Method and apparatus for beam management in a communication system

Abstract

An operation method of a first communication node may comprise the steps of: receiving information of one or more candidate beams of each of a first transmission and reception point (TRP) and a second TRP from the first TRP and the second TRP; transmitting information of one or more candidate beams of the second TRP to the first TRP; transmitting information of one or more candidate beams of the first TRP to a second TRP; receiving information of one or more beam combinations from the first TRP; transmitting, to the first TRP, information on a first measurement value for each beam combination corresponding to each of the one or more beam combinations; and receiving information of a first beam combination selected in the first TRP based on the transmitted information related to the first measurement value of each beam combination.

Description

Technical Field

[0001] The present invention relates to a beam management technology in a communication system, and more particularly to a beam management technology for beam-based communication between one or more base stations and one or more terminals in a communication system. Background Art

[0002] With the development of information and communication technology, various wireless communication technologies are being developed. Representative wireless communication technologies include long-term evolution (LTE) and new radio (NR) defined as the third generation partnership project (3GPP) standard. LTE may be one of the fourth generation (4G) wireless communication technologies, and NR may be one of the fifth generation (5G) wireless communication technologies.

[0003] In order to handle the rapidly growing wireless data, 5G NR communication or subsequent wireless communication technologies may support relatively high frequency band communications. For example, the radio frequency bands used for wireless communication may be roughly divided into frequency range 1 (FR1) and frequency range 2 (FR2). Here, the FR1 band may refer to a relatively low frequency band below about 7 GHz. The FR2 band may refer to a relatively high frequency band above about 7 GHz.

[0004] In relatively high frequency bands, such as the 24-53 GHz band (corresponding to the FR2 band), unlicensed bands, and millimeter wave bands, relatively high levels of path loss may occur. In an exemplary embodiment of a communication system utilizing high frequency bands, the path loss problem can be solved by utilizing a large number of antennas to send and receive wireless signals (or beams) with high antenna gain.

[0005] In an exemplary embodiment of a communication system, the network may include one or more base stations or one or more transmission and reception points (TRPs). In particular, a communication environment in which multiple TRPs exist may be referred to as "multi-TRP (MTRP)". Multiple TRPs may support the same terminal. If each of the multiple TRPs independently performs a beam management process for beam-based communication with the terminal, the beam selected by each TRP may not ensure that it is the best beam from the perspective of the terminal that receives beams from multiple TRPs at the same time. In addition, the beam of one TRP may strongly interfere with the beams of other TRPs, resulting in beam failure. When a terminal performs a beam management process with multiple TRPs in an MTRP environment, a joint beam management process may be required that takes into account the impact of a beam of one TRP on beams formed by other TRPs.

[0006] Matters described as related art are prepared to facilitate understanding of the background of the present invention and may include matters that are unknown to one of ordinary skill in the technical field to which exemplary embodiments of the present invention pertain. Summary of the invention

[0007] Technical issues

[0008] The present invention provides a method and apparatus for signal transmission and reception, which enhances beam transmission and reception performance based on multi-input multi-output (MIMO) technology, in which a large number of antennas are used to transmit and receive radio signals in a high frequency band.

[0009] Technical Solution

[0010] An operation method of a first communication node in a communication system according to a first exemplary embodiment of the present invention may include: receiving information of one or more candidate beams of each of a first transmitting and receiving point (TRP) and a second TRP; sending information of one or more candidate beams of the second TRP to the first TRP; sending information of one or more candidate beams of the first TRP to the second TRP; receiving information of one or more beam combinations from the first TRP; sending information of a first measurement value of each beam combination corresponding to each of the one or more beam combinations to the first TRP; and receiving information of a first beam combination selected based on information related to the first measurement value of each beam combination from the first TRP, wherein each of the one or more beam combinations can be configured as a combination of one beam of one or more candidate beams of the first TRP and one beam of one or more candidate beams of the second TRP.

[0011] Sending information about the first measurement value of each beam combination may include: receiving a first signal sent from a first TRP and a second TRP, the first signal corresponding to each of one or more beam combinations; performing a measurement operation on the received first signal; and sending information related to the first measurement value of each beam combination obtained at least based on the measurement operation to the first TRP, wherein, when receiving the first signal, a reception time of the first signal sent from the first TRP and a reception time of the first signal sent from the second TRP may be the same as each other.

[0012] When receiving a first signal, the first signal sent from the first TRP can be received based on a first time period configured according to information of one or more candidate beams of the first TRP, and the second signal sent from the second TRP can be received based on a second time period configured according to information of one or more candidate beams of the second TRP.

[0013] Sending information about the first measurement value of each beam combination may include: receiving information about a first threshold corresponding to the first measurement value from the second TRP; and sending information about the first threshold received from the second TRP and information about the first measurement value of each beam combination to the first TRP.

[0014] The first measurement value may be a signal to interference plus noise ratio (SINR) value of the first signal, and sending information about the first measurement value of each beam combination may include: receiving the first signal sent from the first TRP through a first panel corresponding to the first TRP in the first communication node; receiving the first signal sent from the second TRP through a second panel corresponding to the second TRP in the first communication node; obtaining a first measurement value for each of the received first signals; mapping the obtained first measurement value to each of one or more beam combinations to obtain information about the first measurement value of each beam combination; and sending at least information about the first measurement value of each beam combination to the first TRP.

[0015] The operating method may further include: before receiving information of one or more candidate beams of each of the first TRP and the second TRP, receiving information related to the transmission time of the first signal of the first TRP from the first TRP; and sending information related to the transmission time of the first signal of the first TRP to the second TRP.

[0016] The operating method may further include: before receiving information of one or more beam combinations, sending information of one or more candidate beams of the first communication node to the first TRP, wherein the first beam combination selected by the first TRP may include a first beam among the one or more candidate beams of the first TRP, a second beam among the one or more candidate beams of the second TRP, and a third beam among the one or more candidate beams of the first communication node.

[0017] The operating method may further include: before receiving information of one or more beam combinations, sending information of one or more candidate beams of the first communication node to the first TRP, wherein the first beam combination selected by the first TRP may include at least a first beam from the one or more candidate beams of the first TRP, a second beam from the one or more candidate beams of the second TRP, and a third beam corresponding to the first TRP and a fourth beam corresponding to the second TRP from the one or more candidate beams of the first communication node.

[0018] The operating method may further include: after receiving the information of the first beam combination, sending the received information of the first beam combination to the second TRP.

[0019] An operating method of a first transmitting and receiving point (TRP) in a communication system according to a second exemplary embodiment of the present invention may include: configuring one or more candidate beams of a first TRP; sending information of one or more candidate beams of the first TRP to a first communication node; receiving information of one or more candidate beams of a second TRP from the first communication node; configuring one or more beam combinations; sending information of one or more beam combinations to the first communication node; receiving information related to one or more first measurement values ​​of one or more first signals respectively corresponding to the one or more beam combinations from the first communication node; selecting a first beam combination from the one or more beam combinations based on the information related to the one or more first measurement values; and sending information of the selected first beam combination to the first communication node, wherein each of the one or more beam combinations may be configured as a combination of one beam of the one or more candidate beams of the first TRP and one of the one or more candidate beams of the second TRP.

[0020] The operating method may further include: before sending information about one or more candidate beams, sending information related to the transmission time of one or more first signals of the first TRP to the first communication node.

[0021] The operating method may further include: before configuring one or more beam combinations, sending information about the transmission time of one or more first signals sent from the first TRP to the first communication node, and the information about the transmission time is used to adjust the transmission time of one or more first signals sent from the second TRP.

[0022] The first measurement value may be a signal to interference plus noise ratio (SINR) value of the first signal, information related to one or more first measurement values ​​may include information of a first threshold corresponding to the one or more first measurement values ​​and information of the first measurement value of each beam combination, and selecting the first beam combination may include: identifying information of a second threshold corresponding to the one or more first measurement values ​​predetermined by the first TRP; and selecting the first beam combination from one or more beam combinations based on information of the first threshold, information of the second threshold, and information of the first measurement value of each beam combination.

[0023] The operating method may further include: before sending information of one or more beam combinations, receiving information of one or more candidate beams of the first communication node from the first communication node, wherein the first beam combination may include a first beam among the one or more candidate beams of the first TRP, a second beam among the one or more candidate beams of the second TRP, and a third beam among the one or more candidate beams of the first communication node.

[0024] The operating method may further include: before sending information of one or more beam combinations, receiving information of one or more candidate beams of the first communication node from the first communication node, wherein the first beam combination may include a first beam from one or more candidate beams of the first TRP, a second beam from one or more candidate beams of the second TRP, and a third beam corresponding to the first TRP and a fourth beam corresponding to the second TRP from one or more candidate beams of the first communication node.

[0025] According to the third exemplary embodiment of the present invention, a first communication node in a communication system may include at least one processor, wherein the at least one processor may enable the first communication node to execute: receiving information of one or more candidate beams of each of the first transmitting and receiving point (TRP) and the second TRP; sending information of one or more candidate beams of the second TRP to the first TRP; sending information of one or more candidate beams of the first TRP to the second TRP; receiving information of one or more beam combinations from the first TRP; sending information about a first measurement value of each beam combination corresponding to each of the one or more beam combinations to the first TRP; and receiving information of a first beam combination selected based on information related to the first measurement value of each beam combination from the first TRP, wherein each of the one or more beam combinations can be configured as a combination of one beam of one or more candidate beams of the first TRP and one beam of one or more candidate beams of the second TRP.

[0026] When sending information about a first measurement value of each beam combination, at least one processor may cause the first communication node to: receive a first signal sent from a first TRP and a second TRP, the first signal corresponding to each of one or more beam combinations; perform a measurement operation on the received first signal; and send information related to the first measurement value of each beam combination obtained at least based on the measurement operation to the first TRP, wherein, when receiving the first signal, a reception time of the first signal sent from the first TRP and a reception time of the first signal sent from the second TRP may be the same as each other.

[0027] When sending information about the first measurement value of each beam combination, at least one processor can cause the first communication node to perform: receiving information about a first threshold corresponding to the first measurement value from the second TRP; and sending information about the first threshold received from the second TRP and information about the first measurement value of each beam combination to the first TRP.

[0028] The first measurement value may be a signal to interference plus noise ratio (SINR) value of the first signal, and when sending information about the first measurement value of each beam combination, at least one processor may cause the first communication node to perform: receiving the first signal sent from the first TRP through a first panel corresponding to the first TRP in the first communication node; receiving the first signal sent from the second TRP through a second panel corresponding to the second TRP in the first communication node; obtaining a first measurement value for each of the received first signals; mapping the obtained first measurement value to each of one or more beam combinations to obtain information about the first measurement value of each beam combination; and sending at least information about the first measurement value of each beam combination to the first TRP.

[0029] At least one processor may further cause the first communication node to perform: before receiving information of one or more candidate beams of each of the first TRP and the second TRP, receiving information related to the transmission time of the first signal of the first TRP from the first TRP; and sending information related to the transmission time of the first signal of the first TRP to the second TRP.

[0030] Beneficial Effects

[0031] According to an exemplary embodiment of a beam management method and apparatus in a communication system, a beam combination for communication between a terminal and multiple TRPs can be determined based on a signaling process between the terminal and the multiple TRPs. Information about candidate beams (or beam candidate groups) for each TRP can be sent and received between the terminal and the multiple TRPs. Thus, one or more beam combinations can be determined. Among the one or more beam combinations thus determined, a beam combination can be selected based on a measurement result at the terminal. In the above manner, a beam adjustment process for communication between a terminal and multiple TRPs can be facilitated. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 is a conceptual diagram illustrating an exemplary embodiment of a communication system.

[0033] Figure 2 is a block diagram illustrating an exemplary embodiment of communication nodes constituting a communication system.

[0034] Figure 3 is a sequence diagram describing a first exemplary embodiment of a beam management method in a communication system.

[0035] Figure 4 is a sequence diagram describing a second exemplary embodiment of a beam management method in a communication system.

[0036] Figure 5 is a sequence diagram for describing a third exemplary embodiment of a beam management method in a communication system.

[0037] Figure 6a and Figure 6b is a sequence diagram for describing a fourth exemplary embodiment and a fifth exemplary embodiment of a beam management method in a communication system.

[0038] Figure 7a and Figure 7b is a sequence diagram for describing the sixth exemplary embodiment and the seventh exemplary embodiment of the beam management method in the communication system.

[0039] Figure 8 is a flow chart for describing an eighth implementation of a beam management method in a communication system.

[0040] Figure 9a and Figure 9b is a sequence diagram for describing the ninth exemplary embodiment and the tenth exemplary embodiment of the beam management method in the communication system.

[0041] Fig.10a and Fig.10b is a sequence diagram for describing an eleventh exemplary embodiment and a twelfth exemplary embodiment of a beam management method in a communication system.

[0042] Fig.11 is a sequence diagram for describing a first exemplary embodiment of a beam adjustment method in a communication system.

[0043] Fig.12 is a sequence diagram for describing a second exemplary embodiment of a beam adjustment method in a communication system.

[0044] Fig.13 is a flow chart for describing a first exemplary embodiment of a beam adjustment method in a communication system.

[0045] Fig.14 is a flow chart for describing a second exemplary embodiment of a beam adjustment method in a communication system. DETAILED DESCRIPTION

[0046] Exemplary embodiments of the present invention are disclosed herein. However, the specific structural and functional details disclosed herein are merely representative for the purpose of describing exemplary embodiments of the present invention. Therefore, exemplary embodiments of the present invention may be implemented in many alternative forms and should not be construed as being limited to the exemplary embodiments of the present invention set forth herein.

[0047] Therefore, although the present invention is capable of various modifications and alternative forms, specific exemplary 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 it is not intended to limit the present invention to the specific forms disclosed, but on the contrary, the present invention covers all modifications, equivalent forms and alternative forms that fall within the spirit and scope of the present invention. Throughout the description of the figures, the same reference numerals refer to the same elements.

[0048] It will be understood that, although the terms first, second, etc. can be used herein to describe each element, these elements should not be limited by these terms. These terms are only used to distinguish one element from another element. For example, without departing from the scope of the present invention, the first element can be referred to as the second element and similarly, the second element can be referred to as the first element. As used in this article, the term "and / or" includes any combination and all combinations of one or more related enumeration items.

[0049] It will be understood that when an element is referred to as being "connected" or "coupled" to another element, it may be directly connected or coupled to the other element, or there may be intervening elements. Conversely, when an element is referred to as being "directly connected" or "directly coupled" to another element, there are no intervening elements. Other words used to describe relationships between elements should be interpreted in a similar manner (i.e., "between" versus "directly between," "adjacent" versus "directly adjacent," etc.).

[0050] The terms used in this article are only for the purpose of describing specific exemplary embodiments and are not intended to limit the present invention. As used in this article, the singular forms "one", "an" and "said" are intended to also include plural forms, unless the context clearly indicates otherwise. It will be further understood that when the terms "include", "comprise", "contain" and / or "have" are used in this article, it is indicated that there are described features, values, steps, operations, elements and / or components, but it is not excluded that there are or add one or more other features, values, steps, operations, elements, components and / or groups thereof.

[0051] Unless otherwise defined, all terms (including technical and scientific terms) used in this article have the same meaning as those commonly understood by ordinary technicians in the field to which the present invention belongs. It will be further understood that terms (e.g., terms defined in commonly used dictionaries) should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and will not be interpreted as an idealized or overly formal meaning unless explicitly defined as such in this article.

[0052] The communication system according to the exemplary embodiment of the present invention will be described. The communication system according to the exemplary embodiment of the present invention is not limited to the content described below, and can be applied to various communication systems according to the exemplary embodiment of the present invention. Here, the communication system can have the same meaning as the communication network.

[0053] Throughout the present invention, the network may, for example, include wireless Internet such as wireless fidelity (WiFi), mobile Internet such as wireless broadband Internet (WiBro) or world interoperability for microwave access (WiMax), 2G mobile communication networks such as global system for mobile communications (GSM) or code division multiple access (CDMA), 3G mobile communication networks such as wideband code division multiple access (WCDMA) or CDMA2000, 3.5G mobile communication networks such as high speed downlink packet access (HSDPA) or high speed uplink packet access (HSUPA), 4G mobile communication networks such as long term evolution (LTE) networks or advanced LTE (LTE-Advanced) networks, 5G mobile communication networks, B5G mobile communication networks (6G communication networks, etc.), etc.

[0054] Throughout the present invention, a terminal may refer to a mobile station, a mobile terminal, a subscriber station, a portable subscriber station, a user equipment, an access terminal, etc., and may include all or part of the functions of a terminal, a mobile station, a mobile terminal, a subscriber station, a mobile subscriber station, a user equipment, an access terminal, etc.

[0055] Here, the following devices with communication capabilities can be used as terminals: desktop computers, laptop computers, tablet computers, wireless phones, mobile phones, smart phones, smart watches, smart glasses, e-book readers, portable multimedia players (PMP), portable game consoles, navigation devices, digital cameras, digital multimedia broadcasting (DMB) players, digital audio recorders, digital audio players, digital photo recorders, digital photo players, digital video recorders, digital video players, etc.

[0056] Throughout the present invention, a base station may refer to an access point, a radio access station, a NodeB (NB), an evolved NodeB (eNB), a base transceiver station, a mobile multi-hop relay (MMR)-BS, etc., and may include all or part of the functions of a base station, an access point, a radio access station, a NB, an eNB, a base transceiver station, an MMR-BS, etc.

[0057] Hereinafter, preferred exemplary embodiments of the present invention will be described in more detail with reference to the accompanying drawings. In describing the present invention, in order to facilitate overall understanding, the same elements in the drawings use the same reference numerals, and repeated description of the same elements is omitted.

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

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

[0060] The plurality of communication nodes 110 to 130 may support communication protocols defined in the 3rd Generation Partnership Project (3GPP) technical specifications (eg, LTE communication protocol, LTE-A communication protocol, NR communication protocol, etc.). The plurality of communication nodes 110 to 130 may support a communication protocol based on code division multiple access (CDMA), a communication protocol based on wideband CDMA (WCDMA), a communication protocol based on time division multiple access (TDMA), a communication protocol based on frequency division multiple access (FDMA), a communication protocol based on orthogonal frequency division multiplexing (OFDM), a communication protocol based on filtered OFDM, a communication protocol based on cyclic prefix OFDM (CP-OFDM), a communication protocol based on discrete Fourier transform-spread-OFDM (DFT-s-OFDM), a communication protocol based on orthogonal frequency division multiple access (OFDMA), a communication protocol based on single carrier FDMA (SC-FDMA), a communication protocol based on non-orthogonal multiple access (OFDM), ... The communication protocols include communication protocols based on generalized frequency division multiplexing (GFDM), communication protocols based on filter bank multi-carrier (FBMC), communication protocols based on universal filtered multi-carrier (UFMC), communication protocols based on space division multiple access (SDMA), etc. Each of the multiple communication nodes may have the following structure.

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

[0062] like Figure 2As shown, the device 200 may include at least one processor 210, a memory 220, and a transceiver 230 connected to a network for performing communication. In addition, the device 200 may further include an input interface device 240, an output interface device 250, a storage device 260, etc. The various components included in the device 200 can communicate with each other when connected through a bus 270.

[0063] The processor 210 may execute a program stored in at least one of the memory 220 and the storage device 260. The processor 210 may refer to a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which a method according to an embodiment of the present invention is executed. Each of the memory 220 and the storage device 260 may be composed of at least one of a volatile storage medium and a non-volatile storage medium. For example, the memory 220 may include at least one of a read-only memory (ROM) and a random access memory (RAM).

[0064] Reference again Figure 1 , the communication system 100 may include a plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2 and a plurality of 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 belong to the cell coverage of the first base station 110-1. In addition, the second terminal 130-2, the fourth terminal 130-4, and the fifth terminal 130-5 may belong to the cell coverage of the second base station 110-2. In addition, the fifth base station 120-2, the fourth terminal 130-4, the fifth terminal 130-5 and the sixth terminal 130-6 may belong to the cell coverage of the third base station 110-3. In addition, the first terminal 130-1 may belong to the cell coverage of the fourth base station 120-1, and the sixth terminal 130-6 may belong to the cell coverage of the fifth base station 120-2.

[0065] Here, each of the multiple base stations 110-1, 110-2, 110-3, 120-1 and 120-2 may be referred to as a NodeB (NB), an evolved NodeB (eNB), a gNB, an advanced base station (ABS), a high reliability base station (HR-BS), a base transceiver station (BTS), a radio base station, a radio transceiver, an access point (access point), an access node, a radio access station (RAS), a mobile multihop relay-base station (MMR-BS), a relay station (RS), an advanced relay station (ARS), a high reliability relay station (HR-RS), a home NodeB (HNB), a home eNodeB (HeNB), a road side unit (RSU), a radio remote head (RRH), a transmission point (transmission point), a base station (BTS), a radio transmitter ... point (TP), transmission and reception point (TRP), etc.

[0066] Each of the multiple terminals 130-1, 130-2, 130-3, 130-4, 130-5 and 130-6 can be called user equipment (UE), terminal equipment (TE), advanced mobile station (AMS), high reliability-mobile station (HR-MS), terminal, access terminal, mobile terminal, station, subscriber station, mobile station, portable subscriber station, node, device, on-board unit (OBU), etc.

[0067] On the other hand, each of the multiple base stations 110-1, 110-2, 110-3, 120-1 and 120-2 can operate in the same frequency band or different frequency bands. Multiple base stations 110-1, 110-2, 110-3, 120-1 and 120-2 can be connected to each other via an ideal backhaul link or a non-ideal backhaul link, and exchange information with each other via an 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 an ideal backhaul link or a non-ideal backhaul link. Each of the plurality of base stations 110-1, 110-2, 110-3, 120-1 and 120-2 may transmit a signal received from the core network to the corresponding terminal 130-1, 130-2, 130-3, 130-4, 130-5 or 130-6, and transmit a signal received from the corresponding terminal 130-1, 130-2, 130-3, 130-4, 130-5 or 130-6 to the core network.

[0068] In addition, each of the multiple base stations 110-1, 110-2, 110-3, 120-1 and 120-2 can support multiple-input multiple-output (MIMO) transmission (for example, single-user MIMO (SU-MIMO), multi-user MIMO (MU-MIMO), massive MIMO, etc.), coordinated multipoint (CoMP) transmission, carrier aggregation (CA) transmission, transmission in unlicensed frequency bands, device-to-device (D2D) communication (or, proximity service (ProSe)), Internet of Things (IoT) communication, dual connectivity (DC), etc. Here, each of the plurality of terminals 130-1, 130-2, 130-3, 130-4, 130-5, and 130-6 may perform operations corresponding to operations of the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2, operations supported by the plurality of base stations 110-1, 110-2, 110-3, 120-1, and 120-2, etc. For example, the second base station 110-2 may transmit a signal to the fourth terminal 130-4 in a SU-MIMO manner, and the fourth terminal 130-4 may receive a signal from the second base station 110-2 in a SU-MIMO manner. Alternatively, the second base station 110-2 may transmit a signal to the fourth terminal 130-4 and the fifth terminal 130-5 in a MU-MIMO manner, and the fourth terminal 130-4 and the fifth terminal 130-5 may receive a signal from the second base station 110-2 in a MU-MIMO manner.

[0069] Each of the first base station 110-1, the second base station 110-2, and the third base station 110-3 can send a signal to the fourth terminal 130-4 in a CoMP transmission manner, and the fourth terminal 130-4 can receive a signal from the first base station 110-1, the second base station 110-2, and the third base station 110-3 in a CoMP manner. In addition, each of the multiple base stations 110-1, 110-2, 110-3, 120-1, and 120-2 can exchange signals with the corresponding terminal 130-1, 130-2, 130-3, 130-4, 130-5, or 130-6 belonging to its cell coverage in a CA manner. Each of base stations 110-1, 110-2, and 110-3 may control D2D communication between the fourth terminal 130-4 and the fifth terminal 130-5, and thus the fourth terminal 130-4 and the fifth terminal 130-5 may perform D2D communication under the control of the second base station 110-2 and the third base station 110-3.

[0070] Hereinafter, a beam management method in a communication system will be described. Even when describing a method performed at a first communication node among communication nodes (e.g., transmission or reception of a data packet), the corresponding second communication node may also perform a method corresponding to the method performed at the first communication node (e.g., reception or transmission of a data packet). That is, when describing the operation of a terminal, the corresponding base station may perform an operation corresponding to the operation of the terminal. Conversely, when describing the operation of a base station, the corresponding terminal may perform an operation corresponding to the operation of the base station.

[0071] In an exemplary embodiment of the communication system, the network may include one or more base stations or one or more transmission and reception points (TRP). In particular, a communication environment in which multiple TRPs exist may be referred to as "multi-TRP (MTRP)". MTRP technology may refer to a technology in which a base station performs communication with a terminal by utilizing multiple physically separated TRPs. Based on MTRP technology, the problem of reduced quality of service (QoS) due to the distance of the cell edge terminal from the base station and the problem of inter-cell interference from base stations located in different cells can be solved. Based on MTRP technology, additional communication paths can be ensured in an environment (e.g., millimeter wave band) with limited non-line-of-sight (NLOS) paths.

[0072] MTRP technology can be divided into a coherent joint transmission (CJT) scheme and a non-coherent joint transmission (NCJT) scheme. In the CJT scheme, TRPs can cooperate with each other to support a single terminal in a synchronized manner. In the NCJT scheme, multiple TRPs can perform scheduling, precoding matrix selection, modulation coding scheme (MCS) determination, etc. non-cooperatively between them when they support a single terminal. In order to support MTRP technology, it may be necessary to enhance PDCCH, PUCCH, PUSCH, inter-cell operation, beam management, etc.

[0073] In the MTRP environment, beam indication for multiple beams can be performed for the terminal. In addition, in the MTRP environment, the terminal can receive multiple beams and report their performance. Here, in order to select the best beam (or beam combination) by taking into account the interaction between the beams formed by multiple TRPs in the beam management process, the transmission time or transmission mode of the reference signal sent by each TRP may need to be matched. In addition, in order to measure the performance of each beam combination, the beam switching period of each TRP may need to be determined by considering the number of candidate beams of other TRPs. In order to perform a joint beam management process in the MTRP environment, a technology may be required to match the CSI-RS transmission time and transmission mode between TRPs and enable each TRP to effectively switch beams.

[0074] In an exemplary embodiment of a communication system, an extension of a unified transmission configuration indication (TCI) framework may be considered. In the extension of the unified TCI framework, MTRP environments such as intra-cell MTRP and inter-cell MTRP may be considered. In the MTRP environment, a simultaneous transmission across multi-panel (STxMP) scheme may be applied.

[0075] At least in a unified TCI framework for MTRP based on single downlink control information (S-DCI), the TCI field within DCI format 1_1 / 1_2 can indicate multiple (joint, DL, UL, etc.) TCI states in one CC / BWP. Here, DCI format 1_1 / 1_2 can be a DCI format with or without DL allocation. At least in a unified TCI framework for MTRP based on single DCI, the TCI field within DCI format 1_1 / 1_2 can indicate a group of CC / BWPs in a CC list. Here, the mapping of TCI state IDs to TCI code points can be performed in various ways. For example, possible combinations of IDs of TCI states (e.g., joint, DL and / or UL) can be mapped to TCI code points.

[0076] The maximum number of TCI code points activated by the Medium Access Control (MAC) Control Element (CE) (e.g., 8 code points) can be increased, decreased, or maintained. The maximum number of bits in the TCI field (e.g., 3 or more bits) can be increased, decreased, or maintained.

[0077] In a unified TCI framework for MTRP based on multi-DCI (multi-DCI, M-DCI), the following may be considered for TCI status update.

[0078] - The TCI status update scheme for S-DCI based MTRP can be identically utilized.

[0079] - A TCI field within a DCI format 1_1 / 1_2 associated with one of the CORESETPoolIndex values ​​may be used to indicate all (joint, DL, UL, etc.) TCI states corresponding to the same CORESETPoolIndex value. Alternatively, a TCI field within a DCI format 1_1 / 1_2 may be used to indicate all (joint, DL, UL, etc.) TCI states corresponding to multiple CORESETPoolIndex values. Alternatively, a TCI field within a DCI format 1_1 / 1_2 associated with one of the CORESETPoolIndex values ​​may be used to indicate all (joint, DL, UL, etc.) TCI states corresponding to different CORESETPoolIndex values. Each CORESETPoolIndex value and its TCI state may be associated with each other in various ways.

[0080] In a unified TCI framework for S-DCI based MTRP, the following may be considered to map or associate TCI status (eg, joint / DL) to PDCCH reception.

[0081] -RRC configuration may be used to indicate the mapping / association between the configured or indicated (joint / DL) TCI states and a CORESET or CORESET group.

[0082] -RRC configuration may be used to indicate the mapping / association between the configured or indicated (joint / DL) TCI states and a search space set.

[0083] - MAC-CE may be used to indicate the mapping / association between an activated or indicated (joint / DL) TCI state and a CORESET or CORESET group.

[0084] - DCI may be used to indicate the mapping / association between the indicated (joint / DL) TCI state and a CORESET or CORESET group.

[0085] - Fixed mapping / association rules can be utilized.

[0086] If groupBasedBeamReporting-r17 in the higher layer parameter CSI-ReportConfig is configured and repetition of the corresponding resource set is set to "on", the CSI-RS Resource Indicator (CRI) may not be reported.

[0087] In the M-DCI-based inter-cell MTRP environment, the SSB associated with the additional PCI can be configured as an NBI-RS in the NBI-RS set. The NBI-RS set can be associated with the BFD-RS set associated with the additional PCI.

[0088] If groupBasedBeamReporting-r17 in the higher layer parameter CSI-ReportConfig is configured, it can support configuring the same or different CSI-RS triggering offset values ​​for two different CSI resource sets.

[0089] If groupBasedBeamReporting-r17 in the higher layer parameter CSI-ReportConfig is configured, the same or different repetition values ​​for different CSI resource sets can be set for the terminal. The terminal can report CRI regardless of whether the repetition value is set to "on".

[0090] In the MTRP environment according to an exemplary embodiment of the communication system, the CJT scheme and the NCJT scheme can be determined according to the cell environment in which the TRP currently exists, the backhaul link connectivity, etc. In the MTRP environment, a group-based beam reporting scheme can be utilized, in which beams formed by multiple TRPs are grouped into one group, and the terminal reports the performance of each group to the TRP.

[0091] In the MTRP environment according to the exemplary embodiment of the communication system, a simultaneous transmission across multiple panels (STxMP) scheme may be applied.

[0092] In the MTRP environment according to the exemplary embodiment of the communication system, a beam management process between a terminal having one panel or more panels and multiple TRPs can be performed. The terminal can assign one or more TRPs to one of its panels (e.g., TRP A-UE panel A, TRP B-UE panel B, etc.). The terminal can report the performance of each beam group to the TRP according to a group-based beam reporting scheme. Here, multiple TRPs can be assigned to one panel of the terminal, or multiple panels of the terminal can be assigned to one TRP.

[0093] When TRP A and TRP B independently perform beam management processes through UE Panel A and UE Panel B, it may not be possible to ensure that the beam selected from each TRP is the optimal beam from the perspective of the terminal. In addition, the beam of one TRP may cause high interference to the beam of another TRP, resulting in failure of the beam in one or more TRPs. In an MTRP environment, when the terminal performs beam management processes with multiple TRPs, a joint beam management process may be required that takes into account the impact of the beam formed by one TRP on the beam formed by another TRP. Specifically, to support this, the TRP can send and receive information about TRP ID, the number of candidate beams, CSI-RS transmission time and transmission mode, etc. This information transmission and reception can be performed via a backhaul between TRPs or between base stations connected to the TRPs (see Figure 4 and Figure 5 ). Alternatively, such information transmission and reception may be performed via a terminal (see Figures 6a to 7b ). In addition, based on this information sending and receiving, the beam switching period can be determined, the performance of each beam combination can be measured, and the best beam combination can be selected.

[0094] In an exemplary embodiment of a communication system, a beam management process may be performed based on steps such as an initial setup, beam adjustment, and beam recovery process. The beam management process may be performed by measuring the performance of each beam while switching beams based on beam scanning and selecting the beam with the best performance. During the initial setup process, a wide beam may be primarily used to determine the beam direction. During the beam adjustment process, more detailed beamforming may be used to determine the best beam. During the beam recovery process, if a certain level of performance is not met when communicating using a predetermined beam, a new beam may be selected when the terminal sends a beam failure detection (BFD) to the TRP.

[0095] Reference Figures 3 to 14 At least some of the exemplary embodiments described may be described based on the following situation: two TRPs (hereinafter, TRP A and TRP B) support a single terminal in an MTRP environment, and approximate beam directions are determined for the two TRPs through an initial setup process. After the initial setup process, a joint beam adjustment process may be performed to select the best beams for the two TRPs, taking into account the impact of the beams formed by each of TRP A and TRP B on the beam of the other TRP when communicating with the terminal.

[0096] Figure 3 is a sequence diagram describing a first exemplary embodiment of a beam management method in a communication system.

[0097] like Figure 3 As shown, the communication system 300 may include one or more TRPs and one or more terminals. For example, the communication system 300 may include TRP A 301, TRP B 302, and terminal 303. In the communication system 300, TRP A 301 and TRP B 302 may be connected to the same base station. Alternatively, in the communication system 300, TRP A 301 and TRP B 302 may be connected to different base stations. TRP A 301 and TRP B 302 may support the same terminal 303. In the following, in reference to Figure 3 In the first exemplary embodiment of the beam management method in the communication system, the reference Figure 1 and Figure 2 Description of duplicate description.

[0098] In the first exemplary embodiment of the beam management method, a rough or approximate beam direction may be determined through an initial establishment process between TRP 301 and TRP 302 and terminal 303. Based on the beam direction determination result, a beamforming direction may be configured through a fine beam direction configuration process or a beam adjustment process. Therefore, an optimal beam (or beam combination) for communication between TRP 301 and TRP 302 and terminal 303 may be selected.

[0099] TRP 301 and TRP 302 may configure a beam candidate group to be utilized in a beam adjustment process for communicating with terminal 303. For example, the beam candidate group of each of TRP 301 and TRP 302 may be configured as shown in Table 1.

[0100] [Table 1]

[0101]

[0102] Specifically, TRP A 301 may perform a beam candidate group configuration operation (S311). The beam candidate group of TRP A 301 configured in step S311 may include three candidate beams. Each of the three candidate beams included in the beam candidate group of TRP A 301 may be referred to as beam #A-1, beam #A-2, and beam #A-3. TRP B 302 may perform a beam candidate group configuration operation (S312). The beam candidate group of TRP B 302 configured in step S312 may include five candidate beams. The five candidate beams included in the beam candidate group of TRP B 302 may be referred to as beam #B-1, beam #B-2, beam #B-3, beam #B-4, and beam #B-5. This is merely an example for ease of description, and the first exemplary embodiment of the beam management method in a communication system is not limited thereto. For example, the beam candidate group configuration results shown in Table 1 can be extended to an exemplary embodiment in which TRP A 301 configures N_A candidate beams and TRP B 302 configures N_B candidate beams. Here, N_A and N_B may be natural numbers.

[0103] Based on the number of candidate beams configured in each of TRP 301 and TRP 302, the number of combinations of beams (or "beam combinations") formed by TRP 301 and TRP 302 may be determined. For example, if TRP A 301 configures three candidate beams and TRP B 302 configures five candidate beams, the number of beam combinations formed by TRP 301 and TRP 302 may be 15. If TRP A 301 configures N_A candidate beams and TRP B 302 configures N_B candidate beams, the number of beam combinations formed by TRP 301 and TRP 302 may be (N_A*N_B).

[0104] Based on the first exemplary embodiment of the beam management method in the communication system, one or more beam combinations can be configured. A process for selecting an optimal beam combination with the best performance in the configured beam combinations can be performed. For example, at least some of the communication nodes 301, 302, and 303 included in the communication system 300 can perform operations according to at least some of the second to twelfth exemplary embodiments of the beam management method in the communication system described later. Therefore, the optimal beam combination for beam-based communication between TRP 301 and TRP 302 and terminal 303 can be selected.

[0105] In the following, reference Figure 4 and Figure 5, an exemplary embodiment will be described based on a situation in which a backhaul is formed between TRPs or between base stations connected to TRPs in an MTRP environment and information is sent and received between TRPs via the backhaul.

[0106] Figure 4 is a sequence diagram describing a second exemplary embodiment of a beam management method in a communication system.

[0107] like Figure 4 As shown, the communication system 400 may include one or more TRPs and one or more terminals. For example, the communication system 400 may include TRP A 401, TRP B 402, and terminal 403. In the communication system 400, TRP A 401 and TRP B 402 may be connected to the same base station. TRP A 401 and TRP B 402 may perform information transmission and reception between each other via a backhaul, etc. TRP A 401 and TRP B 402 may support the same terminal 403. In the following, in reference to Figure 4 In the second exemplary embodiment of the beam management method in the communication system, the reference Figures 1 to 3 Description of duplicate description.

[0108] In a multi-TRP (i.e., MTRP) environment, multiple TRPs can simultaneously send channel state information (CSI)-reference signal (RS) at a specific time. In this case, the terminal can receive the CSI-RS sent from the TRP and perform performance verification measurements for all possible beam combinations. For this purpose, a process for TRP confirmation or matching of CSI-RS transmission patterns between TRPs and / or a process for each appropriately configured beam switching period for the TRP may be required.

[0109] In a second exemplary embodiment of the beam management method in a communication system, if it is determined that the initial establishment process is completed and the joint beam adjustment process starts, an operation can be performed in which TRP A, which acts as a reference TRP, sends information about its CSI-RS transmission time and transmission mode to TRP B via a backhaul. Figure 4 The process shown can be performed in such a way that another TRP matches its CSI-RS transmission time and transmission mode with the CSI-RS transmission time and transmission mode of TRP A, which serves as a reference TRP. Alternatively, all TRPs can select new CSI-RS transmission time and transmission mode based on another TRP or through collaboration between TRPs. For this purpose, a process in which all TRPs exchange their CSI-RS transmission time and transmission mode with other TRPs can be additionally considered.

[0110] In a second exemplary embodiment of a beam management method in a communication system, a reference TRP may be determined in TRP 401 and TRP 402 connected to the same base station (not shown). For example, TRP A 401 may be determined as a reference TRP. TRP A 401 as a reference TRP may send information to TRP B 402 via a link between TRP 401 and TRP 402 or in a backhaul between base stations connected to TRP 401 and TRP 402. For example, TRP A 401 may send information about a transmission time, a transmission mode, etc. of a first reference signal to TRP B 402 (S421). TRP B 402 may receive information about a transmission time, a transmission mode, etc. of a first reference signal sent from TRP A 401 (S421). Here, the first reference signal may be a CSI-RS. The information transmission operation according to step S421 may be represented, for example, as shown in Table 2.

[0111] [Table 2]

[0112] path Information sent TRP A → TRP B CSI-RS transmission time and mode of TRP A

[0113] Although Figure 4 An exemplary embodiment in which TRP A 401 is determined as a reference TRP is shown, but this is merely an example for ease of description, and the second exemplary embodiment of the beam management method in a communication system is not limited thereto. For example, a base station (or a network, etc.) may determine a reference TRP based on the order of TRP IDs. On the other hand, the base station may determine a TRP with higher (or lower) resource utilization as a reference TRP, so that a TRP with more available resources may be consistent with the reference TRP in terms of resource utilization. Alternatively, the base station may utilize a method in which a reference TRP is selected based on other circumstances or criteria and other TRPs are allowed to match the CSI-RS transmission time and transmission mode with the CSI-RS transmission time and transmission mode of the reference TRP.

[0114] TRP B 402, which receives information about the CSI-RS transmission time and transmission mode of TRP A 401, can transmit CSI-RS simultaneously with TRP A 401 by utilizing the received information. In addition, a joint beam adjustment process can be subsequently performed, which selects the best beam combination by considering the influence of the beam formed by each TRP on other TRPs and based on this. In the present invention, it is assumed that Figure 4In the case where there are two TRPs communicating with the terminal 403, TRP A 401 sends information about its CSI-RS transmission time and transmission mode to only one TRP, but when there are three or more TRPs communicating with the terminal 403, the reference TRP can send information about its CSI-RS transmission time and transmission mode to all other TRPs communicating with the terminal 403. Therefore, Figure 4 The following process is shown: the reference TRP sends information about its CSI-RS transmission time and transmission mode to other TRPs, and other TRPs match their CSI-RS transmission time and transmission mode with the reference TRP based on the information received from the reference TRP. In addition, considering the situation that it is difficult for other TRPs to transmit CSI-RS using the same transmission time and transmission mode as the reference TRP, Figure 4 During the process, TRP B 402 may also send information about its CSI-RS to TRP A 401, and may select a new CSI-RS transmission time and transmission mode based on an agreement between TRP A 401 and TRP B 402 on the CSI-RS transmission time and transmission mode.

[0115] Figure 5 is a sequence diagram for describing a third exemplary embodiment of a beam management method in a communication system.

[0116] like Figure 5 As shown, the communication system 500 may include one or more TRPs and one or more terminals. For example, the communication system 500 may include TRP A 501, TRP B 502, and terminal 503. In the communication system 500, TRP A 501 and TRP B 502 may be connected to the same base station. TRP A 501 and TRP B 502 may perform information transmission and reception between each other via a backhaul, etc. TRP A 501 and TRP B 502 may support the same terminal 503. In the following, in reference to Figure 5 In the third exemplary embodiment of the beam management method in the communication system, the reference Figures 1 to 4 Description of duplicate description.

[0117] In a third exemplary embodiment of the beam management method in a communication system, TRP A and TRP B may send information about their TRP IDs and information about candidate beams (e.g., the number of candidate beams) to each other. Then, the following process may be performed: the terminal sends information about the number of its candidate beams to all TRPs, and then each TRP determines all beam combinations based on the number of candidate beams of other TRPs received by each TRP and the number of candidate beams of the terminal, and configures its beam switching period.

[0118] In the third exemplary embodiment of the beam management method in the communication system, TRP A 501 and TRP B 502 can send and receive information about TRP ID and information about candidate beams (e.g., the number of candidate beams) to each other (S524). Terminal 503 can send information about its candidate beams (e.g., the number of candidate beams) to TRP A 501 and TRP B 502 (S526, S527). TRP A 501 and TRP B 502 can each configure their own beam switching period (S528, S529).

[0119] Specifically, TRP A 501 and TRP B 502 may transmit information about their own TRP IDs and information about the number of candidate beams to other TRPs via a backhaul between TRPs or between base stations (not shown) connected to the TRPs, and the terminal 503 may transmit information about the number of its own candidate beams to all TRPs 501 and TRP 502. This process may be performed the same as or similar to the following Table 3.

[0120] [Table 3]

[0121]

[0122] In addition, each of TRP 501 and TRP 502 can identify all beam combinations based on the number of candidate beams received from other TRPs and terminals, and then configure its own beam switching period. The process can be performed the same as or similar to the following Table 4.

[0123] [Table 4]

[0124] TRP Beam switching period TRPA 5 TRP B 1

[0125] because Figure 5Assume that there are two TRPs communicating with the terminal, so it shows the case where each TRP sends information about its TRP ID and information about the number of its candidate beams to only one other TRP. However, when there are three or more TRPs communicating with the terminal, each TRP can send information about its TRP ID and information about the number of its candidate beams to all other TRPs communicating with the terminal. The process of each TRP sending information about its TRP ID and information about the number of its candidate beams to other TRPs can be performed via a backhaul between TRPs or between base stations connected to the TRPs, such as Figure 4 After that, each TRP can determine the total beam combination based on the number of candidate beams received from other TRPs and terminals. Figure 5 Assuming that the terminal has one candidate beam, TRP A can know that the total number of beam combinations is 15 based on its own candidate beam number 3 and the candidate beam number 5 of TRP B received from TRP B. In addition, TRP A can know that the number of different beam combinations that one of its candidate beams can form with the beam of another TRP is 5. In order to measure the performance of all beam combinations that can be formed during the joint beam adjustment process, it is necessary to configure an appropriate beam switching period at each TRP. In the present invention, two methods for configuring the beam switching period can be considered: 1) method: all TRPs exchange information about the number of their respective candidate beams, and then configure the beam switching period according to a predetermined sequence announced by the reference TRP; and 2) method: all TRPs except the reference TRP send information about the number of their respective candidate beams to the reference TRP, and the reference TRP calculates an appropriate beam switching period for each TRP based on the number of candidate beams of all TRPs and sends the calculated beam switching period to all other TRPs.

[0126] For example, in the case where three TRPs, namely TRP A, TRP B, and TRP C, communicate with the terminal, it can be assumed that the numbers of candidate beams of the TRPs are 3, 4, and 5, respectively. In the case where there are three or more TRPs, for example, if the order of the TRPs is TRP A, TRP B, and TRP C, TRP C can configure its beam switching period to 1, TRP B can configure its beam switching period to correspond to the number of beams of TRP C, and TRP A can configure its beam switching period to correspond to the number of beam combinations of TRP B and TRP C.

[0127] In the case of method 1), TRP A acting as a reference TRP can determine the order of the TRPs and send information about the beam switching priority of the TRPs to all TRPs via the backhaul between the TRPs or between the base stations connected to the TRPs. Then, after the three TRPs exchange information about the number of their candidate beams via the backhaul between the TRPs or between the base stations connected to the TRPs, each TRP can determine its own beam switching period based on the number of beams of all TRPs and the beam switching priority of the TRP. In other words, TRP A can configure its beam switching period to 20, TRP B can configure its beam switching period to 5, and TRP C can configure its beam switching period to 1.

[0128] In the case of method 2), all TRPs except the reference TRP (i.e., TRP B and TRP C) may send information about the number of their candidate beams to the reference TRP (i.e., TRP A) via the TRP or the backhaul between base stations connected to the TRP. TRP A may configure beam switching periods for all TRPs based on the number of its own beams and the number of beams of other TRPs it receives, and send information about the beam switching period to other TRPs via the backhaul between TRP or the base stations connected to the TRP. Since TRP A knows the number of beams of all TRPs, for example, TRP A may configure the beam switching period of TRP C to 1, the beam switching period of TRP B to 5, and the beam switching period of TRP A to 20, and then send information about the configured beam switching period to all TRPs via the backhaul between TRP or the base stations connected to the TRP.

[0129] After all TRPs have configured their beam switching periods, if a process is needed in which all TRPs determine whether their beam switching periods are properly configured, all TRPs may send information about their configured beam switching periods to a reference TRP via a backhaul between TRPs or between base stations connected to the TRPs, and the reference TRP may determine whether all TRPs have properly configured their beam switching periods based on the beam switching periods received from other TRPs and the beam switching priorities of the TRPs.

[0130] In an example of the present invention, when each TRP configures its beam switching period, after determining the number of candidate beams of other TRPs, TRP B can configure its beam switching period to 1, and TRP A can configure its beam switching period to 5 (which is the number of candidate beams of TRP B). Assuming that the terminal has multiple beams instead of just one beam, in the same manner as an environment with three TRPs, for example, if the beam switching priority is set in the order of TRP A, TRP B, and the terminal, the terminal can configure its beam switching period to 1, TRP B can configure its beam switching period to correspond to the number of beams of the terminal, and TRP A can configure its beam switching period to correspond to the number of beam combinations of TRP B and the terminal. Figure 5 In the joint beam adjustment process, TRP A can repeat a beam identically 5 times and then change to another beam, while TRP B can change to a different beam each time it sends a beam. In addition, since TRPA and TRP B can determine the number of all beam combinations based on the number of candidate beams of other TRPs received in advance, TRP A can determine that the reference signal transmission for all beam combinations is completed after performing two beam switches, and TRP B can determine that the reference signal transmission for all beam combinations is completed after performing 14 beam switches. In the case where the configured beam switching period needs to be sent to the terminal, the information of the configured beam switching period can be sent to the terminal by using the information of "ENUMERATED{on,off}" in the parameter repetition in the NZP-CSI-ResourceSet IE through RRC reconfiguration defined in the existing standard, or the information of the configured beam switching period can be sent to the terminal by newly defining the parameter nrofRepetition, which is information about how many times a beam is repeated in the NZP-CSI-RS-ResourceSet IE. Alternatively, it can be sent to the terminal through DCI or other new RRC signaling.

[0131] according to Figure 4 and Figure 5According to the operation disclosed in the embodiment, the TRP corresponding to the reference TRP can send information about its own CSI-RS transmission time (i.e., transmission time and transmission mode) to other TRPs via the backhaul between TRPs or between base stations connected to the TRPs, so that the CSI-RS transmission time and transmission mode of all TRPs communicating with the terminal can match its own CSI transmission time and mode. In addition, after all TRPs communicating with the terminal receive information about the number of candidate beams of all other TRPs and terminals, each TRP can configure its own beam switching period so that all TRPs and terminals can sequentially measure the performance of each beam combination.

[0132] In the following, reference Figures 6a to 7b , an exemplary embodiment will be described based on the following case: there is no backhaul between TRPs or between base stations connected to TRPs in an MTRP environment, or even if there is a backhaul, it is not easy to transmit information via the backhaul due to various reasons. Figure 4 and Figure 5 The information described in the exemplary embodiment shown as being sent and received between TRPs via the backhaul can be sent and received by the terminal. Figures 6a to 7b The figure shows a preliminary process for exchanging necessary information between TRPs when each TRP matches the CSI-RS transmission time and configures an appropriate beam switching period to perform joint beam adjustment in an MTRP environment. That is, when it is impossible to exchange information via a backhaul between TRPs or between base stations connected to the TRPs, Figures 6a to 7b The exemplary embodiment shown may be implemented according to Figure 3 The operations of the illustrated exemplary embodiment are performed thereafter.

[0133] Figure 6a and Figure 6b is a sequence diagram for describing a fourth exemplary embodiment and a fifth exemplary embodiment of a beam management method in a communication system.

[0134] like Figure 6a and Figure 6b As shown, the communication system 600 may include one or more TRPs and one or more terminals. For example, the communication system 600 may include TRP A 601, TRP B 602, and terminal 603. In the communication system 600, TRP A 601 and TRP B 602 may be connected to different base stations. TRP A 601 and TRP B 602 may support the same terminal 603. TRP A 601 and TRP B 602 may perform information transmission and reception between each other via terminal 603. Figure 6a and Figure 6bIn the fourth exemplary embodiment and the fifth exemplary embodiment describing the beam management method in the communication system, the reference numerals may be omitted. Figures 1 to 5 Description of duplicate description.

[0135] Figure 6a FIG. 6 shows a process in which TRP A 601 transmits information about its CSI-RS transmission time and transmission mode to the terminal 603 and the terminal 603 receives the information through the UE panel A. Figure 6a , TRP A 601 may transmit information about its TRP ID (eg, TRP ID_A) and information about a transmission time and a transmission mode of a first reference signal to the terminal 603 (S621).

[0136] Figure 6b It shows that the terminal 603 will be Figure 6a The process of forwarding the information about the CSI-RS transmission time and transmission mode of TRP A 601 received during the process to TRP B 602. Figure 6b , the terminal 603 may send the information received in step S621, ie, information about the TRP ID of the TRP A 601 and the transmission time and transmission mode of the first reference signal, to the TRPB 602 (S622).

[0137] Specifically, refer to Figure 6a In the fourth exemplary embodiment of the beam management method in the communication system, in the case where TRP A 601 and TRP B 602 communicate with UE panel A and UE panel B of terminal 603 respectively, TRP A 601 may perform a process for transmitting information about its own TRP ID and information about CSI-RS transmission time and transmission mode to terminal 603 through a communication link between TRP A 601 and UE panel A. The process may be performed the same as or similar to, for example, Table 5.

[0138] [Table 5]

[0139] path Information sent TRP A → UE Panel A TRP ID_A, CSI-RS transmission time and transmission mode of TRP A

[0140] exist Figure 6a and Figure 6b In the example, the signaling operations between TRPs can be as follows: Figure 4 In this case, unlike Figure 4 , since information cannot be sent via the backhaul between TRPs or between base stations connected to TRPs, Figure 6aIt may correspond to a process in which TRP A 601 first sends information about its CSI-RS transmission time and transmission mode to the terminal 603. The information about the CSI-RS transmission time and transmission mode of TRP A 601 may be sent to the terminal 603 by RRC reconfiguration using the parameter CSI-RS-ResourceMapping within the NZP-CSI-RS-Resource IE. In addition, in the information constituting the CSI-RS-ResourceMapping, the information about the CSI-RS transmission time may correspond to firstOFDMSymbolInTimeDomain, and the information about the transmission mode may correspond to cdm-Type or frequencyDomainAllocation. In addition, TRP A 601, which acts as a reference TRP, may send information about its CSI-RS transmission time and transmission mode to the terminal 603 through DCI or other new RRC signaling.

[0141] refer to Figure 6b In a fifth exemplary embodiment of a beam management method in a communication system, the terminal 603 may execute a method for Figure 6a The process of transmitting the ID of TRP A 601 received from TRP A 601 and the information about the CSI-RS transmission time and transmission mode of TRP A 601 to TRP B 602. The process may be performed the same as or similar to Table 6, for example.

[0142] [Table 6]

[0143] path Information sent UE Panel B → TRP B TRP ID_A, CSI-RS transmission time and transmission mode of TRP A

[0144] exist Figure 6b In the embodiment, the terminal 603 can send information about the CSI-RS transmission time and transmission mode of TRP A 601 to TRP B 602 by utilizing the communication link pre-established between TRP B 602 and UE panel B, and then TRP B 602 can match its CSI-RS transmission time and transmission mode with the CSI-RS transmission time and transmission mode of TRP A 601 based on the information received from the terminal 603. Figure 6bIn the present invention, since it is assumed that there is only one TRP other than the reference TRP communicating with the terminal 603, the terminal 603 sends information about the CSI-RS transmission time and transmission mode of TRP A 601 only to TRP B 602, but in the case where there are three or more TRPs, the same information can be sent to all other TRPs except TRP A 601 which is the reference TRP. If TRP B 602 is connected to the same base station as the base station to which TRP A 601 is connected, the terminal 603 may send the information about the CSI-RS transmission time and transmission mode of TRP A 601 received from TRP A 601 to TRP B 602 through UCI, UE auxiliary information or other new RRC signaling, and if TRP B 602 is connected to a base station different from the base station to which TRP A 601 is connected, the terminal 603 may send the information about the CSI-RS transmission time and transmission mode of TRP A 601 to TRP B 602 through Msg1 or MsgA, or may send the information through UE auxiliary information of SRB3 or other new SRB3 signaling.

[0145] Figure 7a and Figure 7b is a sequence diagram for describing the sixth exemplary embodiment and the seventh exemplary embodiment of the beam management method in the communication system.

[0146] like Figure 7a and Figure 7b As shown, the communication system 700 may include one or more TRPs and one or more terminals. For example, the communication system 700 may include TRP A 701, TRP B 702, and terminal 703. In the communication system 700, TRP A 701 and TRP B 702 may be connected to different base stations. TRP A 701 and TRP B 702 may support the same terminal 703. TRP A 701 and TRP B 702 may perform information transmission and reception between each other via terminal 703. In the following, in reference to Figure 7a and Figure 7b In the sixth exemplary embodiment and the seventh exemplary embodiment describing the beam management method in the communication system, the Figures 1 to 6b Description of duplicate description.

[0147] Figure 7a A process is shown in which TRP A 701 and TRP B 702 communicating with the terminal 703 transmit information about their own TRPIDs and the number of their candidate beams to the terminal 703. Figure 7b The terminal 703 is shown based on Figure 7aThe process of sending information about the number of its own candidate beams, the TRP ID of TRP B 702, and the number of candidate beams of TRP B 702 to TRP A 701 and sending information about the number of its own candidate beams, the TRP ID of TRP A 701, and the number of candidate beams of TRP A 701 to TRP B 702 based on the information received from the terminal 703. Then, based on the information received from the terminal 703, TRP A 701 and TRP B 702 can identify all beam combinations and configure their beam switching periods.

[0148] refer to Figure 7a In the sixth exemplary embodiment of the beam management method in the communication system, TRP A 701 may send information about its TRP ID and the number of its candidate beams to the terminal 703 (S724). Figure 7a , in the sixth exemplary embodiment of the beam management method in the communication system, TRP B 702 may send information about its TRP ID and the number of its candidate beams to the terminal 703 (S725).

[0149] The terminal 703 may send the information received in step S725, i.e., the TRP ID of TRP B 702 and the number of candidate beams to TRP A 701 (S726). The terminal 703 may send the information received in step S724, i.e., the TRP ID of TRP A 701 and the number of candidate beams to TRP B 702 (S727). TRP A 701 and TRP B 702 may each configure their own beam switching period (S728, S729). The operations according to steps S726 to S729 may be the same as those according to reference 1. Figure 7b The operations of steps S727 to S729 described are the same or similar.

[0150] refer to Figure 7a In the sixth exemplary embodiment of the beam management method in the communication system, in the case where TRP A 701 and TRP B 702 communicate with UE panel A and UE panel B of terminal 703, respectively, TRP A 701 and TRP B 702 may perform a process for sending information about their own TRP IDs and the number of their own candidate beams to terminal 703 through a communication link between TRP A 701 and UE panel A and a communication link between TRP B 702 and UE panel B, respectively. The above process may be performed the same as or similar to, for example, Table 7.

[0151] [Table 7]

[0152] path TRP ID Information sent TRP A → UE Panel A TRP ID_A The number of candidate beams for TRP A TRP B → UE Panel B TRP ID_B The number of candidate beams for TRP B

[0153] exist Figure 7a and Figure 7b In the , you can execute Figure 5 signaling operations for similar purposes. In this case, due to the difference between Figure 5 The information cannot be sent via the backhaul between TRPs or between base stations connected to TRPs, so Figure 7a Corresponding to a process in which TRP A 701 and TRP B 702 first send information about their TRP IDs and the number of their candidate beams to the terminal 703. When there are three or more TRPs communicating with the terminal 703, all TRPs communicating with the terminal 703 can send information about their TRP IDs and information about the number of their candidate beams to the terminal 703. TRP A 701, which is a reference TRP, can send information about its own TRP ID to the terminal 703 through SIB, DCI, RRC reconfiguration or other new RRC signaling, and can send information about the number of its own candidate beams by using the parameter NZP-CSI-RS-ResourceId in the NZP-CSI-RS-ResourceSet IE through RRC reconfiguration or through SIB, DCI or other new RRC signaling. If TRP B 702 is connected to the same base station as the base station to which TRP A 701 is connected, similar to TRP A 701, TRP B 702 can send information about its TRP ID to the terminal 703 through SIB, DCI, RRC reconfiguration or other new RRC signaling, and can send information about the number of its candidate beams by RRC reconfiguration using the parameter NZP-CSI-RS-ResourceId in the NZP-CSI-RS-ResourceSet IE or through SIB, DCI or other new RRC signaling. In addition, if TRP B 702 is connected to a base station different from the base station to which TRP A 701 is connected, TRP B 702 can send information about its own TRP ID and information about the number of its candidate beams through SIB, DCI, Msg2, MsgB or other new SRB3 signaling.

[0154] refer to Figure 7b In a seventh exemplary embodiment of a beam management method in a communication system, based on Figure 7aThe terminal 703 may perform the following process: sending information about the TRP ID and the number of candidate beams of TRP A 701 to TRP B 702, and conversely sending information about the TRP ID and the number of candidate beams of TRP B 702 to TRP A 701. In addition, the terminal 703 may perform a process of sending information about the number of its own candidate beam information to all TRPs. The above process may be performed the same as or similar to, for example, Table 8.

[0155] [Table 8]

[0156]

[0157] exist Figure 7b In the embodiment, the terminal 703 can send information about the TRP ID and the number of candidate beams of other TRPs and information about the number of candidate beams of its own to TRP A 701 and TRP B 702 respectively by utilizing the communication link between TRP A 701 and UE panel A and the communication link between TRP B 702 and UE panel B pre-established with TRP A 701 and TRP B 702. Then, TRP A 701 and TRP B 702 can set their own beam switching period based on the received information. The above operation can be performed the same as or similar to, for example, Table 9.

[0158] [Table 9]

[0159]

[0160]

[0161] Figure 7b An example is shown in which the terminal 703 transmits the TRPID of one TRP and the information of the number of candidate beams to each of TRP A 701 and TRP B 702. However, when there are three or more TRPs communicating with the terminal 703, the terminal 703 may transmit information about the TRP IDs and the number of candidate beams of all other TRPs communicating with itself except TRP A 701 to TRP A 701, and transmit such information to the remaining TRPs in the same manner. In addition, although the present invention considers the case where the terminal 703 has only one candidate beam, if it is assumed that the terminal 703 has a plurality of beams instead of only one beam, the same as described above may be utilized. Figure 5For example, if the beam switching priority is configured in the order of TRP A 701, TRP B 702, and terminal 703, terminal 703 can configure its beam switching period to 1, TRP B 702 can configure its beam switching period to correspond to the number of beams of terminal 703, and TRP A 701 can configure its beam switching period to the number of beam combinations of TRP B 702 and terminal 703. Therefore, each TRP can be configured to communicate with the terminal 703 based on the information received from the terminal 703. Figure 5 The beam switching period is configured in the same way and is similar to Figure 5 , Figure 7b An example is shown in which TRP A 701 configures its beam switching period to 5 and sets the beam switching period of TRP B to 1. The terminal 703 may transmit the information on the TRP ID and the number of candidate beams received from TRP B 702 and the information on the number of its own candidate beams to TRP A 701 through UCI, UE assistance information, or other new RRC signaling. If TRP B 702 is connected to the same base station as the base station to which TRP A 701 is connected, the terminal 703 may transmit the information on the TRP ID and the number of candidate beams received from TRP A 701 and the information on the number of its own candidate beams to TRP B 702 through UCI, UE assistance information, or other new RRC signaling in the same manner as in the case of TRP A 701. If TRP B 702 is connected to a base station different from the base station to which TRP A701 is connected, the terminal 703 can send the information about the TRP ID and the number of candidate beams received from TRP A701 and the information about the number of its own candidate beams to TRP B702 via Msg1 or MsgA or via UE auxiliary information of SRB3 or other new SRB3 signaling.

[0162] In addition, after all TRPs are configured with beam switching periods, if a process is necessary in which it is necessary to determine whether all TRPs are properly configured with beam switching periods, all TRPs may send information about their configured beam switching periods to a reference TRP via terminal 703, and the reference TRP may determine whether all TRPs are properly configured with beam switching periods based on the beam switching periods received from other TRPs and the beam switching priorities of the TRPs. When the beam switching period configured by TRPB 702 needs to be sent to the terminal 703, if TRP B 702 is connected to the same base station as the base station to which TRP A 701 is connected, TRP B 702 can send information about the number of repetitions of the configured beam by reconfiguring the existing RRC using the information "ENUMERATED{on,off}" of the parameter repetition in the NZP-CSI-ResourceSet IE, thereby sending the information about the configured beam switching period to the terminal 703, or can send the information about the configured beam switching period to the terminal 703 by newly defining a parameter nrofRepetition, which is information about how many times a beam is repeated in the NZP-CSI-RS-ResourceSet IE. Alternatively, TRP B can send the information to the terminal 703 through DCI or other new RRC signaling. When the configured beam switching period needs to be sent to the terminal 703, if TRP B 702 is connected to a base station different from the base station to which TRP A 701 is connected, information about the beam switching period can be sent through DCI, Msg2, MsgB or other new SRB3 signaling. When the terminal 703 sends the beam switching period of other TRPs to TRP A 701 as the reference TRP, the terminal 703 can send them through UCI or UE auxiliary information or other new RRC signaling as described above.

[0163] refer to Figures 6a to 7b The exemplary embodiment shown, Figure 6a and Figure 6b A process is shown in which TRP A, which acts as a reference TRP in the joint beam adjustment process of the MTRP environment, sends its CSI-RS transmission time and pattern information to other TRPs via the terminal to synchronize the CSI-RS transmission time of each TRP. Figure 7a and Figure 7bA process is shown in which all TRPs communicating with a terminal send their own TRP IDs and information about the number of candidate beams to all other TRPs via the terminal. After receiving information about the number of candidate beams of the terminal and the TRP IDs and the number of candidate beams of other TRPs, each TRP can identify all beam combinations based on this information and configure its beam switching period accordingly.

[0164] Figure 8 is a flow chart for describing an eighth implementation of a beam management method in a communication system.

[0165] like Figure 8 As shown, the communication system 800 may include one or more TRPs and one or more terminals. For example, the communication system 800 may include TRP A 801, TRP B 802, and terminal 803. In the communication system 800, TRP A 801 and TRP B 802 may be connected to the same base station. Alternatively, in the communication system 800, TRP A 801 and TRP B 802 may be connected to different base stations. TRP A 801 and TRP B 802 may support the same terminal 803. In the following, in reference to Figure 8 In the eighth exemplary embodiment of the beam management method in the communication system, the reference Figures 1 to 7b Description of duplicate description.

[0166] In an exemplary embodiment of the communication system 800, TRP A 801, which acts as a reference TRP, can send information about its CSI-RS transmission time and transmission mode to other TRPs, thereby allowing all TRPs to transmit CSI-RS simultaneously. In addition, based on the information exchanged between TRPs, each TRP communicating with the terminal 803 can configure an appropriate beam switching period to measure the performance of all beam combinations. Subsequently, the terminal 803 can measure the performance of each beam combination sent by TRP A 801 and TRP B 802, report the results to TRP A 801, which acts as a reference TRP, and TRP A 801 can select the best beam for the MTRP environment based on the reported information. Figure 8 It shows that each TRP communicating with terminal 803 is based on Figure 5 or Figure 7b The process of assigning a combination index to each beam combination by identifying all beam combinations. Figure 9a and Figure 9bA process is shown in which the terminal 803 measures the SINRs of the beams transmitted by TRP A 801 and TRP B 802 at UE panel A and UE panel B, respectively, and reports the measured SINRs to TRP A 801, which acts as a reference TRP. In this case, when TRP A 801 selects the best beam for the MTRP environment based on the information reported by the terminal 803, TRP B 802 can send its SINR threshold to the terminal 803 via a backhaul between the TRP or base stations connected to the TRP or via the terminal 803 as an intermediate repeater to ensure that the performance of the communication link between TRP B 802 and UE panel B meets a certain level. Fig.10a and Fig.10b 801 selects the best beam combination for the MTRP environment based on the performance of its own beam and the beam of TRP B 802 (measured by the terminal 803 for each beam combination). In summary, the previous process serves as a preliminary step for configuring synchronized CSI-RS transmission for each TRP and setting appropriate beam switching time in the joint beam adjustment process for the MTRP environment. However, Figures 8 to 10a and Fig.10b The process may correspond to the following process: each TRP sends a candidate beam through CSI-RS, the terminal 803 measures the performance of each beam combination, and finally selects the best beam combination for the MTRP environment based on these measurements with reference to the TRP (TRP A 801). Figure 8 The process in and subsequent processes can be as follows: the SINR thresholds of all TRPs and the SINR values ​​of all beam combinations of all TRPs are sent to the reference TRP which is TRP A 801, and then TRP A801 ​​comprehensively evaluates the performance of all TRPs in the MTRP environment, and considers the combined performance of all TRPs to select the best beam for all TRPs and terminal 803.

[0167] In the eighth exemplary embodiment of the beam management method in the communication system, TRP A 801 may perform a beam combination index configuration operation (S831). TRP B 802 may perform a beam combination index configuration operation (S832). TRP A 801 may send information about the beam combination index configured in step S831 to TRP A 801 (S831).

[0168] Specifically, TRP A 801 and TRP B 802 can be connected by using Figure 5 or Figure 7b The process of assigning a combination index to each beam combination and sending the result to the terminal 803 is performed for all beam combinations identified by the process. The above process may be performed the same as or similar to that in Table 10, for example.

[0169] [Table 10]

[0170] Combined index (4 bits) TRP A beam TRP B beam #1(0000) TRP Beam #A-1 TRP Beam #B-1 #2(0001) TRP Beam #A-1 TRP Beam #B-2 #3(0010) TRP Beam #A-1 TRP Beam #B-3 … … … #5(0100) TRP Beam #A-1 TRP Beam #B-5 #6(0101) TRP Beam #A-2 TRP Beam #B-1 … … … #10(1001) TRP Beam #A-2 TRP Beam #B-5 #11(1010) TRP Beam #A-3 TRP Beam #B-1 … … … #15(1110) TRP Beam #A-3 TRP Beam #B-5

[0171] All TRPs communicating with the terminal 803 may determine the total number of beam combinations that can be formed when communicating with the terminal 803 based on information about the number of candidate beams of other TRPs, and all TRPs may calculate how many bits are allocated to represent each beam combination based on this. For example, when the total number of beam combinations is n, ceil(log 2 n) bit (1 bit when n=1). Figure 8 FIG. 8 shows an example in which the total number of beam combinations that can be formed by TRP A 801 and TRP B 802 is 15, and thus 4 bits are allocated to represent each beam combination. Since the two TRPs know the number of candidate beams of each other, they can form beam combinations that are similar to the beam combinations of FIG. Figure 8 If the number of candidate beams that can be used by the terminal 803 in the same situation is 2, the total number of beam combinations that can be formed by TRP A 801, TRP B 802 and the terminal 803 may be 30. Figure 8 In FIG. 1 , TRP beam #AX and TRP beam #BY represent the Xth beam and the Yth beam transmitted by TRP A 801 and TRP B 802, respectively, during the joint beam adjustment process. Figure 8 The process is explained from the perspective of TRP A 801, then TRP A 801 can assign combination indexes of 1 to 5 to the candidate beams used by TRP A for the first time in the joint beam adjustment process, assign combination indexes of 6 to 10 to the candidate beams used by TRP A for the second time in the joint beam adjustment process, and assign combination indexes of 11 to 15 to the candidate beams used by TRP A for the third time. Therefore, TRP A can take into account the candidate beams of other TRPs to assign multiple combination indexes to its own candidate beams respectively, so as to identify which of its own candidate beams have been selected when a specific beam combination is finally selected. In addition, the process considers the case where each of UE panel A and UE panel B has one beam, but it can be extended to the case where each panel has two or more beams. Therefore, when a specific beam combination is finally selected through the joint beam adjustment process, each TRP can identify the best beam through the mapping relationship between the combination index and the beam. TRP A 801 can send information about the beam combination of the two TRPs to the terminal 803 through new RRC signaling. In summary, Figure 8The process can be considered as the following process: assigning combination indexes to all possible beam combinations in each TRP and sending information about the combination indexes to the terminal 803, so as to exchange the performance of each beam combination with the terminal 803 in the subsequent joint beam adjustment process, and determine which candidate beam the selected combination corresponds to.

[0172] Figure 9a and Figure 9b is a sequence diagram for describing the ninth exemplary embodiment and the tenth exemplary embodiment of the beam management method in the communication system.

[0173] like Figure 9a and Figure 9b As shown, the communication system 900 may include one or more TRPs and one or more terminals. For example, the communication system 900 may include TRP A 901, TRP B 902, and terminal 903. In the communication system 900, TRP A 901 and TRP B 902 may be connected to the same base station. Alternatively, in the communication system 900, TRP A 901 and TRP B 902 may be connected to different base stations. TRP A 901 and TRP B 902 may support the same terminal 903. In the following, in reference to Figure 9a and Figure 9b In the ninth exemplary embodiment and the tenth exemplary embodiment describing the beam management method in the communication system, the Figures 1 to 8 Description of duplicate description.

[0174] refer to Figure 9a In the ninth exemplary embodiment of the beam management method in the communication system, TRP B 902 may send information about a first threshold (e.g., an SINR threshold) to TRP A 901 (S941). Terminal 903 may report a first measurement value (e.g., an SINR value) of a signal received from TRP A 901 and TRP B 902 to TRP A 901 (S942).

[0175] refer to Figure 9b In the tenth exemplary embodiment of the beam management method in the communication system, TRP B 902 may send information about a first threshold value (e.g., an SINR threshold value) to the terminal 903 (S944). The terminal 903 may report the information about the first threshold value received from TRP B 902 and a first measurement value (e.g., an SINR value) of the signals received from TRP A 901 and TRP B 902 to TRP A 901 (S945).

[0176] The information reported in step S942 or step S945 may have a format that is the same as or similar to, for example, Table 11.

[0177] [Table 11]

[0178] Combined index (4 bits) SINR value (UE panel A) SINR value (UE panel B) #1(0000) SINR_79 SINR_75 #2(0001) SINR_107 SINR_60 #3(0010) SINR_62 SINR_98 … … … #14(1101) SINR_88 SINR_100 #15(1110) SINR_95 SINR_102

[0179] Figure 9a and Figure 9bA process is shown in which the terminal 903 measures the SINR value of each beam combination sent by TRP A 901 at UE panel A and UE panel B and reports the SINR value to TRP A 901 acting as a reference TRP. In the present invention, the best beam is selected based on the SINR value of the beam combination, but the process of selecting the best beam according to other criteria may also be considered. For example, the best beam may be selected by considering the delay requirement of the terminal 903 or the mobility of the terminal 903. When considering the delay requirement of the terminal 903, a beam that supports higher performance in terms of user experience data rate may be selected, and when considering the mobility of the terminal 903, a beam that can send data to the terminal 903 over a longer period of time based on UE mobility or trajectory may be selected. In addition, when considering channel stability, a beam with the smallest change in the value of the measured SINR may also be selected. The process of reporting the performance of two TRPs to TRPA 901 is used to select the best beam combination for the MTRP environment by considering the performance of the two TRPs in TRP A 901 acting as a reference TRP. In order for TRP A 901 to consider the performance of both TRPs, TRP B 902 may send its SINR threshold to TRP A 901 via a backhaul between TRPs or between base stations connected to the TRPs or via the terminal 903, so that when TRP A 901 finally selects a beam combination, the selected beam combination may ensure that the communication link between itself and the terminal 903 has a certain level or higher performance. When a backhaul between TRPs or between base stations connected to the TRPs is available, information about the SINR threshold may be sent from TRP B 902 to TRP A 901 via a backhaul between TRPs or between base stations connected to the TRPs. On the other hand, in the case where a backhaul between TRPs or between base stations connected to the TRPs is not available, if TRP B 902 is connected to the same base station as the base station to which TRP A 901 is connected, TRP B 902 may send information about its SINR threshold to the terminal 903 through SIB, DCI or other new RRC signaling. If TRP B 902 is connected to a base station different from the base station to which TRP A 901 is connected, TRP B 902 may send information about its SINR threshold through SIB, DCI, Msg2, MsgB, or other new SRB3 signaling. Thereafter, the terminal 903 may send information about the received SINR threshold of TRP B 902 to TRP A 901 through UCI, UE assistance information, or other new RRC signaling. In addition, Figure 9a and Figure 9b The combined index in Figure 8The combination index of each beam combination configured in , and the SINR value (at UE panel A) represents the SINR value of the communication link between TRP A 901 and UE panel A when the terminal 903 receives the beam corresponding to the specific beam combination index from TRP A 901 and TRP B 902. Similarly, the SINR value (at UE panel B) represents the SINR value of the communication link between TRP B 902 and UE panel B. The terminal 903 can Figure 9a and Figure 9b In the process of sending the SINR values ​​at UE panel A and UE panel B to TRP A 901, thereafter, TRP A 901 can Fig.10a and Fig.10b In the process, the best beam combination is selected for the MTRP environment based on the performance of each communication link received from the terminal 903. Figure 9a and Figure 9b An example is shown in which the SINR value is regarded as a criterion for selecting a beam combination. TRP A 901 may indicate which criterion will be utilized as the TRP selection criterion through SIB or other new RRC signaling. Terminal 903 may measure the performance of the communication links established with TRP A 901 and TRP B 902, respectively, and then send information about the combination index # and the SINR value of the communication link established with TRP A 901 to TRP A 901 through the CSI-RS reporting process. The process of sending information about the SINR value of the communication link established with TRP B 902 (instead of TRP A 901) may be performed as follows: TRP A 901 may send information indicating reporting the performance of the communication link between TRP B 902 and terminal 903 to terminal 903 through a UEInformationRequest message as RRC signaling. Terminal 903 may receive the information and then send information about the SINR value of the communication link between TRP B 902 and UE panel B to TRP A 901 through a UEInformationResponse message. In addition, TRP A 901 may send information indicating the performance of the communication link between TRP B 902 and terminal 903 to terminal 903 via SIB or new RRC signaling, and terminal 903 may utilize measurement reports or UE assistance information as a response to the instruction, or new RRC signaling may be defined for such a purpose.

[0180] Fig.10a and Fig.10b is a sequence diagram for describing an eleventh exemplary embodiment and a twelfth exemplary embodiment of a beam management method in a communication system.

[0181] like Fig.10a and Fig.10b As shown, the communication system 1000 may include one or more TRPs and one or more terminals. For example, the communication system 1000 may include TRP A 1001, TRP B 1002, and terminal 1003. In the communication system 1000, TRP A 1001 and TRP B 1002 may be connected to the same base station. Alternatively, in the communication system 1000, TRP A 1001 and TRP B 1002 may be connected to different base stations. TRP A 1001 and TRP B 1002 may support the same terminal 1003. In the following, in reference to Fig.10a and Fig.10b In the eleventh exemplary embodiment and the twelfth exemplary embodiment describing the beam management method in the communication system, the Figures 1 to 9b Description of duplicate description.

[0182] refer to Fig.10a In the eleventh exemplary embodiment of the beam management method in the communication system, TRP A 1001 may select an optimal beam combination (or its index) (S1051). TRP A 1001 may send information of the selected optimal beam combination (or its index) to terminal 1003 (S1052). TRP A 1001 may also send information about the selected optimal beam combination (or its index) to TRP B 1002 (S1053).

[0183] refer to Fig.10b In the twelfth exemplary embodiment of the beam management method in the communication system, TRP A 1001 may select the best beam combination (or its index) (S1055). TRP A 1001 may send information about the selected best beam combination (or its index) to terminal 1003 (S1056). Then terminal 1003 may send information about the best beam combination (or its index) selected by TRP A 1001 to TRP B 1002 (S1057).

[0184] Specifically, Fig.10a and Fig.10b The following process is shown: TRP A 1001 is based on Figure 9a and Figure 9b The process shown selects the best beam combination based on the received SINR values ​​of TRP A 1001 and TRP B 1002 and the SINR threshold of TRP B 1002.

[0185] [Table 12]

[0186]

[0187]

[0188] In Table 12, the combined index is represented in Figure 8 The column corresponding to TRPA 1001 indicates whether the SINR value of the communication link between TRP A 1001 and UE panel A meets the SINR threshold set by TRP A 1001. Similarly, the column corresponding to TRP B 1002 indicates whether the SINR value of the communication link between TRP B 1002 and UE panel B meets the SINR threshold set by TRP B 1002. In the process of finally selecting a beam, TRPA 1001 can first determine whether the SINR value received from terminal 1003 exceeds the SINR threshold specified by the TRP corresponding to the communication link to meet the minimum requirement configured by each TRP. TRP A 1001 can then evaluate whether a particular beam combination meets the SINR thresholds of all communication links, and finally select a beam by considering only those combination indices that meet the criteria. For example, in Fig.10a and Fig.10b In the case of combination index #2, the communication link between TRP A 1001 and UE panel A meets the SINR threshold set by TRP A 1001, but the communication link between TRP B 1002 and UE panel B does not meet the SINR threshold set by TRP B 1002. Therefore, TRP A 1001 can exclude combination index #2 when finally selecting beam combination. Similarly, combination index #3 can be excluded because the communication link between TRP A 1001 and UE panel A does not meet the SINR threshold set by TRP A 1001. Fig.10a and Fig.10b In the example, the combined index #14 and #15 can be considered for the final selection, and according to Figure 9a and Figure 9b , composite index #15 can be selected last because it provides better performance. Fig.10a and Fig.10b In the example, if both combination indexes #14 and #15 meet the SINR thresholds of the two TRPs, but combination index #14 provides better performance for TRP A 1001 and combination index #15 provides better performance for TRP B 1002, then it is also possible to consider selecting a beam combination that provides a higher overall data transmission rate from the perspective of terminal 1003. In addition, if the two beam combinations meet the SINR requirements, it is possible to select a beam combination that provides a higher overall data transmission rate from the perspective of terminal 1003 based on the above Figure 9a and Figure 9bThe best beam combination is selected based on other criteria mentioned in . For example, when considering the latency requirement of terminal 1003, a beam combination that supports higher performance in terms of user experienced data rate can be selected. When considering the mobility of terminal 1003, a beam combination that can send data to terminal 1003 for a longer time based on UE mobility or trajectory can be selected. In addition, when considering channel stability, a beam combination with a smaller change in SINR value measured in the selected beam combination can be selected. The present invention mainly considers the case where each of UE panel A and UE panel B of terminal 1003 has only one beam, but can also be extended to the case of having two or more beams. Therefore, it is necessary to send information about the last selected combination index to terminal 1003. TRP A 1001 can send the last selected combination index to terminal 1003 through RRC reconfiguration or other new RRC signaling. TRP A 1001 may immediately identify its best beam from the last selected combination index, while TRP B 1002 may need to receive information about the selected combination index from TRP A 1001 via a backhaul between TRPs or between base stations connected to the TRPs or via a terminal 1003. If TRP B 1002 receives the information via a backhaul between TRPs or between base stations connected to the TRPs, TRP A 1001 may send the information to TRP B 1002 via the backhaul. Conversely, if TRP B 1002 receives the information via a terminal 1003, the terminal 1003 may send the information about the combination index received from TRP A 1001 to TRP B 1002. When the terminal 1003 sends the information about the last selected beam combination index to TRP B 1002, if TRP B 1002 is connected to the same base station as the base station to which TRP A 1001 is connected, the terminal 1003 may send the information about the last selected beam combination index to TRP B 1002 through UCI, UE assistance information or other new RRC signaling. If TRP B 1002 is connected to a base station different from the base station to which TRP A 1001 is connected, the terminal 1003 may send the information about the last selected beam combination index to TRP B 1002 through Msg1 or MsgA or through UE assistance information or other new SRB3 signaling. Thereafter, as Figure 8 As described above, TRP B 1002 can determine which beam is selected from its candidate beams through the joint beam coordination process based on the last selected combination index. Through this process, all TRPs and terminal 1003 can subsequently communicate using the best beam selected through the joint beam coordination process.

[0189] Fig.11 is a sequence diagram for describing a first exemplary embodiment of a beam adjustment method in a communication system.

[0190] like Fig.11 As shown, the communication system 1100 can be used with reference Figure 3 , Figure 4 , Figure 5 , Figure 8 , Figure 9a and Fig.10a The communication systems 300, 400, 500, 800, 900, and 1000 described are the same or similar. The communication system 1100 may include one or more TRPs and one or more terminals. For example, the communication system 1100 may include TRP A 1101, TRP B 1102, and terminal 1103. In the communication system 1100, TRP A 1101 and TRP B 1102 may be connected to the same base station. TRP A 1101 and TRP B 1102 may perform mutual information transmission and reception via a backhaul, etc. TRP A 1101 and TRP B 1102 may support the same terminal 1103. In the following, in reference to Fig.11 In the first exemplary embodiment of the beam adjustment method in the communication system, the reference Figures 1 to 10b Description of duplicate description.

[0191] TRP A 1101 may perform a beam candidate group configuration operation (S1111). TRP B 1102 may perform a beam candidate group configuration operation (S1112). The operations according to steps S1111 and S1112 may be the same as those according to reference Figure 3 The operations of steps S311 and S312 are described to be the same or similar.

[0192] TRP A 1101 may transmit information on a transmission time, a transmission mode, and similar details of a first reference signal (S1121). TRP B 1102 may receive information on a transmission time, a transmission mode, and similar details of a first reference signal transmitted by TRP A 1101 (S1121). The operation according to step S1121 may be similar to the operation according to step S1122. Figure 4 The operation of step S421 described is the same or similar.

[0193] TRP A 1101 and TRP B 1102 may exchange information about TRP IDs and the number of candidate beams with each other (S1124). Terminal 1103 may send information about the number of its candidate beams to TRP A 1101 and TRP B 1102 (S1126, S1127). TRP A 1101 and TRP B 1102 may each set their own beam switching period (S1128, S1129). The operations according to steps S1124 to S1129 may be the same as those according to reference 1. Figure 5 The operations of steps S524 to S529 described are the same or similar.

[0194] The TRP A 1101 may perform a beam combination index configuration operation (S1131). The TRP B 1102 may perform a beam combination index configuration operation (S1132). The TRP A 1101 may transmit information about the beam combination index configured in step S1131 to the TRP B 1102 (S1133). The operations according to steps S1131 to S1134 may be the same as those according to the reference Figure 8 The operations of steps S831 to S834 described are the same or similar.

[0195] TRP B 1102 may transmit information about a first threshold value (e.g., an SINR threshold value) to TRP A 1101 (S1141). Terminal 1103 may report a first measurement value (e.g., an SINR value) of a signal received from TRP A 1101 and TRP B 1102 to TRP A 1101 (S1142). The operations according to steps S1141 to S1142 may be similar to those according to reference 1. Figure 9a The operations of steps S941 to S942 described are the same or similar.

[0196] TRP A 1101 may select an optimal beam combination (or its index) (S1151). TRP A 1101 may send information of the selected optimal beam combination (or its index) to terminal 1103 (S1152). TRP A 1101 may send information of the selected optimal beam combination (or its index) to TRP B 1102 (S1153). The operations according to steps S1151 to S1153 may be the same as those according to reference 1. Fig.10a The operations of steps S1051 to S1053 described are the same or similar.

[0197] Based on at least some of the operations from steps S1111 to S1150, beam adjustment for beam-based communication between TRP A 1101, TRP B 1102, and terminal 1103 may be performed. TRP A 1101, TRP B 1102, and terminal 1103 may perform beam-based communication based on the best beam combination (or its index) selected in step S1151 (S1160). That is, TRP A 1101, TRP B 1102, and terminal 1103 may perform mutual communication using beams constituting the selected best beam combination.

[0198] The operation method of the terminal 1103 according to the first exemplary embodiment of the beam adjustment method in the communication system may include the steps of transmitting information about one or more candidate beams of the terminal 1103 to TRP A 1101 and TRP B 1102, receiving information about one or more beam combinations from TRP A 1101, performing a measurement operation on a first signal corresponding to each of the one or more beam combinations received from TRP A 1101 and TRP B 1102, transmitting information about a first measurement value of each beam combination obtained based on the measurement operation to TRP A 1101, and receiving information of a first beam combination selected from the one or more beam combinations of TRP A 1101 based on the first measurement value of each beam combination. Each of the one or more beam combinations may be a combination of one beam of the candidate beams of TRP A 1101, one beam of the candidate beams of TRP B 1102, and one beam of the candidate beams of the terminal 1103.

[0199] The step of performing the measurement operation may include the step of receiving the first signal transmitted from TRP A 1101 and TRP B 1102 and the step of performing the measurement operation on the received first signal. In the step of receiving the first signal, the reception time of the first signal transmitted from TRP A 1101 and the reception time of the first signal transmitted from TRP B 1102 may be made consistent.

[0200] In the step of receiving the first signal, the first signal sent from TRP A 1101 can be received based on a first time period configured according to information of one or more candidate beams of TRP A 1101, and the second signal sent from TRP B 1102 can be received based on a second time period configured according to information of one or more candidate beams of TRP B 1102.

[0201] The first measurement value may be a signal to interference plus noise ratio (SINR) value of the first signal. The step of performing the measurement operation may include a step of receiving a first signal sent from TRP A 1101 through a first panel of a terminal 1103 corresponding to TRP A 1101, a step of receiving a first signal sent from TRP B 1102 through a second panel of a terminal 1103 corresponding to TRP B 1102, a step of obtaining a first measurement value for each of the received first signals, and a step of mapping the obtained first measurement value to each of one or more beam combinations.

[0202] The first beam combination selected by TRP A 1101 may include at least a first beam from one or more candidate beams of TRP A 1101, a second beam from one or more candidate beams of TRP B 1102, and a third beam from one or more candidate beams of terminal 1103. The operating method of terminal 1103 may further include: after receiving the information of the first beam combination, performing a step of beam-based communication with TRP A 1101 and TRP B 1102 based on the beams constituting the first beam combination selected by TRP A 1101.

[0203] The first beam combination selected by TRP A 1101 may include at least a first beam from one or more candidate beams of TRP A 1101, a second beam from one or more candidate beams of TRP B 1102, and a third beam corresponding to TRP A 1101 and a fourth beam corresponding to TRP B 1102 from one or more candidate beams of terminal 1103. The operating method of terminal 1103 may further include: after receiving the information of the first beam combination, performing a step of beam-based communication with TRP A 1101 and TRPB 1102 based on the beams constituting the first beam combination selected by TRP A 1101.

[0204] The operating method of TRP A 1101 according to the first exemplary embodiment of the beam adjustment method in a communication system may include a step of configuring one or more candidate beams of TRP A 1101, a step of receiving information about one or more candidate beams of TRPB 1102 from TRP B 1102, a step of receiving information about one or more candidate beams of terminal 1103 from terminal 1103, a step of configuring one or more beam combinations, a step of sending information about one or more beam combinations to terminal 1103, a step of receiving information about one or more first measurement values ​​of one or more first signals corresponding to each of the one or more beam combinations from terminal 1103, a step of selecting a first beam combination from the one or more beam combinations based on the information of the first measurement values, and a step of sending the information of the selected first beam combination to terminal 1103 and TRP B 1102. Each combination of one or more beam combinations may be a combination of one beam of the candidate beam of TRP A 1101, one beam of the candidate beam of TRP B 1102, and one beam of the candidate beam of terminal 1103.

[0205] The operating method of TRP A 1101 may further include: before the step of configuring one or more beam combinations, a step of configuring a beam switching period for the beam sending the first signal in TRP A 1101 based on information about the transmission time, information about one or more candidate beams of terminal 1103, and information about one or more candidate beams of TRP B 1102.

[0206] The operating method of TRP A 1101 may further include: before the step of configuring one or more beam combinations, the step of sending information about the transmission time of one or more first signals transmitted by TRP A 1101 to TRP B 1102. The information about the transmission time may be used to adjust the transmission time of one or more first signals transmitted by TRP B 1102.

[0207] The first measurement value may be an SINR value of the first signal, and the step of selecting a first beam combination may include the step of identifying information about a first threshold received in advance from a second communication node, identifying information about one or more first measurement values ​​received from terminal 1103, and selecting the first beam combination from one or more beam combinations based on the information about the first threshold and the information about the one or more first measurement values.

[0208] The first beam combination may include at least a first beam from one or more candidate beams of TRP A 1101, a second beam from one or more candidate beams of TRP B 1102, and a third beam from one or more candidate beams of terminal 1103. The operating method of TRP A 1101 may further include the step of performing beam-based communication with terminal 1103 based on the first beam and the third beam from the beams constituting the first beam combination.

[0209] The first beam combination may include at least a first beam from one or more candidate beams of TRP A 1101, a second beam from one or more candidate beams of TRP B 1102, and a third beam corresponding to TRP A 1101 and a fourth beam corresponding to TRP B 1102 from one or more candidate beams of terminal 1103. The operating method of TRP A 1101 may further include the step of performing beam-based communication with terminal 1103 based on the first beam and the third beam from the beams constituting the first beam combination.

[0210] Fig.12 is a sequence diagram for describing a second exemplary embodiment of a beam adjustment method in a communication system.

[0211] like Fig.12 As shown, the communication system 1200 can be used with reference Figure 3 , Figure 4 , Figure 5 , Figure 8 , Figure 9a and Fig.10a The communication system 300, the communication system 400, the communication system 500, the communication system 800, the communication system 900 and the communication system 1000 described are the same or similar. The communication system 1200 may include one or more TRPs and one or more terminals. For example, the communication system 1200 may include a TRP A 1201, a TRP B 1202 and a terminal 1203. In the communication system 1200, the TRP A 1201 and the TRP B 1202 may be connected to different base stations. The TRP A 1201 and the TRP B 1202 may support the same terminal 1203. The TRP A 1201 and the TRP B 1202 may perform mutual information transmission and reception via the terminal 1203. In the following, in reference to Fig.12 In the second exemplary embodiment of the beam adjustment method in the communication system, the reference Figures 1 to 11 Description of duplicate description.

[0212] TRP A 1201 may perform a beam candidate group configuration operation (S1211). TRP B 1202 may perform a beam candidate group configuration operation (S1212). The operations according to steps S1211 and S1212 may be the same as those according to reference Figure 3 The operations of steps S311 and S312 are described to be the same or similar.

[0213] TRP A 1201 may transmit information about its TRP ID (eg, TRP ID_A) and information about the transmission time, transmission mode, etc. of the first reference signal to the terminal 1203 (S1221). The operation according to step S1221 may be similar to the operation according to the reference signal. Figure 6a The operation of step S621 described is the same or similar.

[0214] Terminal 1203 may send the information received in step S1221, specifically information about TRPID and information about the transmission time and transmission mode of the first reference signal of TRPA 1201, to TRPB 1202 (S1222). The operation according to step S1222 may be similar to the operation according to the reference signal. Figure 6b The operation of step S622 described is the same or similar.

[0215] TRP A 1201 may send information about its TRP ID and information about the number of its candidate beams to the terminal 1203 (S1224). TRP B 1202 may send information about its TRP ID and the number of its candidate beams to the terminal 1203 (S1225). The operations according to steps S1224 to S1225 may be the same as those according to reference 1. Figure 7a The operations of steps S724 to S725 described are the same or similar.

[0216] The terminal 1203 may send the information received in step S1225, specifically information about the TRP ID of the TRP B 1202 and the number of candidate beams, to the TRP A 1201 (S1226). The terminal 1203 may send the information received in step S1224, specifically information about the TRP ID of the TRP A 1201 and the number of candidate beams, to the TRP B 1202 (S1227). The TRP A 1201 and the TRP B 1202 may each set their own beam switching period (S1228, S1229). The operations according to steps S1226 to S1229 may be the same as those according to the reference 1. Figure 7b The operations of steps S726 to S729 described are the same or similar.

[0217] The TRP A 1201 may perform a beam combination index configuration operation (S1231). The TRP B 1202 may perform a beam combination index configuration operation (S1232). The TRP A 1201 may transmit information about the beam combination index configured in step S1231 to the TRP B 1202 (S1233). The operations according to steps S1231 to S1234 may be the same as those according to the reference Figure 8 The operations of steps S831 to S834 described are the same or similar.

[0218] TRP B 1202 may transmit information about the first threshold (e.g., SINR threshold) to terminal 1203 (S1244). Terminal 1203 may report information about the first threshold received from TRP B 1202 and information about the first measurement value (e.g., SINR value) of the signal received from TRP A 1201 and TRPB 1202 to TRP A 1201 (S1245). The operations according to steps S1244 to S1245 may be similar to those according to reference 1. Figure 9b The operations of steps S944 to S945 described are the same or similar.

[0219] TRP A 1201 may select the best beam combination (or its index) (S1255). TRP A 1201 may send information of the selected best beam combination (or its index) to terminal 1203 (S1256). Terminal 1203 may send information of the best beam combination (or its index) selected by TRP A 1201 to TRP B 1202 (S1257). The operations according to steps S1255 to S1257 may be the same as those according to reference 1. Fig.10b The operations of steps S1055 to S1057 described are the same or similar.

[0220] Based on at least some of the operations from steps S1211 to S1250, beam adjustment for beam-based communication between TRP A 1201, TRP B 1202, and terminal 1203 may be performed. TRP A 1201, TRP B 1202, and terminal 1203 may perform beam-based communication based on the best beam combination (or its index) selected in step S1251 (S1260). That is, TRP A 1201, TRP B 1202, and terminal 1203 may perform mutual communication using beams constituting the selected best beam combination.

[0221] An operating method of a terminal 1203 according to a second exemplary embodiment of a beam adjustment method in a communication system may include: a step of receiving information about one or more candidate beams of each of TRP A 1201 and TRP B 1202 from TRP A 1201 and TRP B 1202, a step of sending information about one or more candidate beams of TRP B 1202 to TRP A 1201, a step of sending information about one or more candidate beams of TRP A 1201 to TRP B 1202, a step of receiving information about one or more beam combinations from TRP A 1201, a step of sending information about a first measurement value of each beam combination corresponding to each of the one or more beam combinations to TRP A 1201, and a step of receiving information about a first beam combination selected by TRP A 1201 based on the sent information about the first measurement value of each beam combination. Each of the one or more beam combinations may be configured as a combination of at least one of the candidate beams of TRP A 1201 and one of the candidate beams of TRP B 1202.

[0222] The step of transmitting information about the first measurement value of each beam combination may include: the step of receiving a first signal corresponding to each of one or more beam combinations transmitted from each of TRP A 1201 and TRP B 1202, the step of performing a measurement operation on the received first signal, and the step of transmitting information about the first measurement value of each beam combination obtained based on at least the measurement operation to TRP A 1201. In the step of receiving the first signal, a reception time of the first signal transmitted from TRP A 1201 and a reception time of the first signal transmitted from TRP B 1202 may be made consistent.

[0223] In the step of receiving a first signal, the first signal sent from TRP A 1201 can be received based on a first time period configured according to information about one or more candidate beams about TRP A 1201, and the second signal sent from TRP B 1202 can be received based on a second time period configured according to information about one or more candidate beams about TRPB 1202.

[0224] The step of sending information about the first measurement value of each beam combination may include: the step of receiving information about a first threshold corresponding to the first measurement value from TRP B 1202, and the step of sending the information about the first threshold received from TRP B 1202 and the information about the first measurement value of each beam combination to TRP A 1201.

[0225] The first measurement value may be an SINR value of the first signal, and the step of sending information about the first measurement value of each beam combination may include: a step of receiving a first signal sent from TRP A 1201 through a first panel of a terminal 1203 corresponding to TRP A 1201, a step of receiving a first signal sent from TRP B 1202 through a second panel of a terminal 1203 corresponding to TRP B, a step of obtaining a first measurement value for each of the received first signals, a step of mapping the obtained first measurement value to each of one or more beam combinations to obtain information about the first measurement value of each beam combination, and a step of sending at least information about the first measurement value of each beam combination to TRP A 1201.

[0226] The operating method of terminal 1203 may further include: before the step of receiving information about one or more candidate beams of each of TRP A 1201 and TRP B 1202, the step of receiving information about the transmission time of the first signal of TRP A 1201 from TRP A 1201 and sending the information about the transmission time of the first signal of TRP A 1201 to TRPB 1202.

[0227] The operating method of the terminal 1203 may further include: before the step of receiving the information about the one or more beam combinations, the step of sending information about the one or more candidate beams of the terminal 1203 to the TRP A 1201. The first beam combination selected by the TRP A 1201 may include: a first beam from the one or more candidate beams of the TRP A 1201, a second beam from the one or more candidate beams of the TRP B 1202, and a third beam from the one or more candidate beams of the terminal 1203.

[0228] The operation method of the terminal 1203 may further include: before the step of receiving the information about the one or more beam combinations, the step of sending information about the one or more candidate beams of the terminal 1203 to the TRP A 1201. The first beam combination selected by the TRP A 1201 may include at least: a first beam from the one or more candidate beams of the TRP A 1201, a second beam from the one or more candidate beams of the TRP B 1202, and a third beam corresponding to the TRP A 1201 and a fourth beam corresponding to the TRP B 1202 from the one or more candidate beams of the terminal 1203.

[0229] The operating method of the terminal 1203 may further include: after the step of receiving information about the first beam combination, the step of sending the received information about the first beam combination to TRP B 1202.

[0230] The operation method of TRP A 1201 according to the second exemplary embodiment of the beam adjustment method in the communication system may include: a step of configuring one or more candidate beams of TRP A 1201, a step of transmitting information about the one or more candidate beams of TRP A 1201 to a terminal 1203, a step of receiving information about one or more candidate beams of TRP B 1202 from the terminal 1203, a step of configuring one or more beam combinations, a step of transmitting information about the one or more beam combinations to the terminal 1203, a step of receiving information about one or more first measurement values ​​of one or more first signals corresponding to each of the one or more beam combinations from the terminal 1203, a step of selecting a first beam combination from the one or more beam combinations based on the information about the first measurement values, and a step of transmitting information about the selected first beam combination to the terminal 1203. Each of the one or more beam combinations may be configured as a combination of one beam from the one or more candidate beams of TRP A 1201 and one beam from the one or more candidate beams of TRP B 1202.

[0231] The operating method of TRPA 1201 may further include: before the step of sending information about one or more candidate beams, the step of sending information about the transmission time of one or more first signals of TRPA 1201 to the terminal 1203.

[0232] The operating method of TRP A 1201 may further include: before the step of configuring one or more beam combinations, the step of sending information about the transmission time of one or more first signals sent by TRP A 1201 to terminal 1203, and the information about the transmission time can be used to adjust the transmission time of one or more first signals sent by TRP B 1202.

[0233] The first measurement value may be an SINR value of the first signal, and the information related to the one or more first measurement values ​​includes: information about a first threshold value corresponding to the one or more first measurement values ​​and information about the first measurement value of each beam combination. The step of selecting the first beam combination may include: a step of identifying information about a second threshold value corresponding to the one or more first measurement values ​​predetermined by TRP A 1201, and a step of selecting the first beam combination from the one or more beam combinations based on the information about the first threshold value, the information about the second threshold value, and the information about the first measurement value of each beam combination.

[0234] The operation method of TRP A 1201 may further include: before the step of transmitting the information about the one or more beam combinations, the step of receiving information about one or more candidate beams of terminal 1203 from terminal 1203. The first beam combination may include: a first beam from one or more candidate beams of TRP A 1201, a second beam from one or more candidate beams of TRP B 1202, and a third beam from one or more candidate beams of terminal 1203.

[0235] The operation method of TRP A 1201 may further include: before the step of transmitting the information about the one or more beam combinations, the step of receiving information about one or more candidate beams of terminal 1203 from terminal 1203. The first beam combination may include: a first beam from the one or more candidate beams from TRP A 1201, a second beam from the one or more candidate beams from TRP B 1202, a third beam corresponding to TRP A 1201 from the one or more candidate beams from terminal 1203, and a fourth beam corresponding to TRP B 1202.

[0236] Fig.13is a flow chart for describing a first exemplary embodiment of a beam adjustment method in a communication system.

[0237] like Fig.13 As shown, the communication system can be compared with the reference Figure 3 , Figure 4 , Figure 5 , Figure 8 , Figure 9a and Fig.10a The communication system 300, the communication system 400, the communication system 500, the communication system 800, the communication system 900 and the communication system 1000 described are the same or similar. The communication system may include one or more TRPs and one or more terminals. For example, the communication system may include TRPA, TRP B and a terminal. In the communication system, TRP A and TRP B may be connected to the same base station. TRP A and TRP B may perform mutual information transmission and reception via a backhaul, etc. TRP A and TRP B may support the same terminal. In the following, in reference to Fig.13 In the first exemplary embodiment of the beam adjustment method in the communication system, the reference Figures 1 to 12 Description of duplicate description.

[0238] In the first exemplary embodiment of the beam adjustment method in the communication system, TRP A and TRP B may perform a beam candidate group configuration process (S1310). The operation according to step S1310 may be similar to the operation according to reference Figure 3 The operations of the first exemplary embodiment of the beam management method in the communication system described are the same or similar.

[0239] TRP A, TRP B and the terminal may perform a beam switching period configuration process (S1320). The beam switching period configuration process of step S1320 may be performed based on information exchange between TRPs via a backhaul or similar means. The operation according to step S1320 may be similar to the operation according to reference Figure 4 and Figure 5 The operations of the second exemplary embodiment and the third exemplary embodiment of the described beam management method in a communication system are the same or similar.

[0240] TRP A and TRP B may each configure a beam combination index, and TRP A may send information of the configured beam combination index to the terminal, etc. (S1330). The operation according to step S1330 may be similar to the operation according to reference Figure 8 The operations of the eighth exemplary embodiment of the beam management method in the communication system described are the same or similar.

[0241] TRP A, TRP B, and the terminal may perform a process for reporting a TRP-specific measurement value (eg, SINR value) (S1340). In step S1340, the terminal may report the TRP-specific measurement value to TRP A. The operation according to step S1340 may be similar to the operation according to reference Figure 9a The operations of the ninth exemplary embodiment of the beam management method in a communication system described are the same or similar.

[0242] TRP A may select the best beam combination and transmit information of the selected best beam combination (S1350). In step S1350, TRP A may transmit information of the selected best beam combination to the terminal and TRP B. The operation according to step S1350 may be similar to the operation according to reference 1. Fig.10a The operations of the eleventh exemplary embodiment of the beam management method in a communication system described are the same or similar.

[0243] Based on at least some of the operations from steps S1310 to S1350, beam adjustment for beam-based communication between TRP A, TRP B, and the terminal may be performed. TRP A, TRP B, and the terminal may perform beam-based communication based on the optimal beam combination (or its index) selected in step S1350.

[0244] Fig.14 is a flow chart for describing a second exemplary embodiment of a beam adjustment method in a communication system.

[0245] like Fig.14 As shown, the communication system can be compared with the reference Figure 3 , Figure 4 , Figure 5 , Figure 8 , Figure 9a and Fig.10a The communication system 300, the communication system 400, the communication system 500, the communication system 800, the communication system 900 and the communication system 1000 described are the same or similar. The communication system may include one or more TRPs and one or more terminals. For example, the communication system may include TRPA, TRP B and a terminal. In the communication system, TRP A and TRP B may be connected to the same base station. TRP A and TRP B may perform mutual information transmission and reception via a backhaul, etc. TRP A and TRP B may support the same terminal. In the following, in reference to Fig.14 In the second exemplary embodiment of the beam adjustment method in the communication system, the reference Figures 1 to 13 Description of duplicate description.

[0246] In the second exemplary embodiment of the beam adjustment method in the communication system, TRP A and TRP B may perform a beam candidate group configuration process (S1410). The operation according to step S1410 may be similar to the operation according to reference Figure 3 The operations of the first exemplary embodiment of the beam management method in the communication system described are the same or similar.

[0247] TRP A, TRP B and the terminal may perform a beam switching period configuration process (S1420). The beam switching period configuration process of step S1420 may be performed by the terminal based on information exchange between TRPs. The operation according to step S1420 may be the same as that according to reference Figure 6a , Figure 6b , Figure 7a and Figure 7b The operations of the fourth exemplary embodiment, the fifth exemplary embodiment, the sixth exemplary embodiment, and the seventh exemplary embodiment of the described beam management method in a communication system are the same or similar.

[0248] TRP A and TRP B may each configure a beam combination index, and TRP A may send information of the configured beam combination index to the terminal, etc. (S1430). The operation according to step S1430 may be similar to the operation according to reference Figure 8 The operations of the eighth exemplary embodiment of the beam management method in the communication system described are the same or similar.

[0249] TRP A, TRP B, and the terminal may perform a process for reporting a TRP-specific measurement value (eg, SINR value) (S1440). In step S1440, the terminal may report the TRP-specific measurement value to TRP A. The operation according to step S1440 may be similar to the operation according to reference Figure 9b The operations of the tenth exemplary embodiment of the beam management method in a communication system described are the same or similar.

[0250] TRP A may select the best beam combination and transmit information of the selected best beam combination (S1450). In step S1450, TRP A may transmit information of the selected best beam combination to the terminal and TRP B. The operation according to step S1450 may be similar to the operation according to reference 1. Fig.10b The operations of the twelfth exemplary embodiment of the beam management method in a communication system are the same or similar as described.

[0251] Based on at least some of the operations from steps S1410 to S1450, beam adjustment for beam-based communication between TRP A, TRP B, and the terminal may be performed. TRP A, TRP B, and the terminal may perform beam-based communication based on the optimal beam combination (or its index) selected in step S1450.

[0252] refer to Figures 11 to 14 The exemplary embodiments described are based on an environment where CSI-RS is used as a reference signal and TRP selects the best beam combination (i.e., a downlink (DL) environment). However, this is merely an example for ease of description, and the exemplary embodiments of the beam management method in a communication system are not limited thereto. For example, referring to Figures 3 to 14 At least some of the described exemplary embodiments may be similarly applied or extended in an uplink (UL) environment.

[0253] refer to Figures 11 to 14 The exemplary embodiment described is based on an MTRP environment in which two TPPs (ie, TRP A and TRPB) support a single terminal. However, this is merely an example for ease of description, and the exemplary embodiment of the beam management method in a communication system is not limited thereto. For example, referring to Figures 3 to 14 At least some of the described exemplary embodiments may be similarly applied or extended to situations in which three or more TRPs communicate with a single terminal.

[0254] refer to Figures 11 to 14 The exemplary embodiment described is centered on the case where the terminal has a single candidate beam. However, this is merely an example for ease of description, and the exemplary embodiment of the beam management method in the communication system is not limited thereto. For example, referring to Figures 3 to 14 At least some of the exemplary embodiments described can be similarly applied or extended to the case where the terminal has two or more candidate beams. For example, for each beam that the terminal can form, by measuring the performance of the beam combination formed by TRP A and TRP B, the best beam combination can be determined.

[0255] refer to Figures 11 to 14 The described exemplary embodiment is based on the case where, for the CSI transmission times of two TRPs, TRP A is set as the reference TRP, TRP A sends information about its CSI-RS transmission time and transmission mode to TRP B, and TRP B then makes its CSI-RS transmission time and mode consistent with the CSI-RS transmission time and mode of TRP A. However, this is merely an example for ease of description, and the exemplary embodiment of the beam management method in a communication system is not limited thereto. For example, referring to Figures 3 to 14 At least some of the described exemplary embodiments may be similarly applied or extended to a configuration in which a reference TRP is configured based on a TRP ID (eg, a TRP with a smaller TRP ID may be configured as a reference TRP). Figures 3 to 14 At least some of the described exemplary embodiments may be similarly applied or extended to a configuration in which a reference TRP is configured based on resource utilization (e.g., a TRP with higher resource utilization may be configured as the reference TRP), and a TRP with more available resources may be consistent with the reference TRP in terms of resource utilization. Figures 3 to 14 At least some of the described exemplary embodiments take into account situations where TRP B may have difficulty aligning its CSI-RS transmission timing and pattern with TRP A, and may be similarly applied or extended to configurations in which two TRPs exchange their CSI-RS transmission timing and pattern with each other.

[0256] In an exemplary embodiment of the communication system, the transmission scheme between TRPs or between a TRP and a terminal may vary depending on whether all TRPs are connected to the same base station or to different base stations. For example, if TRP A and TRP B are connected to the same base station, all TRPs may utilize the RRC transmission scheme. On the other hand, if TRP A and TRP B are connected to different base stations, the terminal may establish an RRC connection with only one base station. For example, assuming that the terminal is in an RRC connection state with a base station connected to TRP A, the terminal may be regarded as being in a multi-connection state with a base station connected to TRP B via signaling radio bearer 3 (SRB3). The base station connected to TRP B and the terminal may exchange information such as SN RRC reconfiguration, SN RRC reconfiguration completion, SN management report, and SN UE assistance information via SRB3.

[0257] According to an exemplary embodiment of a beam management method and apparatus in a communication system, a beam combination for communication between a terminal and multiple TRPs can be determined based on a signaling process between the terminal and the multiple TRPs. Information about candidate beams (or beam candidate groups) for each TRP can be sent and received between the terminal and the multiple TRPs. Thus, one or more beam combinations can be determined. Among the one or more beam combinations thus determined, a beam combination can be selected based on a measurement result at the terminal. In the above manner, a beam adjustment process for communication between a terminal and multiple TRPs can be facilitated.

[0258] However, the effects that can be achieved in the communication system by the exemplary embodiments of the beam management method and apparatus are not limited to those mentioned above. Based on the configuration described in the present invention, it is expected that those skilled in the art in the art to which the present invention belongs can clearly understand other effects that are not mentioned.

[0259] The operation of the method according to the exemplary embodiment of the present invention can be implemented as a computer-readable program or code in a computer-readable recording medium. The computer-readable recording medium may include a recording device of all types having data that can be read by a computer system. In addition, the computer-readable recording medium can store and execute programs or codes, which can be distributed in a computer system connected via a network and read by a computer in a distributed manner.

[0260] Computer readable recording media may include hardware devices specifically configured to store and execute program instructions, such as ROM, RAM or flash memory. Program instructions may include not only machine language codes created by a compiler, but also high-level language codes that can be executed by a computer using an interpreter.

[0261] Although some aspects of the present invention have been described in the context of a device, these aspects may indicate the corresponding description according to the method, and a block or device may correspond to the step of the method or the feature of the step. Similarly, the aspects described in the context of the method may be represented as the feature of a corresponding block or project or a corresponding device. Some or all steps of the method may be performed by (or using) a hardware device such as a microprocessor, a programmable computer or an electronic circuit. In some embodiments, one or more of the most important steps of the method may be performed by such a device.

[0262] In some exemplary embodiments, a programmable logic device such as a field programmable gate array can be used to perform some or all of the functions of the methods described herein. In some exemplary embodiments, the field programmable gate array can be operated with a microprocessor to perform one of the methods described herein. Typically, the method is preferably performed by a specific hardware device.

[0263] The description of the present invention is merely exemplary in nature, and therefore variant forms that do not deviate from the essence of the present invention are intended to be within the scope of the present invention. Such variant forms should not be considered as departing from the spirit and scope of the present invention. Therefore, it will be understood by those of ordinary skill in the art that various changes in form and details may be made without departing from the spirit and scope defined by the appended claims.

Claims

1. A method for operating a first communication node, comprising: receiving, from a first transmit and receive point (TRP) and a second TRP, information of one or more candidate beams for each of the first TRP and the second TRP; Sending information of one or more candidate beams of the second TRP to the first TRP; Sending information of one or more candidate beams of the first TRP to the second TRP; receiving information of one or more beam combinations from a first TRP; sending information about a first measurement value for each beam combination corresponding to each of the one or more beam combinations to a first TRP; as well as receiving, from the first TRP, information of a first beam combination selected based on information regarding a first measurement value for each beam combination, Wherein, each of the one or more beam combinations is configured as a combination of one beam of one or more candidate beams of the first TRP and one beam of one or more candidate beams of the second TRP.

2. The operating method according to claim 1, wherein: The information about the first measurement value for each beam combination is sent including: receiving a first signal transmitted from a first TRP and a second TRP, the first signal corresponding to each of one or more beam combinations; performing a measurement operation on the received first signal; and sending information about a first measurement value for each beam combination obtained based at least on the measurement operation to the first TRP, Among them, when receiving the first signal, the receiving time of the first signal sent from the first TRP and the receiving time of the first signal sent from the second TRP are the same as each other.

3. The operating method according to claim 2, wherein: When receiving the first signal, the first signal sent from the first TRP is received based on a first time period configured according to information of one or more candidate beams of the first TRP, and the second signal sent from the second TRP is received based on a second time period configured according to information of one or more candidate beams of the second TRP.

4. The operating method according to claim 1, wherein: The information about the first measurement value for each beam combination is sent including: receiving information of a first threshold corresponding to the first measurement value from the second TRP; and Information on the first threshold received from the second TRP and information on the first measurement value of each beam combination are sent to the first TRP.

5. The operating method according to claim 1, wherein: The first measurement value is a signal to interference plus noise ratio (SINR) value of the first signal, and transmitting information about the first measurement value for each beam combination includes: receiving, by a first panel in a first communication node corresponding to the first TRP, a first signal transmitted from the first TRP; receiving, by a second panel in the first communication node corresponding to the second TRP, a first signal transmitted from the second TRP; obtaining a first measurement value for each of the received first signals; Mapping the obtained first measurement value to each of the one or more beam combinations to obtain information of the first measurement value of each beam combination; and Information on at least the first measurement value of each beam combination is sent to the first TRP.

6. The operating method according to claim 1, further comprising: receiving, before receiving information of the one or more candidate beams of each of the first TRP and the second TRP, information related to a transmission time of a first signal of the first TRP from the first TRP; as well as Information related to the sending time of the first signal of the first TRP is sent to the second TRP.

7. The operating method according to claim 1, further comprising: Before receiving information about one or more beam combinations, sending information about one or more candidate beams of the first communication node to the first TRP, Among them, the first beam combination selected by the first TRP includes: a first beam among one or more candidate beams of the first TRP, a second beam among one or more candidate beams of the second TRP, and a third beam among one or more candidate beams of the first communication node.

8. The operating method according to claim 1, further comprising: Before receiving information about one or more beam combinations, sending information about one or more candidate beams of the first communication node to the first TRP, Among them, the first beam combination selected by the first TRP includes at least: a first beam among one or more candidate beams of the first TRP, a second beam among one or more candidate beams of the second TRP, and a third beam corresponding to the first TRP and a fourth beam corresponding to the second TRP among one or more candidate beams of the first communication node.

9. The operating method according to claim 1, further comprising: After receiving the information of the first beam combination, the received information of the first beam combination is sent to the second TRP.

10. A method of operating a first transmission and reception point (TRP), comprising: configuring one or more candidate beams of a first TRP; Sending information of one or more candidate beams of a first TRP to a first communication node; receiving information of one or more candidate beams of a second TRP from the first communication node; configuring one or more beam combinations; sending information of one or more beam combinations to a first communication node; receiving, from a first communication node, information regarding one or more first measurements of one or more first signals corresponding to the one or more beam combinations, respectively; selecting a first beam combination from the one or more beam combinations based on information related to the one or more first measurements; as well as sending information of the selected first beam combination to the first communication node, Wherein, each of the one or more beam combinations is configured as a combination of one beam of one or more candidate beams of the first TRP and one beam of one or more candidate beams of the second TRP.

11. The operating method according to claim 10, further comprising: Before sending information about one or more candidate beams, information about the transmission time of one or more first signals of the first TRP is sent to the first communication node.

12. The operating method according to claim 10, further comprising: Before configuring one or more beam combinations, information about the transmission time of one or more first signals sent from the first TRP is sent to the first communication node, and the information about the transmission time is used to adjust the transmission time of one or more first signals sent from the second TRP.

13. The operating method according to claim 10, wherein: The first measurement value is a signal to interference plus noise ratio (SINR) value of the first signal, the information related to the one or more first measurement values ​​includes information of a first threshold corresponding to the one or more first measurement values ​​and information of the first measurement value of each beam combination, and selecting the first beam combination includes: information identifying a second threshold value predetermined by the first TRP corresponding to the one or more first measurements; and A first beam combination is selected from the one or more beam combinations based on information of the first threshold, information of the second threshold, and information of the first measurement value of each beam combination.

14. The operating method according to claim 10, further comprising: Before sending the information of the one or more beam combinations, receiving information of one or more candidate beams of the first communication node from the first communication node, Among them, the first beam combination includes: a first beam among one or more candidate beams of a first TRP, a second beam among one or more candidate beams of a second TRP, and a third beam among one or more candidate beams of a first communication node.

15. The operating method according to claim 10, further comprising: Before sending the information of the one or more beam combinations, receiving information of one or more candidate beams of the first communication node from the first communication node, Among them, the first beam combination includes: a first beam among one or more candidate beams of a first TRP, a second beam among one or more candidate beams of a second TRP, and a third beam corresponding to the first TRP and a fourth beam corresponding to the second TRP among one or more candidate beams of a first communication node.

16. A first communication node comprising at least one processor, wherein the at least one processor causes the first communication node to execute: receiving, from a first transmit and receive point (TRP) and a second TRP, information of one or more candidate beams for each of the first TRP and the second TRP; Sending information of one or more candidate beams of the second TRP to the first TRP; Sending information of one or more candidate beams of the first TRP to the second TRP; receiving information of one or more beam combinations from a first TRP; sending information about a first measurement value for each beam combination corresponding to each of the one or more beam combinations to a first TRP; as well as receiving, from the first TRP, information of a first beam combination selected based on information regarding a first measurement value for each beam combination, Wherein, each of the one or more beam combinations is configured as a combination of one beam of one or more candidate beams of the first TRP and one beam of one or more candidate beams of the second TRP.

17. The first communication node according to claim 16, wherein: When sending information about the first measurement value for each beam combination, the at least one processor causes the first communication node to execute: receiving a first signal transmitted from a first TRP and a second TRP, the first signal corresponding to each of one or more beam combinations; performing a measurement operation on the received first signal; as well as sending information about a first measurement value for each beam combination obtained based at least on the measurement operation to the first TRP, Among them, when receiving the first signal, the receiving time of the first signal sent from the first TRP and the receiving time of the first signal sent from the second TRP are the same as each other.

18. The first communication node according to claim 16, wherein: When sending information about the first measurement value for each beam combination, the at least one processor causes the first communication node to execute: receiving information of a first threshold corresponding to the first measurement value from a second TRP; as well as Information on the first threshold received from the second TRP and information on the first measurement value of each beam combination are sent to the first TRP.

19. The first communication node according to claim 16, wherein: The first measurement value is a signal to interference plus noise ratio (SINR) value of the first signal, and when sending information about the first measurement value for each beam combination, the at least one processor causes the first communication node to perform: receiving, by a first panel in a first communication node corresponding to the first TRP, a first signal transmitted from the first TRP; receiving, by a second panel in the first communication node corresponding to the second TRP, a first signal transmitted from the second TRP; obtaining a first measurement value for each of the received first signals; Mapping the obtained first measurement value to each of the one or more beam combinations to obtain information of the first measurement value of each beam combination; as well as Information on at least the first measurement value of each beam combination is sent to the first TRP.

20. The first communication node according to claim 16, wherein: The at least one processor further causes the first communication node to execute: receiving, before receiving information of the one or more candidate beams of each of the first TRP and the second TRP, information related to a transmission time of a first signal of the first TRP from the first TRP; as well as Information related to the sending time of the first signal of the first TRP is sent to the second TRP.

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