Method and apparatus for transmitting signals in asymmetric multiple transmission / reception point scenario

Abstract

A method performed by a UE according to embodiments of the present disclosure can comprise the steps of: receiving, in an RRC connected state with a first TRP, a first message from the first TRP, the first message indicating to transmit a first UL signal to the first TRP or a second TRP; generating the first UL signal based on the received first message; and transmitting the generated first UL signal to the second TRP when the received first message indicates to the second TRP, wherein the second TRP can be controlled by the first TRP.

Description

Technical Field

[0001] This disclosure relates to signal transmission technology, and more specifically, to signal transmission technology in asymmetric multiple transmitter and receiver (m-TRP) scenarios. Background Technology

[0002] With the development of information and communication technologies, various wireless communication technologies have been developed. Typical wireless communication technologies include Long Term Evolution (LTE) and New Radio (NR) as defined in the 3rd Generation Partnership Project (3GPP) standards. LTE can be one of the fourth-generation (4G) wireless communication technologies, and NR can be one of the fifth-generation (5G) wireless communication technologies.

[0003] To handle the rapidly growing wireless data following the commercialization of fourth-generation (4G) communication systems (e.g., Long Term Evolution (LTE) or LTE-A Advanced), fifth-generation (5G) communication systems (e.g., New Radio (NR) systems) are being considered, utilizing frequency bands higher than those of 4G (e.g., 6 GHz or above) and those of 4G (e.g., below 6 GHz). 5G communication systems can support enhanced mobile broadband (eMBB), ultra-reliable and low-latency communication (URLLC), and massive machine-type communication (mMTC).

[0004] In wireless communication systems, the communication method using Transmitting and Receiving Points (TRPs) has been used to extend the coverage of base stations. In this scenario, a User Equipment (UE) can communicate with multiple TRPs (mTRPs). In other words, the UE can send signals to and / or receive signals from mTRPs via downlink (DL) and / or uplink (UL). Each of the multiple TRPs can be installed in a different geographical location and can have different coverage areas. In asymmetric mTRP scenarios where multiple TRPs have different coverage areas, the UE may need a method of communicating with one or more TRPs. Summary of the Invention

[0005] [Technical Issues]

[0006] This disclosure aims to provide procedures, methods, and apparatus for enabling a terminal to communicate with one or more TRPs in an asymmetric mTRP scenario.

[0007] [Technical Solution]

[0008] According to an exemplary embodiment of the present disclosure, a method for a user equipment (UE) to achieve the above-described objectives may include: receiving a first message from a first TRP while in a radio resource control (RRC) connection state with a first transmitting and receiving point (TRP), the first message instructing the transmission of a first uplink (UL) signal to the first TRP or to a second TRP; generating a first UL signal based on the received first message; and transmitting the generated first UL signal to the second TRP based on the instruction of the first message, wherein the second TRP is a TRP controlled by the first TRP.

[0009] The first UL signal can be a random access (RA) preamble transmitted via the Physical Random Access Channel (PRACH).

[0010] The first message may be downlink control information (DCI) for physical downlink control channel (PDCCH) commands, and the DCI may include a first field indicating whether path loss (PL) offset is used when determining the transmit power of the first UL signal, and indicating information related to the PL offset.

[0011] The first field may be present when the first parameter included in the RRC message received from the first TRP indicates activation of the first field, and the RRC message is configured with one or more indicated Transport Configuration Indication (TCI) states corresponding to the PL offset.

[0012] When the first parameter of an RRC message received from the first TRP prior to receiving the first message indicates activation of the first field included in the DCI, and the TCI configured in the RRC message or in a Media Access Control-Control Element (MAC-CE) message received from the first TRP prior to receiving the first message indicates a combined / UL TCI state corresponding to the PL offset, the first field may indicate whether the PL offset corresponding to the combined / UL TCI state is used when determining the transmit power of the first UL signal sent to the second TRP.

[0013] The method may further include: receiving an RRC message or a MAC-CE message from a first TRP before receiving the first message, wherein when the TCI configured within the RRC message or MAC-CE message indicates two combined / UL TCI states corresponding to the PL offset, the first field may indicate the use of a PL offset corresponding to one of the indicated combined / UL TCI states when determining the transmission power of a second UL signal sent to a second TRP.

[0014] When the first parameter of the RRC message received from the first TRP prior to the receipt of the first message indicates the activation of the first field included in the DCI, and the RRC message configures two indicated joint / UL TCI states along with the PL offset for the serving cell, the first field may indicate the use of one of the two joint / UL TCI states to transmit the first UL signal.

[0015] When the first field indicates that the PL offset is applied to the TCI state or UL TCI state indicated by the higher layer, the first PL offset applied to determine the transmit power of the first UL signal may be based on the difference between the path loss (PL) associated with the transmission of the first UL signal in the active downlink (DL) bandwidth portion (BWP) from the first TRP and the PL offset.

[0016] According to an exemplary embodiment of the present disclosure, a method for establishing a first transmitting and receiving point (TRP) to achieve the above objectives may include: sending a first message to a user equipment (UE) in a radio resource control (RRC) connection state, the first message instructing the transmission of a first uplink (UL) signal to one or more second TRPs; receiving first information related to the first message from one or more second TRPs; and sending a second message based on the first information, the second message instructing the transmission of a second UL signal to one or more second TRPs, wherein the one or more second TRPs are TRPs controlled by the first TRP.

[0017] The first UL signal can be a random access (RA) preamble transmitted via the Physical Random Access Channel (PRACH).

[0018] The first message may be downlink control information (DCI) for physical downlink control channel (PDCCH) commands, and the DCI may include a first field indicating whether path loss (PL) offset is used when determining the transmit power of the first UL signal, and indicating information related to the PL offset.

[0019] The method may further include: sending an RRC message to the UE before sending the first message, wherein the first field may be included in the DCI when a first parameter included in the RRC message indicates activation of the first field and one or more indicated Transmission Configuration Indication (TCI) states corresponding to the PL offset are configured in the RRC message.

[0020] The method may further include: sending an RRC message or a Media Access Control-Control Element (MAC-CE) message to the UE before sending the first message, wherein when the TCI configured in the RRC message or MAC-CE message indicates two joint / UL TCI states corresponding to the PL offset, the first field may indicate the use of the PL offset corresponding to one of the indicated joint / UL TCI states when determining the transmission power of the second UL signal sent to the second TRP.

[0021] The method may further include: sending an RRC message and a MAC-CE message to the UE before sending the first message, wherein when the first parameter of the RRC message indicates activation of the first field included in the DCI, and the TCI configured in the RRC message or MAC-CE message received before receiving the first message indicates a combined / UL TCI state corresponding to the PL offset, the first field may indicate whether the PL offset corresponding to the combined / UL TCI state is used when determining the transmission power of the first UL signal sent to the second TRP.

[0022] The method may further include: sending an RRC message to the UE before sending the first message, wherein when the first parameter of the RRC message indicates activation of the first field included in the DCI, and the RRC message configures two indicated joint / UL TCI states along with the PL offset for the serving cell, the first field may indicate the use of one of the two joint / UL TCI states to send the first UL signal.

[0023] When the first field indicates that the PL offset is applied to the TCI state or UL TCI state indicated by the higher layer, the first PL offset applied to determine the transmit power of the first UL signal may be based on the difference between the path loss (PL) associated with the transmission of the first UL signal in the active downlink (DL) bandwidth portion (BWP) from the first TRP and the PL offset.

[0024] According to an exemplary embodiment of the present disclosure for achieving the above objectives, a user equipment (UE) may include: at least one processor, wherein the at least one processor may cause the UE to perform: receiving a first message from a first TRP while in a radio resource control (RRC) connection state with a first transmitting and receiving point (TRP), the first message instructing the transmission of a first uplink (UL) signal to the first TRP or to a second TRP; generating a first UL signal based on the received first message; and transmitting the generated first UL signal to the second TRP based on the instruction of the first message, wherein the second TRP is a TRP controlled by the first TRP.

[0025] The first UL signal can be a random access (RA) preamble transmitted via the Physical Random Access Channel (PRACH).

[0026] The first message may be downlink control information (DCI) for physical downlink control channel (PDCCH) commands, and the DCI may include a first field indicating whether path loss (PL) offset is used when determining the transmit power of the first UL signal, and indicating information related to the PL offset.

[0027] The first field may be present when the first parameter included in the RRC message received from the first TRP indicates activation of the first field, and the RRC message is configured with one or more indicated Transport Configuration Indication (TCI) states corresponding to the PL offset.

[0028] [Beneficial Effects]

[0029] According to exemplary embodiments of this disclosure, a transmission and reception process that maximizes uplink capacity in an asymmetric mTRP deployment scenario can be provided. Specifically, in an asymmetric mTRP deployment scenario, the uplink transmission power and uplink transmission beam direction toward the uplink-only TRP can be determined by considering the UE's mobility. Furthermore, according to exemplary embodiments of this disclosure, the first TRP can indicate an appropriate uplink transmission power to the UE, thereby mitigating inter-cell interference problems caused by excessive uplink transmission power toward the uplink-only TRP. Additionally, the uplink asynchrony problem of previously unknown uplink-only TRPs can be resolved. Therefore, in an asymmetric mTRP deployment scenario, the UE can transmit uplink signals (or data) to the uplink-only TRP with appropriate power, thereby achieving faster data transmission and reducing UE power consumption. Attached Figure Description

[0030] Figure 1 This is a conceptual diagram illustrating an exemplary embodiment of a communication system.

[0031] Figure 2 This is a block diagram illustrating an exemplary embodiment of a communication node constituting a communication system.

[0032] Figure 3a This is a conceptual diagram illustrating signal transmission between multiple TRPs and UEs within a cell.

[0033] Figure 3b This is a conceptual diagram illustrating signal transmission between multiple TRPs and UEs in a cell.

[0034] Figure 4 This is a conceptual diagram illustrating signal transmission between the TRP and the UE in an asymmetric mTRP scenario.

[0035] Figure 5 This is a conceptual diagram illustrating the first scenario in an asymmetric mTRP environment.

[0036] Figure 6 This is a conceptual diagram illustrating the second scenario in an asymmetric mTRP environment.

[0037] Figure 7a This is a conceptual diagram illustrating a third scenario in an asymmetric mTRP environment.

[0038] Figure 7b This is a timing diagram showing the transmission and reception timing of signals between the UE and the TRP in the third scenario of an asymmetric mTRP environment.

[0039] Figure 8a This is a conceptual diagram of the first sub-scene of the third scenario, illustrating an asymmetric mTRP environment.

[0040] Figure 8b This is a timing diagram showing the transmission and reception timing of signals between the UE and TRP at the initial position of acquiring synchronization in the first sub-scenario of the third scenario of the asymmetric mTRP environment.

[0041] Figure 8c This is a timing diagram showing the transmission and reception timing of signals between the UE and the TRP in the first sub-scenario of the third scenario of an asymmetric mTRP environment, when the UE moves from the initial position of acquiring synchronization.

[0042] Figure 9 This is a timing diagram illustrating the case where an OOS problem occurs only at UL TRP and the minimum absolute value of the asynchronous operation.

[0043] Figure 10a This is a sequence diagram illustrating the initial access procedure of the UE in the third scenario of an asymmetric mTRP environment.

[0044] Figure 10b This is a sequence diagram illustrating the uplink transmission of the UE in the third scenario of an asymmetric mTRP environment.

[0045] Figure 11 This is a conceptual diagram illustrating the completion of RRC configuration between the UE and the first TRP in a third scenario of an asymmetric mTRP environment.

[0046] Figure 12 This is a conceptual diagram illustrating the situation where the UE transmits uplink signals via beam scanning in the third scenario of an asymmetric mTRP environment.

[0047] Figure 13 This is a conceptual diagram illustrating the case where only the UL TRP sends an estimate to the first TRP in an asymmetric mTRP environment.

[0048] Figure 14 This is a conceptual diagram illustrating the scenario in an asymmetric mTRP environment where the macro TRP sends mapping information to the UE based on estimates received from the UL TRP only.

[0049] Figure 15 This is a conceptual diagram illustrating an example of the relationship between the PL offset configuration, delta PL configuration, and TCI state configuration required for uplink power control.

[0050] Figure 16 This is a conceptual diagram illustrating the first PL offset MAC-CE configuration according to the seventh exemplary embodiment.

[0051] Figure 17 This is a conceptual diagram illustrating the second PL offset MAC-CE configuration according to the seventh exemplary embodiment.

[0052] Figure 18 This is a conceptual diagram illustrating the third PL offset MAC-CE configuration according to the seventh exemplary embodiment.

[0053] Figure 19 This is a conceptual diagram illustrating the fourth PL offset MAC-CE configuration according to the seventh exemplary embodiment.

[0054] Figure 20 This is a conceptual diagram illustrating uplink communication between the UE and a UL-only TRP in an asymmetric mTRP environment. Detailed Implementation

[0055] While this disclosure can have various modifications and alternatives, specific embodiments thereof are shown by way of example in the accompanying drawings and will be described in detail herein. However, it should be understood that this disclosure is not intended to be limited to the specific forms disclosed, but rather, this disclosure will cover all modifications, equivalents, and alternatives falling within the spirit and scope of this disclosure. Throughout the description of the accompanying drawings, the same numerals refer to the same elements.

[0056] It should be understood that although the terms first, second, etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used only to distinguish one element from another. For example, without departing from the scope of this disclosure, a first element may be referred to as a second element, and similarly, a second element may be referred to as a first element. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0057] In exemplary embodiments of this disclosure, "at least one of A and B" may refer to "at least one of A or B" or "at least one of one or more combinations of A and B". Furthermore, "one or more of A and B" may refer to "one or more of A or B" or "one or more of one or more combinations of A and B".

[0058] It should be understood that when an element is described as "connected" or "coupled" to another element, it can be directly connected or coupled to the other element, or there may be intermediate elements. Conversely, when an element is described as "directly connected" or "directly coupled" to another element, there are no intermediate elements. Other terms used to describe the relationship between elements should be interpreted in a similar manner (i.e., "between" versus "directly between," "adjacent" versus "directly adjacent," etc.).

[0059] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit this disclosure. As used herein, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that when the terms “comprising,” “including,” “containing,” and / or “comprising” are used herein, they specify the presence of the stated features, integers, steps, operations, elements, and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and / or groups thereof.

[0060] Unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains. It should also be understood that terms (such as those defined in common dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant field, and should not be interpreted in an idealized or overly formal sense unless explicitly defined herein.

[0061] The following describes a communication system applied according to exemplary embodiments of the present disclosure. The communication system applied according to exemplary embodiments of the present disclosure is not limited to what is described below, and exemplary embodiments of the present disclosure can be applied to various communication systems. Here, "communication system" can have the same meaning as "communication network".

[0062] Throughout this disclosure, for example, networks may include wireless internet (such as WiFi), mobile internet (such as WiBro or WiMax), 2G mobile communication networks (such as GSM or CDMA), 3G mobile communication networks (such as WCDMA or CDMA2000), 3.5G mobile communication networks (such as HSDPA or HSUPA), 4G mobile communication networks (such as LTE or LTE-Advanced networks), 5G mobile communication networks, B5G mobile communication networks (e.g., 6G mobile communication networks), etc.

[0063] Throughout this disclosure, "terminal" may refer to mobile station, mobile terminal, subscriber station, portable subscriber station, user equipment, access terminal, etc., and may include all or part of the functions of terminal, mobile station, mobile terminal, subscriber station, mobile subscriber station, user equipment, access terminal, etc.

[0064] Here, desktop computers, laptops, tablet PCs, cordless phones, mobile phones, smartphones, smartwatches, smart glasses, e-book readers, portable multimedia players (PMPs), portable game consoles, navigation devices, digital cameras, digital multimedia broadcast (DMB) players, digital audio recorders, digital audio players, digital image recorders, digital image players, digital video recorders, and digital video players with communication capabilities can be used as terminals.

[0065] Throughout this specification, "base station" may refer to access point, radio access station, Node B (NB), evolved Node B (eNB), base transceiver station, mobile multi-hop relay (MMR)-BS, etc., and may include all or part of the functions of base station, access point, radio access station, NB, eNB, base transceiver station, MMR-BS, etc.

[0066] Preferred exemplary embodiments of the present disclosure will be described in more detail below with reference to the accompanying drawings. In describing the present disclosure, the same reference numerals are used for the same elements in the drawings for ease of full understanding, and repeated descriptions of the same elements are omitted.

[0067] Figure 1 This is a conceptual diagram illustrating an exemplary embodiment of a communication system.

[0068] refer to Figure 1 The communication system 100 may include multiple 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. These multiple communication nodes can support 4G communication (e.g., Long Term Evolution (LTE), LTE-A Advanced), 5G communication (e.g., New Radio (NR)), 6G communication, etc., as specified in the 3GPP standards. 4G communication can be performed in frequency bands below 6 GHz, and 5G and 6G communication can be performed in frequency bands above 6 GHz and in frequency bands below 6 GHz.

[0069] For example, to execute 4G, 5G, and 6G communications, multiple communication protocols can support those based on Code Division Multiple Access (CDMA), Wideband CDMA (WCDMA), Time Division Multiple Access (TDMA), Frequency Division Multiple Access (FDMA), Orthogonal Frequency Division Multiplexing (OFDM), Filtered OFDM, Cyclic Prefix OFDM (CP-OFDM), Discrete Fourier Transform Spread OFDM (DFT-s-OFDM), Orthogonal Frequency Division Multiple Access (OFDMA), Single Carrier FDMA (SC-FDMA), and Non-Orthogonal Multiple Access (NOMA). Communication protocols include those based on generalized frequency division multiplexing (GFDM), filter bank multi-carrier (FBMC), universal filtered multi-carrier (UFMC), space division multiple access (SDMA), and orthogonal time-frequency space (OTFS).

[0070] In addition, the communication system 100 may also include a core network. When the communication system 100 supports 4G communication, the core network may include a Serving Gateway (S-GW), a Packet Data Network (PDN) Gateway (P-GW), a Mobility Management Entity (MME), etc. When the communication system 100 supports 5G or 6G communication, the core network may include User Plane Function (UPF), Session Management Function (SMF), Access and Mobility Management Function (AMF), etc.

[0071] In addition, each of the 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 constituting the communication system 100 may have the following structure.

[0072] Figure 2 This is a block diagram illustrating an exemplary embodiment of a communication node constituting a communication system.

[0073] refer to Figure 2 The communication node 200 may include at least one processor 210, a memory 220, and a transceiver 230 connected to a network to perform communication. Furthermore, the communication node 200 may also include an input interface device 240, an output interface device 250, a storage device 260, etc. Each component included in the communication node 200 can be connected to each other via a bus 270 to communicate.

[0074] However, each component included in communication node 200 may not be connected to the common bus 270, but may be connected to processor 210 via a separate interface or a separate bus. For example, processor 210 may be connected to at least one of memory 220, transceiver 230, input interface device 240, output interface device 250 and storage device 260 via a dedicated interface.

[0075] Processor 210 can execute a program stored in at least one of memory 220 and storage device 260. Processor 210 may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor that executes methods according to embodiments of the present disclosure thereon. Each of memory 220 and storage device 260 may be constituted by at least one of volatile storage medium and non-volatile storage medium. For example, memory 220 may include at least one of read-only memory (ROM) and random access memory (RAM).

[0076] Refer again Figure 1The 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. Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 may form a macro cell, and each of the fourth base station 120-1 and the fifth base station 120-2 may form a small cell. The fourth base station 120-1, the third terminal 130-3, and the fourth terminal 130-4 may be within the cell coverage area of ​​the first base station 110-1. Furthermore, the second terminal 130-2, the fourth terminal 130-4, and the fifth terminal 130-5 may be within the cell coverage area of ​​the second base station 110-2. Furthermore, the fifth base station 120-2, the fourth terminal 130-4, the fifth terminal 130-5, and the sixth terminal 130-6 can all fall within the cell coverage area of ​​the third base station 110-3. Additionally, the first terminal 130-1 can fall within the cell coverage area of ​​the fourth base station 120-1, and the sixth terminal 130-6 can fall within the cell coverage area of ​​the fifth base station 120-2.

[0077] Here, each of the multiple base stations 110-1, 110-2, 110-3, 120-1, and 120-2 can refer to a Node B (NB), an evolved Node B (eNB), a gNB, a Base Transceiver Station (BTS), a radio base station, a radio transceiver, an access point, an access node, a Roadside Unit (RSU), a Radio Remote Header (RRH), a Transmitting Point (TP), a Transmitting and Receiving Point (TRP), etc.

[0078] Each of the multiple terminals 130-1, 130-2, 130-3, 130-4, 130-5 and 130-6 can refer to a user equipment (UE), terminal, access terminal, mobile terminal, station, subscriber station, mobile station, portable subscriber station, node, device, Internet of Things (IoT) device, installed module / device / terminal, vehicle-mounted device / terminal, etc.

[0079] Furthermore, each of the multiple base stations 110-1, 110-2, 110-3, 120-1, and 120-2 can operate in the same or different frequency bands. The multiple base stations 110-1, 110-2, 110-3, 120-1, and 120-2 can be interconnected via ideal or non-ideal backhaul, and exchange information with each other via ideal or non-ideal backhaul. In addition, each of the multiple base stations 110-1, 110-2, 110-3, 120-1, and 120-2 can be connected to the core network via ideal or non-ideal backhaul. 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 terminal 130-1, 130-2, 130-3, 130-4, 130-5, or 130-6, and transmit signals received from the corresponding terminal 130-1, 130-2, 130-3, 130-4, 130-5, or 130-6 to the core network.

[0080] In addition, each of the multiple base stations 110-1, 110-2, 110-3, 120-1, and 120-2 can support multi-input multi-output (MIMO) transmission (e.g., single-user MIMO, multi-user MIMO, massive MIMO, etc.), coordinated multipoint (CoMP) transmission, carrier aggregation (CA) transmission, transmission in unlicensed frequency bands, device-to-device (D2D) communication (or proximity services (ProSe)), etc. Here, each of the multiple terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6 can perform operations corresponding to the operations of the multiple base stations 110-1, 110-2, 110-3, 120-1, and 120-2, as well as operations supported by the multiple base stations 110-1, 110-2, 110-3, 120-1, and 120-2. For example, the second base station 110-2 can transmit signals to the fourth terminal 130-4 in SU-MIMO mode, and the fourth terminal 130-4 can receive signals from the second base station 110-2 in SU-MIMO mode. Alternatively, the second base station 110-2 can transmit signals to the fourth terminal 130-4 and the fifth terminal 130-5 in MU-MIMO mode, and the fourth terminal 130-4 and the fifth terminal 130-5 can receive signals from the second base station 110-2 in MU-MIMO mode.

[0081] The first base station 110-1, the second base station 110-2, and the third base station 110-3 can transmit signals to the fourth terminal 130-4 in CoMP mode, 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 in CoMP mode. Furthermore, each of the multiple base stations 110-1, 110-2, 110-3, 120-1, and 120-2 can exchange signals with corresponding terminals 130-1, 130-2, 130-3, 130-4, 130-5, or 130-6 within its cell coverage area in CA mode. Each of base stations 110-1, 110-2 and 110-3 can control the D2D communication between the fourth terminal 130-4 and the fifth terminal 130-5, so the fourth terminal 130-4 and the fifth terminal 130-5 can perform D2D communication under the control of the second base station 110-2 and the third base station 110-3.

[0082] The following describes methods for configuring and managing radio interfaces in a communication system. Even when a method (e.g., transmitting or receiving a signal) performed at a first communication node is described, a corresponding second communication node can also perform a method (e.g., receiving or transmitting a signal) corresponding to the method performed at the first communication node. That is, when describing the operation of a terminal, the corresponding base station can perform an operation corresponding to the terminal's operation. Conversely, when describing the operation of a base station, the corresponding terminal can perform an operation corresponding to the base station's operation.

[0083] In addition, in a communication system, a base station can perform all functions of the communication protocol (e.g., remote radio transmission / reception, baseband processing, etc.). Alternatively, the remote radio transmission / reception function, among all functions of the communication protocol, can be performed by a Transmit and Receive Point (TRP) (e.g., a flexible (f)-TRP), and the baseband processing function, among all functions of the communication protocol, can be performed by a Baseband Unit (BBU) block. A TRP can be a Remote Radio Header (RRH), Radio Unit (RU), Transmit Point (TP), etc. A BBU block can include at least one BBU or at least one Digital Unit (DU). A BBU block can be referred to as a 'BBU pool', 'centralized BBU', etc. A TRP can be connected to a BBU block via a wired fronthaul link or a wireless fronthaul link. A communication system consisting of a backhaul link and a fronthaul link can be as follows. When a function splitting scheme of the communication protocol is applied, the TRP can selectively perform some functions of the BBU or some functions of the Media Access Control (MAC) / Radio Link Control (RLC) layer.

[0084] In this disclosure, a node communicating with a base station or transmit and receive point (TRP) is referred to as a user equipment (UE). The TRP may be controlled by a base station (BS). The UE, BS, and / or TRP may include the aforementioned... Figure 2 The UE may include at least a portion of the components shown, and may also include additional components. For example, for user convenience, the UE may also include various interfaces and / or sensors. The BS may also include interfaces (e.g., backhaul interfaces and / or fronthaul interfaces) for communicating with the TRP, another BS, and / or specific network functions (NFs) of the core network. The TRP may also include interfaces for communicating with the BS. However, it should be noted that this is for ease of description, and the present disclosure is not limited thereto. All possible configurations explained by the concepts of the methods, processes, and apparatus according to the present disclosure may be included within the scope of this disclosure.

[0085] Figure 3a This is a conceptual diagram illustrating signal transmission between multiple TRPs and UEs within a cell, and Figure 3b This is a conceptual diagram illustrating signal transmission between multiple TRPs and UEs in a cell.

[0086] Reference Figure 3a and Figure 3b Previously, it should be noted that the UE described below can be understood as a terminal and / or mobile station (MS) as described above. The TRP can belong to the same BS or different BSs.

[0087] refer to Figure 3a This illustrates a scenario where two different TRPs 311 and 312 are included in a single cell 310. As mentioned above, cell 310 can be an area managed by a single BS. Being an area managed by a single BS may mean that the Physical Cell Identity (PCI) is the same within cell 310. In other words, the first TRP 311 and the second TRP 312 can broadcast the same PCI to UE 301 within cell 310. Although... Figure 3a This disclosure only illustrates the case where two TRPs, 311 and 312, exist within a single cell 310; however, it is not limited to this. In other words, it is possible for a single cell 310 to contain only one TRP and for it to contain three or more TRPs. Therefore, Figure 3a An exemplary embodiment of a scenario where multiple TRPs (mTRPs) belong to a single cell is illustrated. The meaning of mTRPs belonging to a single cell can correspond to the case where mTRPs broadcast the same PCI. Therefore, UE 301 can receive the same PCI from each of the two TRPs 311 and 312. As described above, the situation where two or more TRPs exist within a single cell 310 is hereinafter referred to as an 'intra-cell mTRP environment' or 'intra-cell mTRP scenario'.

[0088] refer to Figure 3b This illustrates a scenario where each of two different cells 320 and 330 includes a TRP 321 or TRP 331. As mentioned above, each of cells 320 and 330 can be an area managed by a corresponding BS. In other words, the first cell 320 can be managed by a first BS ( Figure 3b The area managed by (not shown in the image) and the second cell 330 can be managed by the second BS ( Figure 3b (Not shown in the image) manages the area. Therefore, when the PCI of the first cell 320 is referred to as the first PCI, the first BS and the third TRP 321 can broadcast the first PCI, and when the PCI of the second cell 330 is referred to as the second PCI, the second BS and the fourth TRP 331 can broadcast the second PCI. When UE 301 communicates with the first cell 320, the second cell 330 can be a neighboring cell. As another example, when UE 301 communicates with the second cell 330, the first cell 320 can be a neighboring cell. Although Figure 3b The illustration shows a case where a cell contains only one TRP, but this disclosure is not limited thereto. In other words, the same applies to cases where two or more TRPs broadcasting the corresponding cell's PCI exist in a single cell. Therefore, UE 301 can receive the corresponding cell's PCI from one cell and / or two or more cells. As described above, when one or more TRPs exist in each cell, and UE 301 receives a first PCI from a TRP belonging to a serving cell (e.g., the first cell 320) (e.g., the third TRP 321) and a second PCI from a TRP belonging to a non-serving cell (e.g., the second cell 330) (e.g., the fourth TRP 331), this situation is referred to as an "inter-cell environment" or "inter-cell scenario".

[0089] Figure 4 This is a conceptual diagram illustrating signal transmission between the TRP and the UE in an asymmetric mTRP scenario.

[0090] refer to Figure 4 Base station 441 can communicate with UE 411 located in its cell using multiple TRPs 401, 402, and 403. Figure 4 In the example, for the sake of simplicity, three TRPs 401, 402, and 403 are shown. However, the number of TRPs that can be included in base station 441 is not limited to three. In other words, base station 441 can include only one TRP, two TRPs, or four or more TRPs. However, since this disclosure describes an mTRP environment, the case where base station 441 includes only one TRP is not considered.

[0091] exist Figure 4In an exemplary embodiment, it is assumed that a base station 441 includes three different TRPs. The first TRP 401 may have a first cell area 410, the second TRP 402 may have a second cell area 420, and the third TRP 403 may have a third cell area 430. For example... Figure 4 As shown, the first cell region 410 formed by the first TRP 401 can have the widest area, and the first cell region 410 can overlap with the second cell region 420 and the third cell region 430. More specifically, the second cell region 420 formed by the second TRP 402 can be included within the first cell region 410, and the third cell region 430 formed by the third TRP 403 can be included within the first cell region 410.

[0092] Typically, the received signal power is inversely proportional to the square of the transmission distance. When using the same transmit power, under the same propagation conditions, the cell area formed by the signal can be of the same size. Based on this, according to... Figure 4 The configurations of cell areas 410, 420, and 430 shown indicate that, compared to the first TRP 401, the second TRP 402 and the third TRP 403 are low-power TRPs. Figure 4 The example shows a case where a portion of the second cell region 420 overlaps with a portion of the third cell region 430. However, the second cell region 420 and the third cell region 430 may not overlap.

[0093] Additionally, the first TRP 401 can perform downlink (DL) and uplink (UL) communication with the UE 411, and the second TRP 402 and / or the third TRP 403 can also perform DL and UL communication with the UE 411. Figure 4 In the example, UE 411 is shown as being located outside the second cell 420 configured by the second TRP 402; however, this is due to limitations in the accompanying drawings, and in the following description, it is assumed that UE 411 is located within the second cell 420. Furthermore, in Figure 4 In the example, UE 411 is shown as being located outside the third cell 430 configured by the third TRP 403; however, this is due to limitations in the accompanying drawings, and in the following description, it is assumed that UE 411 is located within the third cell 430. Figure 4 The diagram shows that the DL transmission from the second TRP 402 to the UE 411 is a "minimum transmission", and the DL transmission from the third TRP 403 to the UE 411 is also a "minimum transmission". Here, the term "minimum transmission" can refer to the transmission of a small amount of data (or signals), including control information.

[0094] exist Figure 4The diagram shows that the UL transmission from UE 411 to the second TRP 402 is a "maximum transmission," and the UL transmission from UE 411 to the third TRP 403 is also a "maximum transmission." Here, the term "maximum transmission" can refer to the transmission of a large amount of data (or signals), including control information. In other words, "maximum transmission" can refer to the transmission of most data (or signals).

[0095] It should be noted that, Figure 4 In the example, there is no indication of a DL transmission from the first TRP 401 to the UE 411. A DL transmission from the first TRP 401 to the UE 411 (without an indication provided) can indicate a transmission according to the communication specification. In other words, a DL transmission from the first TRP 401 to the UE 411 can indicate that not only all control information but also data can be transmitted via the downlink. Similarly, it should be noted that in Figure 4 In the example, there is no indication of a UL transmission from UE 411 to the first TRP 401. A UL transmission from UE 411 to the first TRP 401 (without an indication of it) could indicate a transmission according to the communication specification. In other words, a UL transmission from UE 411 to the first TRP 401 could indicate that not only all control information but also data can be transmitted via the uplink.

[0096] like Figure 4 As shown, when three different TRPs 401, 402, and 403 are configured within base station 441, DL data transmission to UE 411 can be primarily performed by the first TRP 401. On the other hand, as... Figure 4 As shown, when three different TRPs 401, 402, and 403 are configured within base station 441, UL data transmitted by UE 411 can typically be sent to the second TRP 402 and / or the third TRP 403. This is because UE 411 can reduce transmission power consumption by transmitting data via the one or two TRPs closest to UE 411. Therefore, when applying... Figure 4 When configured, UE 411 can send data to the second TRP 402 and / or the third TRP 403 via UL transmission.

[0097] The scenario in which UL data transmission and DL data reception are performed using different TRPs is referred to as the "asymmetric mTRP scenario" in the following description. On the other hand, the above Figure 3a and Figure 3b The mTRP scenario shown (in which UL transmission and DL reception are performed via the same TRP) can be referred to as a "symmetric mTRP scenario".

[0098] As of the current standard specifications, there is no information on how UE 411 should... Figure 4 The document outlines the procedures for performing initial system access in the asymmetric mTRP scenario shown. Furthermore, as of the current standard specifications, there are no provisions regarding... Figure 4 The illustrated asymmetric mTRP scenario specifies a method for UL synchronization between UE 411 and each of the low-power TRPs 402 and 403. Furthermore, the current standard specification does not define procedures for determining the UL transmit power of UE 411 and for UL data transmission of UE 411 in asymmetric mTRP scenarios. Therefore, methods are needed for performing initial access, UL synchronization, UL power determination, and UL data transmission in asymmetric mTRP scenarios.

[0099] In this disclosure described below, the wireless communication device is referred to as UE, the device receiving signals from the UE is referred to as TRP, and the device managing the TRP is referred to as base station (BS). The upper-layer entity managing the BS is referred to as network (NW) or core NW, and the area managed by the BS is referred to as cell.

[0100] Figure 5 This is a conceptual diagram illustrating the first scenario in an asymmetric mTRP environment.

[0101] refer to Figure 5 Base station 541 can connect to first TRP 501, second TRP 502, and third TRP 503, and can communicate with UE 511 via TRPs 501, 502, and 503. Base station 541 can directly control first TRP 501, second TRP 502, and third TRP 503, or can indirectly control them via another TRP. First TRP 501 can perform DL and / or UL communication with UEs in first cell 510 configured by first TRP 501. Second TRP 502 can perform DL and / or UL communication with UEs in second cell 520 configured by second TRP 502, and third TRP 503 can also perform DL and / or UL communication with UEs in third cell 530 configured by third TRP 503. Figure 5 In the example, UE 511 is shown as being located outside the second cell 520 configured by the second TRP 502; however, this is due to limitations in the accompanying drawings, and in the following description, it is assumed that UE 511 is located within the second cell 520. Additionally, in Figure 5 In the example, UE 511 is shown to be located outside the third cell 530 configured by the third TRP 503, but this is due to the limitations of the figures, and in the following description, it is assumed that UE 511 is located inside the third cell 530.

[0102] Figure 5The example can correspond to an asymmetric mTRP environment. The first TRP 501 can be capable of performing the above reference. Figure 4 The TRPs for DL ​​and UL communication are described above. The first TRP 501 can also be referred to as the "header TRP" or "macro TRP". The second TRP 502 and / or the third TRP 503 can be referred to as "low-power TRPs (LPTs)" and may transmit only limited control information in the downlink. Figure 5 In the example, each of the second TRP 502 and / or the third TRP 503 is shown as transmitting (or broadcasting) a synchronization signal block (SSB) within its cell area 520 or 530.

[0103] As one of the methods proposed in the Work Item Description (WID) of 3GPP Release 19, a method for reducing DL transmissions in micronodes (i.e., LPTs) has been proposed as an option to further reduce energy consumption. Therefore, in the first scenario of an asymmetric mTRP environment, as one of the methods to reduce DL transmissions, the second TRP 502 and / or the third TRP 503 may only transmit SSB and / or Channel State Information Reference Signals (CSI-RS).

[0104] Furthermore, since both the second TRP 502 and the third TRP 503 are located within the first cell area 510 of the first TRP 501, the second TRP 502 and the third TRP 503 can be understood as being controlled by the first TRP 501. In the first scenario of the asymmetric mTRP environment, each of the first TRP 501, the second TRP 502, and the third TRP 503 can have a different Physical Cell Identity (PCI). Figure 5 For example, the first TRP 501 has PCI p, the second TRP 502 has PCI q, and the third TRP 503 has PCI b.

[0105] In the first scenario of the asymmetric mTRP environment, each of the second TRP 502 and the third TRP 503 can save energy by sending only SSB and / or CSI-RS to UE 511. When each of the second TRP 502 and the third TRP 503 sends only SSB and / or CSI-RS to UE 511, as described above, inefficient decoding and issues related to the conditioning of the new Master Information Block (MIB) may arise.

[0106] refer to Figure 5Compared to the first TRP 501 and the second TRP 502, the UE 511 can be closer to the third TRP 503. When the UE 511 attempts initial access, it can receive an SSB from each of the first TRP 501, the second TRP 502, and the third TRP 503. The UE 511 can select the SSB received from the third TRP 503, which is closest to the UE 511, as the optimal SSB among the SSBs received from the first TRP 501, the second TRP 502, and the third TRP 503. In this case, since both the second TRP 502 and the third TRP 503 are LPTs, they can send an SSB to the UE 511 without a MIB to further reduce power consumption. When the LPTs (i.e., the second TRP 502 and the third TRP 503) send an SSB to the UE 511 without a MIB, the following problems may occur.

[0107] UE 511 needs to select the best SSB from the SSBs received from the corresponding TRP and needs to decode the selected best SSB in order to obtain initial synchronization. In this case, when UE 511 selects the SSB received from the third TRP 503 as the best SSB, UE 511 can decode the SSB received from the third TRP 503. However, since the third TRP 503 transmits SSBs that do not include the MIB, even if UE 511 decodes the SSB received from the third TRP 503, UE 511 cannot obtain the MIB. As mentioned above, UE 511 can only determine whether the SSB includes the MIB after decoding the SSB. Therefore, UE 511 may consume unnecessary power to decode the SSB received from the third TRP 503. Furthermore, in order to find an SSB that includes the MIB, UE 511 may need to select another best SSB and perform decoding again on the selected SSB. Therefore, in order to find a suitable SSB, UE 511 may consume unnecessary power.

[0108] As another example, the second TRP 502 and the third TRP 503, acting as LPTs, may send an SSB including a MIB to the UE 511. When the second TRP 502 and the third TRP 503, acting as LPTs, send an SSB including a MIB to the UE 511, the following problems may occur.

[0109] When each of the second TRP 502 and the third TRP 503, which are LPTs, transmits an SSB including a MIB, the UE 511 can receive the SSB and obtain the MIB included in the SSB. Even in this case, the UE 511 can select the SSB received from the third TRP 503 closest to the UE 511 as the best SSB. The UE 511 can decode the SSB received from the third TRP 503 and obtain the MIB included in the SSB. Typically, the MIB may include information for receiving System Information Block 1 (SIB1). However, since the second TRP 502 and the third TRP 503 are LPTs, control information also needs to be transmitted in a minimal amount, so the second TRP 502 and the third TRP 503 may not perform the transmission of SIB1. Therefore, the MIB included in the SSB needs to notify the UE 511 that the configuration of the MIB is different from the configuration of the MIB transmitted by the general TRP. This is because the second TRP 502 and the third TRP 503, acting as LPTs, do not transmit SIB1. In other words, the MIB included in the SSB transmitted by the second TRP 502 and the third TRP 503 needs to notify the UE 511 that the MIB does not include information about SIB1. To notify that the MIB included in the SSB transmitted by the second TRP 502 and the third TRP 503, acting as LPTs, is different from the general MIB, the MIB may require additional time / frequency resources. In other words, there is a need to propose a configuration method for the new MIB.

[0110] Therefore, as Figure 5 The first scenario of the asymmetric mTRP environment shown may not be suitable for improving uplink capacity. However, the problems described above can be solved when the methods proposed in one or more scenarios described below are used. These will be described in detail in other scenarios.

[0111] On the other hand, when using the first scenario in an asymmetric mTRP environment, the second TRP 502 and the third TRP 503 can also indicate, by using fields defined in the current 5G New Radio (NR) specification, that the MIB included in the SSB transmitted by the second TRP 502 and the third TRP 503 is different from the general MIB.

[0112] According to the 5G NR specification, a MIB can consist of multiple fields, and among these fields, there is a field called "cellBarred," which is configured as one bit. When the cellBarred field of the MIB has a value of '1', it indicates that the MIB has not defined a cell, and when the cellBarred field has a value of '0', it indicates that the MIB has defined a cell. In an exemplary embodiment of this disclosure, the cellBarred field of the MIB can be used to indicate whether SIB1 will be transmitted later using the MIB included in the SSB sent by the TRP.

[0113] For example, when the cellBarred field of the MIB has a value of '1', UE 511 can determine that SIB1 has not been sent, and when the cellBarred field of the MIB has a value of '0', UE 511 can determine that SIB1 has been sent. In other words, the second TRP 502 and / or the third TRP 503 can send an SSB that includes the MIB, and can set the cellBarred field of the MIB to have a value of '1' and send the MIB, thereby indicating to UE 511 that SIB1 will not be sent later. Furthermore, the first TRP 501 can send an SSB that includes the MIB, and can set the cellBarred field of the MIB to have a value of '0' and send the MIB, thereby indicating to UE 511 that SIB1 will be sent later. Therefore, in the first scenario of the asymmetric mTRP environment, each TRP can notify UE 511 whether it has sent SIB1 by using the cellBarred field of the MIB, and UE 511 can determine the TRP from which UE 511 can obtain SIB1 by decoding and checking the cellBarred field of the MIB. Thus, UE 511 can identify the TRP that sent SIB1 and can attempt initial access with the TRP that sent SIB1.

[0114] However, even when using the cellBarred field of the MIB, the following problem may still exist: the UE 511 may repeatedly decode the SSB received from the TRP, and each TRP may consume more power to send the SSB.

[0115] When reference Figure 5In describing the above example, the situation is as follows. Each of the first TRP 501, the second TRP 502, and the third TRP 503 can send an SSB including a MIB to the UE 511. In this case, the first TRP 501 can set the value of the cellBarred field of its MIB to '0' and send the MIB, and each of the second TRP 502 and the third TRP 503 can set the value of the cellBarred field of their MIB to '1' and send the MIB. Therefore, the UE 511 can receive an SSB including a MIB from each of the first TRP 501, the second TRP 502, and the third TRP 503, and can decode the MIB and check the value of the cellBarred field. The UE 511, which needs to perform initial access to the base station 541, can determine the TRP used to perform the initial access based on the checked value of the cellBarred field. Figure 5 In this case, UE 511 can select the first TRP 501.

[0116] In the following description, an SSB sent by setting the cellBarred field value to '0' is called a "cell defining (CD) SSB", while an SSB sent by setting the cellBarred field value to '1' is called a "non-cell defining (NCD) SSB".

[0117] When briefly describing the initial system access procedure of UE 511 in the first scenario in an asymmetric mTRP environment, it can be performed as follows.

[0118] When UE 511 is powered on, it can perform initial system access by moving across the frequency synchronization channel (rasterizing) defined in the 5G NR specification to search for the best CD SSB with a signal strength greater than or equal to a specific (or pre-configured) threshold. Searching for the best CD SSB can be understood as searching for the TRP used to perform synchronization. UE 511 can perform DL timing synchronization and frequency synchronization using the best CD SSB and can obtain PCI and MIB from it. Figure 5 In the example, the TRP that sends the best CD SSB can be the first TRP 501. Therefore, UE 511 can obtain the PCI p of the first TRP 501.

[0119] UE 511 can obtain SIB1 from a first TRP 501, which serves as a TRP for performing synchronization, based on information included in the MIB. UE 511 can perform a random access procedure using the first TRP 501, which is the TRP from which it obtained the MIB and SIB1, based on the information obtained from the MIB and SIB1. UE 511 can receive Radio Resource Control (RRC) messages (or RRC configuration messages) from the first TRP 501 through the random access procedure, and can enter an RRC connected state by sending an RRC reconfiguration complete message to the first TRP 501, in which communication with the first TRP 501 is possible.

[0120] According to the current 5G NR specification, an SSB can be transmitted every 20 ms. When UE 511 performs a synchronization grid scan, UE 511 can receive a CD SSB from the first TRP 501 through a frequency resource group (e.g., a bandwidth portion (BWP)). As mentioned above, when UE 511 performs a synchronization grid scan, UE 511 can also receive an NCD SSB from the second TRP 502 and / or the third TRP 503. According to the first scenario of an asymmetric mTRP environment, since UE 511 can receive NCD SSBs from the second TRP 502 and / or the third TRP 503, there may be unnecessary power consumption issues.

[0121] In the first scenario of an asymmetric mTRP environment, in order to prevent UE 511 from receiving NCD SSB from the second TRP 502 and / or the third TRP 503, the second TRP 502 and / or the third TRP 503 can transmit NCD SSB through a frequency resource group (e.g., BWP) that is different from the frequency resource group (e.g., BWP) used by UE 511 when performing synchronous grid scan.

[0122] Uplink-only TRPs (UL-only TRPs) do not send (or broadcast) signals to UE 511 via downlink to notify of their existence. Therefore, a "UL-only TRP" can also be referred to as an "unknown UL-only TRP." Since UL-only TRPs do not send any signals to UE 511, an "out-of-synchronization (OOS)" problem may occur. Furthermore, as mentioned above, when the second TRP 502 and / or the third TRP 503 send an NCD SSB with a BWP different from the BWP sent by the first TRP 501, the second TRP 502 and the third TRP 503 may also become unknown UL-only TRPs. In this disclosure, to resolve the UL OOS problem between the UL-only TRP and the UE, the following method can be used.

[0123] As described above, UE 511 can establish a link connection with the first TRP 501, which transmits the CD SSB. Once the link connection between UE 511 and the first TRP 501 is established, the first TRP 501 can send information related to the LPT controlled (or managed) by the first TRP 501 to UE 511 via RRC and / or Media Access Control-Control Element (MAC-CE) signaling. For example, the first TRP 501 can send information such as the time slot and frequency resource group of the SSB transmitted by the LPT controlled by the first TRP 501, or information about the transmit power of UE 511, to UE 511 via RRC and / or MAC-CE signaling. Here, the information about the transmit power of UE 511 can be, for example, information about the transmit power required when UE 511 transmits the preamble. More specifically, the information regarding the transmission power required for UE 511 to transmit the preamble can be the transmission power information of the NCD SSB transmitted by the second TRP 502 and / or the third TRP 503 as LPT, and / or the transmission power information of the CDSSB transmitted by the first TRP 501.

[0124] UE 511 can receive SSBs transmitted by the second TRP 502 and / or the third TRP 503 based on information included in the RRC and / or MAC-CE signaling (e.g., information about time slots and frequency resource groups). Therefore, UE 511 can obtain the PCI of the TRP that transmitted the optimal SSB among SSBs with signal strength equal to or greater than a pre-configured threshold by measuring the SSBs transmitted by the second TRP 502 and / or the third TRP 503. UE 511 can report the paired optimal SSBs and corresponding PCIs to the first TRP 501 using uplink MAC-CE, RRC signaling, or uplink control indicators (or information) (UCI).

[0125] The first TRP 501 can determine a candidate LPT for which UE 511 will perform UL transmission based on paired SSB and PCI information received from UE 511. The first TRP 501 can determine the path loss (PL) offset of the candidate LPT. Furthermore, the first TRP 501 can send a Physical Downlink Control Channel (PDCCH) command DCI to UE 511 to estimate the timing advance (TA) between UE 511 and the LPT. The PDCCH command DCI can include one or more pieces of information about the resources (e.g., time slots or frequency resource groups) used to transmit a preamble to a specific TRP. Therefore, UE 511 can receive the PDCCH command DCI and can determine the resources for transmitting the preamble by using the information included in the PDCCH command DCI. Subsequently, UE 511 can transmit the preamble to the LPT using the resources indicated by the PDCCH command DCI.

[0126] Each of the second TRP 502 and / or the third TRP 503, serving as the LPT, can receive a preamble from the UE 511 and can calculate the TA between the UE 511 and the second TRP 502 or between the UE 511 and the third TRP 503 using the preamble. Information about the calculated TA can be sent to the UE 511 via the first TRP 501. Therefore, the UL OOS problem between only the ULTRP and the UE can be resolved.

[0127] Subsequently, base station 541 can update the PL offset between the UL-only TRP and the UE. Furthermore, base station 541 can update the Transmission Configuration Indicator (TCI) status, PL offset, or UL transmit power information corresponding to the direction in which the UL-only TRP transmits the SSB. When multiple candidate LPTs exist, UE 511 can be configured not to monitor the Random Access Response (RAR) from the LPTs. Instead of monitoring RARs from candidate LPTs, UE 511 can receive RARs from the first TRP 501. In other words, information updated by base station 541 or the first TRP 501 can be sent to UE 511 via the first TRP 501. If necessary, base station 541 or the first TRP 501 can send RARs to UE 511.

[0128] like Figure 5 As shown, since the PCI of all TRPs belonging to base station 541 are set differently, the above-described operation for resolving the UL OOS problem can be applied to frequency range 2 (FR2) using a directional beam pattern. However, the above-described method for resolving the UL OOS problem can also be applied to frequency range 1 (FR1) using an omnidirectional beam pattern.

[0129] Figure 6This is a conceptual diagram illustrating the second scenario in an asymmetric mTRP environment.

[0130] refer to Figure 6 Base station 641 can connect to first TRP 601, second TRP 602, and third TRP 603, and can communicate with UE 611 via TRPs 601, 602, and 603. Base station 641 can directly control first TRP 601, second TRP 602, and third TRP 603, or can indirectly control them via another TRP. First TRP 601 can perform DL and / or UL communication with UE in first cell 610 configured by first TRP 601. Second TRP 602 can perform DL and / or UL communication with UE in second cell 620 configured by second TRP 602, and third TRP 603 can also perform DL and / or UL communication with UE in third cell 630 configured by third TRP 603. Figure 6 The example shown depicts a scenario where UE 611 is located outside the second cell 620 configured by the second TRP 602. However, this is due to limitations of the accompanying drawings, and in the following description, it is assumed that UE 611 is located within the second cell 620. Furthermore, in Figure 6 The example shown depicts a scenario where UE 611 is located outside of the third cell 630 configured by the third TRP 603. However, this is due to limitations of the accompanying drawings, and in the following description, it is assumed that UE 611 is located within the third cell 630.

[0131] Figure 6 The example can correspond to the case assuming an asymmetric mTRP environment. The first TRP 601 can be as referenced. Figure 4 and Figure 5 The TRP described above is capable of DL transmission and UL reception. For example... Figure 5 As described, the first TRP 601 can also be referred to as the header TRP or macro TRP. Each of the second TRP 602 and the third TRP 603 can be referred to as an LPT and can transmit only limited control information via the downlink. Figure 6 In the example, the second TRP 602 and / or the third TRP 603 may only send (or broadcast) SSBs within the corresponding cell areas 620 and 630.

[0132] Figure 6 The second scenario of the asymmetric mTRP environment shown can be similar to Figure 5 The first scenario of the asymmetric mTRP environment described in [the document]. More specifically, the second TRP 602 and / or the third TRP 603, as LPTs, can only send SSB and / or CSI-RS to reduce DL transmissions. However, in [the context of this scenario]... Figure 5In the first scenario of the asymmetric mTRP environment described, the first TRP 501, the second TRP 502, and the third TRP 503 can each use different PCIs. On the other hand, in Figure 6 In the second scenario of the asymmetric mTRP environment shown, the second TRP 602 and the third TRP 603, which serve as LPTs, can use the same PCI as the first TRP 601, which serves as the head TRP. In other words, in Figure 6 In the second scenario of the asymmetric mTRP environment shown, the first TRP 601, the second TRP 602, and the third TRP 603 can share the same PCI. More specifically, the first TRP 601, the second TRP 602, and the third TRP 603 can each have the same PCI p.

[0133] Figure 6 The second scenario of the asymmetric mTRP environment illustrated may also lead to problems such as requiring the UE to perform unnecessary decoding and requiring the definition of new MIBs, as described above with reference to the first scenario of the asymmetric mTRP environment. Therefore, the second scenario of the asymmetric mTRP environment may not be suitable for improving uplink capacity.

[0134] refer to Figure 6 Each of the first TRP 601, the second TRP 602, and the third TRP 603 can broadcast an SSB. In this case, since both the second TRP 602 and the third TRP 603 are LPTs, they can send an SSB to the UE 611 without a MIB to further reduce power consumption. As another example, each of the second TRP 602 and the third TRP 603 can include a MIB in the SSB, and can be notified that it is a UL-only TRP by using the cellBarred field among the multiple fields included in the MIB. As yet another example, the second TRP 602 and the third TRP 603 can use a different BWP than the one used by the first TRP 601.

[0135] Therefore, when UE 611 is powered on, for initial system access, UE 611 can perform a grid scan on the frequency synchronization channel defined in the 5G NR specification to find the best CD SSB with a signal strength equal to or greater than a specific (or pre-configured) threshold and the highest value. Afterward, UE 611 can enter the RRC connection state with the first TRP601 through a four-step random access (RA) procedure. In other words, UE 611 can establish a link connection through the initial access procedure, thereby entering a connected state capable of communication.

[0136] As described above, according to the 5G NR specification, an SSB can be transmitted every 20ms. When performing a synchronization grid scan, UE 611 can receive the CD SSB from the first TRP 601 via a frequency resource group (e.g., a BWP). When the second TRP 602 and the third TRP 603 do not transmit the SSB via a BWP different from that of the first TRP 601, as referenced... Figure 6 As mentioned above, UE 611 may consume unnecessary power to receive and decode SSBs sent by the second TRP 602 and the third TRP 603.

[0137] When the second TRP 602 and the third TRP 603 transmit SSBs via BWPs different from those of the first TRP 601, the UE 611 can receive information from the first TRP 601 via RRC and / or MAC-CE signaling regarding the resources (e.g., time slot information or frequency resource group information) used by the second TRP 602 and the third TRP 603 respectively in transmitting NCD SSBs.

[0138] UE 611 can receive SSBs transmitted by the second TRP 602 and / or the third TRP 603 based on information included in the RRC and / or MAC-CE signaling (e.g., time slot information or frequency resource group information). Therefore, by measuring the SSBs transmitted by the second TRP 602 and / or the third TRP 603, UE 611 can obtain the PCI of the TRP that transmitted the optimal SSB among SSBs with signal strength equal to or greater than a pre-configured threshold. UE 611 can report information about the paired optimal SSBs and the corresponding PCI to the first TRP 601 using uplink MAC-CE, RRC signaling, or uplink control indicator (or information) (UCI).

[0139] Based on the information received from UE 611 regarding the paired SSB and PCI, the first TRP 601 can determine the candidate LPT that UE 611 will use to perform uplink transmission. Furthermore, the first TRP 601 can determine the PL offset of the candidate LPT. In addition, to estimate the uplink TA between UE 611 and the LPT, the first TRP 601 can send a PDCCH command DCI to UE 611. The PDCCH command DCI may include information about the resources (e.g., one or more of time slot information and frequency resource group information) used to send a preamble to a specific TRP. Therefore, UE 611 can receive the PDCCH command DCI and can determine the resources for sending the preamble by using the information included in the PDCCH command DCI. Thereafter, UE 611 can send the preamble to the LPT using the resources indicated by the PDCCH command DCI.

[0140] The second TRP 602 and / or the third TRP 603, acting as LPTs, can receive a preamble from UE 611 and can calculate the TA between UE 611 and the second TRP 602 or between UE 611 and the third TRP 603. Information about the TA calculated in this way can be sent to UE 611 via the first TRP 601.

[0141] Base station 641 can update the PL offset between the UL TRP and the UE. Furthermore, base station 641 can update the joint / UL TCI state, PL offset, or uplink transmit power information corresponding to the direction in which the UL TRP transmits the SSB. When multiple candidate LPTs exist, UE 611 can be configured not to perform RAR monitoring from LPTs. Instead of monitoring RARs from candidate LPTs, UE 611 can receive RARs from the first TRP 601. In other words, information updated by base station 641 or the first TRP 601 can be sent to UE 611 via the first TRP 601. If necessary, base station 641 or the first TRP 601 can send RARs to UE 611.

[0142] like Figure 6 As shown, since the PCI of all TRPs belonging to base station 641 is configured to be the same, the above-described operation for resolving the UL OOS problem can be applied to FR1 using an omnidirectional beam pattern. However, the above-described method for resolving the UL OOS problem can also be applied to FR2 using a directional beam pattern.

[0143] Figure 7a This is a conceptual diagram illustrating a third scenario in an asymmetric mTRP environment.

[0144] refer to Figure 7a Base station 741 can connect to first TRP 701, second TRP 702, and third TRP 703, and can communicate with UE 711 via TRPs 701, 702, and 703. Base station 741 can directly control first TRP 701, second TRP 702, and third TRP 703, or can indirectly control them via another TRP. First TRP 701 can perform DL and / or UL communication with the UE in first cell 710 configured by first TRP 701. Second TRP 702, as a UL-only TRP, can have a second cell 720 configured by second TRP 702, and third TRP 703, as a UL-only TRP, can also have a third cell 730 configured by third TRP 703. Figure 7aThe example shown depicts a scenario where UE 711 is located outside the second cell 720 configured by the second TRP 702; however, this illustration is due to limitations of the accompanying drawings, and the following description assumes that UE 711 is located within the second cell 720. Additionally, in Figure 7a The example shown depicts a scenario where UE 711 is located outside the third cell 730 configured by the third TRP 703; however, this illustration is due to limitations of the figures, and in the following description, it is assumed that UE 711 is located within the third cell 730. Therefore, UE 711 can perform UL transmissions to the second TRP 702 and / or the third TRP 703.

[0145] As one of the methods proposed in 3GPP Rel-19 WID, as an option to further reduce energy consumption, micronodes (e.g., LPTs) can suspend DL transmissions. In other words, an LPT acting as a UL TRP-only device can be configured not to transmit any signals in the downlink. Figure 7a The third scenario of the asymmetric mTRP environment shown can correspond to a situation where the LPT, acting as a UL-only TRP, does not transmit any signals in the downlink. The advantage of the third scenario in the asymmetric mTRP environment is that the unnecessary decoding operations of the SSB and / or the need to define new MIBs described in the first and second scenarios of the asymmetric mTRP environment are avoided. (Reference) Figure 7a The present disclosure describes a method for improving uplink capacity in a third scenario of an asymmetric mTRP environment.

[0146] In the third scenario of the asymmetric mTRP environment, the following issues need to be addressed. First, the UE may not be able to determine the appropriate uplink transmit power. In other words, the problem is that excessive uplink power may be allocated to the data (or signals) transmitted by the UE in the uplink. From the perspective of the second TRP 702 and the third TRP 703 as LPTs, excessive uplink power may lead to excessive receive power.

[0147] Second, since the second TRP 702 and the third TRP 703, as LPTs, are only UL TRPs that do not transmit any signals, the UE may not be able to recognize the existence of the second TRP 702 and the third TRP 703, and there is a problem that the UE cannot recognize the location of the second TRP 702 and the third TRP 703.

[0148] Third, just like the first and second scenarios of the mTRP environment described above, the UL OOS problem still exists.

[0149] In the case of excessive uplink receive power and unknown location of UL TRPs only, UE 711 may be unable to identify the location of the second TRP 702 and the third TRP 703, which are UL TRPs only, because they do not transmit any physical signals and / or physical channels in the downlink. Specifically, when using beamforming schemes, UE 711 may not only be unable to determine the direction of data or signals to be transmitted, but also its transmit power.

[0150] For example, in Figure 7a In this scenario, when UE 711 transmits a signal to second TRP 702 using the same transmit power used to transmit to first TRP 701, second TRP 702 may receive physical signals and / or physical channels with excessive transmit power from UE 711 because the distance between UE 711 and second TRP 702 is shorter than the distance between UE 711 and first TRP 701. When UE 711 transmits a signal to second TRP 702 using the same transmit power used to transmit to first TRP 701, there is also a problem of strong interference to third TRP 703, which is an adjacent UL-only TRP. This strong interference causes strong interference to neighboring cells around second TRP 702, and as a result, the goal of improving uplink capacity may not be achieved.

[0151] Furthermore, due to the UL OOS issue, since UL TRP only does not transmit any physical signals or physical channels in the downlink, UE 711 may not be able to determine the timing of transmitting physical signals (or physical channels) to be sent to UL TRP only.

[0152] When UE 711 transmits a signal to a ULTRP (e.g., the second TRP 702) at the same transmission timing as when UE 711 transmits a signal to the first TRP 701, the second TRP 702 may not receive the signal transmitted by UE 711 due to a UL OOS problem. More specifically, according to the 3GPP communication system specification, the signal transmitted between the transmitting and receiving nodes can be generated by copying the last part of the data to be transmitted and adding the copied part as a cyclic prefix (CP) to the header of the data to be transmitted. When UE 711 transmits a signal to a ULTRP (e.g., the second TRP 702) at the same transmission timing as when UE 711 transmits a signal to the first TRP 701, the second TRP 702 may receive the signal at ±0.5T. CP The signal transmitted by UE 711 is received outside the receptive range. Here, T CPIt can indicate the transmission duration of a CP of a physical signal or a symbol of a physical channel transmitted by the UE 711.

[0153] When the second TRP 702 is at ±0.5T CP When a signal transmitted by UE 711 is received outside the receptive range of the second TRP 702, the orthogonality of the received signal cannot be guaranteed. Therefore, even if the second TRP 702 receives a signal transmitted by UE 711, the second TRP 702 may be unable to demodulate the received signal. This problem may prevent the goal of increasing the uplink capacity of the mobile communication system from being achieved.

[0154] Because the signal received from UE 711 at the second TRP 702, which is a UL-only TRP, has a very high signal-to-noise ratio (SNR), uplink capacity can be improved when the UL OOS problem is resolved. In other words, resolving the ULOOS problem may be very important.

[0155] Figure 7b This is a timing diagram showing the transmission and reception timing of signals between the UE and the TRP in the third scenario of an asymmetric mTRP environment.

[0156] refer to Figure 7b T00 can indicate the assumed Tx time point at the UE. Furthermore, T04 can indicate the Rx time point at the UE 711 for the signal from the first TRP 701. Therefore, the duration from T00 to T04 can correspond to the round-trip delay between the first TRP 701 and the UE 711. In other words, the duration can correspond to the time delay from the time the UE 711 receives the signal transmitted by the first TRP 701 to the time the UE 711 receives the signal again transmitted by the first TRP 701.

[0157] T01 can indicate the assumed Rx time point of the signal from UE 711 in OOS state at the third TRP 703, and T02 can indicate the assumed Rx time point of the signal from UE 711 in sync state at the second TRP 702. Furthermore, T03 can indicate the assumed common Tx / Rx time point of all TRPs 701, 702, and 703.

[0158] The above reference Figure 7a and Figure 7bThe third scenario of the described asymmetric mTRP environment corresponds to the worst-case scenario, where the location of UE 711 attempting initial access to the system is in an OOS state. When the location of UE 711 attempting initial access to the system is not in an OOS state, UE 711 can smoothly perform initial access (or connection) with UL TRP only. The following describes the problems that may occur even when the location of UE 711 attempting initial access to the system is not in an OOS state, as well as the problems that may occur during UE mobility.

[0159] Figure 8a This is a conceptual diagram of the first sub-scene of the third scenario, illustrating an asymmetric mTRP environment.

[0160] refer to Figure 8a UE 811 can represent a UE located at its initial UE position, and UE 812 can represent the same UE after movement, as indicated by reference numeral 850. Base station 841 can be connected to first TRP 801, second TRP 802, and third TRP 803, and can communicate with UE 811 via TRPs 801, 802, and 803. Base station 841 can directly control first TRP 801, second TRP 802, and third TRP 803, or can indirectly control them via another TRP. First TRP 801 can perform DL and / or UL communication with UEs within a first cell 810 configured by first TRP 801. Second TRP 802, as a UL-only TRP, can have a second cell 820 configured by second TRP 802, and third TRP 803, as a UL-only TRP, can also have a third cell 830 configured by third TRP 803. First TRP 801 can be a macro TRP.

[0161] according to Figure 8a For example, UE 811 can establish a connection with a first TRP 801, which is a macro TRP, and thereafter, UE 811 can connect to a second TRP 802, which is a UL-only TRP, and a third TRP 803, which is another UL-only TRP. In this case, when UE 811 moves from the initial position indicated by reference numeral 850 and enters the area of ​​the third TRP 803, which is the new position, a reference hop may occur. Figure 7a The aforementioned OOS issue. (See reference...) Figure 8b and Figure 8c Describe the OOS problem.

[0162] Figure 8b This is a timing diagram showing the transmission and reception timing of signals between the UE and TRP at the initial position of acquiring synchronization in the first sub-scenario of the third scenario in an asymmetric mTRP environment.

[0163] refer to Figure 8b According to the first sub-scenario of the third scenario in the asymmetric mTRP environment, UE 811 at the initial position can be in a state of synchronization with all TRP acquisitions. For example... Figure 8b As shown, T10 can indicate the assumed Tx time point at the UE.

[0164] Furthermore, T14 can indicate the Rx time point of the signal from the first TRP 801 at the UE. Therefore, the duration 861 from T10 to T14 can correspond to the round-trip delay between the first TRP 801 and the UE 811. In other words, the duration can correspond to the time delay from the time point when the UE 811 receives the signal sent by the first TRP 801 to the time point when the UE 811 receives the signal again sent by the first TRP 801.

[0165] exist Figure 8b In this diagram, T11 can indicate the Rx time point of the signal from UE 811 in the synchronization state at the third TRP, T12 can indicate the Rx time point of the signal from UE 811 in the synchronization state at the second TRP 802, and T13 can indicate the Rx reference time. Therefore, the duration 862 from T10 to T13 can correspond to the propagation delay between the first TRP 801 and UE 811. T14 can indicate the Rx time point of the signal from the first TRP 801 at UE 811.

[0166] Figure 8c This is a timing diagram showing the transmission and reception timing of signals between the UE and the TRP in the first sub-scenario of the third scenario of an asymmetric mTRP environment, when the UE moves from the initial position of acquiring synchronization.

[0167] refer to Figure 8c According to the first sub-scenario of the third scenario in the asymmetric mTRP environment, UE 811 can represent the UE located at the initial position, and this UE can move as indicated by reference numeral 850. Therefore, UE 812, representing the same UE after the move, can enter the third cell 830 of the third TRP 803. When UE 812 moves in this manner and moves into the third cell 830 configured by the new UL-only TRP (i.e., the third TRP 803), synchronization between the third TRP 803 and UE 811 may not be maintained.

[0168] exist Figure 8c In this context, T20 can indicate the assumed Tx time point at the mobile UE 812. T21 can indicate the Rx time point at the third TRP 803 for signals from the mobile UE 812 in an OOS state. Figure 8b In contrast, the mobile UE 812 can change from a synchronized state with the third TRP 803 to an OOS state. Furthermore, T22 can indicate the Rx time point of the signal from the mobile UE 812 in the synchronized state at the second TRP 802, and T23 can indicate the Rx reference time. Therefore, the duration 872 from T20 to T23 can correspond to the propagation delay between the first TRP 801 and the UE 812. Additionally, T24 can indicate the Rx time point of the signal from the first TRP 801 at the mobile UE 812.

[0169] As described above, to prevent strong interference to neighboring cells and to resolve reception failures caused by the unknown location of the UL TRP (Ultra-Ultra-TRP) that does not transmit any signals in the downlink (hereinafter referred to as the unknown UL TRP problem) and uplink asynchrony (OOS), it is necessary to determine the PL offset. Furthermore, it is necessary to determine the sounding reference signal (SRS) transmitted by the UE in the uplink and / or the random access (RA) preamble transmitted by the UE in the uplink based on beam scanning via the Physical Random Access Channel (PRACH), and the transmission timing (TT) offset used for them.

[0170] In the following description, for ease of description, the RA preamble may be referred to as a preamble. Therefore, in this disclosure, unless a different preamble is specifically mentioned or it is necessary to distinguish another preamble from the RA preamble, the preamble may be understood as the RA preamble. However, this is merely an example, and it should be noted that any type of preamble may be used, as long as it is capable of performing the operations and procedures according to the present disclosure.

[0171] In the following description, refer to the following as needed. Figure 7a and Figure 7b The third scenario and reference of the asymmetric mTRP environment described Figures 8a to 8c The first sub-scenario of the third scenario of the described asymmetric mTRP environment can be referred to as and described as the 'asymmetric uplink scenario'.

[0172] Figure 9 This is a timing diagram illustrating the case where an OOS problem is sent at only UL TRP and the minimum absolute value of asynchronous operations.

[0173] refer to Figure 9 The diagram illustrates the timing for transmitting DL signals and UL signals between macro TRP (MTRP) 901, UL-only TRP 902, and UE 903. Initially, MTRP 901 and UL-only TRP 902 can be separated by A meters, and MTRP 901 and UE 903 can be separated by B meters.

[0174] The timing of transmitting the DL signal is described. MTRP 901 can transmit the DL signal to UE 903 at an absolute time point. In this case, the DL signal transmitted by MTRP 901 can be received at UE 903 after a first time delay τ1 indicated by reference numeral 911 from the absolute time point. Furthermore, after a second time delay τ2 indicated by reference numeral 912 from the absolute time point, the DL signal transmitted by MTRP 901 can be received at UL MTRP 902 only.

[0175] Next, the first timing of UE 903 sending the UL signal to MTRP 901 is described.

[0176] UE 903 may transmit a UL signal to MTRP 901 via UL-only TRP 902 at a time point (e.g., prior to the time point of the first TA (TA1) set by MTRP 901). The value of the first TA may be set based on the TA value set by MTRP 901 so that UE 903 transmits the UL signal to MTRP 901. Reference numeral 921 may indicate twice the first time delay τ1. Furthermore, reference numerals 922 and 923 may indicate the first time delay τ1 corresponding to half of TA1 based on absolute time. Reference numeral 924 may indicate a second time delay τ2 until the UL signal transmitted by UE 903 is received at UL-only TRP 902. Therefore, reference numeral 925 may correspond to the TA offset Δ, which is the difference between the first time delay τ1 and the second time delay τ2. TA .

[0177] Next, the second timing for UE 903 to send the UL signal to the uplink-only TRP 902 is described.

[0178] UE 903 may send a UL signal to UL-only TRP 902 at a time point (e.g., a time point prior to the second TA (TA2) set between UE 903 and UL-only TRP 902). Reference numeral 931 may indicate a second time delay τ2 from the time point prior to TA2 to the absolute time point. Reference numeral 933 may indicate a first time delay τ1 corresponding to half of TA1 based on the absolute time. Therefore, TA2 can be determined as the sum of the first time delay τ1 and the second time delay τ2. In this case, when the TA offset Δ is the difference between the first time delay τ1 and the second time delay τ2... TA The absolute value is greater than time T CP When half of the CP (which was sent during its duration) is in the OOS state, an OOS state will occur.

[0179] Therefore, to prevent OOS at UL-only TRP 902, UE 903 needs to send the UL signal at a time point earlier than TA2, so that the UL signal is sent to UL-only TRP 902, and TA2 needs to be earlier than TA1 by a factor of T. CP Half of the corresponding TA offset Δ TA The time point, where TA1 is the TA value between MTRP 901 and UE 903.

[0180] The above method corresponds to the case where UE 903 can use a first TA (TA1) and a second TA (TA2), where the first TA (TA1) is the timing information used to send the UL signal to MTRP 901, and the second TA (TA2) is the timing information used to send the UL signal to UL-only TRP 902. When UE 903 cannot use both TA values ​​to resolve the UL OOS problem (i.e., when UE 903 can only use a single TA value), if it is necessary to determine the PL offset by sending SRS to MTRP 901, or if UE 903 needs to send the UL signal to UL-only TRP 902, a UL OOS problem may occur between UE 903 and UL-only TRP 902.

[0181] In an asymmetric scenario with one mTRP 901, one UE 903, and only UL TRP 902, reference numeral 925 can indicate a situation where an OOS occurs at only UL TRP 902. Furthermore, as mentioned above, to prevent OOS, the TA2-based transmission timing (TT) needs to be 'TA1–Δ'. TA ', and Δ TA It needs to have a value greater than T CP Half of the value.

[0182] The following describes methods for solving such problems. Figure 7a and Figure 7b The methods described in the third scenario of the asymmetric mTRP environment shown are for addressing the following issues: excessive uplink receive power, unknown location of UL TRP only, and UL OOS problem.

[0183] Figure 10a This is a sequence diagram illustrating the initial access procedure of the UE in the third scenario of an asymmetric mTRP environment, and Figure 10b This is a sequence diagram illustrating the uplink transmission of the UE in the third scenario of an asymmetric mTRP environment.

[0184] Figure 10a and Figure 10b The process can be a continuous process, in which the execution Figure 10a Execute after the process Figure 10b The process, or Figure 10a and Figure 10b The process can be executed separately. In this disclosure, for ease of description, it is assumed that during the execution... Figure 10a Execute after the process Figure 10b The process is a continuous process. Furthermore, in the following description, the network in the third scenario of the asymmetric mTRP environment may include a first TRP as a macro TRP, multiple UEs (UE #0, ..., and UE #U−1), and only UL TRPs (i.e., only UL TRP #1, ..., and only UL TRP #M). Furthermore, in the following description, for ease of description, the operation of UE #0 among the multiple UEs is described as an example. Furthermore, in the only UL TRPs, the operations of only UL TRP #1 and only UL TRP #M are described as examples.

[0185] First, refer to Figure 10a Step S1000 can be an initial access establishment procedure. In step S1001, the first TRP, acting as a macro TRP, can transmit (or broadcast) beamformed SSBs in multiple directions. Therefore, UE #0 can receive beamformed SSBs in multiple directions from the first TRP. UE #0 can obtain downlink synchronization by using one of the received SSBs. The SSBs transmitted by the first TRP can be transmitted periodically or aperiodically for initial synchronization and maintenance of the beamformed downlink. When beamforming is not used, the first TRP can transmit (or broadcast) one or more SSBs in a specific frequency band. For example, when the first TRP transmits (or broadcasts) SSBs in a sub-6 GHz frequency band, the first TRP can simply transmit (or broadcast) a quasi-omnidirectional SSB or multiple SSBs with a given directionality without using beamforming.

[0186] In step S1002, UE #0 may be in a downlink synchronization state using an SSB. UE #0 may obtain the MIB included in the SSB used to obtain downlink synchronization. The MIB may be transmitted to UE #0 by being carried on the Physical Broadcast Channel (PBCH). In the case of UE #0 performing the initial access establishment procedure, the MIB may correspond to the first system information obtained by UE #0, and may also be referred to as the first RRC message. The MIB may include information indicating the location of the time and frequency resources for transmitting SIB1.

[0187] In step S1003, the first TRP, acting as the macro TRP, can periodically broadcast SIB1. In step S1003, UE#0 can receive SIB1 sent from the first TRP based on information obtained from the MIB. Here, SIB1 can be sent to the UE by carrying it on the Physical Downlink Shared Channel (PDSCH). SIB1 can correspond to the second system information obtained by the UE and can be referred to as the second RRC message.

[0188] During the initial access procedure, the first TRP can send all SIBs except SIB1 to the UE via PDSCH. When the first TRP intends to send other SIBs via PDSCH, it can include scheduling and control information for SIB2 in SIB1 sent via PDSCH to notify the UE that other SIBs are scheduled after SIB1. In this way, SIB2 can also be sent via PDSCH including scheduling and control information for SIB3. This method can be applied in the same way up to SIBy that the first TRP intends to send.

[0189] When intending to perform the initial access procedure quickly, the first TRP may not send multiple SIBs other than SIB1 during the initial access procedure. When multiple SIBs other than SIB1 are not sent during the initial access procedure, the first TRP can send control information indicating that multiple SIBs other than SIB1 were not sent in SIB1 via PDSCH. When UE #0 is in an RRC connection state with the first TRP, or during the RRC reconfiguration process after the first TRP sends RRC reconfiguration indication information to UE #0, information about multiple SIBs other than SIB1 can be sent, in whole or in part, as SIBy. After UE #0 requests information about SIBs other than SIB1 from the first TRP, information about SIBs other than SIB1 can also be sent to UE #0 in response to a request from UE #0. In this disclosure, for ease of description, the case where only SIB1 is obtained during the initial access phase is assumed and described. However, this is merely for the convenience of describing this disclosure, and this disclosure is not limited thereto.

[0190] UE #0, having received system information (e.g., MIB and SIB) from the first TRP through steps S1001 to S1003, can perform a random access (RA) procedure. Step S1010, included in step S1000, can be a contention-based random access establishment procedure. RA procedures can be classified as contention-based random access (CBRA) procedures and contention-free random access (CFRA) procedures. During the initial access process, the UE can perform a CBRA procedure.

[0191] In step S1011, UE #0 can randomly select a preamble from all preambles provided by the first TRP and then send the selected preamble to the first TRP via PRACH. In the 3GPP 5G NR specification, the preamble can be referred to as message 1 (Msg1). In this case, the beam direction of Msg1 can be the uplink direction corresponding to the beam direction of receiving SSB in the downlink. The resources for sending the preamble can be determined based on the association information between RACH and SSB obtained in advance from SIB1 (e.g., RACH timing (RO)). Here, RO can indicate the specific time slot and frequency resources for transmitting RACH. In LTE and 5G NR, RACH transmission is possible in various subframes or time slots, so RO can indicate the specific timing and frequency resources for transmitting RACH messages. RO can represent the timing of transmitting a RACH sequence at a specific time, and RO can be provided to the UE using system information (e.g., SIB1) broadcast by the first TRP (or network (e.g., base station)).

[0192] RACH can be transmitted using specific frequency resources, which can be indicated (or specified) by a first TRP (or the network). Therefore, a UE can send RACH messages within the frequency resources and time slots indicated by the first TRP. RACH can be shared by all UEs, and collisions may occur between RACH messages sent by different UEs when all UEs randomly attempt RACH. Therefore, ROs can be used to reduce these collisions and improve the efficiency of the RACH process. Since a UE can send a RACH request at a time precisely synchronized with the first TRP via an RO, network resources can be used more efficiently. Therefore, in LTE and 5G NR, an RO can indicate the specific time and frequency resources where a RACH process can occur. ROs can be an important element in helping UEs effectively access the base station.

[0193] In step S1011, the first TRP can detect whether a preamble has been sent from the UE based on SIB1 association information (e.g., RO). The preamble can notify the first TRP of the existence of a UE that needs uplink synchronization, and at the same time, the preamble can be used to estimate the propagation delay between the UE and the first TRP.

[0194] Additionally, when UE #0 transmits the preamble in step S1011, UE #0 may not know the appropriate transmission power for the preamble beforehand. Therefore, UE #0 can estimate the required power based on the PL measured via the downlink and information about the transmission power of the first TRP obtained from SIB1, and then determine the transmission power of the preamble based on the estimated power. Furthermore, UE #0 can configure a window for receiving a response signal from the first TRP after transmitting Msg1. The response signal received from the first TRP can be a Random Access Response (RAR), and the window used to receive the response signal can be called the RAR window. When UE #0 does not receive a RAR from the first TRP within the RAR window, UE #0 can determine that the transmission of Msg1 has failed. Then, UE #0 can retransmit the preamble by setting the transmission power of the preamble to a higher value.

[0195] In step S1012, the first TRP can determine whether a preamble exists in the signal received via PRACH. As described in step S1011, since the preamble is randomly selected and sent by UE #0, it is impossible to specify which UE sent which preamble through preamble detection. Therefore, even if a preamble is detected in the RO, the first TRP may not be able to identify how many UEs used the detected preamble. In step S1012, the first TRP can generate a RAR based on the index of the detected preamble. The RAR can be sent to the UE using a PDCCH scrambled with a Random Access Radio Network Temporary Identifier (RA-RNTI).

[0196] UE #0 and the first TRP can calculate the RA-RNTI using the time and frequency resources of the RO (Relationship of the Preamble). In this case, the PDCCH is mapped to the Common Search Space (CSS) indicated by SIB1 pre-obtained by UE #0, and the time and frequency resource location of the PDCCH is not fixed but located at a position within the search space of the CSS. Therefore, UE #0 needs to perform blind decoding of the PDCCH at candidate positions within the CSS. Due to the blind decoding of the PDCCH, the UE's power consumption may increase.

[0197] RARs may include RA preamble identifiers (RAPID), timing advance / adjustment / alignment commands (TAC), UL authorization, temporary cell radio network temporary identifiers (TC-RNTI), timing advance / adjustment / alignment group (TAG) identifiers (ID), and asymmetric indicators.

[0198] Here, TAC can refer to a value used to compensate for the estimated timing error when the first TRP receives Msg1 for uplink synchronization, and UL authorization can refer to information indicating the allocation of uplink resources for UE #0 to send message 3 (Msg3) to the first TRP, as described in step S1013 below. TC-RNTI can be an RNTI temporarily allocated to UE #0 and can be used for the transmission and reception of Msg3 and message 4 (Msg4), as described in step S1014 below. Additionally, TAG ID can be an ID related to the transmission timing of the UL signal transmitted via the link between UE #0 and the first TRP.

[0199] When UE #0 executes step S1012 for the first time during the CBRA process, the TAG ID value can be set to the default value (i.e., '0'). On the other hand, when step S1012 in the CBRA process is not for the serving cell, the TAG ID value can be set to '1' to indicate that the CBRA process is not for the serving cell. Furthermore, the TAG ID in step S1012 can be the same as or different from the TAG ID in the UL Transport Configuration Indicator (TCI) status message.

[0200] The asymmetric indicator can be configured to allow UE #0 to identify the CBRA. Step S1012 is applied as follows: Figure 7a or Figure 8a The fields described in the section on asymmetric uplink scenarios. The asymmetric indicator field can be configured to 1 bit. For example, when the value of the asymmetric indicator field is set to '0', the value can indicate that the scenario is not an asymmetric deployment scenario, and when the value of the asymmetric indicator field is set to '1', the value can indicate that step S1012 of CBRA is applied to an asymmetric deployment scenario. In this case, the field value is merely an example, and the field value can be configured to be interpreted in the opposite way.

[0201] The TAG ID can be reused to indicate one of two TA values. More specifically, when the TA value estimated in step S1011 of the CBRA indicates that the first TRP and UE #0 are in a synchronized state (i.e., not in an OOS state), the TAG ID value can be set to '0', such that the TA value between the first TRP and UE #0 is applied to uplink transmission. On the other hand, when the first TRP and UE #0 are in an OOS state, the TAG ID value can be set to '1', such that the value obtained by subtracting the TA offset value from the TA value between the first TRP and UE #0 is used for uplink transmission.

[0202] Furthermore, the 1-bit TAG ID field of the Rel-18 RAR can be used to distinguish between a first link connected to a first TRP that is a macro TRP (corresponding to TAG ID 0) and a second link connected to a UL-only TRP (corresponding to TAG ID 1). Additionally, the 1-bit TAG ID field of the Rel-18 RAR can be specified in the MAC-CE message for the activated / indicated joint / UL TCI status within the Unified TCI framework.

[0203] In asymmetric scenarios in Rel-19, supporting two TAs may be intended to determine whether the TA difference between the first and second links falls within the OOS range. When aiming to distinguish whether the TA difference between the first and second links is within the OOS range, the TAG IDs defined in Rel-18 may not be suitable for use as is in Rel-19. This is because when the TA value of the second link is almost identical to the TA value of the first link, it may be preferable to map the second link to TAG ID 0 corresponding to the TA value of the first link. However, in Rel-18, such mapping is not possible due to the support of coresetPoolIndex. To address this issue, it is proposed to add a new 1-bit Asym (asymmetric) indicator field to RAR and MAC-CE messages in Rel-19. When the bit of the Asym indicator field proposed in this disclosure is set to '0', UE #0 needs to support the two TA extensions defined for TAG IDs in Rel-18. When the Asym indicator field bit is set to '1', mapping TAG ID 0 to the second link is allowed if the TA values ​​of the two links are nearly identical. This approach has the advantage of reducing the resource waste in sending absolute TAC commands from the first TRP to UE #0 via MAC-CE for updating uplink synchronization of UE #0. An overview according to this disclosure is as follows.

[0204] ● A new 1-bit field can be specified for RAR messages and the MAC-CE format used to activate or indicate the joint / UL TCI status in the Unified TCI framework.

[0205] The bit field index 0 of this field can indicate support for the two TA extensions defined for TAG ID in Rel-18.

[0206] >This field's bit field index 1 can indicate whether the TAG ID can be set to be the same or different based on the TA difference between the connected links.

[0207] In step S1013, UE #0 can send an RRC Establishment Request (RSR) message and an ID (hereinafter referred to as UE ID) that identifies UE #0 to the first TRP using uplink radio resources indicated by the UL authorization included in the previously received RAR. In this case, the RSR message and UE ID can be scrambled with TC-RNTI and sent via PUSCH. Therefore, the first TRP can receive the TC-RNTI scrambled RSR message and UE ID from UE #0 via PUSCH. In step S1013, when more than one UE sends the same preamble in step S1011, that is, when a preamble collision occurs, all UEs sending the same preamble can refer to the same RAR and can send the TC-RNTI scrambled RSR message and the corresponding UE ID using the same radio resources. That is, when two or more UEs send Msg3 to the first TRP, a Msg3 collision may occur.

[0208] All UEs that send the same preamble in step S1011 may eventually send Msg3 in step S1013, and collisions may occur between Msg3s. When sending Msg3 to the first TRP, each UE can operate a contention resolution timer to identify whether the Msg3 sent by the UE has experienced a collision or has been successfully decoded at the first TRP.

[0209] Step S1014 can correspond to the second process for resolving contention. In step S1014, the first TRP can decode the received Msg3, and for a successfully decoded message, the first TRP can send a Contention Resolution Identifier (CRI) message to UE #0 via the PDSCH CRI MAC-CE. When the first TRP successfully decodes Msg3, the first TRP can send Msg4, which includes uplink grant information, to UE #0, thereby allowing the execution of the general transmission process between UE #0 and the first TRP. Furthermore, Msg4 may include a message for RRC establishment and can be sent to UE #0 via the PDSCH.

[0210] When UE #0 receives a CRI message before the contention resolution timer operated in step S1013 expires, UE #0 can consider (or determine) that the RA procedure has been successfully executed. Then, UE #0 can regard TC-RNTI as UE #0's C-RNTI so that it can continue to use TC-RNTI in the system connected state.

[0211] If UE #0 fails to receive a CRI message before the contention resolution timer expires in step S1013, or if the CRI message received before the contention resolution timer expires does not match the UE identity included in Msg3, UE #0 can determine that the transmission of Msg3 in step S1013 has failed. When UE #0 determines that the transmission of Msg3 has failed, UE #0 can retry the 4-step CBRA establishment procedure after performing a backoff. That is, UE #0 can restart from step S1011.

[0212] The first TRP defines the maximum number of RA attempts to prevent RACH channel congestion. If random access is not successfully performed within the maximum number of attempts, the UE can abandon the RA procedure and start downlink synchronization again from scratch.

[0213] In step S1021, UE #0, having successfully completed the RA procedure, can send a Hybrid Automatic Repeat Request (HARQ) ACK or NACK message to the first TRP via PUCCH. The ACK or NACK message indicates whether the message has been received correctly. Furthermore, UE #0 can send a registration request to the Access and Mobility Management Function (AMF) via the Non-Access Stratum (NAS) layer. Here, the NAS layer can be the layer used for signaling between UE #0 and the core network, rather than the layer used for signaling between UE #0 and the first TRP. Subsequently, authentication and security procedures can be performed via the NAS layer, and the AMF can send a registration acceptance message to UE #0 via the first TRP.

[0214] In step S1022, the first TRP can send the RRC reconfiguration message together with the registration acceptance message received from the AMF to UE #0. Therefore, UE #0 can receive the registration acceptance message from the AMF, and UE #0 can receive the RRC reconfiguration message from the first TRP.

[0215] In step S1023, UE #0 can send an RRC reconfiguration complete message and a registration complete message to the first TRP. Afterward, UE #0 can enter the RRC connection state, in which UE #0 can send data to and receive data from the first TRP.

[0216] Figure 11 This is a conceptual diagram illustrating the completion of RRC configuration between the UE and the first TRP in a third scenario of an asymmetric mTRP environment.

[0217] refer to Figure 11 Base station 1141 can communicate with UE 1111 in the cell located at base station 1141 using multiple TRPs 1101, 1102, and 1103. Figure 11 In the example, for the sake of simplicity, only three TRPs 1101, 1102, and 1103 are shown, but the number of TRPs that can be included in base station 1141 is not limited to three. That is, base station 1141 can include one TRP, two TRPs, or four or more TRPs. However, since this disclosure describes an mTRP environment, the case where base station 1141 includes only one TRP is not considered.

[0218] exist Figure 11 In an exemplary embodiment, it is assumed that a base station 1141 includes three different TRPs. The first TRP 1101 may have a first cell area 1110, the second TRP 1102 may have a second cell area 1120, and the third TRP 1103 may have a third cell area 1130. For example... Figure 11 As shown, the first cell area 1110 formed by the first TRP 1101 can be the cell with the widest area, and the first cell area 1110 can include both the second cell area 1120 and the third cell area 1130.

[0219] Figure 11 The first TRP 1101 shown can be referred to as a macro TRP or header TRP as described above, and the first TRP 1101 can perform DL and UL communication with UE 1111. Furthermore, the second TRP 1102 and the third TRP 1103 can be the UL-only TRPs described above. Therefore, the second TRP 1102 and the third TRP 1103 can be TRPs that do not transmit signals in the downlink, or they can be TRPs that transmit only minimal downlink signals.

[0220] Figure 11 The UE 1111 shown can correspond to Figure 10a The UE 1111 described herein is UE #0, and UE 1111 can be in a state where step S1000 has been executed using the first TRP. Furthermore, UE 1111 illustrates the case where, after executing steps S1021 and S1022, UE 1111 sends an RRC reconfiguration completion message in step S1023. That is, in Figure 11 The diagram can be used to illustrate the situation where UE 1111 sends an RRC reconfiguration complete message to the first TRP 1101 and enters the RRC connection state.

[0221] Next, refer to Figure 10b Describe the process of UE #0 performing uplink transmission. Because... Figure 10bThis is a sequence diagram of the UE's uplink transmission in the third scenario of an asymmetric mTRP environment, so the first TRP can be either a macro TRP or a header TRP. Furthermore, UE #0 can be in an RRC connection state with the first TRP, such as... Figure 10a As shown. Furthermore, in addition to the first TRP, the TRPs can be UL TRPs only.

[0222] although Figure 10b Not shown in the image, but during execution Figure 10b Previously, the first TRP and UE #0 could perform the procedures required for path loss (PL) calculation. To address reception failures caused by strong uplink interference to or from neighboring cells, unknown UL-only TRP locations, and uplink OOS in the third scenario of asymmetric mTRP environments, the first TRP can broadcast a PL-reference signal (PL-RS) when necessary and / or periodically. Therefore, UE #0 can receive the PL-RS from the first TRP. UE #0 can then calculate the DL PL from the first TRP to the UE based on the PL-RS received from the first TRP.

[0223] Assume UE #0 is described by calculating DL PL as described above. Figure 10b The process. However, it can also be executed when UE #0 does not calculate DL PL. Figure 10b The process.

[0224] In step S1030, the first TRP may instruct (or inform) UE #0 to perform beam scanning of the SRS or preamble. Therefore, UE #0 can receive a signal from the first TRP instructing (or informing) UE #0 to transmit the SRS or preamble via beam scanning. Various signals can be used as signals to instruct (or inform) UE #0 to perform beam scanning of the SRS or preamble. For example, one of the DCIs used in the current 5G NR specifications can be used, or a newly defined message can be used. Using a DCI as a signal to instruct (or inform) UE #0 to perform beam scanning of the SRS or preamble is merely an exemplary embodiment, and this disclosure is not limited thereto. For example, an RRC signaling message may indicate transmission within a specific time period, or when two or more time periods are configured via RRC signaling, MAC-CE may indicate that a time period is activated.

[0225] In step S1040, UE #0 may transmit SRS or a preamble by beam scanning in a predefined (or preconfigured) direction based on instructions from the first TRP. Since it is impossible to know which of the UL TRPs #1, ..., and UL TRP #M receives the SRS or preamble transmitted by UE #0 in step S1040, it should be noted that... Figure 10bThis illustrates the case where the signal from step S1040 is redundantly sent to only the UL TRP.

[0226] In this scenario, UE #0 can use the transmit power towards the first TRP calculated according to PL-RS and DL PL as is, as is, the transmit power of the SRS or preamble. As another example, UE #0 can use the transmit power applied by UE #0 in step S1013 during the RA procedure as is, as is, the transmit power of the SRS or preamble. As yet another example, UE #0 can use the transmit power obtained by modifying the transmit power applied by UE #0 in step S1013 during the RA procedure as the transmit power of the SRS or preamble. UE #0 can transmit a UL physical signal (or UL physical channel) spatially correlated with or beamformed to the first TRP.

[0227] Furthermore, since UE #0 is unaware of the location of the UL TRP only, UE #0 can transmit the UL signal performing beam scanning in a predefined direction at the aforementioned transmit power. Alternatively, UE #0 can transmit the SRS or preamble using the (initial) transmit power received from the first TRP as is. Yet another method, UE #0 can use a modified power to transmit the SRS or preamble. Therefore, the UL signal used for beam scanning can be either an SRS or a PRACH preamble, and one of the beam scanning signals can be transmitted towards the first TRP.

[0228] Before UE #0 performs beam scanning, the first TRP may instruct UE #0 to perform beam scanning using SRS and / or preamble based on given conditions (e.g., the number of UL signals for each beam scan and the transmission timing for each group).

[0229] Each UL-only TRP (i.e., UL-only TRP #1, ..., and UL-only TRP #M) can calculate the UL receive power and receive timing based on the spatial SRS / preamble associated with UE #0 received from UE #0 in step S1040.

[0230] In steps S1051 and S1052, each UL-only TRP (i.e., UL-only TRP #1, ..., and UL-only TRP #M) can send the UL receive power and receive timing calculated based on the spatial SRS / preamble associated with UE #0 to the first TRP, which is either a macro TRP or a header TRP. Therefore, in steps S1051 and S1052, the first TRP, which is either a macro TRP or a header TRP, can receive the UL receive power and receive timing based on the spatial SRS / preamble associated with UE #0 from each UL-only TRP (i.e., UL-only TRP #1, ..., UL-only TRP #M).

[0231] The first TRP can determine one or more UL-only TRPs based on the UL receive power and receive timing of the spatial SRS / preamble associated with UE #0 received from the corresponding UL-only TRP.

[0232] In step S1060, the first TRP can send to the corresponding UE (e.g., UE #0) mapping information between one or more UL TRP-only related PL offsets, TT offsets, and PL / TT offsets and uplink TCIs determined for a specific UE (e.g., UE #0). Therefore, in step S1060, UE #0 can receive from the first TRP the mapping information between one or more UL TRP-only related PL offsets, TT offsets, and PL / TT offsets and uplink TCIs.

[0233] Although step S1060 is in Figure 10b While step S1060 is shown as a single step, it can actually be configured as two or three steps based on the following description. For example, the transmission can be performed via an RRC message, a MAC-CE message, or a DCI. When the following information is sent to UE #0 via one or both of the RRC and MAC-CE messages received prior to step S1060, the instructions for performing steps S1071 and S1072 can be executed by the DCI.

[0234] In steps S1071 and S1072, UE #0 can send UL data to the corresponding UL-only TRP (i.e., UL-only TRP #1, ..., and UL-only TRP #M). Figure 10b In the example, it is assumed that the number of UL-only TRPs determined for UE #0 is two or more. However, the first TRP can determine only one UL-only TRP for a specific UE, or as... Figure 10b As shown, the first TRP can determine two or more UL-only TRPs for a UE.

[0235] Figure 12This is a conceptual diagram illustrating the situation where the UE transmits uplink signals via beam scanning in the third scenario of an asymmetric mTRP environment.

[0236] refer to Figure 12 Base station 1241 can communicate with UE 1211 in the cell located at base station 1241 using multiple TRPs 1201, 1202, and 1203. Figure 12 In the example, for the sake of simplicity, only three TRPs 1201, 1202, and 1203 are shown, but the number of TRPs that can be included in base station 1241 is not limited to three. That is, base station 1241 can include one TRP, two TRPs, or four or more TRPs. However, since this disclosure describes an mTRP environment, the case where base station 1241 includes only one TRP is not considered.

[0237] exist Figure 12 In an exemplary embodiment, it is assumed that a base station 1241 includes three different TRPs. The first TRP 1201 may have a first cell area 1110, the second TRP 1202 may have a second cell area 1220, and the third TRP 1203 may have a third cell area 1230. Figure 12 The first TRP 1201 shown can be referred to as a macro TRP or header TRP as described above, and the first TRP 1201 can perform DL and UL communication with UE 1211. Furthermore, the second TRP 1202 and the third TRP 1203 can be the UL-only TRPs described above. Therefore, the second TRP 1202 and the third TRP 1203 can be TRPs that do not transmit signals in the downlink, or they can be TRPs that transmit only minimal downlink signals.

[0238] Figure 12 The UE 1211 shown can correspond to Figure 10a and Figure 10b The UE is described as UE #0, and UE 1211 can be in an RRC connection state with the first TRP 1201. The first TRP 1201 can instruct UE 1211 to send an SRS or a preamble. Figure 12 As shown, UE 1211 can transmit SRS or preamble based on the number of UL signals per beam scan in each group indicated by the first TRP 1201 in the beam direction configurable by UE 1211 and the transmission timing of each group.

[0239] Figure 12 The example can correspond to the reference above. Figure 10b The described step S1040. (e.g.) Figure 12As shown, at least one UL-only TRP receiving the SRS or preamble transmitted by UE1211 can provide information about the received power to the first TRP 1201 and / or base station 1241. The first TRP 1201 and / or base station 1241 can determine a PL offset value to address the problem of excessive UL received power as described above. The determination of the PL offset value will be described in more detail below.

[0240] Here, when the first TRP 1201, the base station managing the first TRP 1241, and the network managing the base station ( Figure 12 When the carrier frequency used by UE 1211 is, for example, 6 GHz or higher FR2 (e.g., 24.25 to 52.6 GHz) and FR2-1 (e.g., 52.6 to 71 GHz), the aforementioned unknown UL TRP problem and UL OOS problem may occur simultaneously due to high path loss and the use of beamforming.

[0241] Furthermore, when the carrier frequency used by UE 1211 is, for example, 6 GHz or lower FR1 (e.g., 0.41 to 6 GHz), there may be cases where beamforming is not used. When beamforming is not used, the OOS-only problem of the two issues mentioned above may become critical. That is, depending on the type of UL signal that UE 1211 sends to the UL-only TRP in order to calculate the aforementioned PL offset value, it may experience all of the aforementioned problems or only one of the aforementioned problems.

[0242] When the first TRP 1201, the base station managing the first TRP 1241, and the network (NW) managing the base station (NW) Figure 12 When the carrier frequency used by UE 1211 is in the FR1 range (e.g., 0.41 to 6 GHz) or lower (not shown in the diagram), UE 1211 can transmit signals / channels by forming a quasi-omnidirectional beam pattern even if the location of the adjacent UL-only TRP is unknown. Therefore, the aforementioned unknown UL-only TRP problem may be mitigated to some extent. However, the aforementioned OOS problem may depend on what type of UL signal the UE transmits to the UL-only TRP in order to calculate the aforementioned PL offset value.

[0243] The process for determining the PL offset value and the operations up to the transmission of the SRS and / or preamble are described below, depending on whether the UL signal is an SRS or a PRACH preamble.

[0244] When the UE forms a quasi-omnidirectional transmission beam pattern in the FR1 band and / or a directional transmission beam pattern in the FR2 or FR2-1 band, it can be assumed that the type of UL signal transmitted by the UE is SRS. Then, through an exemplary embodiment described below, the UE can transmit SRS for at least one of CSI measurement, uplink beam management, PL offset determination, TT offset determination, TT offset estimation, or TT offset collection.

[0245] First, the first TRP, base station (gNB), or network (NW) (hereinafter referred to as 'NW') can send at least one of RRC signaling, MAC-CE, or DCI to the UE, and at least one of RRC signaling, MAC-CE, or DCI can include an SRS request field. DCI can instruct the UE to send SRS. As mentioned above, DCI can indicate SRS as quasi-omnidirectional or directional. Furthermore, SRS can be used for CSI measurement, uplink beam management, PL offset determination, TT offset determination, TT offset estimation, or TT offset collection.

[0246] Here, the SRS transmitted by the UE can correspond to an SRS resource set, and the SRS resource set can be transmitted using time resources and frequency resources indicated by a resource configuration. However, in this case, the OOS problem mentioned above may occur. Furthermore, to resolve the OOS problem, at least two SRS resource sets configured with different transmission timings can be transmitted using their respective indicated time and frequency resource sets. To resolve the aforementioned unknown UL TRP-only problem, one and / or two or more SRS resource sets can include SRS resources that perform beam scanning in multiple directions.

[0247] Additionally, for CSI measurements, uplink beam management, PL offset determination, TT offset determination, TT offset estimation, or TT offset collection, at least one of RRC signaling, MAC-CE, or DCI can be configured with fields such as PL offset determination indicator, transmit timing indicator, or transmit timing value (or index).

[0248] The PL offset determination indicator field can be configured to 1 bit. For example, when the bit information of the PL offset determination indicator field is set to '1', this bit information can instruct the RRC / MAC-CE / DCI to enable the first TRP, base station, or NW to determine the PL offset value of only the UL TRP.

[0249] The transmission timing indicator field can be configured to 1 bit. For example, when the bit information of the transmission timing indicator field is set to '0', this bit information can indicate that: in order for the NW to determine the PL offset value of the UL TRP only, the transmission timing of the SRS resource set transmitted by the UE follows the transmission timing used when transmitting signals / channels to the first TRP, which is the transmission timing at which... Figure 10a The configuration is as described in the section regarding the connection establishment between the first TRP and the UE. On the other hand, when the bit information of the transmission timing indicator field is set to '1', this bit information can indicate that the SRS resource set is transmitted using a transmission timing different from the transmission timing used when the UE transmits signals / channels to the first TRP. Here, the NW may not use the PL offset determination indicator field when the UE is identified as being able to identify the transmission timing indicator field used to determine the PL offset value of the UL-only TRP by using at least one of RRC signaling, MAC-CE, or DCI.

[0250] When the bit information of the transmit timing indicator field is set to '1', the transmit timing value (or index) field can be used. When the bit information of the transmit timing indicator field is set to '1', the transmit timing value (or index) field can indicate a transmit timing value (or index) other than the transmit timing used when transmitting a signal (or channel) to the first TRP. The transmit timing value (or index) field may not be used when the transmit timing indicator field value itself indicates a transmit timing value predefined in the technical specification.

[0251] For example, when using two transmit timings, the transmit timing can be determined as follows. The first transmit timing can be specified as... Figure 10a The second transmission timing, configured during connection establishment between the first TRP and the UE, refers to the transmission timing for sending signals (or channels) to the first TRP, and may refer to a transmission timing that is delayed by a TA offset compared to the transmission timing for sending signals to the first TRP. The reason for configuring the second transmission timing is to ensure that only the ULTRP, which is closer to the UE than the first TRP, can successfully receive (or estimate) the SRS resource set without OOS.

[0252] The reason for configuring the first transmission timing is to enable the UL-only TRPs located around the first TRP to successfully receive (or channel estimate) the SRS. The target UL-only TRPs used for configuring the first transmission timing can include: UL-only TRPs where a PL (e.g., 10 dB) greater than the PL between the UE and the first TRP is used to introduce the concept of UL off-loading. Furthermore, to introduce the concept of UL off-loading, UL-only TRPs where a PL greater than the PL between the UE and the first TRP is, for example, 60 dB, can also be target UL-only TRPs. To satisfy UL-only TRPs where a PL greater than 60 dB is used, the NW can configure a third transmission timing, i.e., an earlier transmission timing than the transmission timing used when the UE transmits a signal / channel to the first TRP.

[0253] Additionally, the NW can configure an SRS resource set for CSI measurement, uplink beam management, PL offset determination, TT offset determination, TT offset estimation, or TT offset collection via DCI, MAC-CE, or RRC signaling including an SRS request field, and can deliver this SRS resource set to the UE. The NW can instruct the UE of periodic SRS transmissions, and can instruct the UE of quasi-omnidirectional or directional SRS transmissions. As another example, the NW can instruct the UE of semi-persistent SRS transmissions, and can instruct the UE of quasi-omnidirectional or directional SRS transmissions. As yet another example, the NW can instruct the UE of aperiodic SRS transmissions, and can instruct the UE of quasi-omnidirectional or directional SRS transmissions. The related procedures will be described in more detail below.

[0254] In addition, the procedures for SRS resource activation, SRS resource modification, SRS resource reconfiguration, and SRS resource deactivation are described below.

[0255] First, for ease of understanding, the main functions of SRS are described for reference.

[0256] SRS can be used for CSI collection. The UE can send SRS to the network (e.g., the base station gNB) so that the network can accurately identify the UL channel state. The NW can use the SRS sent by the UE to perform important network operations such as beamforming, link adaptation, and resource allocation.

[0257] SRS can be used for frequency-selective scheduling. SRS can be transmitted on multiple frequency bands, and by transmitting SRS on multiple frequency bands, the network can assess the status of various frequency channels and select the best resources.

[0258] SRS can be used for uplink beam management. Combined with multi-antenna technology (i.e., multiple-input multiple-output (MIMO)), SRS can play an important role in determining the optimal beam direction in the uplink.

[0259] SRS can be used for uplink synchronization tracking and for determining asymmetric UL PL and TT offsets. Typically, the network can track and update uplink synchronization using SRS transmitted by the UE. Furthermore, in asymmetric mTRP scenarios with only UL TRP, the network can use SRS to determine the PL and TT offsets for uplink power control and uplink synchronization in UL TRP-only scenarios.

[0260] Next, the SRS-related RRC message correlation procedure performed by the NW is described. This procedure can be particularly useful when controlling periodic SRS transmissions.

[0261] (1) The network can send an RRC reconfiguration message or an RRC connection reconfiguration message to the UE. The UE can receive the RRC reconfiguration message or RRC connection reconfiguration message sent by the network, and can identify information such as the transmission time of the SRS, the frequency allocation of the SRS, the transmit power of the SRS, and the beamforming configuration from the SRS resource configuration (SRS-Config) information and the information in each SRS resource field. The RRC reconfiguration message or RRC connection reconfiguration message may include a list of SRS resources to be added or modified.

[0262] The SRS Resource Configuration (SRS-Config) Information Element (IE) in RRC signaling can be configured as follows. The RRC protocol can use the SRS-Config IE configured for the UE to send SRS. According to the current 5G NR specification, the SRS-Config IE can include the following main fields:

[0263] - The srs-ResourceSetToAddModList field: This field defines a set of groups for multiple SRS resources. A resource set can include multiple SRS resources and can be configured to transmit SRS at different frequency locations and times. The srs-ResourceSetToAddModList field can primarily be configured to enable the base station to receive SRS on specific time and frequency resources.

[0264] - The srs-ResourceSetToReleaseList field: The srs-ResourceSetToReleaseList field can be used to release previously configured SRS resources. The srs-ResourceSetToReleaseList field can be used during RRC reconfiguration and can be used to remove SRS resources that are no longer needed.

[0265] - The srs-ResourceToAddModList field: The srs-ResourceToAddModList field can be used to add new SRS resources or modify existing SRS resources. The srs-ResourceToAddModList field can be used when the base station configures new SRS resources to obtain additional channel information from the UE.

[0266] - aperiodicSRS-ResourceTrigger field: The aperiodicSRS-ResourceTrigger field can specify the code point of the DCI that triggers the SRS transmission based on the configured SRS resource set.

[0267] - srs-PowerControl field: The srs-PowerControl field may include an alpha field for power control of SRS transmission, and the alpha field can be used to adjust the UE's transmit power according to path loss.

[0268] - Transmission comb and frequency domain configuration fields: The transmission comb and frequency domain configuration fields can configure the frequency domain resource mapping, transmission comb, frequency hopping value, etc. of SRS.

[0269] - SlotOffset field: The SlotOffset field can specify the time offset between the triggered DCI and the actual SRS transmission in units of time slots.

[0270] - Resource type and periodicity fields: The resource type and periodicity fields define whether the SRS is periodic, aperiodic, or semi-persistent. The periodicity of the SRS transmission by the UE can be determined through the resource type and periodicity fields.

[0271] In this disclosure, to enable the UL TRP alone to estimate the receive power and receive timing error required by the base station to determine the PL offset and TT offset in an asymmetric uplink scenario without OOS, a SampleOffset field can be added to the SRS-Config IE defined in the current 5G NR specification. The SampleOffset field can specify the time offset from the first sample of the start symbol of the actual SRS transmission in samples. When the SampleOffset field is configured to 1 bit, a bit value '0' can indicate an SRS transmission at the uplink transmission timing configured for the first TRP, and a bit value '1' can indicate an SRS transmission at a timing that is delayed by a TA offset (e.g., SampleOffset) from the uplink transmission timing configured for the first TRP.

[0272] When the SampleOffset field is configured to 2 bits, bit information '00' can indicate SRS transmission at the uplink transmission timing configured for the first TRP, bit information '01' can indicate SRS transmission at a timing point delayed by TA offset 1 from the uplink transmission timing configured for the first TRP, bit information '10' can indicate SRS transmission at a timing point delayed or advanced by TA offset 2 from the uplink transmission timing configured for the first TRP, and bit information '11' can be reserved.

[0273] Each SRS resource can have a separate configuration field, which can include information about when, where, and how often the SRS is sent. The fields for each SRS resource might be as follows.

[0274] - srs-ResourceId field: The srs-ResourceId field indicates a unique identifier (ID) for the corresponding SRS resource. A specific resource among multiple SRS resources can be distinguished using the srs-ResourceId field.

[0275] - The nrofSRS-Ports field: The nrofSRS-Ports field defines the number of antenna ports used for SRS transmission. More specifically, the nrofSRS-Ports field can configure how many antenna ports are used in a multi-antenna or MIMO environment. For example, the nrofSRS-Ports field can have values ​​such as 1, 2, or 4, and such values ​​can be important parameters for multi-beamforming.

[0276] - The resourceType field: The resourceType field can be a field that defines the type of SRS resource and can be classified as periodic, semi-persistent, or aperiodic. When the resourceType field is configured as periodic, it can instruct the UE to transmit periodic SRS. When the resourceType field is configured as semi-persistent, it can instruct the UE to transmit SRS according to a pre-configured time interval. And when the resourceType field is configured as aperiodic, it can instruct the UE to send SRS aperiodically as needed.

[0277] - The transmissionComb field: The transmissionComb field determines the arrangement of SRS transmissions in the frequency domain. The transmissionComb field can be used in conjunction with combOffset and can define how SRS is transmitted across various frequency resources.

[0278] - cyclicShift field: The cyclicShift field indicates the cyclic shift value used to allow different SRS signals to share frequency resources. Using the cyclicShift field, multiple SRS signals can be transmitted efficiently without mutual interference.

[0279] - The frequencyPosition field: The frequencyPosition field can define the location of the frequency band for transmitting SRS. The frequencyPosition field can be used to allow the base station to collect channel state information on the desired frequency resources.

[0280] - frequencyShift field: The frequencyShift field defines the shift value in the frequency domain during SRS transmission. The frequencyShift field can be used to more efficiently distribute SRS signals within a specific frequency band.

[0281] - The frequencyHopping field: The frequencyHopping field configures whether frequency hopping is used during SRS transmission. Frequency hopping is a technique that increases transmission reliability by using various frequency resources.

[0282] - The groupOrSequenceHopping field: The groupOrSequenceHopping field can be used to change the transmission frequency of SRS by using group frequency hopping or sequence frequency hopping. The groupOrSequenceHopping field can be beneficial for reducing interference and ensuring frequency diversity.

[0283] - The resourceMapping field: The resourceMapping field defines the time and frequency resource mapping for SRS. The resourceMapping field can be configured with detailed parameters, such as symbol start, number of symbols (numSymbols), and number of subcarriers (numSubcarriers), and can determine which symbols and subcarriers to transmit SRS on.

[0284] - srs-ConfigIndex field: The srs-ConfigIndex field can be an index that defines the periodicity and transmission interval of the SRS. Based on the value of the srs-ConfigIndex field, the SRS can be sent periodically or non-periodically.

[0285] - srs-PeriodicityAndOffset field: The srs-PeriodicityAndOffset field defines the interval and start timing for periodic SRS transmissions. For example, the srs-PeriodicityAndOffset field can indicate SRS transmissions with periodicity such as 20 ms, 40 ms, or 80 ms.

[0286] - srs-TransmissionComb field: The srs-TransmissionComb field determines how SRS resources are transmitted in the frequency domain. For example, the srs-TransmissionComb field can be configured differently for frequency resources using combo0 or combo1.

[0287] - antennaPorts field: The antennaPorts field defines the antenna ports through which SRS is transmitted. The antennaPorts field is crucial in multi-antenna configurations for beamforming. When multi-antenna transmission is supported, SRS can be transmitted through multiple antenna ports, and the NW can measure the channel state on each beam through multiple antenna ports. The configuration of the antennaPorts field can vary depending on the use of FR1, FR2, or FR2-1. For example, when using FR1, the value of the antennaPorts field can be configured according to the quasi-omnidirectional beam pattern (e.g., configured as a single antenna port), and the OOS problem mentioned above can be addressed by configuring the SampleOffset field. As another example, when using FR2 or FR2-1, the value of the antennaPorts field can be configured according to the directional beam pattern (e.g., configured as multiple different antenna ports), and both the unknown UL-only TRP problem and the OOS problem mentioned above can be addressed by configuring the SampleOffset field.

[0288] - srs-PowerControl field: The srs-PowerControl field can be a power control configuration used during SRS transmission. The srs-PowerControl field can be used to adjust the appropriate transmit power to improve the quality of the signal received at the first TRP.

[0289] (2) The network can activate or modify SRS resources. More specifically, the network can trigger SRS transmission via RRC messages. When the SampleOffset field is not added to the RRC Reconfiguration or RRC Connection Reconfiguration message, the SampleOffset field needs to be added to the RRC message used to trigger SRS transmission. On the other hand, when the SampleOffset field is added to the RRC Reconfiguration or RRC Connection Reconfiguration message, the SampleOffset field can be added to the RRC message used to trigger SRS transmission, or it may not be added. The RRC message used to trigger SRS transmission can dynamically modify, add, or release SRS resources. Furthermore, the RRC message used to trigger SRS transmission can activate or deactivate SRS transmission according to network requirements. The RRC message used to trigger SRS transmission can specify a reference signal (e.g., CSI-RS or SSB), which the UE uses to estimate the path loss for power control of SRS transmission.

[0290] (3) The UE can adjust the SRS transmission power by referring to the path loss and can transmit SRS according to the time domain configuration (e.g., time slot offset and periodicity).

[0291] (4) The base station (gNB) can send another RRC reconfiguration message to the UE in order to reconfigure or deactivate the UE’s SRS resources as needed.

[0292] Next, the procedures related to MAC-CE messages associated with SRS, executed by the network, are described.

[0293] The procedure for instructing and terminating SRS transmissions via MAC-CE is an important mechanism for the network to dynamically request or terminate SRS transmissions from the UE. This procedure can be particularly useful when controlling semi-persistent SRS transmissions. MAC-CE can execute such instructions through efficient exchange of control messages between the network and the UE. The procedure for instructing and terminating SRS transmissions via MAC-CE is as follows.

[0294] MAC-CE is a control message used at the MAC layer, and it can deliver control commands such as SRS triggering. MAC-CE can be used to instruct or terminate an SRS transmission by the UE, and it can deliver the required control information with a very small message size. MAC-CE may include a trigger signal for SRS transmission, and the UE can receive the MAC-CE message and perform a semi-persistent SRS transmission in the resources configured by the MAC-CE message. The process of instructing an SRS transmission via MAC-CE is as follows.

[0295] (1) The network can send an RRC reconfiguration message or an RRC connection reconfiguration message to the UE. The UE can receive the RRC reconfiguration message or the RRC connection reconfiguration message sent by the network. The RRC reconfiguration message or the RRC connection reconfiguration message enables the identification of information such as transmission time, frequency allocation, transmit power, and beamforming configuration of the SRS from the SRS-Config IE and per SRS resource field information. The RRC reconfiguration message or the RRC connection reconfiguration message may include a list of SRS resources to be added or modified. The RRC protocol can use a message element called the SRS-Config IE, which configures the UE to transmit SRS, and according to the current 5G NR specification, the main fields of the SRS resource configuration (SRS-Config) IE in the RRC are as follows.

[0296] - The srs-ResourceSetToAddModList field: This field defines a set of groups for multiple SRS resources. A resource set can include multiple SRS resources and can be configured to transmit SRS at different frequency locations and times. The srs-ResourceSetToAddModList field can primarily be configured to enable the base station to receive SRS on specific time and frequency resources.

[0297] - The srs-ResourceSetToReleaseList field: The srs-ResourceSetToReleaseList field can be used to release previously configured SRS resources. The srs-ResourceSetToReleaseList field can be used during RRC reconfiguration and can be used to remove SRS resources that are no longer needed.

[0298] - The srs-ResourceToAddModList field: The srs-ResourceToAddModList field can be used to add new SRS resources or modify existing SRS resources. The srs-ResourceToAddModList field can be used when the base station configures new SRS resources to obtain additional channel information from the UE.

[0299] - aperiodicSRS-ResourceTrigger field: The aperiodicSRS-ResourceTrigger field can specify the code point of the DCI that triggers the SRS transmission based on the configured SRS resource set.

[0300] - srs-PowerControl field: The srs-PowerControl field may include an alpha field for power control of SRS transmission, and the alpha field can be used to adjust the UE's transmit power according to path loss.

[0301] - Transmission comb and frequency domain configuration fields: The transmission comb and frequency domain configuration fields can configure the frequency domain resource mapping, transmission comb, frequency hopping value, etc. of SRS.

[0302] - SlotOffset field: The SlotOffset field can specify the time offset between the triggered DCI and the actual SRS transmission in units of time slots.

[0303] - Resource type and periodicity fields: The resource type and periodicity fields define whether the SRS is periodic, aperiodic, or semi-persistent. The periodicity of the SRS transmission by the UE can be determined through the resource type and periodicity fields.

[0304] In this disclosure, to enable UL TRP alone to estimate the receive power and receive timing error required by the base station to determine the PL offset and TT offset in an asymmetric uplink scenario without OOS, a SampleOffset field can be added to the SRS-Config IE defined in the current 5G NR specification. The SampleOffset field can specify the time offset from the first sample of the start symbol of the actual SRS transmission in units of samples.

[0305] Each SRS resource can have a separate configuration field, which can include information about when, where, and how often the SRS is sent. The fields for each SRS resource might be as follows.

[0306] - srs-ResourceId field: The srs-ResourceId field indicates the unique ID of the corresponding SRS resource. The srs-ResourceId field can be used to distinguish a specific resource among multiple SRS resources.

[0307] - The nrofSRS-Ports field: The nrofSRS-Ports field defines the number of antenna ports used for SRS transmission. More specifically, the nrofSRS-Ports field can configure how many antenna ports are used in a multi-antenna or MIMO environment. For example, the nrofSRS-Ports field can have values ​​such as 1, 2, or 4, and such values ​​can be important parameters for multi-beamforming.

[0308] - The resourceType field: The resourceType field can be a field that defines the type of SRS resource and can be classified as periodic, semi-persistent, or aperiodic. When the resourceType field is configured as periodic, it can instruct the UE to transmit periodic SRS. When the resourceType field is configured as semi-persistent, it can instruct the UE to transmit SRS according to a pre-configured time interval. And when the resourceType field is configured as aperiodic, it can instruct the UE to send SRS aperiodically as needed.

[0309] - The transmissionComb field: The transmissionComb field determines the arrangement of SRS transmissions in the frequency domain. The transmissionComb field can be used in conjunction with combOffset and can define how SRS is transmitted across various frequency resources.

[0310] - cyclicShift field: The cyclicShift field indicates the cyclic shift value used to allow different SRS signals to share frequency resources. Using the cyclicShift field, multiple SRS signals can be transmitted efficiently without mutual interference.

[0311] - The frequencyPosition field: The frequencyPosition field can define the location of the frequency band for transmitting SRS. The frequencyPosition field can be used to allow the base station to collect channel state information on the desired frequency resources.

[0312] - frequencyShift field: The frequencyShift field defines the shift value in the frequency domain during SRS transmission. The frequencyShift field can be used to more efficiently distribute SRS signals within a specific frequency band.

[0313] - The frequencyHopping field: The frequencyHopping field configures whether frequency hopping is used during SRS transmission. Frequency hopping is a technique that increases transmission reliability by using various frequency resources.

[0314] - The groupOrSequenceHopping field: The groupOrSequenceHopping field can be used to change the transmission frequency of SRS by using group frequency hopping or sequence frequency hopping. The groupOrSequenceHopping field can be beneficial for reducing interference and ensuring frequency diversity.

[0315] - The resourceMapping field: The resourceMapping field defines the time and frequency resource mapping for SRS. The resourceMapping field can be configured with detailed parameters, such as symbol start, number of symbols (numSymbols), and number of subcarriers (numSubcarriers), and can determine which symbols and subcarriers to transmit SRS on.

[0316] - srs-ConfigIndex field: The srs-ConfigIndex field can be an index that defines the periodicity and transmission interval of the SRS. Based on the value of the srs-ConfigIndex field, the SRS can be sent periodically or non-periodically.

[0317] - srs-PeriodicityAndOffset field: The srs-PeriodicityAndOffset field defines the interval and start timing for periodic SRS transmissions. For example, the srs-PeriodicityAndOffset field can indicate SRS transmissions with periodicity such as 20 ms, 40 ms, or 80 ms.

[0318] - srs-TransmissionComb field: The srs-TransmissionComb field determines how SRS resources are transmitted in the frequency domain. For example, the srs-TransmissionComb field can be configured differently for frequency resources via combo0 or combo1.

[0319] - antennaPorts field: The antennaPorts field defines the antenna port number through which SRS is transmitted. The antennaPorts field is crucial in multi-antenna configurations used for beamforming. When multi-antenna transmission is supported, SRS can be transmitted through multiple antenna ports, and the NW can measure the channel state on each beam through multiple antenna ports. The configuration of the antennaPorts field can vary depending on the use of FR1, FR2, or FR2-1. For example, when using FR1, the value of the antennaPorts field can be configured according to the quasi-omnidirectional beam pattern (e.g., configured as a single antenna port), and the OOS problem mentioned above can be addressed by configuring the SampleOffset field. As another example, when using FR2 or FR2-1, the value of the antennaPorts field can be configured according to the directional beam pattern (e.g., configured as multiple different antenna ports), and both the unknown UL-only TRP problem and the OOS problem mentioned above can be addressed by configuring the SampleOffset field.

[0320] - srs-PowerControl field: The srs-PowerControl field can be a power control configuration used during SRS transmission. The srs-PowerControl field can be used to adjust the appropriate transmit power to improve the quality of the signal received at the first TRP.

[0321] (2) During semi-persistent SRS transmission, the network can trigger an active SRS transmission to the UE using a MAC-CE message. In other words, the network can instruct the UE to send SRS using specific SRS resources via MAC-CE. The MAC-CE message can be sent together with the PUSCH transmission or sent independently. Fields in the MAC-CE message used for SRS triggering or activation may include SRS resource ID, trigger timing, transmission frequency range, etc. Here, in order to estimate the received power and received timing error required by the base station to determine the PL offset and TT offset in an asymmetric uplink scenario without OOS and unknown UL TRP issues, this disclosure may add new fields.

[0322] In this disclosure, in accordance with current 5G NR specifications, the SampleOffset field can be added to the MAC-CE for SRS triggering or SRS activation. The SampleOffset field can specify the time offset from the first sample of the start symbol of the actual SRS transmission, on a sample-by-sample basis.

[0323] When the SampleOffset field is configured to 1 bit, bit value '0' can indicate an SRS transmission at the uplink transmission timing configured for the first TRP, and bit value '1' can indicate an SRS transmission at a timing that is delayed by a TA offset (e.g., SampleOffset) from the uplink transmission timing configured for the first TRP.

[0324] When the SampleOffset field is configured with 2 bits, bit '00' can indicate an SRS transmission at the uplink transmission timing configured for the first TRP, bit '01' can indicate an SRS transmission at a timing point delayed by TA offset 1 from the uplink transmission timing configured for the first TRP, bit '10' can indicate an SRS transmission at a timing point delayed or advanced by TA offset 2 from the uplink transmission timing configured for the first TRP, and bit '11' can be reserved. When the SampleOffset field is not added to the aforementioned RRC Reconfiguration or RRC Connection Reconfiguration message, the SampleOffset field may need to be added to the MAC-CE according to this disclosure. On the other hand, when the SampleOffset field is added to the RRC Reconfiguration or RRC Connection Reconfiguration message, the MAC-CE according to this disclosure may further include the SampleOffset field, or may not further include the SampleOffset field.

[0325] (3) The SRS transmission process based on MAC-CE is as follows. The UE can transmit SRS in the specified resources according to the triggering information delivered by MAC-CE. SRS can be transmitted by utilizing the given frequency resources and time resources as indicated by MAC-CE. The network can receive the SRS transmitted by the UE. The network can use the received SRS to measure the uplink channel state. The network can use the uplink channel state measurement for resource scheduling and beamforming, or it can use the uplink channel state measurement to estimate the PL offset and TT offset.

[0326] When multi-antenna transmission is supported, SRS can be transmitted through multiple antenna ports, and the network can receive SRS transmitted through multiple antenna ports to measure the channel state of various beams. Here, in the trigger information delivered by MAC-CE, the SampleOffset field and the SRS transmission through multiple antenna ports (i.e., beam scanning transmission) can resolve the unknown UL-only TRP problem in beamforming modes.

[0327] (4) The SRS transmission termination process via MAC-CE is as follows. First, the network can issue an instruction to terminate the SRS transmission. When SRS transmission is no longer needed, the network can instruct the UE to stop (deactivate) the SRS transmission by using a MAC-CE message. In other words, the MAC-CE message can deliver a command to terminate the SRS transmission, and the UE can stop the SRS transmission immediately after receiving the MAC-CE message. For example, the fields of the SRS deactivation MAC-CE message may include the SRS resource ID, trigger timing, and transmission frequency range. Here, the SRS deactivation MAC-CE may include the SampleOffset field mentioned above.

[0328] (5) The RRC reconfiguration and transmission termination process is as follows. When the network needs to permanently stop SRS transmission or change the SRS configuration, the network can send a new SRS configuration to the UE through the RRC Connection Reconfiguration message and / or the SRS trigger (or activate) MAC-CE message. Through the RRC Connection Reconfiguration message and / or the SRS trigger MAC-CE message, the network can instruct the termination of the UE's SRS transmission periodicity, release the UE's SRS transmission resources, or deactivate the SRS transmission itself. When SRS transmission is terminated or when a new configuration is required, the network can deliver the new configuration to the UE through the RRC message and / or the SRS trigger or activate MAC-CE message. In this case, the UE can stop SRS transmission or start SRS transmission anew according to the new configuration.

[0329] Next, the DCI message-related procedures for SRS executed by the network are described. SRS requests via DCI can primarily be used to trigger aperiodic SRS transmissions. This allows the network to assess the uplink channel status in real time. The processes from SRS resource allocation to SRS transmission and SRS resource reallocation are described below.

[0330] (1) The network can send an RRC reconfiguration message or an RRC connection reconfiguration message to the UE. The UE can identify information about the SRS transmission time, frequency allocation, transmit power, and beamforming configuration of SRS transmission from the SRS-Config IE and per SRS resource field information included in the RRC reconfiguration message or RRC connection reconfiguration message received from the network. The RRC reconfiguration message or RRC connection reconfiguration message may include a list of SRS resources to be added or modified. The RRC protocol can use the SRS-Config IE, which configures the UE to configure the transmission of SRS, and according to the current 5G NR specification, the main fields included in the SRS-Config IE are as follows.

[0331] - The srs-ResourceSetToAddModList field: This field defines a set of groups for multiple SRS resources. A resource set can include multiple SRS resources and can be configured to transmit SRS at different frequency locations and times. The srs-ResourceSetToAddModList field can primarily be configured to enable the base station to receive SRS on specific time and frequency resources.

[0332] - The srs-ResourceSetToReleaseList field: The srs-ResourceSetToReleaseList field can be used to release previously configured SRS resources. The srs-ResourceSetToReleaseList field can be used during RRC reconfiguration and can be used to remove SRS resources that are no longer needed.

[0333] - The srs-ResourceToAddModList field: The srs-ResourceToAddModList field can be used to add new SRS resources or modify existing SRS resources. The srs-ResourceToAddModList field can be used when the base station configures new SRS resources to obtain additional channel information from the UE.

[0334] - aperiodicSRS-ResourceTrigger field: The aperiodicSRS-ResourceTrigger field can specify the code point of the DCI that triggers the SRS transmission based on the configured SRS resource set.

[0335] - srs-PowerControl field: The srs-PowerControl field may include an alpha field for power control of SRS transmission, and the alpha field can be used to adjust the UE's transmit power according to path loss.

[0336] - Transmission comb and frequency domain configuration fields: The transmission comb and frequency domain configuration fields can configure the frequency domain resource mapping, transmission comb, frequency hopping value, etc. of SRS.

[0337] - SlotOffset field: The SlotOffset field can specify the time offset between the triggered DCI and the actual SRS transmission in units of time slots.

[0338] - Resource type and periodicity fields: The resource type and periodicity fields define whether the SRS is periodic, aperiodic, or semi-persistent. The periodicity of the SRS transmission by the UE can be determined through the resource type and periodicity fields.

[0339] In this disclosure, to enable UL TRP alone to estimate the receive power and receive timing errors required by the base station to determine PL offset and TT offset in an asymmetric uplink scenario without OOS, a SampleOffset field can be added to the SRS-Config IE defined in the current 5G NR specification. The SampleOffset field can specify the time offset from the first sample of the start symbol of the actual SRS transmission in units of samples.

[0340] Each SRS resource can have a separate configuration field, which can include information about when, where, and how often the SRS is sent. The fields for each SRS resource might be as follows.

[0341] - srs-ResourceId field: The srs-ResourceId field indicates the unique ID of the corresponding SRS resource. The srs-ResourceId field can be used to distinguish a specific resource among multiple SRS resources.

[0342] - The nrofSRS-Ports field: The nrofSRS-Ports field defines the number of antenna ports used for SRS transmission. More specifically, the nrofSRS-Ports field can configure how many antenna ports are used in a multi-antenna or MIMO environment. For example, the nrofSRS-Ports field can have values ​​such as 1, 2, or 4, and such values ​​can be important parameters for multi-beamforming.

[0343] - The resourceType field: The resourceType field can be a field that defines the type of SRS resource and can be classified as periodic, semi-persistent, or aperiodic. When the resourceType field is configured as periodic, it can instruct the UE to transmit periodic SRS. When the resourceType field is configured as semi-persistent, it can instruct the UE to transmit SRS according to a pre-configured time interval. And when the resourceType field is configured as aperiodic, it can instruct the UE to send SRS aperiodically as needed.

[0344] - The transmissionComb field: The transmissionComb field determines the arrangement of SRS transmissions in the frequency domain. The transmissionComb field can be used in conjunction with combOffset and can define how SRS is transmitted across various frequency resources.

[0345] - cyclicShift field: The cyclicShift field indicates the cyclic shift value used to allow different SRS signals to share frequency resources. Using the cyclicShift field, multiple SRS signals can be transmitted efficiently without mutual interference.

[0346] - The frequencyPosition field: The frequencyPosition field can define the location of the frequency band for transmitting SRS. The frequencyPosition field can be used to allow the base station to collect channel state information on the desired frequency resources.

[0347] - frequencyShift field: The frequencyShift field defines the shift value in the frequency domain during SRS transmission. The frequencyShift field can be used to more efficiently distribute SRS signals within a specific frequency band.

[0348] - The frequencyHopping field: The frequencyHopping field configures whether frequency hopping is used during SRS transmission. Frequency hopping is a technique that increases transmission reliability by using various frequency resources.

[0349] - The groupOrSequenceHopping field: The groupOrSequenceHopping field can be used to change the transmission frequency of SRS by using group frequency hopping or sequence frequency hopping. The groupOrSequenceHopping field can be beneficial for reducing interference and ensuring frequency diversity.

[0350] - The resourceMapping field: The resourceMapping field defines the time and frequency resource mapping for SRS. The resourceMapping field can be configured with detailed parameters, such as symbol start, number of symbols (numSymbols), and number of subcarriers (numSubcarriers), and can determine which symbols and subcarriers to transmit SRS on.

[0351] - srs-ConfigIndex field: The srs-ConfigIndex field can be an index that defines the periodicity and transmission interval of the SRS. Based on the value of the srs-ConfigIndex field, the SRS can be sent periodically or non-periodically.

[0352] - srs-PeriodicityAndOffset field: The srs-PeriodicityAndOffset field defines the interval and start timing for periodic SRS transmissions. For example, the srs-PeriodicityAndOffset field can indicate SRS transmissions with periodicity such as 20 ms, 40 ms, or 80 ms.

[0353] - srs-TransmissionComb field: The srs-TransmissionComb field determines how SRS resources are transmitted in the frequency domain. For example, the srs-TransmissionComb field can be configured differently for frequency resources via combo0 or combo1.

[0354] - antennaPorts field: The antennaPorts field defines the antenna port number through which SRS is transmitted. The antennaPorts field is crucial in multi-antenna configurations used for beamforming. When multi-antenna transmission is supported, SRS can be transmitted through multiple antenna ports, and the NW can measure the channel state on each beam through multiple antenna ports. The configuration of the antennaPorts field can vary depending on the use of FR1, FR2, or FR2-1. For example, when using FR1, the value of the antennaPorts field can be configured according to the quasi-omnidirectional beam pattern (e.g., configured as a single antenna port), and the OOS problem mentioned above can be addressed by configuring the SampleOffset field. As another example, when using FR2 or FR2-1, the value of the antennaPorts field can be configured according to the directional beam pattern (e.g., configured as multiple different antenna ports), and both the unknown UL-only TRP problem and the OOS problem mentioned above can be addressed by configuring the SampleOffset field.

[0355] - srs-PowerControl field: The srs-PowerControl field can be a power control configuration used during SRS transmission. The srs-PowerControl field can be used to adjust the appropriate transmit power to improve the quality of the signal received at the first TRP.

[0356] (2) DCI can trigger an SRS request. To trigger an aperiodic SRS transmission, the network can use the SRS request field in the DCI message. The DCI is sent to the UE via the PDCCH, and for example, an SRS request can be triggered by using the SRS request field included in one of DCI formats 0_1, 0_2, or 1_1. The SRS request field included in one of DCI formats 0_1, 0_2, or 1_1 can be configured to be 2 bits, and the network can request SRS from the UE using the SRS request field included in one of DCI formats 0_1, 0_2, or 1_1. The value of the SRS request field can indicate whether an SRS transmission is requested, or it can include information related to SRS. More specifically, the value of the SRS request field can be set as follows.

[0357] For example, a value of '00' in the SRS request field can indicate that an aperiodic SRS resource set has not been triggered, a value of '01' in the SRS request field can indicate an SRS resource set configured with the high-level parameter aperiodicSRS-ResourceTrigger set to 1, a value of '10' in the SRS request field can indicate an SRS resource set configured with the high-level parameter aperiodicSRS-ResourceTrigger set to 2, and a value of '11' in the SRS request field can indicate an SRS resource set configured with the high-level parameter aperiodicSRS-ResourceTrigger set to 3.

[0358] According to this disclosure, in order to estimate the received power and received timing error required by the base station gNB to determine the PL offset, TT offset, etc., between only the UL TRP and the UE in an asymmetric uplink scenario without OOS, a SampleOffset field can be added to the DCI format used for SRS triggering. The SampleOffset field can specify the time offset from the first sample of the start symbol of the actual SRS transmission in units of samples, and can be configured to 1 bit or 2 bits.

[0359] When the SampleOffset field is configured to 1 bit, bit '0' can indicate an SRS transmission at the uplink transmission timing configured for the first TRP, and bit '1' can indicate an SRS transmission at a timing that is delayed by a TA offset (e.g., SampleOffset) from the uplink transmission timing configured for the first TRP.

[0360] When the SampleOffset field is configured with 2 bits, bit information '00' can indicate SRS transmission at the uplink transmission timing configured for the first TRP, bit information '01' can indicate SRS transmission at a timing point delayed by TA offset 1 from the uplink transmission timing configured for the first TRP, bit information '10' can indicate SRS transmission at a timing point delayed or advanced by TA offset 2 from the uplink transmission timing configured for the first TRP, and bit information '11' can be reserved.

[0361] When the SampleOffset field is not added to the aforementioned RRC Reconfiguration and / or RRC Connection Reconfiguration messages, it may be added to the DCI used to trigger SRS transmission as illustrated above. Conversely, when the SampleOffset field is added to the RRC Reconfiguration and / or RRC Connection Reconfiguration messages, it may or may not be added to the DCI used to trigger SRS transmission as illustrated above.

[0362] (3) The SRS sending process can be performed as follows.

[0363] The UE can transmit SRS at a time delay (or advance) by the TA offset from the first sample of the first symbol of the time slot indicated in the aforementioned DCI message. SRS can be transmitted within allocated frequency resources, which can be configured within the subcarrier range used by the UE in the uplink. The network can control the transmit power used for SRS transmission. Furthermore, power control commands can be delivered via the aforementioned DCI.

[0364] (4) The SRS receive and uplink channel state assessment can be performed as follows.

[0365] The network can receive SRS transmitted by the UE and can evaluate the uplink channel state based on the received SRS. The SRS can be used to evaluate the uplink channel state in the frequency domain. The network can analyze the received SRS to evaluate the channel quality in each subcarrier and can reflect the evaluated channel quality in resource scheduling and beamforming.

[0366] (5) Feedback and resource reallocation can be performed as follows.

[0367] When assessing the uplink channel state based on SRS, the network can take the following actions: Based on the SRS received from the UE, the network can optimize uplink resource allocation. Furthermore, the network can change the modulation scheme or resource allocation based on the uplink channel state. If necessary, the network can indicate additional resource allocation information or transmission parameter changes to the UE via a new DCI message.

[0368] In the FR2 or FR2-1 frequency band, the UE can form a directional transmission beam pattern. When the UE forms a directional transmission beam pattern and assumes that the UL signal transmitted by the UE is an SRS, the UE can transmit SRS for CSI measurement, uplink beam management, PL offset and / or TT offset determination, PL offset and / or TT offset estimation, and PL offset and / or TT offset collection through the exemplary embodiments described below.

[0369] First, the first TRP (e.g., a macro TRP), base station (gNB), or network (NW) can instruct the UE to send SRS in a directed manner for CSI measurement, uplink beam management, PL offset and / or TT offset determination, PL offset and / or TT offset estimation, and PL offset and / or TT offset collection by using one or more of DCI, MAC-CE, or RRC signaling with an SRS request field. However, when the UE sends SRS to an uplink-only TRP according to instructions from the network (e.g., a macro TRP, base station, or network), the aforementioned unknown uplink-only TRP problem and OOS problem may occur simultaneously.

[0370] In addition, fields such as PL offset determination indicator, beam scan indicator, transmit timing indicator, transmit timing (or index) and / or SRS resource configuration can be configured in one or more of the RRC or MAC-CE messages used for CSI measurement, uplink beam management, PL offset and / or TT offset determination, PL offset and / or TT offset estimation, and PL offset and / or TT offset collection.

[0371] For example, RRC and / or MAC-CE messages can be configured to include one or more fields such as PL offset determination indicator, beam scan indicator, transmit timing offset value (or index), SRS resource configuration, and / or combined / UL TCI status.

[0372] The PL Offset Determination Indicator field can be configured to 1 bit. When the bit information of the PL Offset Determination Indicator field is set to '1', the PL Offset Determination Indicator field can indicate whether the RRC and / or MAC-CE message is used by the network (e.g., the first TRP (e.g., macro TRP), base station (gNB), or network) to determine the PL offset value of only the UL TRP. The PL Offset Determination Indicator field can be omitted because the beam scan indicator field following the PL Offset Determination Indicator field performs this function instead.

[0373] The beam scan indicator field can be configured to 1 bit for PL offset determination and for resolving unknown UL-only TRP issues via RRC and / or MAC-CE messages. When the beam scan indicator field is set to '1', it instructs the UE to execute an SRS transmission command using beamforming. Conversely, when the beam scan indicator field is set to '0', it instructs the UE to transmit SRS without beam scanning.

[0374] In the transmission timing value field (or transmission timing index field), the transmission timing offset value and the index indicating the transmission timing offset value can indicate an offset value (or offset index) relative to the transmission timing toward the first TRP configured during the connection process between the UE and the first TRP (e.g., macro TRP). For example, when the transmission timing offset value is 0, the transmission timing offset value can indicate the transmission timing value toward the first TRP (e.g., macro TRP). When the transmission timing offset value is positive, a positive transmission timing offset value can indicate that the SRS instruction is transmitted at a time earlier than the transmission timing toward the first TRP by a positive offset value. When the transmission timing offset value is negative, a negative transmission timing offset value can indicate that the SRS instruction is transmitted at a time later than the transmission timing toward the first TRP by a negative offset value.

[0375] SRS resource configuration can indicate the SRS resources sent to UL TRP only and / or the configuration used for SRS sequence generation.

[0376] For example, SRS resource configuration can be used to determine the PL offset based on information from the PL offset determination indicator field. However, when the indication is not to perform beam scanning and the transmission timing offset value is 0, SRS resource configuration can indicate the configuration used to generate the SRS sequence and SRS time / frequency resource information to be applied.

[0377] As another example, SRS resource configuration can be used to determine the PL offset based on information from the PL offset determination indicator field. When performing beam scanning and determining different transmit timing offset values, SRS resource configuration can instruct the configuration for generating the SRS sequence to be applied for each transmit timing and the SRS time / frequency resource information for beam scanning SRS.

[0378] As another example, the SRS resource configuration can determine the PL offset without relying on information from the PL offset determination indicator field. The SRS resource configuration can indicate the configuration used to generate the SRS sequence to be applied for each transmission timing and the SRS time / frequency resource information for beam scanning SRS when beam scanning is not performed and the transmit timing offset value is 0.

[0379] The combined / UL TCI status field can indicate the direction of the transmit beam of the UE for the SRS to be transmitted.

[0380] For example, the Joint / UL TCI Status field can be used to determine the PL offset based on the information in the aforementioned field. However, when beamforming is not performed and the transmission timing offset value is 0, the Joint / UL TCI Status field can indicate the UL transmit beam direction used to transmit the SRS with SRS resources configured by the aforementioned field.

[0381] As another example, the Joint / UL TCI Status field may not be used to determine the PL offset based on the information in the aforementioned fields. When beamforming is not performed and the transmission timing offset value is 0, the Joint / UL TCI Status field may indicate the UL transmit beam direction used to transmit the SRS with SRS resources configured by the aforementioned fields.

[0382] Additionally, if the UE can form a quasi-omnidirectional transmission beam pattern in the FR1 band, and assuming that the type of UL signal to be transmitted is a PRACH preamble, the UE can transmit a preamble for TA or PL offset determination, TT offset determination, TT offset estimation, and TT offset collection through the process described below.

[0383] First, the network (e.g., the first TRP (e.g., macro TRP), the base station, or the network) can instruct the UE to transmit predefined preambles for TA or PL offset determination, TT offset determination, TT offset estimation, and TT offset collection in a quasi-omnidirectional manner using one or more of the DCI, MAC-CE, or RRC signaling used for PDCCH commands. In this case, both the aforementioned unknown UL-only TRP problem and the OOS problem can be resolved.

[0384] One or more fields for TA or PL offset determination, TT offset determination, TT offset estimation, and TT offset collection in DCI, MAC-CE, or RRC signaling for PDCCH commands can be configured as follows.

[0385] (1) RRC and / or MAC-CE messages may include message fields such as PL offset determination indicator, random access preamble index and random access timing (RO).

[0386] For example, the PL Offset Determination Indicator field can be configured to 1 bit. When the bit information of the PL Offset Determination Indicator field is set to '1', the RRC and / or MAC-CE messages can indicate that the RRC and / or MAC-CE messages are used by the network to determine the PL offset value for ULTRP only. The Random Access Preamble Index field can indicate the index of the preamble to be sent in a quasi-omnidirectional manner to ULTRP only, and the RO field can indicate information about the time / frequency resource location for which the preamble is to be sent. The time / frequency resource of the RO can be determined by the network as a single RO time / frequency resource, or it can be any of the time / frequency resource locations for the RO cases defined in the current 5G NR specification, in which case the UE can ignore the SSB. When any of the time / frequency resources for the RO cases defined in the current 5G NR specification are indicated, the UE can randomly select a time / frequency resource location from all the time / frequency resources for the RO cases defined in the current 5G NR specification and send the preamble using the selected time / frequency resource.

[0387] (2) In the case of DCI used for PDCCH commands, the DCI 1_0 format for PDCCH command purposes can be configured with message fields such as a PL offset determination indicator in addition to the existing fields. Here, the PL offset determination indicator field (or asymmetric indicator field) can be configured to 1 bit. When the bit information of the PL offset determination indicator field is set to '1', the DCI can indicate that the DCI is for the network to determine the PL offset value for UL TRP only. When the bit information of the PL offset determination indicator field is set to '0', in the current 5G NR specification, the DCI can follow the DCI format of PDCCH commands. Here, it is possible to configure without adding the PL offset determination indicator field. In other words, since the UE sends a preamble according to the instruction of the received DCI for PDCCH commands even if it does not know whether the DCI is for PL offset determination, there may be no problem in the operation of the network determining the PL offset value by using the preamble sent from the UE.

[0388] Furthermore, when the bit information of the Asym indicator field is set to '1', the UL / SUL (Supplementary Uplink) indicator and / or SS / PBCH index of the current 5G NR specification become invalid. Therefore, the UL / SUL indicator field and / or SS / PBCH index field can be multiplexed for transmissions toward UL-only TRPs. As an example of multiplexing, PL offset index (and / or transmit power value / index) information for determining the transmit power of the preamble transmission via DCI can be configured in the UL / SUL indicator field and / or SS / PBCH index field.

[0389] In addition, when the UE can form a directional transmission beam pattern in the FR2 or FR2-1 band, and assuming that the type of UL signal to be transmitted by the UE is a preamble, the UE can transmit the preamble through the following process for TA or PL offset determination, TT offset determination, TT offset estimation and TT offset collection.

[0390] First, the network (e.g., the first TRP (e.g., macro TRP), the base station (gNB), or the network itself) can instruct the UE to send preambles for TA or PL offset determination, TT offset determination, TT offset estimation, and TT offset collection in a directed manner using DCI, MAC-CE, or RRC signaling for PDCCH commands. However, the aforementioned OOS problem can be resolved when the UE sends preambles to the UL-only TRP according to the network's instructions, but unknown UL-only TRP problems may arise.

[0391] One or more messages in the DCI, MAC-CE, or RRC signaling used for PDCCH commands for TA or PL offset determination, TT offset determination, TT offset estimation, and TT offset collection may have the following fields.

[0392] (1) In the case of RRC and / or MAC-CE messages, the RRC and / or MAC-CE messages may be configured with message fields such as PL offset determination indicator, beam scan indicator, random access preamble index and / or PRACH preamble resource configuration.

[0393] The PL Offset Determination Indicator field can be configured to 1 bit. When the bit information of the PL Offset Determination Indicator field is set to '1', the RRC and / or MAC-CE messages can indicate that the RRC and / or MAC-CE messages are used by the network to determine the PL offset value for ULTRP only. The PL Offset Determination Indicator field can be omitted because the beam scan indicator field that follows the PL Offset Determination Indicator field can serve the same function as the PL Offset Determination Indicator field.

[0394] The beam scan indicator field can be configured to 1 bit, for example, for PL offset determination and for resolving unknown UL-only TRP issues via RRC and / or MAC-CE messages. When the bit information of the beam scan indicator field is set to '1', the beam scan indicator field can instruct the UE to send a preamble using beam scanning. When the bit information of the beam scan indicator field is set to '0', the beam scan indicator field can instruct the UE to send a preamble without beam scanning.

[0395] The random access preamble index field indicates the index of the preamble to be generated and sent.

[0396] The PRACH preamble resource configuration field can indicate information about the location of time / frequency resources for transmitting the preamble. The time / frequency resources in the preamble resource configuration can indicate all time or frequency resources for which beam scanning is performed when beam scanning is indicated by information in one of the aforementioned fields (e.g., the beam scan indicator field). Conversely, when beam scanning is not performed as indicated by information in one of the aforementioned fields (e.g., the beam scan indicator field), the time / frequency resources in the preamble resource configuration can indicate the configuration of one or more time or frequency resources for which beam scanning is not performed.

[0397] (2) In the case of DCI for PDCCH commands, the DCI 1_0 format for PDCCH commands can be configured to include, in addition to the existing fields, PL offset determination indicator (or asymmetric indicator) and / or beam scan indicator fields.

[0398] The PL Offset Determination Indicator field can be configured to 1 bit. When the bit information of the PL Offset Determination Indicator field is set to '1', the DCI can indicate that the DCI is used by the network to determine the PL offset value for UL TRP only. In this case, the PL Offset Determination Indicator field can be omitted because the beam scan indicator field following the PL Offset Determination Indicator field can serve the same function as the PL Offset Determination Indicator field. Furthermore, when the PL Offset Determination Indicator field is additionally configured and its bit information is set to '1', the UL / SUL indicator, SS / PBCH index, or PRACH mask index in the current 5G NR specification becomes invalid, so this field can be multiplexed for transmissions toward UL TRP only.

[0399] For example, the UL / SUL indicator can be multiplexed as a beam scan indicator as described below. More specifically, when the bit information of the UL / SUL indicator is set to '1', the UL / SUL indicator can instruct the UE to perform a beam scan, and when the bit information of the UL / SUL indicator is set to '0', the UL / SUL indicator can instruct the UE not to perform a beam scan.

[0400] Furthermore, the SS / PBCH index and PRACH mask index can be reused as fields for allocating time / frequency resources for the beam direction of the preamble and / or the transmit power of the preamble to be transmitted based on whether beam scanning is performed. For example, when the bit information of the PL offset determination indicator is set to '1' and the bit value of the UL / SUL indicator is set to '1', the network can allocate time / frequency resources and / or transmit power when transmitting the preamble via beam scanning by using the bits of the SS / PBCH index and PRACH mask index, and all possible allocation methods can be included within the scope of this disclosure. As a more specific allocation example, the 4 bits of the PRACH mask index field can indicate the location of one time / frequency resource of the preamble to be beam scanned within the frame, 4 of the 6 bits of the SS / PBCH index field can be used to indicate the location of another time / frequency resource of the preamble to be beam scanned within the frame, and the remaining 2 bits can be used to indicate the offset value relative to the transmit power configured during the connection process between the UE and the first TRP.

[0401] As another allocation example, the four bits of the PRACH mask index field can indicate the location of a time / frequency resource for the preamble to be beam-scanned within the frame. Four of the six bits of the SS / PBCH index field can be used, for example, to indicate the location of multiple additional time / frequency resources for the preamble to be beam-scanned within the frame, and the remaining two bits can be used to indicate an offset relative to the transmit power configured during the connection process between the UE and the first TRP. When the one bit of the UL / SUL indicator is additionally used for beam-scanning preamble allocation, this one bit can be used to allocate time / frequency resources for the beam direction of the preamble and / or the transmit power of the preamble to be transmitted.

[0402] The beam scan indicator field can be configured to 1 bit (e.g., for DCI in PDCCH commands) to determine the PL offset and resolve unknown UL-only TRP issues. When the bit value of the beam scan indicator field is set to '1', it can instruct the UE to send a preamble by performing a beam scan, and when the bit value of the beam scan indicator field is set to '0', it can instruct the UE to send a preamble without beam scanning.

[0403] In cases where the UE can form a quasi-omnidirectional transmission beam pattern in the FR1 band and / or the UE can form a directional transmission beam pattern in the FR2 and FR2-1 bands, when the type of the UL signal to be transmitted by the UE is assumed to be a preamble, the UE can transmit a preamble for TA or PL offset determination, TT offset determination, TT offset estimation, and TT offset collection through the process described below.

[0404] First, the network (e.g., the first TRP (e.g., macro TRP), the base station (gNB), or the network (NW)) can instruct the UE to transmit preambles for TA or PL offset determination, TT offset determination, TT offset estimation, and TT offset collection in a quasi-omnidirectional or directional manner using one or more of the DCI, MAC-CE, or RRC signaling used for PDCCH commands. In this case, the network can instruct the UE to transmit a preamble configured by a resource configuration using the indicated time / frequency resources. In this case, the aforementioned OOS problem may be resolved, but the unknown UL-only TRP problem may not be resolved. Furthermore, to resolve the unknown UL-only TRP problem, multiple beam scanning preambles can be transmitted in multiple directions.

[0405] One or more fields used for TA / PL offset determination, TT offset determination, TT offset estimation, and TT offset collection for DCI, MAC-CE, or RRC signaling for PDCCH commands can be configured as follows.

[0406] (1) RRC and / or MAC-CE messages may include message fields such as PL offset determination indicator, beam scan indicator, random access preamble index and PRACH preamble resource configuration.

[0407] The PL Offset Determination Indicator field can be configured to 1 bit. When the bit information of the PL Offset Determination Indicator field is set to '1', it indicates that the RRC and / or MAC-CE messages are used by the network to determine the PL offset value for UL TRP only. The PL Offset Determination Indicator field can be omitted because the beam scan indicator field following it can serve the same function as the PL Offset Determination Indicator field. Therefore, when using the beam scan indicator field, the PL Offset Determination Indicator field can be omitted.

[0408] The beam scan indicator field can be configured to 1 bit, for example, for PL offset determination and for resolving unknown UL-only TRP issues via RRC and / or MAC-CE messages. When the bit information of the beam scan indicator field is set to '1', the beam scan indicator field can instruct the UE to send a preamble using beam scanning. When the bit information of the beam scan indicator field is set to '0', the beam scan indicator field can instruct the UE to send a preamble without beam scanning.

[0409] The random access preamble index field indicates the index of the preamble to be generated and sent.

[0410] The PRACH preamble resource configuration field can indicate information about the location of time / frequency resources for transmitting the preamble. When beam scanning is indicated by information from one of the aforementioned fields (e.g., the beam scan indicator field), the preamble resource configuration time / frequency resources can indicate all time or frequency resources for which beam scanning is performed. Conversely, when beam scanning is indicated by information from one of the aforementioned fields (e.g., the beam scan indicator field), the preamble resource configuration time / frequency resources can indicate the configuration of one or more time or frequency resources for which beam scanning is not performed.

[0411] (2) In the case of DCI for PDCCH commands, the DCI 1_0 format for PDCCH commands can be configured to include, in addition to the existing fields, PL offset determination indicator (or asymmetric indicator) and / or beam scan indicator fields.

[0412] The PL offset determination indicator field can be configured to 1 bit. When the bit information of the PL offset determination indicator field is set to '1', the DCI can indicate that the DCI is used for the network to determine the PL offset value for only the UL TRP. In this case, the PL offset determination indicator field can be omitted because the beam scan indicator field following the PL offset determination indicator field can perform the function of the PL offset determination indicator field.

[0413] Furthermore, when the PL offset determination indicator field is additionally configured and its bit information is set to '1', the UL / SUL indicator, SS / PBCH index, or PRACH mask index in the current 5G NR specification becomes invalid. Therefore, the UL / SUL indicator, SS / PBCH index, and / or PRACH mask index fields defined in the current 5G NR specification can be multiplexed for transmissions toward UL-only TRPs. For example, the UL / SUL indicator can be multiplexed as a beam scanning indicator as described below. In other words, when the bit information of the UL / SUL indicator is set to '1', the UE can determine that beam scanning is to be performed, and when the bit information of the UL / SUL indicator is set to '0', the UE can determine that beam scanning is not to be performed.

[0414] Furthermore, the SS / PBCH index and PRACH mask index can be reused as fields for allocating time / frequency resources for the beam direction of the preamble and / or the transmit power of the preamble to be transmitted, depending on whether beam scanning is performed. For example, when the bit information of the PL offset determination indicator is set to '1' and the bit value of the UL / SUL indicator is set to '1', the network can allocate time / frequency resources and / or transmit power when transmitting the preamble via beam scanning by using the bits of the SS / PBCH index and PRACH mask index. This is merely an example, and all possible allocation methods are included within the scope of this disclosure.

[0415] As an example of allocation, the four bits of the PRACH mask index field can indicate the location of a time / frequency resource of the preamble to be beam-scanned within the frame, four of the six bits of the SS / PBCH index field can be used to indicate the location of another time / frequency resource of the preamble to be beam-scanned within the frame, and the remaining two bits can be used to indicate the offset value relative to the transmit power configured during the connection process between the UE and the first TRP.

[0416] As another allocation example, the four bits of the PRACH mask index field can indicate the location of a time / frequency resource for the preamble to be beam-scanned within the frame. Four of the six bits of the SS / PBCH index field can be used, for example, to indicate the location of multiple additional time / frequency resources for the preamble to be beam-scanned within the frame, and the remaining two bits can be used to indicate an offset relative to the transmit power configured during the connection process between the UE and the first TRP. When the one bit of the UL / SUL indicator is additionally used for the allocation of the beam-scanning preamble, the one bit of the UL / SUL indicator can be used to allocate the time / frequency resources for the beam direction of the preamble and / or the transmit power of the preamble to be transmitted.

[0417] The beam scan indicator field can be configured to 1 bit (e.g., for DCI in PDCCH commands) to determine the PL offset and resolve unknown UL-only TRP issues. When the bit value of the beam scan indicator field is set to '1', the UE can determine that it is instructed to use beam scanning to transmit the preamble, and when the bit value of the beam scan indicator field is set to '0', the UE can determine that it is instructed to transmit the preamble without beam scanning.

[0418] Other exemplary embodiments based on the above description are described below.

[0419] After the UE completes initial system access and establishes a link connection for the first TRP (which is a macro TRP), the UE can allow the base station (gNB) to determine the PL offset for the UL-only TRP using either SRS or a preamble. The choice between using SRS or a preamble to determine the PL offset can vary depending on whether the UE establishes the connection in the FR1 or FR2 band.

[0420] In the FR1 case, when considering the use of a preamble based on the PDCCH command DCI mechanism to determine the PL offset, the UE can avoid unknown UL-only TRP issues due to the omnidirectional beam pattern in the FR1 band. Furthermore, since the preamble inherently uses a long CP, uplink OOS issues can also be prevented. Another advantage of using a preamble is that only a single preamble needs to be transmitted. However, in asymmetric scenarios, interference with cells managed by another macro TRP may occur due to the omnidirectional beam pattern, so it may be necessary to adjust the transmit power differently during preamble transmission compared to existing PDCCH command DCI. Additionally, in the case of CFRA preamble transmission based on PDCCH command DCI according to the current 5G NR specification, since the first TRP can indicate the TRP for receiving the preamble, the UE needs to monitor the response to the transmitted preamble.

[0421] However, in asymmetric scenarios, the first TRP, acting as a macro TRP, may not be able to indicate a single TRP for the PRACH mask index (i.e., time slot or frequency resource group) of the preamble to be transmitted by the UE. Therefore, the first TRP, acting as a macro TRP, needs to notify all possible UL-only TRPs of the corresponding PRACH mask index before monitoring the preamble transmitted by the UE. Due to the delay caused by this process, a problem may arise where the RAR monitoring time exceeds the limit after the UE transmits the preamble. Therefore, it is necessary to use a new field in the DCI to deactivate RAR monitoring for the UE. Furthermore, the bit index of the new field in the DCI can notify the UE of asymmetric scenarios, and fields such as the SS / PBCH index, UL / SUL indicator, and PRACH association indicator can be reused to configure other information.

[0422] Alternatively, when SRS is used for PL offset determination in the FR1 band, uplink OOS becomes an issue. However, this issue can be resolved by reusing aperiodic SRS configurations and transmissions without requiring the beam-switching modes used in existing uplink beam management. Here, in addition to the transmission timing of each SRS configuration set being adjusted at the sample level, the above... Figure 9 The TA offset Δ described in the text TA (e.g., 0 or T) CP In addition to / 2), the SRS configuration set can be used for uplink beam management in connected states.

[0423] In the FR2 band, when considering using a preamble based on the PDCCH command DCI mechanism to determine the PL offset, a long CP can help resolve the uplink OOS problem. However, to address the unknown UL TRP-only issue, the UE needs to send multiple beam-scanning preambles, resulting in a high degree of specification impact on the preamble transmission process. Furthermore, a drawback of using beam-scanning preambles for the PL offset is that, based on the UL TRP-only receive beam pattern, the preamble may not be detected in advance.

[0424] Alternatively, when SRS is used for PL offset determination in the FR2 band, unknown UL-only TRP and uplink OOS issues may arise, but these problems can be addressed by reusing existing periodic or semi-persistent SRS configurations and transmissions used in existing uplink beam management. Here, in addition to the transmission timing of each SRS configuration set being adjusted at the sample level as described above... Figure 9 The TA offset Δ described in the text TA (e.g., 0 or T) CP In addition to / 2), the SRS configuration set can be used for uplink beam management in the connected state.

[0425] Therefore, when determining the PL offset in the FR1 band, the following proposal 1 can be used, considering that all problems can be solved.

[0426] [Proposal 1]

[0427] For the PL offset determination of the PDCCH command DCI based on the FR1 band, a new bit DCI field can be introduced into DCI format 1_0.

[0428] A new DCI field can exist when the corresponding RRC parameter is activated and there is no TCI state configured with a PL offset.

[0429] The bit field index 0 of the new DCI field can indicate that PL offset determination is not performed during PRACH transmission, and response monitoring of PRACH transmission is performed.

[0430] The bit field index 1 of the new DCI field can indicate that the PL offset was determined in the PRACH transmission, and no response monitoring of the PRACH transmission is performed.

[0431] Based on the bit field index 1 of the new DCI field, the field to be reused can indicate different information as described above.

[0432] When performing PL offset determination in the FR2 band, the following proposal 2 can be used to minimize the influence of the specification.

[0433] [Proposal 2]

[0434] For SRS-based PL offset determination in the FR2 band, new fields can be added to the SRS configuration according to the current 5G NR specifications.

[0435] For periodic or semi-persistent SRS transmissions based on the multi-beam directional beamforming mode of the current 5G NR specification, a new field related to the advance of transmission timing can be specified in the RRC / SRS trigger MAC-CE format.

[0436] To consider a general solution for determining PL offset in both the FR1 and FR2 frequency bands, the following proposal 3 can be used.

[0437] [Proposal 3]

[0438] For SRS-based PL offset determination, new fields can be added to the SRS configuration according to the current 5G NR specifications.

[0439] In the FR2 band, for periodic or semi-persistent SRS transmissions in multi-beam directional beamforming modes according to the current 5G NR specifications, a new field related to transmission timing advance can be specified in the RRC / SRS trigger MAC-CE format.

[0440] In the case of the FR1 band, for non-periodic SRS transmissions in the existing omnidirectional beamforming mode, a new field related to the advance of transmission timing can be specified in the DCI (e.g., DCI format 0_1, 0_2, or 1_1).

[0441] For the unified TCI framework of 3GPP Rel-17 and the unified TCI of 3GPP Rel-18, the new 1-bit field configured in DCI format 1_0 has been defined differently. The optimal solution can be achieved when a single specification supports both unified TCI frameworks. From this perspective, the single specification approach for the Rel-17 / Rel-18 unified TCI framework is recommended as follows.

[0442] (1) A new 1-bit DCI field can be configured in DCI format 1_0 to indicate the PL offset of the PDCCH command PRACH. The existence of the new 1-bit DCI field is assumed when the corresponding RRC parameter for configuring the DCI field is activated and at least one TCI state is configured together with the PL offset.

[0443] (2) When indicating a joint / UL TCI state in the unified TCI framework of Rel-17, bit field index 0 of the new 1-bit field of DCI format 1_0 may indicate that there is no PL offset associated with the indicated TCI state. Bit field index 1 of the new field may indicate that the PL offset associated with the indicated TCI state is included in the PRACH transmit power calculation. For bit field index 1 of the new field, other unnecessary fields such as SS / PBCH index and / or UL / SUL indicator may be reused to indicate other information (e.g., information related to transmit power adjustment, the number of repetitions of the corresponding PRACH preamble, the indicated TCI state, or whether monitoring is not performed on the corresponding PRACH preamble).

[0444] (3) When two joint / UL TCI states are indicated in the unified TCI framework of Rel-18, bit field index 0 of the newly defined field in the DCI can indicate that there is no PL offset associated with the indicated TCI state, similar to the case of one indicated joint / UL TCI state. Bit field index 1 of the new field can indicate that the PL offset associated with one of the two indicated TCI states is included in the PRACH transmit power calculation. For bit field index 1 of the new field, other unnecessary fields such as the SS / PBCH index, UL / SUL indicator, and PRACH association indicator can be reused to indicate other information (e.g., a 1-bit indicator for one of the two indicated TCI states, information related to transmit power adjustment, the number of repetitions of the corresponding PRACH preamble, the indicated TCI state, or whether monitoring is not performed on the corresponding PRACH preamble). For reference, when simultaneous uplink data transmission is required, whether simultaneous transmission is performed by the PL offset associated with the two TCI states can be indicated as other information.

[0445] [Proposal 4]

[0446] A new 1-bit DCI field can be introduced in DCI format 1_0 to indicate the PL offset of the PDCCH command PRACH.

[0447] (1) A new 1-bit DCI field may exist when the corresponding RRC parameter (i.e., the new RRC parameter, which configures the presence of a 1-bit DCI field) is activated and at least one TCI state is configured together with the PL offset.

[0448] (2) The bit field index 0 of the new 1-bit field of the DCI field can indicate that there is no PL offset associated with the indicated TCI state and perform response monitoring for PRACH transmission.

[0449] (3) The bit field index 1 of the new 1-bit field of the DCI field can indicate that the PL offset associated with the indicated TCI state is included in the PRACH transmit power calculation and that no response monitoring of the corresponding PRACH transmission is performed.

[0450] (4) When indicating a joint / UL TCI status in the unified TCI framework of Rel-17, the SS / PBCH index and / or UL / SUL indicator can be reused to indicate other information for the bit field index 1 of the new 1-bit field of the DCI field.

[0451] (5) When indicating two combined / UL TCI states in the unified TCI framework of Rel-18, the SS / PBCH index, UL / SUL indicator and / or PRACH associated indicator can be reused to indicate other information for bit field index 1 of the new 1 bit field of the DCI field.

[0452] In the FR1 band, considering that the preamble based on the PDCCH command DCI mechanism is used for PL offset determination, the UE can avoid the unknown UL-only TRP (UT) problem caused by the omnidirectional beam pattern in the FR1 band. Furthermore, since the preamble inherently uses a long CP, it can help prevent uplink OOS problems. Another advantage of using a preamble is that only a single preamble transmission is required. The network (NW) can determine the PL offset by requiring all UTs managed by the first TRP (which acts as a macro TRP) to listen for PDCCH command DCI-based preamble transmissions within the time slot and frequency resource group configured by the PRACH mask index of the DCI.

[0453] In the FR2 band, considering that the preamble based on the PDCCH command DCI mechanism is used for PL offset determination, and since the UE uses a long CP to send the preamble, the preamble can help solve the uplink OOS problem. However, to solve the unknown UL-only TRP problem, multiple beam scan preambles need to be sent, which may lead to significant specification changes in the preamble transmission process.

[0454] On the other hand, when SRS is used to determine the PL offset in the FR2 band, both unknown UL TRP issues and uplink OOS issues may occur. However, such issues can be addressed by reusing the periodic or semi-persistent SRS configurations and transmissions used in the uplink beam management of the current 5G NR specification (based on beam switching modes) and by adjusting the transmission timing of each SRS configuration set.

[0455] In summary, when using SRS or preamble in both FR1 and FR2 bands, the PL offset can be determined by using the preamble. Otherwise, the PL offset can be determined by using the preamble in FR1 band and by using SRS in FR2 band. Proposal 4a for determining the PL offset by using the preamble in FR1 band and by using SRS in FR2 band is as follows.

[0456] [Proposal 4a]

[0457] To indicate the PL offset of the PDCCH command PRACH in the FR1 band, two joint / UL TCI states can be indicated in the unified TCI framework of Rel-18.

[0458] The DCI field may exist when the corresponding RRC parameter (i.e., a new RRC that configures the presence of a 1-bit DCI field) is activated and there is no TCI state configured with a PL offset.

[0459] >>The bit field index 0 of the DCI field can indicate that a PL offset determination has been performed.

[0460] >>The bit field index 1 of the DCI field can indicate that a PL offset determination has been performed.

[0461] >>As a further study (FFS): Does bit field index 0 or bit field index 1 of the DCI field indicate PL RS and / or uplink power control parameters used for PRACH transmission?

[0462] The DCI field may exist when the corresponding RRC parameter is activated and one or more TCI states are configured with a PL offset.

[0463] >>The bit field index 0 of the DCI field can indicate that the PL offset associated with the first indicated joint / UL TCI state is included in the PRACH transmit power calculation.

[0464] >>The bit field index 1 of the DCI field can indicate that the PL offset associated with the second indicated joint / UL TCI state is included in the PRACH transmit power calculation.

[0465] >>A study on a method for indicating the following information in DCI format 1_0 using a new 1-bit DCI field:

[0466] >>>PL RS for PRACH transmission

[0467] >>>Other power control parameters for PRACH transmission

[0468] >>> Transmit beam used for PRACH transmission

[0469] [Proposal 4b]

[0470] To indicate the PL offset of the PDCCH command PRACH after PL offset determination in the FR2 band, two joint / UL TCI states can be indicated in the unified TCI framework of the Rel-18 specification.

[0471] The DCI field can exist when the corresponding RRC parameter (i.e., a new RRC that configures the presence of a 1-bit DCI field) is activated and one or more TCI states are configured with a PL offset.

[0472] >>The bit field index 0 of the DCI field can indicate that the PL offset associated with the first indicated joint / UL TCI state is included in the PRACH transmit power calculation.

[0473] >>The bit field index 1 of the DCI field can indicate that the PL offset associated with the second indicated joint / UL TCI state is included in the PRACH transmit power calculation.

[0474] >>A study on a method for indicating the following information in DCI format 1_0 using a new 1-bit DCI field:

[0475] >>>PL RS for PRACH transmission

[0476] >>>Other power control parameters for PRACH transmission

[0477] >>> Transmit beam used for PRACH transmission

[0478] When beam scanning is performed to calculate the PL offset using a preamble as the UL signal, the UE transmits the preamble by performing beam scanning on a predefined set of directions with network-specified preambles, thereby reducing latency.

[0479] The advantage of using a preamble for beam scanning is that, compared to SRS, the PRACH preamble can conceptually be considered to have a very long CP. Therefore, even when the aforementioned uplink OOS problem occurs, UL TRP alone can successfully estimate the reverse link synchronization and / or reverse link received power, which is related to the PL offset described below.

[0480] When the UE performs beam scanning using a preamble, the first TRP, acting as a macro TRP, can deliver a predefined preamble along with RO information to the UE. Therefore, the UE receiving the predefined preamble along with RO information can transmit the preamble provided by the first TRP at the transmission power calculated as described above, the transmission power initially received from the first TRP as is, or a modified transmission power. In this case, the UE can transmit the preamble provided by the first TRP by completing an RRC reconfiguration between the first TRP and the UE (i.e., after the RRC reconfiguration is completed). Figure 10a The UL-synchronized transmission timing obtained in step S1023 is used to transmit the preamble by scanning the beam in a predefined set of directions.

[0481] When only the UL TRP receives different preambles from multiple UEs simultaneously or in a partially overlapping manner, and the preambles are used for beam scanning, only the UL TRP can successfully distinguish the preambles and estimate the reverse link synchronization.

[0482] When the first TRP, acting as the macro TRP, instructs the UE to perform beam scanning using a PRACH preamble, the method for delivering instruction information may include delivering a separate MAC-CE to the UE. This MAC-CE includes a Physical Cell Identifier (PCI) field, a Random Access Preamble Index field, a RO Configuration / Index field, and a Scan / Repeat Count field. Here, the PCI field may indicate PCI information, the Random Access Preamble Index field may indicate information about the preamble specified by the network, the RO Configuration / Index field may indicate the RO configuration and / or RO index (which is location information for the time and frequency resources used to send the preamble generated from the Random Access Preamble Index field), and the Scan / Repeat Count field may indicate the number of times the preamble is scanned and / or repeated.

[0483] The RO configuration described above does not indicate a single RO, but rather a list of grouping configurations when multiple ROs are grouped together, where the ROs in the configuration list can be used for scanning / repeating the preamble. Furthermore, the RO index can indicate the index of the multiple ROs used for scanning / repeating.

[0484] In the separate MAC-CE configuration described above, the PCI field may not be included in the separate MAC-CE.

[0485] When the first TRP, acting as the macro TRP, instructs the UE to perform beam scanning using a PRACH preamble, another method for delivering instruction information may include instructing the UE to perform beam scanning using a PRACH preamble via RRC signaling. Similar to MAC-CE, RRC signaling may include information such as a PCI field, a random access preamble index field, an RO configuration / index field, and a scan / repetition count field. Furthermore, as mentioned above, similar to MAC-CE, the PCI field may not be included.

[0486] When beam scanning is performed using SRS as the UL signal, the UE can transmit SRS by performing beam scanning in a predefined set of directions for different transmission times to address uplink OOS issues. Therefore, transmitting SRS via beam scanning may result in longer latency compared to transmitting a preamble via beam scanning. In this case, the following problems may arise when using SRS for beam scanning.

[0487] First, from the perspective of the UE, whose reference timing is already aligned with the first TRP, when using an SRS with a normal-length CP, only the UL TRP located near the UE can be in an OOS state with the UE. Therefore, only the UL TRP has the problem of difficulty in decoding signals received from the UE.

[0488] Second, to prepare for situations where only the UL TRP located near the UE is in an OOS (Out of Service) state, only the UL TRP can use an energy estimation scheme. However, when using an energy estimation scheme to detect SRS (Sentence Responding to Messages) transmitted by the UE, only the UL TRP has the problem of difficulty in identifying the UE that transmitted the SRS.

[0489] Third, when only UL TRP receives SRS from multiple UEs simultaneously, the SRS is measured as a mixed energy level due to the multiple SRSs, so the UE that sent the SRS cannot be identified.

[0490] Fourth, the first TRP can schedule UEs to send SRS sequentially to prevent multiple UEs from sending SRS simultaneously. However, when there is an SRS sent by a second UE under the control of another macro TRP (or head TRP), the UL TRP alone cannot distinguish between the UE sending SRS under the control of the first TRP and the second UE sending SRS under the control of another macro TRP.

[0491] Fifth, the method of sequentially transmitting SRS under the control of multiple UEs in the first TRP is very inefficient in terms of resource efficiency. Furthermore, the following describes the process of searching for a UL-only TRP and obtaining the timing advance between the UE and the UL-only TRP using beam scanning with SRS as the UL signal, the problems encountered when searching for a UL-only TRP using SRS in beam management, and the method for searching for a UL-only TRP.

[0492] <Using existing SRS to search for UL TRP-only issues>

[0493] The UL TRP that contributes the most to the uplink service transmission of the UE is the TRP located near the UE. However, the TRP located near the UE (i.e., adjacent) is very likely to be in an OOS state with the first TRP (i.e., macro TRP or head TRP).

[0494] The TRP search method or beam search method using SRS according to the current 5G NR specification has the advantage of minimal impact on the 5G NR specification because multiple SRS can be transmitted by multiplexing the SRS configuration through RRC signaling. However, because the TRP search method or the beam search method using SRS does not solve the OOS problem during SRS transmission due to short CP, it may be difficult to perform SRS estimation for UL TRPs located near the UE.

[0495] <Method for searching UL TRP only using existing SRS>

[0496] When comparing the first distance between the UE and the first TRP (which is a macro TRP) and the second distance between the UE and the UL-only TRP, the second distance is much shorter than the first distance. In other words, it can be assumed that the distance between the UE and the UL-only TRP is closer than the distance between the UE and the first TRP. This is because there is no advantage to uplink transmission from the UE to the UL-only TRP when the second distance has a longer value than the first distance.

[0497] Specifically, because the TRP used as a UL-only TRP has higher uplink transmission efficiency as it gets closer to the UE, the macro TRP needs to progressively find a suitable UL-only TRP for the UE. In other words, in the first phase of the search, the macro TRP can find a UL-only TRP within a predetermined distance from the UE. When the macro TRP fails to find a UL-only TRP for uplink transmission in the first phase of the search, it can perform a second phase of the search, which is set to a distance greater than that of the first phase search. In other words, the macro TRP can search for UL-only TRPs located within the distance of the UE in the second phase of the search.

[0498] To search for UL-only TRPs within the first-stage distance, the first TRP, acting as a macro TRP, can set a TA value of 1 / 3 of the TA value between the first TRP and the UE as the TA value for searching UL-only TRPs. Furthermore, to search for UL-only TRPs within the second-stage distance, the first TRP can set a TA value of 2 / 3 of the TA value between the first TRP and the UE as the TA value for searching UL-only TRPs. Moreover, to search for UL-only TRPs within the third-stage distance, the first TRP can set the TA value between the first TRP and the UE to the TA value for searching UL-only TRPs. Here, the values ​​'1 / 3' and '2 / 3' are merely examples and can be set to other values ​​equal to or less than 1. For ease of description, the TA values ​​for the first-stage search, second-stage search, and third-stage search will be referred to as 'TA1', 'TA2', and 'TA3', respectively.

[0499] The first TRP, acting as a macro TRP, can instruct the UE to send a predetermined number of SRS messages to the adjacent UL-only TRP for each TA, using TA1, TA2, and TA3 as TA values ​​for SRS transmission. The UE receiving this instruction can then send SRS messages based on the instructions from the first TRP. In this scenario, the UE can send SRS messages in all directions by changing the combined / UL TCI state of each TA.

[0500] The macro TRP can use one or more of RRC signaling, MAC-CE, or DCI to deliver TA1, TA2, and TA3 to the UE. According to the 5G NR specification, the TAC MAC-CE may include a TA value field. In this disclosure, a UL-only TRP indicator field may be added to allow identification of the TA value indicated by the TA value field, which indicates the TA value between the UL-only TRP and the UE. Furthermore, TA1, TA2, and TA3 can be represented by the TA value field. The TAC MAC-CE according to an exemplary embodiment of this disclosure may include the fields shown in Table 1 below.

[0501] [Table 1]

[0502]

[0503] Furthermore, according to another exemplary embodiment of this disclosure, the TAC MAC-CE may also include a joint / UL TCI status field, and may notify the UE of the TCI status to which each of the TA1, TA2, and TA3 values ​​applies. The TAC MAC-CE further including a joint / UL TCI status field may include the fields shown in Table 2 below.

[0504] [Table 2]

[0505]

[0506] <TA Acquisition when completing a UL TRP search only>

[0507] When a UL-only TRP is successfully located using the SRS method, the UL-only TRP that appropriately receives the SRS sent by the UE can notify the first TRP, which is a macro TRP, of the search result. Using the search result, the macro TRP can calculate the TA value between the UE and the UL-only TRP. Furthermore, the first TRP, which is a macro TRP, can notify the UE of the calculated TA value between the UE and the UL-only TRP using a TAC command. The UE can then obtain the TA value with the UL-only TRP based on the TAC command received from the first TRP. Therefore, during uplink transmissions toward the UL-only TRP, the UE can perform uplink transmissions toward the UL-only TRP using the TA value based on the TAC command.

[0508] Figure 13 This is a conceptual diagram illustrating the case where only the UL TRP sends an estimate to the first TRP in an asymmetric mTRP environment.

[0509] refer to Figure 13 Base station 1341 can communicate with UE 1311 in the cell located at base station 1341 using multiple TRPs 1301, 1302, and 1303. Figure 13 In the example, only three TRPs 1301, 1302 and 1303 are shown for the sake of simplicity. However, the number of TRPs that can be included in base station 1341 is not limited to three and can be more than three or less than three.

[0510] also, Figure 13 The exemplary embodiment assumes that three different TRPs are included in a base station 1341, wherein the first TRP 1301 may have a first cell area 1110, the second TRP 1302 may have a second cell area 1320, and the third TRP 1303 may have a third cell area 1330. Figure 13 The first TRP 1301 shown can be referred to as a macro TRP or header TRP as described above, and the first TRP 1301 can perform DL and UL communication with UE 1311. The second TRP 1302 and the third TRP 1303 can be the UL-only TRPs described above. Therefore, the second TRP 1302 and the third TRP 1303 can be TRPs that do not transmit any signals in the downlink, or they can be TRPs that transmit only minimal downlink signals.

[0511] Figure 13 The UE 1311 shown in the figure can be Figure 10a and Figure 10b The UE #0 described herein can be in an RRC connection state with the first TRP 1301. The first TRP 1301 can instruct the UE 1311 to send an SRS or a preamble. Figure 13 As shown, UE 1311 can transmit SRS or preamble based on the number of UL signals scanned by each set in the beam direction configurable by UE 1311, indicated by the first TRP 1301, and based on the transmission timing of each set.

[0512] When UE is like Figure 12 As shown or as described above Figure 10b When performing beam scanning as in step S1040, each of ULTRPs 1302 and 1303 can estimate the uplink received (Rx) power and the receive timing corresponding to the path loss (PL) based on the SRS or preamble associated with the UE space. After estimating the uplink received power and receive timing, each of ULTRPs 1302 and 1303 can send the estimated results of the uplink received power and receive timing to base station 1341 via backhauls 1351 and 1352 respectively connected between base station 1341 and ULTRPs 1302 and 1303, such as... Figure 13As shown. Furthermore, base station 1341 can transmit the uplink received power and received timing received from each of UL TRPs 1302 and 1303 via backhaul 1353 connected to first TRP 1301. For example... Figure 13 The delivery method shown via a wired connection is merely an example and is not limited thereto. For instance, when only each of UL TRPs 1302 and 1303 is wirelessly connected to the first TRP 1301, only each of UL TRPs 1302 and 1303 can directly transmit estimates of uplink received power and receive timing to the first TRP 1301. In this disclosure, no particular limitations are imposed on the method by which the first TRP 1301 receives estimates of uplink received power and receive timing from only each of UL TRPs 1302 and 1303.

[0513] After receiving estimates of uplink receive power and receive timing from each of UL TRPs 1302 and 1303, the first TRP 1301 can compare the DL PL value and / or DL ​​receive timing from the first TRP 1301 to UE 1311 with the uplink receive power and / or uplink receive timing from UE 1311 to UL TRPs 1302 or 1303. Based on the comparison, the first TRP 1301 can calculate (or estimate) the PL offset required to calculate transmit power when UE 1311 performs uplink transmissions to UL TRPs 1302 and 1303, and the TT offset required to calculate uplink transmit timing when UE 1311 performs uplink transmissions to UL TRPs 1302 and 1303.

[0514] Here, in the uplink power control process using PL offset, uplink reception at the ULTRP-only location without downlink transmission requires power control and timing advance based on the first TRP 1301. In this case, there may be a limit on the maximum supported value of the difference between the distance between the first TRP and UE 1311 and the distance between UE 1311 and the ULTRP-only location. Such a limit may not always be a good solution. When such a limit is not present, the PL measured using the DL PL RS transmitted from the first TRP 1301 may not reflect the actual PL from UE 1311 to the ULTRP-only location 1302 or 1303. To reflect the actual PL, the difference between the DL PL from the first TRP 1301 to UE 1311 and the UL PL from UE 1311 to the ULTRP-only location 1302 or 1303 may be required. The difference between DL PL and UL PL from UE 1311 to UL TRP 1302 or 1303 only (i.e. PL offset) can be calculated as 'PL offset = DL PL − UL PL'.

[0515] Therefore, regarding PL offsets, specifications are needed regarding how to configure PL offsets, how PL offsets are associated with joint / UL TCI states, and how PL offsets are used for uplink power control. As an example of a procedure for updating a UL PL for a joint / UL TCI state (i.e., a procedure for uplink power control), the following steps can be performed.

[0516] (1) When a UE 1311 that expects to connect to a UL TRP 1302 or 1303 only has a joint / UL TCI state activated by the first TRP 1301, but the activated joint / UL TCI state is not included in the UE’s current active TCI state list, or when a UE 1311 attempts to initially access or connect to a UL TRP 1302 or 1303 only, the UL PL can be calculated as shown in Equation 1 below.

[0517] [Equation 1]

[0518]

[0519] In Equation 1, the first TRP 1301 can be considered as a network entity that manages the PL offsets associated with the first TRP 1301. Furthermore, based on the reference used to define the PL offsets, the negative sign in Equation 1 can be replaced with a positive sign.

[0520] (2) When a UE 1311 that expects to connect to a UL TRP 1302 or 1303 only has a joint / UL TCI state activated by the first TRP 1301 and the activated joint / UL TCI state is included in the UE’s current active TCI state list, or when the UE 1311 continuously updates the UL PL after establishing an initial access / connection with a UL TRP 1302 or 1303 only, the UL PL can be updated from the immediately preceding UL PL as shown in Equation 2 below.

[0521] [Equation 2]

[0522]

[0523] In Equation 2, the differential PL offset value is the difference between the updated UL PL and the immediately preceding UL PL, and therefore can also be called the incremental PL value. UE 1311 can identify (or receive) the incremental PL value from the network.

[0524] Furthermore, an example of the immediately preceding UL PL could be the difference between the 'immediately preceding DLPL estimated according to the DL PL RS' and the PL offset received (or identified) from the first TRP, and the UL PL update could be calculated by applying this difference as shown in Equation 3 below.

[0525] [Equation 3]

[0526]

[0527] For example, in Equation 3, when a joint / UL TCI state is activated and not included in the list of currently active TCI states, the incremental PL value can be set to 0 dB on the dB scale or 1 on the real scale.

[0528] During the aforementioned uplink power control process, the control information received from the network may include PL offset and differential PL offset values. The method by which the first TRP 1301 or the network delivers the control information received from the network and the mapping information of the joint / UL TCI state associated with the PL offset to the UE 1311 can vary. The method for transmitting the control information and the mapping information of the joint / UL TCI state associated with the PL offset is further described below.

[0529] Furthermore, the first TRP 1301 can calculate the TT offset required for calculating the transmission timing of UE 1311 transmitting UL signals to UL TRPs 1302 and / or 1303 using the receive timing value of the first TRP 1301 and the receive timing values ​​received from UL-only TRPs 1302 and 1303. Here, instead of the TT offset, the first TRP 1301 can calculate the absolute TA value for transmission from UE 1311 to UL-only TRPs 1302 and 1303 using the receive timing value of the first TRP 1301 and the estimated receive timing values ​​received from UL-only TRPs 1302 and 1303.

[0530] The process of defining the transmission timing of UE signals by reflecting the TT offset is described.

[0531] Uplink reception at a UL-only TRP without downlink transmission requires power control and timing advance based on the first TRP. In this case, there may be a limit on the maximum supported value of the difference between the first distance between the first TRP and the UE and the second distance between the UE and the UL-only TRP. Such a limitation may not always be a good solution. When such a limitation does not exist, the transmission timing of UE-transmitted signals received from the first TRP may not reflect the transmission timing of signals transmitted from the UE to the UL-only TRP. Here, the transmission timing of UE-transmitted signals received from the first TRP can indicate a TA value, which indicates the transmission timing of signals transmitted by the UE to the first TRP.

[0532] To reflect the actual transmission timing of the UL-only TRP, it may be necessary to consider the difference between the transmission timing at which the UE sends a signal to the first TRP (received from the first TRP) and the reception timing at which the UL-only TRP receives the signal when the UE sends a signal to the UL-only TRP at that transmission timing. In other words, it may be necessary to consider the value shown in Equation 4 below.

[0533] [Equation 4]

[0534]

[0535] Regarding TT offset, it may be necessary to specify the configuration of the TT offset and its association with the Joint / UL TCI state, as well as whether the TT offset is used for uplink power control. The procedure for updating an uplink TT for a Joint / UL TCI state is described below. In other words, the procedure for controlling uplink transmit timing is described below.

[0536] (1) When a UE that expects to connect to a UL TRP has a joint / UL TCI state activated by the first TRP, but the activated joint / UL TCI state is not included in the UE’s current active TCI state list, or when the UE attempts to initially access / connect to a UL TRP, the uplink transmission timing (ULTT) can be calculated as shown in Equation 5 below.

[0537] [Equation 5]

[0538]

[0539] In Equation 5, the first TRP 1301 can be considered as a network entity that manages the TT offsets associated with the first TRP 1301. Furthermore, the negative sign in Equation 5 can be changed to a positive sign according to the reference used to define the TT offset.

[0540] (2) When a UE that wants to connect to a UL TRP has a joint / UL TCI state activated by the first TRP and the activated joint / UL TCI state is included in the UE’s current active TCI state list, or when the UE updates the UL TT continuously after establishing an initial access / connection with a UL TRP, the UL TT can be updated from the immediately preceding UL TT as shown in Equation 6 below.

[0541] [Equation 6]

[0542]

[0543] In Equation 6, the differential TT offset value is the difference between the updated UL TT and the immediately preceding UL TT, and therefore can also be referred to as the incremental TT value. The UE can receive the incremental TT value from the network.

[0544] For example, when a joint / UL TCI state is activated but not included in the UE's current active TCI state list, the incremental TT value can be set to 0.

[0545] Based on the above operations, the first TRP can be based on the above... Figure 10b In steps S1051 and S1052, the following mapping information is generated from the UL received power and received timing received from the TRP of UL only. In step S1060, the first TRP may send the mapping information to UE #0. The mapping information is the information to be sent to UE #0 and may include PL offset, incremental PL value and / or TT offset (or absolute TA), incremental TT value, and mapping information between UL TCI status or spatial relationship and PL offset or incremental PL value (or TT offset or incremental TT value).

[0546] Figure 14 This is a conceptual diagram illustrating the scenario in an asymmetric mTRP environment where the macro TRP sends mapping information to the UE based on estimates received from the UL TRP only.

[0547] refer to Figure 14 Base station 1441 can communicate with UE 1411 in the cell located at base station 1441 using multiple TRPs 1401, 1402, and 1403. Figure 14 In the example, only three TRPs 1401, 1402 and 1403 are shown for the sake of simplicity, but the number of TRPs that can be included in base station 1441 is not limited to three, and can be more than three or less than three.

[0548] also, Figure 14 The exemplary embodiment assumes that three different TRPs are included in a base station 1441, wherein the first TRP 1401 may have a first cell area 1110, the second TRP 1402 may have a second cell area 1420, and the third TRP 1403 may have a third cell area 1430. Figure 14 The first TRP 1401 shown can be referred to as a macro TRP or header TRP as described above, and can perform DL and UL communication with UE 1411. The second TRP 1402 and the third TRP 1403 can be the UL-only TRPs described above. Therefore, the second TRP 1402 and the third TRP 1403 can be UL-only TRPs that do not transmit any signals in the downlink or only transmit minimal downlink signals.

[0549] Figure 14 The UE 1411 shown can correspond to Figure 10a and Figure 10b The UE #0 described herein can be in an RRC connection state with the first TRP 1401. Figure 14 In the first TRP 1401, the above reference can be executed. Figure 10b The operation of step S1060. That is, the first TRP 1401 can generate mapping information based on the UL received power and UL received timing received from the UL-only TRP, and can send the generated mapping information to the UE 1411. Here, the mapping information is the information to be sent to the UE 1411, and may include PL offset, incremental PL value and / or TT offset (or absolute TA), incremental TT value, and mapping information between UL TCI state or spatial relationship and PL offset or incremental PL value (or TT offset or incremental TT value).

[0550] Because there is a one-to-one mapping between the PL offset and the TT offset, the mapping information between the UL TCI state / space relationship and the PL offset is the same as the mapping information between the UL TCI state / space relationship and the TT offset.

[0551] When mapping UL TCI states and PL offsets, the spatial relationship throughout this disclosure can indicate UL TCI states, can indicate joint TCI states (in which DL TCI states and UL TCI states are integrated for efficiency), or can indicate unified TCI states.

[0552] The following describes exemplary embodiments of the association between PL offset and joint / UL TCI state. Although several exemplary embodiments of the association between PL offset and joint / UL TCI state are described below, the exemplary embodiments can become exemplary embodiments of the association between TT offset and joint / UL TCI state when the PL offset in the exemplary embodiments is replaced with the TT offset and the incremental PL value (or differential TT offset value) is replaced with the incremental TT value. Furthermore, to improve resource utilization efficiency, the exemplary embodiments described below can be extended by configuring the differential PL offset value and TT offset together, and configuring the incremental PL offset value (or differential PL offset value) together with the incremental TT value.

[0553] In the first exemplary embodiment, a single PL offset value can be configured for a single joint / UL TCI state via RRC signaling. While the first exemplary embodiment is simple, it may lack flexibility when dynamic adjustments are required.

[0554] In the second exemplary embodiment, a PL offset value can be configured for a joint / UL TCI state via RRC signaling, and a MAC-CE can update one or more PL offset values ​​for the joint / UL TCI state.

[0555] In a third exemplary embodiment, a list of PL offset configurations can be configured in the bandwidth portion (BWP) or component carrier (CC) via RRC signaling. Each PL offset configuration may include a PL offset value, and a new RRC parameter can be configured for a joint / ULTCI state to indicate one of the configured PL offset configurations.

[0556] In the fourth exemplary embodiment, a list of PL offset configurations can be configured in the BWP or CC via RRC signaling. Each PL offset configuration may include a PL offset value. A new RRC parameter can be configured for a joint / UL TCI state to indicate one of the configured PL offset configurations, and a MAC-CE can update the association between a joint / UL TCI state and a PL offset configuration.

[0557] In the fifth exemplary embodiment, a list of PL offset configurations can be configured in the BWP or CC via RRC signaling. Each PL offset configuration may include a PL offset value, and a MAC-CE may enable or indicate a PL offset configuration for each active joint / UL TCI state.

[0558] In the sixth exemplary embodiment, a list of PL offset values ​​can be configured for a joint / UL TCI state via RRC signaling, and each PL offset value can be applied to the PL range of the corresponding measurement.

[0559] In the seventh exemplary embodiment, for situations where the UE moves rapidly and therefore requires frequent updates (e.g., high mobility situations), or where the PL offset information received via RRC signaling is inaccurate, [the following has been implemented / completed]. Figure 7a and Figure 7b The UE, which is initially accessing the first TRP, can receive a list of PL offset configuration (values) from the first TRP via RRC signaling. Detailed exemplary embodiments related to this are described below with reference to the accompanying drawings.

[0560] Figure 15 This is a conceptual diagram illustrating an example of the relationship between the PL offset configuration, incremental PL configuration, and TCI state configuration required for uplink power control.

[0561] refer to Figure 15 The initial incremental PL configuration 1501 may include incremental PL index 0 (0 dB), incremental PL index 1 (adB), incremental PL index 2 (b dB), incremental PL index 3 (c dB), etc. The initial PL offset configuration 1511 may include PL offset index 1 (A dB), PL offset index 2 (B dB), PL offset index 3 (C dB), etc., and the initial TCI state configuration 1521 may include TCI state 1, TCI state 2, etc.

[0562] The incremental PL index 0 (0 dB) of the initial incremental PL configuration 1501 can be associated with the PL offset index 1 (A dB) and PL offset index 2 (B dB) of the initial PL offset configuration 1511. Furthermore, the PL offset index 1 (AdB) and PL offset index 2 (B dB) of the initial PL offset configuration 1511 can be associated with the TCI state 1 and TCI state 2 of the initial TCI state configuration 1521, respectively.

[0563] Regarding the aforementioned relationships, MAC-CE can notify the UE of the association between the PL index, the incremental PL index, and the combined / UL TCI state. The incremental PL index for the deactivated TCI state can be incremental PL index 0.

[0564] In this case, as indicated by reference numeral 1531 in the attached figure, the initial PL offset configuration 1511 can be updated. Based on the first update 1531, the incremental PL configuration 1502 may include incremental PL index 1 (a dB), incremental PL index 2 (b dB), incremental PL index 3 (c dB), etc., the PL offset configuration 1512 may include PL offset index 1 (A dB), PL offset index 2 (B dB), PL offset index 3 (C dB), etc., and the TCI state configuration 1522 may include TCI state 1, TCI state 2, etc.

[0565] Incremental PL index 2 (b dB) of incremental PL configuration 1502 can be associated with PL offset index 1 (AdB) of PL offset configuration 1512, and incremental PL index 3 (c dB) of incremental PL configuration 1502 can be associated with PL offset index 2 (B dB) of PL offset configuration 1512. Additionally, PL offset index 1 (A dB) of PL offset configuration 1512 can be associated with TCI state 1 of TCI state configuration 1522, and PL offset index 2 (B dB) of PL offset configuration 1512 can be associated with TCI state 2 of TCI state configuration 1522.

[0566] As indicated by reference numeral 1532 in the attached figure, the PL offset configuration 1512 can be updated. Based on the second update 1532, the incremental PL configuration 1503 may include incremental PL index 1 (a dB), incremental PL index 2 (b dB), incremental PL index 3 (c dB), etc., the PL offset configuration 1513 may include PL offset index 1 (A dB), PL offset index 2 (B dB), PL offset index 3 (C dB), etc., and the TCI state configuration 1523 may include TCI state 1, TCI state 2, etc.

[0567] In this scenario, as indicated by reference numeral 1532 in the accompanying drawings, based on the second update 1532 to the PL offset configuration 1513, the incremental PL index 1 (a dB) of the incremental PL configuration 1503 can be associated with the PL offset index 1 (A dB) of the PL offset configuration 1513, and the incremental PL index 2 (b dB) of the incremental PL configuration 1503 can be associated with the PL offset index 3 (C dB) of the PL offset configuration 1513. Furthermore, the PL offset index 1 (A dB) of the PL offset configuration 1513 can be associated with TCI state 1 of the TCI state configuration 1523, and the PL offset index 3 (C dB) can be associated with TCI state 2.

[0568] A UE that receives mapping information in the above manner can store a list of the received mapping information. This information can be sent to the UE by the first TRP (macro TRP) via RRC signaling. Figure 15 As shown, after sending the above information, the first TRP, which has already obtained the PL offset value between the UE and the target UL-only TRP, can... Figure 15 The PL offset configuration (or value) shown in the list of PL offset configurations is mapped to the joint / UL TCI state corresponding to each UL TRP only. The mapping information can be delivered to the UE via MAC-CE.

[0569] when Figure 15 The PL offset configurations (or values) in the configuration list shown do not include the PL offset value estimated by the first TRP. When updates based on the estimated PL offset value are needed, or when there is low correlation with the estimated PL offset value, the first TRP, as a macro TRP (or network entity), can be configured via one or more MAC-CEs to identify such conditions. For this purpose, one or more bits of information can be added to the MAC-CE, and an incremental PL value can be configured, which is the difference between a PL offset configuration (or value) in the PL offset configuration list corresponding to the joint / UL TCI state and the PL offset value estimated (or obtained) by the first TRP.

[0570] In this scenario, an exemplary embodiment for selecting a PL offset configuration (or value) is that the first TRP selects a PL offset configuration (or value) that is closest to the PL offset value estimated (or obtained) by the first TRP. Detailed exemplary embodiments related to this are described below.

[0571] The first detailed exemplary embodiment of the seventh exemplary embodiment described above is described below with reference to the accompanying drawings.

[0572] Figure 16 This is a conceptual diagram illustrating the first PL offset MAC-CE configuration according to the seventh exemplary embodiment.

[0573] refer to Figure 16The MAC-CE can include an octet 0 (1 byte), an octet 1 (1 byte), and an octet 2 (1 byte). That is, the MAC-CE can consist of a total of three octets (3 bytes). The first bit of octet 0 can be a reserved bit and can always be set to 0. The following five bits can be configured as the serving cell ID, and the last two bits can be configured as the BWP ID. The first bit of octet 1 can be configured as the TCI indicator, and the following seven bits can be configured as the Joint / UL TCI Status ID. The first bit of octet 2 can be configured as the offset indicator, the following five bits can be configured as the PL Offset Configuration ID 1, and the last two bits can be configured as the PL Offset Configuration ID 2.

[0574] like Figure 16 As shown, a MAC-CE can configure two or more PL offset configuration IDs for a joint / UL TCI state. The TCI indicator, as the first bit of octet 1, indicates whether the subsequent TCI state ID is a joint TCI state ID or a UL TCI state ID. The offset indicator, as the first bit of octet 2, serves to indicate whether configuration can be performed using the PL offset configuration list received via RRC signaling or not. When configuration can be performed using the PL offset configuration list received via RRC signaling, PL offset configuration ID 1 can correspond to an entry in the PL offset configuration list and can be recognized by the UE. On the other hand, when configuration cannot be performed using the PL offset configuration list received via RRC, the value between the PL offset value indicated by PL offset configuration ID 1 and the PL offset value indicated by PL offset configuration ID 2 can be configured. Here, to reduce the number of bits occupied, the TCI indicator can be omitted. Furthermore, when the offset indicator is also omitted, the configuration can consist only of the PL offset configuration ID as an entry in the PL offset configuration list.

[0575] Figure 17 This is a conceptual diagram illustrating the second PL offset MAC-CE configuration according to the seventh exemplary embodiment.

[0576] refer to Figure 17 A MAC-CE can be composed of octet 0 (1 byte), octet 1 (1 byte), octet 2 (1 byte), octet 3 (1 byte), octet 4 (1 byte), and octet 5 (1 byte). In other words, a MAC-CE can be composed of a total of six octets (6 bytes).

[0577] The first bit of octet 0 can be configured as a reserved bit, which can always be set to 0. The following five bits can be configured as Serving Cell ID 0, and the last two bits can be configured as BWP ID 0. The first bit of octet 1 can be configured as the TCI indicator, and the following seven bits can be configured as the Joint / UL TCI Status ID 0. The first bit of octet 2 can be configured as the Offset Indicator, the following three bits can be configured as the PL Offset Configuration ID 00, the following three bits after PL Offset Configuration ID 00 can be configured as the PL Offset Configuration ID 01, and the last bit can be configured as the Next Indicator 0. The first bit of octet 3 can be configured as a reserved bit, the following five bits can be configured as Serving Cell ID 1, and the last two bits can be configured as BWP ID 1. The first bit of octet 4 can be configured as the TCI indicator, and the following seven bits can be configured as the Joint / UL TCI Status ID 1. The first bit of octet 5 can be configured as an offset indicator, the next three bits can be configured as PL offset configuration ID 10, the next three bits after PL offset configuration ID 10 can be configured as PL offset configuration ID 11, and the last bit can be configured as the next indicator 1.

[0578] like Figure 17 As shown, a MAC-CE can configure two or more PL offset configuration IDs for each joint / UL TCI state. Figure 17 The TCI indicator shown indicates whether the subsequent TCI state is Joint TCI State ID 0 or UL TCI State ID 0, and the offset indicator indicates whether configuration can be performed using the PL offset configuration list received via RRC signaling, or not. When configuration can be performed using the PL offset configuration list received via RRC signaling, PL offset configuration ID 00 can correspond to an entry in the PL offset configuration list and can be recognized by the UE. On the other hand, when configuration cannot be performed using the PL offset configuration list received via RRC signaling, the value between the PL offset value indicated by PL offset configuration ID 00 and the PL offset value indicated by PL offset configuration ID 01 can be configured. Figure 17 The example illustrates the repeated application of such an operation. More specifically, the configuration of octets 3 through 5 can be a repetition of the configuration of octets 0 through 2. Figure 17 In the example, the TCI indicator and offset indicator can be omitted to reduce the number of bits.

[0579] Figure 18 This is a conceptual diagram illustrating the third PL offset MAC-CE configuration according to the seventh exemplary embodiment.

[0580] refer to Figure 18 MAC-CE can consist of an octet 0 (one byte), an octet 1 (one byte), and an octet 2 (one byte). In other words, MAC-CE can consist of a total of three octets (three bytes). The first bit of octet 0 can be configured as a reserved bit, the following five bits can be configured as the serving cell ID, and the last two bits can be configured as the BWP ID. The first bit of octet 1 can be configured as the TCI indicator, and the following seven bits can be configured as the joint / UL TCI status ID. The first bit of octet 2 can be configured as the offset indicator, the following four bits can be configured as the PL offset configuration ID, and the last three bits can be configured as the differential PL offset value.

[0581] like Figure 18 As shown, for each joint / UL TCI state, a MAC-CE can consist of a PL offset configuration ID and a differential PL offset value. Here, the differential PL offset value can correspond to the incremental PL value mentioned above, and to reduce the number of bits, the differential PL offset value can be configured as an incremental PL index indicating the incremental PL value, as shown in the reference. Figure 15 As stated above.

[0582] The TCI indicator can indicate whether the subsequent TCI status is the combined TCI status ID 0 or the UL TCI status ID 0.

[0583] The offset indicator can indicate whether configuration can be performed using a PL offset configuration list received via RRC signaling, or not. When configuration can be performed using a PL offset configuration list received via RRC signaling, the PL offset configuration ID can correspond to an entry in the PL offset configuration list and can be identified by the UE. On the other hand, when configuration cannot be performed using a PL offset configuration list received via RRC signaling, the PL offset value of the TCI state can be configured by combining the PL offset value indicated by the PL offset configuration ID with a differential PL offset value. Here, the differential PL offset value can indicate the difference between the PL offset value configured by a PL offset in the configuration list and the actual estimated (or obtained) PL offset value. However, this disclosure is not limited to this.

[0584] When the PL offset value is mapped to the initial value of the differential PL offset value or to the deactivated TCI state, the PL offset value can be 0 dB, as in the reference. Figure 15 As described in the incremental PL configuration at incremental PL index 0. Furthermore, to reduce the number of bits transmitted via MAC-CE, as mentioned above, the TCI indicator and offset indicator can be omitted.

[0585] Figure 19 This is a conceptual diagram illustrating the fourth PL offset MAC-CE configuration according to the seventh exemplary embodiment.

[0586] refer to Figure 19 A MAC-CE can be composed of an octet 0 (one byte), an octet 1 (one byte), an octet 2 (one byte), an octet 3 (one byte), an octet 4 (one byte), and an octet 5 (one byte). In other words, a MAC-CE can be composed of a total of six octets (six bytes).

[0587] The first bit of octet 0 can be configured as a reserved bit that is always set to 0, the following five bits can be configured as Serving Cell ID 0, and the last two bits can be configured as BWP ID 0. The first bit of octet 1 can be configured as the TCI indicator, and the following seven bits can be configured as the Joint / UL TCI Status ID 0. The first bit of octet 2 can be configured as the offset indicator, the following three bits can be configured as the PL Offset Configuration ID 00, the next three bits after PL Offset Configuration ID 00 can be configured as the Differential PL Offset Value, and the last bit can be configured as the Next Indicator 0. The first bit of octet 3 can be configured as a reserved bit, the following five bits can be configured as Serving Cell ID 1, and the last two bits can be configured as BWP ID 1. The first bit of octet 4 can be configured as the TCI indicator, and the following seven bits can be configured as the Joint / UL TCI Status ID 1. The first bit of octet 5 can be configured as an offset indicator, the next three bits can be configured as PL offset configuration ID 10, the next three bits after PL offset configuration ID 10 can be configured as the differential PL offset value, and the last bit can be configured as the next indicator 1.

[0588] like Figure 19 As shown, a MAC-CE can be configured with a PL offset configuration ID and a differential PL offset value for each joint / UL TCI state. Here, the differential PL offset value can correspond to the incremental PL value mentioned above. To reduce the number of bits sent through the MAC-CE, a method such as referenced... Figure 15 The description uses the incremental PL index, which indicates the incremental PL value, instead of the differential PL offset value.

[0589] The TCI indicator can indicate whether the subsequent TCI state is the joint TCI state ID 0 or the UL TCI state ID 0. The offset indicator can indicate whether configuration can be performed using the PL offset configuration list received via RRC signaling, or not. When configuration can be performed using the PL offset configuration list received via RRC signaling, PL offset configuration ID 00 can correspond to an entry in the PL offset configuration list and can be reconfigured by the UE. On the other hand, when configuration cannot be performed using the PL offset configuration list received via RRC signaling, the PL offset value of the corresponding TCI state can be configured by combining the PL offset value indicated by PL offset configuration ID 00 with the differential PL offset value 00. Here, the differential PL offset value 00 can indicate the difference between the PL offset value configured in the configuration list and the actual estimated (or obtained) PL offset value. However, this disclosure is not limited thereto.

[0590] When the PL offset value is mapped to the initial value of the differential PL offset value or to the deactivated TCI state, the PL offset value can be 0 dB, as in the reference. Figure 15 As described in the incremental PL configuration at incremental PL index 0. Furthermore, to reduce the number of bits transmitted via MAC-CE, as mentioned above, the TCI indicator and offset indicator can be omitted.

[0591] Figure 19 This can also be understood as repeatedly applying three octets. Here, when the PL offset value is mapped to the initial value of the differential PL offset value or mapped to the deactivated TCI state, the PL offset value can be 0 dB, as in the reference... Figure 15 As described in the incremental PL configuration at incremental PL index 0. Furthermore, to reduce the number of bits transmitted via MAC-CE, as mentioned above, the TCI indicator and offset indicator can be omitted.

[0592] In the eighth exemplary embodiment, it may be necessary to consider situations where the UE moves rapidly and therefore needs to be updated (e.g., high mobility situations), or situations where the PL offset information received via RRC signaling is inaccurate.

[0593] In this disclosure, a solution is described as follows for cases where the PL offset information received via RRC signaling is inaccurate: Figure 7a and Figure 7b The operation described above refers to the UE that has completed initial access to the first TRP (which is a macro TRP) within the BWP or CC. The UE that has completed initial access to the first TRP, which is a macro TRP, can receive a list of N PL offset configurations (or values) from the first TRP via RRC signaling. An example could be... Figure 15The PL offset configuration is shown. A UE that has received a list of N PL offset configurations from the first TRP via RRC signaling can store this list. Here, the UE can store the above via RRC signaling. Figure 15 The list of incremental PL configurations shown.

[0594] like Figure 15 As shown, the first TRP, which has estimated (or obtained) the PL offset value between the UE and the target UL-only TRP, can map a PL offset configuration (or value) in the PL offset configuration list to the joint / ULTCI state corresponding to each UL-only TRP, and can send the mapping information to the UE by configuring the mapping information in a DCI.

[0595] When the PL offset configuration (or value) in the above configuration list does not include the PL offset value estimated (or obtained) by the first TRP, needs to be updated based on the estimated PL offset value, or has low correlation with the estimated PL offset value, the first TRP (or network) may add one or more bits of information to the DCI to allow for its identification. The bits added to the DCI may configure the difference between a PL offset configuration (or value) in the PL offset configuration list corresponding to the joint / UL TCI state and the PL offset value estimated by the first TRP. In other words, an incremental PL value may be configured. In this case, an exemplary embodiment for selecting a PL offset configuration (or value) is to select the PL offset configuration (or value) that is closest to the PL offset value estimated by the first TRP.

[0596] Hereinafter, detailed exemplary embodiments of the eighth exemplary embodiment are described.

[0597] First, a first detailed exemplary embodiment of the eighth exemplary embodiment will be described.

[0598] The UE can receive the PL offset configuration list via RRC signaling. That is, the first TRP can send the PL offset configuration list to the UE via RRC signaling. The first TRP can include two PL offset configuration indices adjacent to the PL offset value to be applied to the UE in the DCI to be sent to the UE. Table 3 below can be an example of a DCI format used for PDCCH commands among various DCI formats.

[0599] [Table 3]

[0600]

[0601] As shown in Table 3, PL offset configuration index 1 and PL offset configuration index 2 can be assigned within the DCI field. A UE that has received a PDCCH command can send a PRACH preamble to the corresponding TRP by applying the PL offset value indicated by PL offset configuration index 1, by applying the PL offset value indicated by PL offset configuration index 2, or by applying the value between the PL offset values ​​indicated by PL offset configuration index 1 and PL offset configuration index 2. The identifier field for the DCI format can always have a value of 1 and can indicate the downlink. In Table 3, the bit values ​​of the frequency domain resource allocation field can all be set to 1, and the random access preamble index can indicate the index of the preamble used for random access. When the information value of this field is '0', the UL / SUL indicator can indicate UL, and when the information value of this field is '1', it can indicate SUL. When the bit values ​​of the random access preamble index are not all zero and the UE is configured with supplementaryUplink in the ServingCellConfig of the cell, the UL / SUL indicator can indicate the UL carrier of the cell used to transmit PRACH.

[0602] Furthermore, in Table 3, the SS / PBCH index can indicate the beam index of the Synchronization Signal Block (SSB), and the PRACH mask index can indicate the RO associated with the SS / PBCH indicated by the SS / PBCH index. It should be noted that Table 3 is an example of the DCI format used for the PDCCH command, and the PL offset configuration index 1 and PL offset configuration index 2 presented in Table 3 can be assigned to all other possible DCI formats.

[0603] In addition, instead of the SS / PBCH index in Table 3, beam indices, TRP indices, or combined / UL TCI states required for efficient system access can be assigned. Furthermore, only one PL offset configuration index can be configured. As an alternative method for delivering beam scanning instructions to the UE, when the first TRP instructs the UE to perform a beam scan using a PRACH preamble, the first TRP can send a DCI to the UE in the form of a PDCCH command to instruct beam scanning after the first TRP and the UE have completed RRC reconfiguration.

[0604] Next, a second detailed exemplary embodiment of the eighth exemplary embodiment will be described.

[0605] The UE can receive the PL offset configuration list via RRC signaling. That is, the first TRP can send the PL offset configuration list to the UE via RRC signaling. The first TRP can include a PL offset configuration index and a differential PL offset index (or value) adjacent to the PL offset value to be applied to the UE in the DCI to be sent to the UE, and can send the DCI to the UE. Table 4 below can be an example of a DCI format used for PDCCH commands among various DCI formats.

[0606] [Table 4]

[0607]

[0608] As shown in Table 4, the PL offset configuration index and differential PL offset index / value can be assigned within the DCI field. A UE that has received a PDCCH command can send a PRACH preamble to the corresponding TRP by applying the value obtained by combining (e.g., adding) the PL offset value indicated by the PL offset configuration index and the value indicated by the differential PL offset index / value. In Table 4, the identifier field for DCI format can always be set to 1 and can indicate the downlink. The bit values ​​of the frequency domain resource allocation field can all be set to 1. The random access preamble index field can indicate the index of the preamble used for random access. When the information value of this field is 0, the UL / SUL indicator can indicate UL, and when the information value of this field is 1, the UL / SUL indicator can indicate SUL. When the bit values ​​of the random access preamble index are not all zero and the UE is configured with supplementaryUplink in the ServingCellConfig of the cell, the UL / SUL indicator can indicate the UL carrier of the cell used to send PRACH.

[0609] In Table 4, the SS / PBCH index can indicate the beam index of the SSB. The PRACH mask index can indicate the RO associated with the SS / PBCH identified by the SS / PBCH index. Here, Table 4 is an example of the DCI format used for PDCCH commands, and the aforementioned PL offset configuration index and differential PL offset index / value can be assigned to all other possible DCI formats. Furthermore, instead of the SS / PBCH index in Table 4, the beam index and TRP index required for efficient system access can be assigned.

[0610] Next, a third detailed exemplary embodiment of the eighth exemplary embodiment will be described.

[0611] The UE can receive the PL offset configuration list via RRC signaling. That is, the first TRP can send the PL offset configuration list to the UE via RRC signaling. The first TRP can send the applicable PL offset configuration list from the PL offset configuration list sent to the UE via RRC signaling to the UE via MAC-CE. The MAC-CE can send the joint TCI status or UL TCI status associated with the PL offset configuration list sent to the UE via RRC signaling. The UE can receive the joint TCI status or UL TCI status associated with the PL offset configuration list via MAC-CE. When transmitting uplink signals (channels), the UE can identify the PL offset value and the associated joint TCI status or UL TCI status based on the MAC-CE received from the first TRP. Subsequently, the first TRP can indicate the joint TCI status or UL TCI status via the DCI sent to the UE.

[0612] Table 5 below shows an example of the configuration of the DCI format for PDCCH commands among the various DCI formats sent to the UE.

[0613] [Table 5]

[0614]

[0615] Table 5 provides an example of allocating a joint TCI state or UL TCI state within the DCI field. A UE that has received a PDCCH command as shown in Table 5 can send a PRACH preamble to the corresponding TRP by applying the PL offset value indicated by the joint TCI state or UL TCI state. In Table 5, the value of the identifier field for the DCI format can always be 1 and can indicate the downlink. The bit values ​​of the frequency domain resource allocation field can all be 1. The random access preamble index field can indicate the index of the preamble used for random access. When the information value of this field is 0, the UL / SUL indicator can indicate UL, and when the information value of this field is 1, the UL / SUL indicator can indicate SUL. When the bit values ​​of the random access preamble index are not all zero and the UE is configured with a supplementary uplink in the cell's ServingCellConfig, the UL / SUL indicator can indicate the UL carrier of the cell used to send the PRACH.

[0616] In Table 5, the SS / PBCH index can indicate the beam index of the SSB. The PRACH mask index can indicate the RO associated with the SS / PBCH identified by the SS / PBCH index. Here, Table 5 is an example of the DCI format for PDCCH commands, and the joint TCI state or UL TCI state described in Table 5 can be assigned to all other possible DCI formats. Furthermore, instead of the SS / PBCH index, the beam index and TRP index required for efficient system access can be assigned.

[0617] Next, a fourth detailed exemplary embodiment of the eighth exemplary embodiment will be described.

[0618] The UE can receive the PL offset configuration list, incremental PL value configuration list, and / or PL offset configuration list via RRC signaling. That is, the first TRP can send the PL offset configuration list, incremental PL value configuration list, and / or PL offset configuration list to the UE via RRC signaling. The first TRP can send a joint TCI status or UL TCI status to the UE via RRC signaling and / or MAC-CE. This joint TCI status or UL TCI status is associated with the UE-applicable PL offset configuration list, incremental PL value configuration list, and / or PL offset configuration list sent to the UE via RRC signaling. Therefore, the UE can receive the joint TCI status or UL TCI status associated with the PL offset configuration list, incremental PL value configuration list, and / or PL offset configuration list from the first TRP via RRC signaling and / or MAC-CE.

[0619] Subsequently, the first TRP can send a PDCCH command to the UE including additional fields. For example, the PDCCH command can be DCI format 1_0. The DCI format 1_0 for the PDCCH command, including additional fields, can also include one or more of the following: an Asym indicator, a combined TCI state / UL TCI state, a PL offset configuration index, and / or an incremental PL value index. In this case, the DCI field (or DCI format) can be present when the corresponding RRC parameter (e.g., a new RRC parameter whose configuration adds a 1-bit DCI field (e.g., the Asym indicator field)) is activated and at least one TCI state is configured as a PL offset.

[0620] Table 6 below shows an example of the configuration of the DCI format for PDCCH commands among the various DCI formats sent to the UE according to the fourth detailed exemplary embodiment of the eighth exemplary embodiment.

[0621] [Table 6]

[0622]

[0623] The UE that receives the PDCCH command shown in Table 6 can send the PRACH preamble to the UL-only TRP by applying the PL offset value indicated by the PL offset configuration index and the incremental PL value indicated by the incremental PL value index based on the joint TCI state / UL TCI state indicated by the PDCCH command format shown in Table 6.

[0624] In Table 6, the identifier field for DCI format can always be 1 and can indicate the downlink. The frequency domain resource allocation field can have all bits set to 1. The random access preamble index field indicates the index of the preamble used for random access. When this field's information value is 0, the UL / SUL indicator indicates UL; when the field's information value is 1, the UL / SUL indicator indicates SUL. When the random access preamble index bit values ​​are not all zero and the UE is configured with supplementary uplink in the cell's ServingCellConfig, the UL / SUL indicator indicates the UL carrier of the cell used to transmit PRACH.

[0625] In Table 6, the SS / PBCH index indicates the beam index of the SSB. The PRACH mask index indicates the RO associated with the SS / PBCH identified based on the SS / PBCH index. Furthermore, the Asym indicator field indicates whether the DCI format of the PDCCH command corresponds to an asymmetric mTRP scenario. For example, a bit value of '0' in the Asym indicator field indicates a symmetric mTRP scenario. When the bit value of the Asym indicator field indicates a symmetric mTRP scenario, subsequent consecutive fields, namely the combined TCI status / UL TCI status, PL offset configuration index, and incremental PL value index, can be ignored.

[0626] On the other hand, when the bit value of the Asym indicator field is '1', it can indicate an asymmetric mTRP scenario. As mentioned above, when the bit value of the Asym indicator field indicates an asymmetric mTRP scenario, the subsequent consecutive joint TCI status / ULTCI status fields can indicate the uplink transmission beam direction required when sending a PRACH preamble to the corresponding UL-only TRP. Furthermore, when the bit value of the Asym indicator field indicates an asymmetric mTRP scenario, the PL offset configuration index and / or incremental PL value index can respectively indicate the PL offset value and / or incremental PL value pre-received via MAC-CE or RRC signaling.

[0627] Here, to utilize resources efficiently, when the Asym indicator is 1, the UL / SUL indicator and / or SS / PBCH index and / or other existing fields (e.g., the 1-bit PRACH association indicator field newly added in the 3GPP Rel-18 specification) can be reused. When existing fields can be reused, all or some of the fields used for the asymmetric mTRP scenario in Table 6 can be allocated and used (e.g., the combined TCI status / UL TCI status and / or PL offset configuration index and / or incremental PL value index).

[0628] When existing fields can be reused but it is not possible to assign all fields for asymmetric mTRP scenarios, one or more fields from the combined TCI status / UL TCI status, PL offset configuration index, and incremental PL value index can be assigned to the UL / SUL indicator and SS / PBCH index fields.

[0629] In addition, one or more of the UL / SUL indicator, SS / PBCH index, or other existing fields (such as the PRACH associated indicator field) can be reused to allocate the PL offset configuration index (indicating the PL offset value) and / or the incremental PL value index.

[0630] In addition, one of the reasons for reusing existing fields or adding one or more of the joint TCI status / UL TCI status, PL offset configuration index, or incremental PL value index may be to clarify that the UL-only TRP indicated by the first TRP for UE access is not limited to a single UL-only TRP.

[0631] As an exemplary modification, in Table 6, only the Asym indicator and the combined TCI status / ULTCI status fields can be added, and the remaining PL offset configuration index and incremental PL value index can be excluded. As another exemplary modification, when the number of bits in the multiplexed fields in Table 6 is sufficient, only the Asym indicator field can be added, and the remaining combined TCI status / ULTCI status, PL offset configuration index, and incremental PL value index can be excluded.

[0632] When the Asym indicator field is 1, the UL / SUL indicator and SS / PBCH index fields can be reused, so that the combined TCI status / UL TCI status information is included in seven bits, the combined TCI status / UL TCI status and PL offset configuration index information can be included in seven bits, or the combined TCI status / UL TCI status, PL offset configuration index or incremental PL value index information can be included in seven bits.

[0633] An example of a modification to Table 6 can be shown in Table 7.

[0634] [Table 7]

[0635]

[0636] First, in Table 7, DCI format 1_0 can be used, further including the PRACH association indicator field. The DCI format of Table 7 can exist when the corresponding RRC parameter (i.e., the new RRC parameter, which configures the presence of a 1-bit Asym indicator field in the DCI format) is activated and at least one TCI state is configured as a PL offset. For example, when indicating a joint TCI state or UL TCI state according to the unified TCI framework of 3GPP Rel-17, a bit value of 0 in the Asym indicator field can indicate that the PL offset is not included in the PRACH transmit power calculation. On the other hand, a bit value of 1 in the Asym indicator field can indicate that the PL offset associated with the TCI state indicated from the RRC and / or MAC-CE message is included in the PRACH transmit power calculation.

[0637] As described above, when the Asym indicator field has a value of 1, it can indicate that the RACH preamble is sent to the ULTRP only. For example, by multiplexing one or more of the UL / SUL indicator, SS / PBCH index, PRACH association indicator, or other unused fields configured in DCI format, the first TRP can indicate to the UE one or more of the following: the transmit beam pointing in the direction where the ULTRP only exists, the joint TCI state corresponding to the transmit beam, the UL TCI state or unified TCI state, the PL offset obtained from the RRC or MAC-CE message, the incremental PL value index, the transmit power control (TPC) indicating the increment or decrement of transmit power when the transmitted PRACH preamble is retransmitted, or any other possible field information.

[0638] Here, when the value of the Asym indicator field is 1, after the UE initially establishes a connection with the first TRP, the first TRP can send the UE one or more of the following: beam direction, time / frequency resource information, or transmit power or transmit power adjustment information for the preamble sent to an unknown UL-only TRP, by using one or more bits of the multiplexed UL / SUL indicator, SS / PBCH index, PRACH association indicator, or other unused fields.

[0639] Additionally, when two joint TCI states or UL TCI states are indicated according to the unified TCI framework of 3GPP Rel-18 (i.e., when an RRC or MAC-CE parameter or message containing information about the indicated joint TCI state or UL TCI state associated with each PL offset is received), for the 1-bit Asym indicator field in DCI 1_0 indicating the PL offset of a PRACH transmission via a PDCCH command, bit field index 0 indicating the unified TCI can indicate that the PL offset associated with the first indicated joint TCI state or UL TCI state is included in the PRACH transmit power calculation. On the other hand, bit field index 1 indicating the unified TCI can indicate that the PL offset associated with the second indicated joint TCI state or UL TCI state is included in the PRACH transmit power calculation.

[0640] As described above, when the value of the field indicating the unified TCI is 0, it can indicate that the PRACH preamble is sent to the first UL-only TRP specified by the RRC or MAC-CE parameters or message. For example, one or more of the UL / SUL indicator, SS / PBCH index, PRACH association indicator, or other unused fields configured in DCI format can be multiplexed. When one or more fields are multiplexed, the first TRP can indicate to the UE one or more of the following: the transmit beam pointing in the direction where the UL-only TRP exists, the joint TCI state corresponding to the transmit beam, the UL TCI state or unified TCI state, the PL offset obtained from the RRC or MAC-CE message, the incremental PL value index, transmit power control (TPC) indicating the increment or decrement of transmit power when the transmitted PRACH preamble is retransmitted, or any other possible information.

[0641] On the other hand, when the value of the field indicating the unified TCI is 1, it can indicate that the PRACH preamble is sent to the second UL-only TRP specified by the RRC or MAC-CE parameters or messages. For example, one or more of the UL / SUL indicator, SS / PBCH index, PRACH association indicator, or other unused fields configured in DCI format can be multiplexed. When one or more fields are multiplexed, the first TRP can indicate to the UE one or more of the following: the transmit beam pointing in the direction where the UL-only TRP exists, the joint TCI state corresponding to the transmit beam, the UL TCI state or unified TCI state, the PL offset obtained from the RRC or MAC-CE message, the incremental PL value index, transmit power control (TPC) indicating the increment or decrement of transmit power when the transmitted PRACH preamble is retransmitted, or any other possible information.

[0642] Furthermore, when the Asym indicator field value is 0 or 1, the first TRP can send one or more of the following to the UE by using bits from one or more of the multiplexed UL / SUL indicator, SS / PBCH index, PRACH association indicator, or other unused fields: beam direction of the preamble to an unknown UL-only TRP, its time / frequency resource information, or transmit power or transmit power adjustment information. In this case, the UE can be in a state where an initial connection has been established with the first TRP.

[0643] Next, a fifth detailed exemplary embodiment of the eighth exemplary embodiment will be described.

[0644] As mentioned above Figure 15 As shown, the UE can receive a MAC-CE in which the association of the joint TCI state or UL TCI state mapped to the PL offset configuration list and / or incremental PL index (or value) list is updated. Thereafter, as shown in Table 8 below, the first TRP can be sent to the UE via the DCI used for the PDCCH command, along with the Asym mTRP indication. Figure 15 The same or similar combined TCI state or UL TCI state, scan or repetition count, RO configuration, etc., associated with PL offset and incremental PL are shown below. The DCI for PDCCH commands according to the fifth detailed exemplary embodiment of the eighth exemplary embodiment of this disclosure can be configured as shown in Table 8 below.

[0645] [Table 8]

[0646]

[0647] For example, the bits of the Asym mTRP indicator field can be configured as follows.

[0648] (1) When the bit information indicated by Asym mTRP is set to '00', the UE receiving the PDCCH command can transmit the preamble in the same manner as in the conventional case. More specifically, when the bit information indicated by Asym mTRP is set to '00', the UE can transmit the preamble at the given frequency position, that is, at the time / frequency position indicated by the PRACH RO index given in the frequency domain resource allocation field, as in the baseline PDCCH command preamble transmission example. Furthermore, the preamble can be configured based on the random access preamble index included in the PDCCH command. The direction of transmitting the preamble can be indicated by the SS / PBCH index included in the PDCCH command.

[0649] (2) When the bit information of the Asym mTRP indication included in the PDCCH command is set to '01', the UE can determine the initial UL TRP-only access state. Therefore, the UE can send a preamble to the UL TRP-only via a predetermined number of scans and / or repetitions (e.g., corresponding to the scan / repetition count field shown in Table 6 or Table 8). The transmission power of the beam through which the preamble is transmitted can be the transmission power determined during the initial system access process between the first TRP and the UE, or any arbitrary transmission power.

[0650] The transmission time of the beam through which the preamble is transmitted can correspond to one or more ROs in the PRACH ROs (e.g., the RO configuration field in Table 8) delivered to the UE by the first TRP via RRC and / or MAC-CE messages. Here, when multiple ROs are grouped, the RO configuration may not indicate a single RO, but rather a list of group configurations. The number of ROs in the group configuration list may correspond to the number indicated by the scan / repetition count field. Furthermore, the preamble transmitted via the beam can be a preamble generated based on the random access preamble index included in the PDCCH command as shown in Table 8.

[0651] Regarding the scanned and / or retransmitted preambles as described above, the UE does not set a RAR window timer for RAR reception. In other words, the UE may choose not to receive RAR, and the UE may choose not to perform preamble retransmission.

[0652] (3) When the bit information indicated by Asym mTRP included in the PDCCH command is set to '10', the UE receiving the PDCCH command can determine a non-initial system connection state. When the UE determines a non-initial system connection state, the UE can transmit a preamble in the direction indicated by the joint TCI state / UL TCI state received via MAC-CE or RRC messages. In this case, the transmission power of the preamble can be calculated using the UL PL calculated by Equation 2 and / or Equation 3 above.

[0653] The frequency position for transmitting the preamble can be determined based on the frequency domain resource allocation field, and the time resource can be determined using the PRACHRO index field. Furthermore, the preamble for transmission can be generated based on the random access preamble index. Therefore, the generated preamble can be transmitted to ULTRP-only within the time / frequency resources indicated by the PDCCH command in Table 8.

[0654] To reduce the number of bits in the PDCCH command DCI format as shown in Table 8 of the fifth detailed exemplary embodiment of the eighth exemplary embodiment described above, one or more of the scan / repetition count field and the RO configuration field may be omitted. When one or more of the two fields are omitted, the information of the omitted field can be defined as being sent to the UE via MAC-CE and / or RRC signaling.

[0655] Furthermore, when a new PDCCH command format for asymmetric mTRP mode is defined separately from the existing and / or baseline PDCCH command formats, the fields in the new DCI format may include an identifier field for the DCI format, a frequency domain resource allocation field, a random access preamble index field, a PRACH RO index field, a PCI index field, a 2-bit Asym mTRP indicator field (e.g., the bit information is set to '00' for initial access and '01' for non-initial access), a scan / repetition count field, a RO configuration field, a joint TCI status / UL TCI status field, and reserved bits, etc. Here, the bit '0' of the Asym mTRP indicator field may follow the description of '01' of the Asym mTRP indicator field in Table 8, and the bit '1' of the Asym mTRP indicator field may follow the description of '10' of the Asym mTRP indicator field in Table 8.

[0656] Next, a sixth detailed exemplary embodiment of the eighth exemplary embodiment will be described below.

[0657] As mentioned above Figure 15 As shown, the UE can receive a MAC-CE to update the association of the joint TCI state / UL TCI state mapped to the PL offset configuration list and / or the incremental PL index / value list. Based on the received MAC-CE, the UE can instruct and / or activate the association of the joint TCI state / UL TCI state mapped to the PL offset configuration list and / or the incremental PL index / value list.

[0658] Subsequently, as shown in Table 9, the first TRP can send an Asym mTRP indication, scan / repetition count, RO configuration, etc., to the UE via the DCI used for PDCCH commands. The DCI used for PDCCH commands according to the sixth detailed exemplary embodiment of the eighth exemplary embodiment of this disclosure can be configured as shown in Table 9 below.

[0659] [Table 9]

[0660]

[0661] For example, the bits of the Asym mTRP indication field can be configured as follows: (1) When the bits of the Asym mTRP indication are set to '00', the UE receiving the PDCCH command can send the preamble in the same manner as in the conventional case. More specifically, when the bits of the Asym mTRP indication are set to '00', the UE can send the preamble at the time / frequency position indicated by the PRACH RO index given in the frequency domain resource allocation field, as in the baseline PDCCH command preamble transmission example. In addition, the preamble can be configured based on the random access preamble index included in the PDCCH command. The direction of sending the preamble can be the direction indicated by the SS / PBCH index included in the PDCCH command.

[0662] (2) When the bit information of the Asym mTRP indication included in the PDCCH command is set to '01', the UE can determine the initial UL TRP-only access state. Therefore, the UE can send a preamble to the UL TRP-only via a predetermined number of scans and / or repetitions (e.g., corresponding to the scan / repetition count field shown in Table 6 or Table 8). The transmission power of the beam through which the preamble is transmitted can be the transmission power determined during the initial system access process between the first TRP and the UE, or any arbitrary transmission power.

[0663] The transmission time of the beam through which the preamble is transmitted can correspond to one or more ROs among those delivered to the UE by the first TRP via RRC and / or MAC-CE messages (e.g., the RO configuration field in Table 9). Here, when multiple ROs are grouped, the RO configuration may not indicate a single RO, but rather a list of group configurations. The number of ROs in the group configuration list may correspond to the number indicated by the scan / repetition count field. Furthermore, the preamble transmitted via the beam can be a preamble generated based on the random access preamble index included in the PDCCH command as shown in Table 9.

[0664] Regarding the scanned and / or retransmitted preambles as described above, the UE does not set a RAR window timer for RAR reception. In other words, the UE may choose not to receive RAR, and the UE may choose not to perform preamble retransmission.

[0665] (3) When the bit information indicated by Asym mTRP included in the PDCCH command is set to '10', the UE receiving the PDCCH command can determine a non-initial system connection state. When the UE determines a non-initial system connection state, the UE can transmit a preamble in the direction indicated by the joint TCI state / UL TCI state received via MAC-CE or RRC messages. In this case, the transmission power of the preamble can be calculated using the UL PL calculated by Equation 2 and / or Equation 3 above.

[0666] The frequency position for transmitting the preamble can be determined based on the frequency domain resource allocation field, and the time resource can be determined using the PRACHRO index field. Furthermore, the preamble for transmission can be generated based on the random access preamble index. Therefore, the generated preamble can be transmitted to ULTRP-only within the time / frequency resources indicated by the PDCCH command in Table 9.

[0667] To reduce the number of bits in the PDCCH command DCI format exemplified in Table 9 of the sixth detailed exemplary embodiment of the eighth exemplary embodiment described above, one or more of the scan / repetition count field and the RO configuration field may be omitted. When one or more of the two fields are omitted, the information of the omitted field can be defined as being sent to the UE via MAC-CE and / or RRC signaling.

[0668] Furthermore, when a new PDCCH command format for asymmetric mTRP mode is defined separately from the existing and / or baseline PDCCH command formats, the fields in the new DCI format may include an identifier field for the DCI format, a frequency domain resource allocation field, a random access preamble index field, a PRACH RO index field, a 2-bit Asym mTRP indicator field (e.g., the bit information is set to '00' for initial access and '01' for non-initial access), an RO configuration field, a joint TCI status / UL TCI status field, and reserved bits, etc. Here, the bit '0' of the Asym mTRP indicator field may follow the description of '01' of the Asym mTRP indicator field in Table 8, and the bit '1' of the Asym mTRP indicator field may follow the description of '10' of the Asym mTRP indicator field in Table 8.

[0669] Next, a seventh detailed exemplary embodiment of the eighth exemplary embodiment will be described below.

[0670] As mentioned above Figure 15 As shown, the UE can receive MAC-CE to update the association of the joint TCI state / UL TCI state mapped to the PL offset configuration list and / or incremental PL index / value list.

[0671] Subsequently, as shown in Table 9, the first TRP can send the following to the UE: (The text abruptly ends here, so the translation stops as well.) Figure 15 The combined TCI / UL TCI states shown are associated with the PL offset and incremental PL. The information included in the UCI format for scheduling SRS signals and / or PUSCH / PUCCH channels can be configured as shown in Table 10 below.

[0672] [Table 10]

[0673]

[0674] A UE receiving the UCI as illustrated in Table 10 can transmit SRS, PUSCH, and / or PUCCH in the direction indicated by the joint TCI status / UL TCI status field. Furthermore, the UE can calculate the transmission power of SRS, PUSCH, and / or PUCCH using the PL offset configuration list and incremental PL index / value received via the aforementioned MAC-CE and / or RRC signaling, and the UL PL calculated using Equations 2 and / or 3 above. The UE can transmit SRS, PUSCH, and / or PUCCH at the frequency location configured by the frequency domain resource allocation information and at the scheduled time / frequency resource location. The aforementioned PL offset, TT offset, and mapping information between the UL TCI status / spatial relationship and the PL offset can be sent from the first TRP to the UE via RRC signaling, depending on the UE's mobility, or via a new or multiplexed MAC-CE.

[0675] When the UE moves slowly, the mapping information can be delivered to the UE in the form of a UL TCI status information element (IE) for each UL TRP only, via RRC signaling, within the RRC data of the PDSCH indicated by the DCI via the UE's UE-specific search space (USS).

[0676] On the other hand, when the UE moves rapidly, RRC signaling can be used. However, to reduce latency, the mapping information between PL offset, TT offset, and UL TCI state / spatial relationship and PL offset can be delivered to the UE as a field defined in the MAC-CE, instead of being delivered by the DCI via the PDSCH RRC data indicated by the UE's USS. In this case, the applied MAC-CE can reuse the MAC-CE defined in the current 5G NR specification, can be modified or extended, or a MAC-CE newly defined as 'asymmetric mTRP MAC-CE' can be used.

[0677] When using absolute TA instead of TT offset, the TAC MAC-CE corresponding to each UL TRP only can be reused. However, when using the newly defined asymmetric mTRP MAC-CE, the newly defined asymmetric mTRP MAC-CE can include PL offset, TT offset (or absolute TA), and mapping information between UL TCI state / spatial relationship and PL offset or TT offset, or all other possible information required.

[0678] By using the above method, asymmetric mTRP scenarios can be processed quickly, and the number of bits used can be reduced when sending TT offset to the UE instead of sending absolute TA.

[0679] When the above information is delivered to the UE via RRC signaling in the form of a UL TCI state IE for each UL TRP only, the UL TCI state IE can reflect the PL offset, TT offset (or absolute TA), and the mapping information between the UL TCI state / spatial relationship and the PL offset in the form of elements.

[0680] When the above information is sent to the UE via RRC signaling in the form of a UL TCI state IE for each UL TRP only, the UL TCI state IE can reflect the TT offset (or absolute TA) by extending the TAG ID concept that was previously reflected in the UL TCI state IE in the mapping information between PL offset, TT offset (or absolute TA) and UL TCI state / spatial relationship and PL offset.

[0681] In addition to the methods described above, all possible scalable methods (e.g., increasing the number of TAG IDs beyond the current value of 2 and mapping them to absolute TA values ​​defined by the TAG IDs) can also be understood in the same or similar manner as this disclosure. Therefore, the same or similar manner of the methods described in this disclosure can be included within the scope of this disclosure.

[0682] Figure 20 This is a conceptual diagram illustrating uplink communication between the UE and a UL-only TRP in an asymmetric mTRP environment.

[0683] refer to Figure 20 Base station 2041 can communicate with UE 2011 located in the cell of the base station using multiple TRPs 2001, 2002, and 2003. Figure 20 In the example, only three TRPs 2001, 2002 and 2003 are shown for the sake of simplicity. However, the number of TRPs that can be included in base station 2041 is not limited to three and can be more than three or less than three.

[0684] also, Figure 20 The exemplary embodiment assumes that three different TRPs are included in a base station 2041, wherein the first TRP 2001 may have a first cell area 1110, the second TRP 2002 may have a second cell area 2020, and the third TRP 2003 may have a third cell area 2030. Figure 20 The first TRP 2001 shown can be referred to as the macro TRP or header TRP described above, and can perform DL and UL communication with UE 2011. The second TRP 2002 and the third TRP 2003 can be the UL-only TRPs described above. Therefore, the second TRP 2002 and the third TRP 2003 can be TRPs that do not transmit any downlink signals, or they can be TRPs that transmit only minimal downlink signals.

[0685] Figure 20 The UE 2011 shown can correspond to Figure 10a and Figure 10b The UE #0 described herein can be in an RRC connection state with the first TRP 2001. In other words, in Figure 20 In the middle, UE 2011 can be in a state where it has already been executed using the first TRP2001. Figures 10a to 10b The states of steps S1000 and S1021 to S1023 described in the text. Additionally, in... Figure 20 In UE2011, it can be in a state where it has already been executed. Figures 10a to 10b The states of steps S1030, S1040, S1051, S1052, and S1060 described above. Since specific exemplary embodiments or modified exemplary embodiments of steps S1030, S1040, S1051, S1052, and S1060 have already been described above, redundant descriptions are omitted.

[0686] Figure 20 This schematically illustrates the execution of UE 2011. Figure 10bThe cases described in steps S1071 and S1072 are as follows. UE2011 can perform UL communication with only UL TRPs 2002 and 2003 by using the PL offset, TT offset (or absolute TA) received from the first TRP 2001, and the mapping information between the UL TCI state or spatial relationship and the PL offset or TT offset. More specifically, as shown by reference numeral 2051, UE2011 can perform UL transmission to the second TRP 2002. In this case, as described above, the first TRP can configure the beam direction, beam power, and resources (frequency resources and / or time resources) for UL transmission to the second TRP 2002. Furthermore, as shown by reference numeral 2052, UE2011 can perform UL transmission to the third TRP 2003. Again, in this case, as described above, the first TRP can configure the beam direction, beam power, and resources (i.e., frequency resources and / or time resources) for UL transmission to the third TRP 2003. Figure 20 This assumes the scenario of performing UL transmissions for two different ULTRPs only. However, this disclosure is not limited to this. For example, UE 2011 may perform UL transmissions for only one ULTRP only, or it may perform UL transmissions for three or more ULTRPs only. Furthermore, although in Figure 20 The UL transmission for the first TRP 2001 is not shown, but the UE 2011 may perform the UL transmission for the first TRP 2001 if necessary.

[0687] Additionally, when UE 2011 performs UL communications 2051 and 2052, the PL offset and TA can be updated. For example, the method for updating the PL offset and TA of UE 2011 can be performed as follows.

[0688] In the state where uplink transmission is performed only by the UL TRP (i.e., in the state where UE 2011 is served), UE 2011 can obtain the TA value for the UL TRP only through two TA procedures based on a single DCI. Thereafter, UE 2011 can perform beam management using the UL TRP only by employing SRS. As described above, such beam management can be performed at the first TRP 2001 for the UL TRP only by receiving the SRS transmitted by the UL TRP only and providing the measurement information of the received SRS to the first TRP (or base station or network). The first TRP 2001 can transmit uplink beam direction information and / or uplink beam power information to UE 2011. In this case, the uplink beam direction information and / or uplink beam power information can be beam direction information and / or beam power information for the UL TRP only.

[0689] On the other hand, when UE 2011 has high mobility, the first TRP 2001 can send the increme...

Claims

1. A method for a user equipment (UE), comprising: While in a Radio Resource Control (RRC) connection state with a first Transmitting and Receiving Point (TRP), a first message is received from the first TRP, the first message indicating the transmission of a first uplink (UL) signal to the first TRP or to a second TRP; Generate a first UL signal based on the received first message; as well as Based on the first message instruction, the generated first UL signal is sent to the second TRP. The second TRP is a TRP controlled by the first TRP.

2. The method according to claim 1, wherein, The first UL signal is a random access (RA) preamble transmitted via the Physical Random Access Channel (PRACH).

3. The method according to claim 1, wherein, The first message is downlink control information (DCI) for physical downlink control channel (PDCCH) commands, and the DCI includes a first field indicating whether path loss (PL) offset is used when determining the transmit power of the first UL signal, and indicating information related to the PL offset.

4. The method according to claim 3, wherein, The first field exists when a first parameter included in an RRC message received from the first TRP indicates activation of the first field, and when the RRC message is configured with one or more indicated Transport Configuration Indication (TCI) states corresponding to the PL offset.

5. The method according to claim 3, wherein, When the first parameter of an RRC message received from the first TRP before receiving the first message indicates activation of the first field included in the DCI, and the TCI configured in the RRC message or in a Media Access Control-Control Element (MAC-CE) message received from the first TRP before receiving the first message indicates a combined / UL TCI state corresponding to the PL offset, the first field indicates whether the PL offset corresponding to the combined / UL TCI state is used when determining the transmit power of the first UL signal sent to the second TRP.

6. The method according to claim 3, further comprising: Before receiving the first message, receive an RRC message or a MAC-CE message from the first TRP. Wherein, when the TCI configured in the RRC message or the MAC-CE message indicates two combined / UL TCI states corresponding to the PL offset, the first field indicates that when determining the transmission power of the second UL signal sent to the second TRP, the PL offset corresponding to one of the indicated combined / UL TCI states is used.

7. The method according to claim 3, wherein, When the first parameter of the RRC message received from the first TRP prior to receiving the first message indicates activation of the first field included in the DCI, and the RRC message configures two indicated joint / UL TCI states for the serving cell along with the PL offset, the first field indicates that one of the two joint / UL TCI states is used to transmit the first UL signal.

8. The method according to claim 3, wherein, When the first field indicates that the PL offset is applied to a TCI state or UL TCI state indicated by a higher layer, the first PL offset applied to determine the transmit power of the first UL signal is based on the difference between the path loss (PL) associated with the transmission of the first UL signal in the active downlink (DL) bandwidth portion (BWP) from the first TRP and the PL offset.

9. A method for a first transmitting and receiving point (TRP), comprising: Send a first message to a user equipment (UE) in a radio resource control (RRC) connection state, the first message indicating to send a first uplink (UL) signal to one or more second TRPs; Receive first information related to the first message from the one or more second TRPs; as well as Based on the first information, a second message is sent, the second message instructing the transmission of a second UL signal to the one or more second TRPs. Wherein, the one or more second TRPs are TRPs controlled by the first TRP.

10. The method according to claim 9, wherein, The first UL signal is a random access (RA) preamble transmitted via the Physical Random Access Channel (PRACH).

11. The method according to claim 9, wherein, The first message is downlink control information (DCI) for physical downlink control channel (PDCCH) commands, and the DCI includes a first field indicating whether path loss (PL) offset is used when determining the transmit power of the first UL signal, and indicating information related to the PL offset.

12. The method of claim 11, further comprising: Before sending the first message, an RRC message is sent to the UE. The first field is included in the DCI when the first parameter included in the RRC message indicates that the first field is activated, and when one or more indicated Transport Configuration Indication (TCI) states corresponding to the PL offset are configured in the RRC message.

13. The method of claim 11, further comprising: Before sending the first message, an RRC message or a Media Access Control-Control Element (MAC-CE) message is sent to the UE. Wherein, when the TCI configured in the RRC message or the MAC-CE message indicates two combined / UL TCI states corresponding to the PL offset, the first field indicates that when determining the transmission power of the second UL signal sent to the second TRP, the PL offset corresponding to one of the indicated combined / UL TCI states is used.

14. The method of claim 11, further comprising: Before sending the first message, an RRC message and a MAC-CE message are sent to the UE. Specifically, when the first parameter of the RRC message indicates activation of the first field included in the DCI, and the TCI configured in the RRC message or the MAC-CE message received before receiving the first message indicates a combined / UL TCI state corresponding to the PL offset, the first field indicates whether the PL offset corresponding to the combined / UL TCI state is used when determining the transmission power of the first UL signal sent to the second TRP.

15. The method of claim 11, further comprising: Before sending the first message, an RRC message is sent to the UE. Specifically, when the first parameter of the RRC message indicates activation of the first field included in the DCI, and the RRC message configures two indicated joint / UL TCI states for the serving cell along with the PL offset, the first field indicates that one of the two joint / UL TCI states is used to transmit the first UL signal.

16. The method according to claim 11, wherein, When the first field indicates that the PL offset is applied to a TCI state or UL TCI state indicated by a higher layer, the first PL offset applied to determine the transmit power of the first UL signal is based on the difference between the path loss (PL) associated with the transmission of the first UL signal in the active downlink (DL) bandwidth portion (BWP) from the first TRP and the PL offset.

17. A user equipment (UE) including at least one processor, wherein, The at least one processor causes the UE to perform: While in a Radio Resource Control (RRC) connection state with a first Transmitting and Receiving Point (TRP), a first message is received from the first TRP, the first message indicating the transmission of a first uplink (UL) signal to the first TRP or to a second TRP; Generate a first UL signal based on the received first message; as well as Based on the first message instruction, the generated first UL signal is sent to the second TRP. The second TRP is a TRP controlled by the first TRP.

18. The UE according to claim 17, wherein, The first UL signal is a random access (RA) preamble transmitted via the Physical Random Access Channel (PRACH).

19. The UE according to claim 17, wherein, The first message is downlink control information (DCI) for physical downlink control channel (PDCCH) commands, and the DCI includes a first field indicating whether path loss (PL) offset is used when determining the transmit power of the first UL signal, and indicating information related to the PL offset.

20. The UE according to claim 19, wherein, The first field exists when a first parameter included in an RRC message received from the first TRP indicates activation of the first field, and when the RRC message is configured with one or more indicated Transport Configuration Indication (TCI) states corresponding to the PL offset.

Images