base station can instruct the terminal to transmit up to n layers, and PUSCH transmission can be scheduled by UL DCI and / or RRC signaling. n can be 4 or 8.

[0510] In this situation, the terminal may receive scheduling information (e.g., resource allocation information) for STxMP SDM PUSCH transmission from the base station. In this case, n1 layers may correspond to the SRS resource set, and n2 layers may correspond to the additional SRS resource set. n1 may be less than or equal to maxLayer1, n2 may be less than or equal to maxLayer2, and the sum of n1 and n2 may be n. The combination of (n1, n2) may belong to the combinations allowed by the technical standard. The SRS resource set may include at least one SRS resource, and the number of antenna ports for the SRS resource set (e.g., SRS resource) may be greater than or equal to n1. The additional SRS resource set may include at least one SRS resource, and the number of antenna ports for the additional SRS resource set (e.g., SRS resource) may be greater than or equal to n2. If the Tx panel structure is the same, the maximum value of n1 and the maximum value of n2 may be the same.

[0511] The UE may receive scheduling information (e.g., resource allocation information) for PUSCH transmission using a single Tx panel from the base station. In this case, n layers may correspond to an SRS resource set, and additional SRS resource sets may not correspond to layers. n may be less than maxLayer. n1 may be equal to n. The SRS resource set may include at least one SRS resource, and the number of antenna ports may be greater than or equal to n.

[0512] An SRS resource set can include at least two SRS resources. An additional SRS resource set can include at least one SRS resource. Therefore, the number of SRS resources included in the SRS resource set can be different from the number of SRS resources included in the additional SRS resource set. For example, the number of SRS resources included in the SRS resource set can be greater than the number of SRS resources included in the additional SRS resource set.

[0513] Method 11-6: The number of SRS resources included in the SRS resource set may be different from the number of SRS resources included in the additional SRS resource set.

[0514] The Tx panels may have different structures. If the connection states of the power amplifiers for each Tx panel are different, the Tx panels may have different structures. In this case, the number of antenna ports for the SRS resources belonging to the SRS resource set may be different from the number of antenna ports for the SRS resources belonging to the additional SRS resource set. When n1 and n2 are the numbers of layers corresponding to each Tx panel, n1 ≥ n2 can always be satisfied by the combination of (n1, n2).

[0515] Method 11-7: The number of antenna ports for the SRS resources belonging to the SRS resource set may be different from the number of antenna ports for the SRS resources belonging to the additional SRS resource set.

[0516] Two or more SRS resource sets may be utilized in STxMP PUSCH transmission. Different power control parameter sets may be applied to SRS sets selected from the two or more SRS resource sets. For ease of explanation, the power corresponding to SRS resource 1 belonging to the SRS resource set may be referred to as P1, and the power corresponding to SRS resource 2 belonging to the additional SRS resource set may be referred to as P2. The UE may transmit the PUSCH using a power of P1+P2.

[0517] The terminal can derive P1 and P2 based on the method defined in the technical standard. P1+P2 is the maximum power (e.g., P CMAX、f、c ), the UE can transmit the PUSCH using the power of P1+P2. CMAX、f、c ), the power (eg, transmit power) of the PUSCH may be reduced.

[0518] In the proposed method, a common ratio of power reduction can be assigned to the SRS resource set. The power for each SRS resource can be reduced from Pi to Pi'. The same reduction ratio (e.g., P1' / P1 = P2' / P2 < 1) can be applied to each SRS resource. The terminal's transmit power can be P1' + P2', where P1' + P2' may not be greater than the maximum power.

[0519] Method 11-8: The power allocated to each SRS resource may be reduced by the same ratio. The terminals can simultaneously perform SRS transmissions on the SRS resources using the power reduced by the same ratio. The sum of the transmit powers for the SRS transmissions may not be greater than the maximum power.

[0520] The terminal can utilize Tx panels as follows: For example, the terminal may not use an SRS resource set and may add spatial information of SRS resources belonging to the same SRS resource set. In this case, each Tx panel may be associated with each piece of spatial information.

[0521] For example, the joint / UL TCI or spatial relation information for the SRS resources may be associated with two or more RSs. For example, the CSI-RS, SSB, and / or SRS may be associated with the joint / UL TCI or spatial relation information. The first information may be associated with a first Tx panel, and the second information may be associated with a second Tx panel.

[0522] Method 11-9: Two or more pieces of spatial information allocated to one SRS resource can be indicated or configured, and each piece of spatial information can be associated with a respective Tx panel.

[0523] The operations of the methods according to the embodiments of the present disclosure may be embodied as a computer-readable program or code stored in a computer-readable recording medium. The computer-readable recording medium may include any type of storage device that stores information that can be read by a computer system. The computer-readable recording medium may also be distributed across computer systems connected to a network, so that the computer-readable program or code may be stored and executed in a distributed manner.

[0524] Additionally, the computer-readable recording medium may include a hardware device specially configured to store and execute program instructions, such as a ROM, RAM, flash memory, etc. The program instructions may include not only machine language code, such as that produced by a compiler, but also high-level language code that can be executed by a computer using an interpreter, etc.

[0525] Although some aspects of the present disclosure have been described in the context of an apparatus, they may also be described in terms of a corresponding method, where a block or apparatus corresponds to a method step or feature of a method step. Similarly, aspects described in the context of a method may also be described in terms of a corresponding block or item or feature of a corresponding apparatus. 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 electronic circuitry. In some embodiments, at least one or more of the most significant method steps may be performed by such a device.

[0526] In some embodiments, 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 herein. In some embodiments, a field programmable gate array may operate in conjunction with a microprocessor to perform one of the methods described herein. In general, it is preferred that the methods be performed by some hardware device.

[0527] Although the present disclosure has been described above with reference to preferred embodiments, it will be understood by those skilled in the art that various modifications and variations of the present disclosure may be made without departing from the spirit and scope of the present disclosure as set forth in the following claims.

Claims

1. 1. A method of a terminal, comprising: receiving a first synchronization signal block (SSB) from a first transmission and reception point (TRP); determining a first DL (downlink) timing based on the first SSB; receiving a second SSB from a second TRP; determining a second DL timing based on the second SSB; receiving a physical downlink control channel (PDCCH) order from the first TRP; and A method for a terminal, comprising: when a first information element included in the PDCCH order indicates the second SSB or the second TRP, transmitting an RA (random access) preamble to the second TRP based on the second DL timing.

2. The method of the terminal comprises: The method of claim 1, further comprising transmitting information indicating that the terminal supports two DL timings to at least one of the first TRP or the second TRP.

3. The method of claim 1, wherein the first DL timing is different from the second DL timing, and a difference between the first DL timing and the second DL timing is less than or equal to a cyclic prefix (CP) or exceeds the CP.

4. The method of claim 1, wherein a first timing advance (TA) between the terminal and the first TRP is determined based on the first DL timing, and a second TA between the terminal and the second TRP is determined based on the second DL timing.

5. The method of claim 1, wherein the first information element is information for selecting an SSB index indicating the second SSB or a PCI (physical cell identifier) ​​indicating the second TRP.

6. The method of the terminal comprises: receiving a medium access control (MAC) control element (CE) from the second TRP in response to the RA preamble; and The method further includes deriving at least one of a first TA between the terminal and the first TRP, a second TA between the terminal and the second TRP, or a TAC (TA command) based on the information element included in the MAC CE, The method of claim 1 , wherein the first TA and the second TA belong to different TA groups (TAGs).

7. 7. The method of claim 6, wherein when uplink transmission to which the first TA or the second TA is applied is performed, a TAG identifier referenced to determine the first TA or the second TA is derived from spatial relationship information or transmission configuration indication (TCI) referenced by the uplink transmission.

8. 2. The method of claim 1, wherein the terminal has two or more panels, a first communication between the terminal and the first TRP is performed on a first panel of the two or more panels, and a second communication between the terminal and the second TRP is performed on a second panel of the two or more panels.

9. 1. A method of a base station, comprising: transmitting a first synchronization signal block (SSB) through a first transmission and reception point (TRP) associated with the base station; transmitting a second SSB through a second TRP associated with the base station; transmitting a physical downlink control channel (PDCCH) order to the terminal through the first TRP; and A method for a base station, comprising receiving a random access (RA) preamble from the terminal through the second TRP indicated by the PDCCH order.

10. The base station method includes: The method of claim 9, further comprising receiving information indicating that the terminal supports two DL timings from the terminal through at least one of the first TRP or the second TRP.

11. 10. The method of claim 9, wherein a first DL timing is determined by the terminal based on the first SSB, a second DL timing is determined by the terminal based on the second SSB, the first DL timing is different from the second DL timing, and a difference between the first DL timing and the second DL timing is less than or equal to a cyclic prefix (CP) or exceeds the CP.

12. The base station method of claim 11, wherein a first timing advance (TA) between the terminal and the first TRP is determined based on the first DL timing, and a second TA between the terminal and the second TRP is determined based on the second DL timing.

13. The base station method of claim 9, wherein the PDCCH order includes a first information element, and the first information element is information for selecting an SSB index indicating the second SSB or a PCI (physical cell identifier) ​​indicating the second TRP.

14. The base station method includes: The method further includes transmitting a medium access control (MAC) control element (CE) through the second TRP in response to the RA preamble; The information element included in the MAC CE is used to derive at least one of a first TA between the terminal and the first TRP, a second TA between the terminal and the second TRP, or a TAC (TA command), The method of claim 9, wherein the first TA and the second TA belong to different TA groups (TAGs).

15. 15. The method of claim 14, wherein when uplink transmission to which the first TA or the second TA is applied is performed, a TAG identifier referenced to determine the first TA or the second TA is derived from spatial relationship information or transmission configuration indication (TCI) referenced by the uplink transmission.

16. A terminal, at least one processor; The at least one processor is configured to: receiving a first synchronization signal block (SSB) from a first transmission and reception point (TRP); determining a first DL (downlink) timing based on the first SSB; receiving a second SSB from a second TRP; determining a second DL timing based on the second SSB; receiving a physical downlink control channel (PDCCH) order from the first TRP; and If the first information element included in the PDCCH order indicates the second SSB or the second TRP, the terminal causes the RA (random access) preamble to be transmitted to the second TRP based on the second DL timing.

17. The at least one processor is configured to: The terminal of claim 16, further causing the terminal to transmit information indicating that the terminal supports two DL timings to at least one of the first TRP or the second TRP.

18. The terminal of claim 16, wherein the first DL timing is different from the second DL timing, and a difference between the first DL timing and the second DL timing is less than or equal to a cyclic prefix (CP) or exceeds the CP.

19. The terminal of claim 16, wherein the first information element is information for selecting an SSB index indicating the second SSB or a physical cell identifier (PCI) indicating the second TRP.

20. The at least one processor is configured to: receiving a medium access control (MAC) control element (CE) from the second TRP in response to the RA preamble; and Further, based on the information element included in the MAC CE, at least one of a first TA between the terminal and the first TRP, a second TA between the terminal and the second TRP, or a TAC (TA command) is derived; The terminal of claim 16, wherein the first TA and the second TA belong to different TA groups (TAGs).

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