Method and apparatus for beam management in hybrid field comprising near field and far field

Abstract

This method of a user equipment (UE) comprises the steps of: receiving, from a base station, configuration information for a beam management procedure; performing a first measurement operation on a far-field beam of the base station on the basis of the configuration information; determining an optimal far-field beam pair on the basis of the result of the first measurement operation; performing a second measurement operation on one or more near-field beam pairs determined on the basis of the result of the first measurement operation; determining an optimal near-field beam pair on the basis of the result of the second measurement operation; determining a final beam pair from among the optimal far-field beam pair and the optimal near-field beam pair; and communicating with the base station on the basis of the final beam pair.

Description

Method and apparatus for beam management in a hybrid field including a near field and a far field

[0001] The present disclosure relates to an improved communication technology, and more specifically, to a beam management technology in a hybrid field including a near-field and a far-field.

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

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

[0004] Meanwhile, multiple scatterers may exist between the base station and the terminal, and due to these scatterers, multiple paths may exist between the base station and the terminal. Each of the multiple paths may have different electromagnetic characteristics. Some of the multiple paths may have near-field characteristics, while others may have far-field characteristics. A path having near-field characteristics can be defined as a near-field path, and a path having far-field characteristics can be defined as a far-field path. An environment containing near-field paths and far-field paths can be defined as a hybrid field (e.g., a hybrid field environment).

[0005] In order to determine which path—the near-field path or the far-field path—is optimal in a hybrid field environment, communication nodes (e.g., base stations and / or terminals) must perform beam management procedures for both the near-field path and the far-field path. In this case, the complexity of the procedures at the communication node may increase, and finding the optimal path may take a significant amount of time.

[0006] The objective of the present disclosure to solve the above-mentioned problems is to provide a method and apparatus for beam management in a hybrid field including a near-field and a far-field.

[0007] A method of user equipment (UE) according to embodiments of the present disclosure for achieving the above objective comprises: receiving configuration information for a beam management procedure from a base station; performing a first measurement operation for a far-field beam of the base station based on the configuration information; determining an optimal far-field beam pair based on the result of the first measurement operation; performing a second measurement operation for one or more near-field beam pairs determined based on the result of the first measurement operation; determining an optimal near-field beam pair based on the result of the second measurement operation; determining a final beam pair among the optimal far-field beam pair and the optimal near-field beam pair; and communicating with the base station based on the final beam pair.

[0008] The first measurement operation can be performed on a signal transmitted through far-field beam sweeping of the base station, and the second measurement operation can be performed on a signal transmitted through near-field beam sweeping of the base station.

[0009] The optimal far-field beam pair may be a beam pair having an RSRP greater than or equal to the far-field RSRP (reference signal received power) threshold among all beam pairs between the UE and the base station, and the one or more near-field beam pairs may be beam pairs having an RSRP less than the far-field RSRP threshold and greater than or equal to the near-field RSRP threshold among all beam pairs, and the optimal near-field beam pair may be a beam pair having the largest RSRP among the one or more near-field beam pairs.

[0010] The above method of the UE may further include the step of transmitting a UE capability response to the base station, the response including a capability to report the result of the first measurement operation, and the method of reporting the result of the first measurement operation may be determined based on the capability to report.

[0011] The above method of the UE may further include the step of receiving a UE capability request from the base station, and the UE capability response may be transmitted as a response to the UE capability request.

[0012] The method of the above UE may further include the step of transmitting the result of the first measurement operation to the base station, and the one or more near-field beam pairs may be determined at the base station based on the result of the first measurement operation.

[0013] The step of performing the second measurement operation may include: determining one or more near-field beam pairs by applying a beam pair determination criterion received from the base station to the result of the first measurement operation; and performing the second measurement operation for the one or more near-field beam pairs.

[0014] The above configuration information may include beam management information, and a type field included in the beam management information may indicate the type of beam management procedure performed between the UE and the base station, and the type of beam management procedure may be classified into a far-field beam management procedure, a near-field beam management procedure, and a hybrid-field beam management procedure, and the hybrid-field beam management procedure may include the far-field beam management procedure and the near-field beam management procedure.

[0015] The above configuration information may include reporting information, and the reporting information may include at least one of information indicating a reporting method, information indicating a reporting target, or an RSRP threshold, and the reporting method may be classified as an individual reporting method or a map reporting method, and the reporting target may be one or more beams.

[0016] The above setting information may include reporting format information of an RSRP map including the result of the first measurement operation, and the reporting format information may include at least one of a base station-UE beam index, a performance metric, splitting information, or a reporting type, and the splitting information may indicate whether to split the RSRP map transmission, and the reporting type may indicate periodic reporting or event-triggered reporting of the RSRP map.

[0017] The above setting information may include beam pair determination criteria, and the beam pair determination criteria may include at least one of a far-field RSRP threshold, a near-field RSRP threshold, a maximum number of determinable beam pairs, or a timer indicating the time for which the beam pair determination procedure is performed.

[0018] A method of a base station according to embodiments of the present disclosure for achieving the above objective comprises: transmitting configuration information for a beam management procedure to a UE (user equipment); transmitting a signal to the UE by performing far-field beam sweeping; determining an optimal far-field beam pair based on a first measurement result for the signal transmitted through the far-field beam sweeping; transmitting a signal to the UE by performing near-field beam sweeping for measuring one or more near-field beam pairs determined based on the first measurement result; determining an optimal near-field beam pair based on a second measurement result for the signal transmitted through the near-field beam sweeping; determining a final beam pair among the optimal far-field beam pair and the optimal near-field beam pair; and communicating with the UE based on the final beam pair.

[0019] The optimal far-field beam pair may be a beam pair having an RSRP greater than or equal to the far-field RSRP (reference signal received power) threshold among all beam pairs between the UE and the base station, and the one or more near-field beam pairs may be beam pairs having an RSRP less than the far-field RSRP threshold and greater than or equal to the near-field RSRP threshold among all beam pairs, and the optimal near-field beam pair may be a beam pair having the largest RSRP among the one or more near-field beam pairs.

[0020] The method of the base station may further include the step of receiving a UE capability response from the UE, which includes a reporting capability for the first measurement result, and the reporting method for the first measurement result may be determined based on the reporting capability.

[0021] The method of the base station may further include the step of receiving the first measurement result from the UE; and the step of determining the one or more near-field beam pairs based on the first measurement result.

[0022] The method of the base station may further include the step of receiving information of one or more near-field beam pairs determined by the UE based on the first measurement result from the UE.

[0023] The above configuration information may include beam management information, and a type field included in the beam management information may indicate the type of beam management procedure performed between the UE and the base station, and the type of beam management procedure may be classified into a far-field beam management procedure, a near-field beam management procedure, and a hybrid-field beam management procedure, and the hybrid-field beam management procedure may include the far-field beam management procedure and the near-field beam management procedure.

[0024] The above configuration information may include reporting information, and the reporting information may include at least one of information indicating a reporting method, information indicating a reporting target, or an RSRP threshold, and the reporting method may be classified as an individual reporting method or a map reporting method, and the reporting target may be one or more beams.

[0025] The above setting information may include reporting format information of an RSRP map including the first measurement result, and the reporting format information may include at least one of a base station-UE beam index, a performance metric, splitting information, or a reporting type, and the splitting information may indicate whether to split transmission of the RSRP map, and the reporting type may indicate periodic reporting or event-triggered reporting of the RSRP map.

[0026] The above setting information may include beam pair determination criteria, and the beam pair determination criteria may include at least one of a far-field RSRP threshold, a near-field RSRP threshold, a maximum number of determinable beam pairs, or a timer indicating the time for which the beam pair determination procedure is performed.

[0027] According to the present disclosure, a beam management procedure for a hybrid field including a near-field and a far-field allows for the determination of an optimal beam for a near-field path having near-field characteristics and a far-field path having far-field characteristics, the complexity of the procedure for determining the optimal beam can be reduced, and the time required to determine the optimal beam can be reduced. Based on the requirements of a network operator, an optimal beam considering near-field and far-field characteristics in a communication system can be determined based on various methods. By utilizing an optimal beam considering near-field and far-field characteristics in a communication system (e.g., a next-generation communication system), stable and excellent beamforming performance can be achieved.

[0028] FIG. 1 is a conceptual diagram illustrating embodiments of a communication system.

[0029] FIG. 2 is a block diagram illustrating embodiments of communication nodes constituting a communication system.

[0030] FIG. 3 is a block diagram illustrating embodiments of communication nodes performing communication.

[0031] FIG. 4a is a block diagram illustrating embodiments of a transmission path.

[0032] FIG. 4b is a block diagram illustrating embodiments of a receiving path.

[0033] FIG. 5 is a conceptual diagram illustrating embodiments of a system frame in a communication system.

[0034] FIG. 6 is a conceptual diagram illustrating embodiments of subframes in a communication system.

[0035] FIG. 7 is a conceptual diagram illustrating embodiments of slots in a communication system.

[0036] FIG. 8 is a conceptual diagram illustrating embodiments of time-frequency resources in a communication system.

[0037] Figure 9 is a conceptual diagram illustrating a multipath channel model in a hybrid field environment.

[0038] Figure 10 is a conceptual diagram illustrating the beam gain according to the electromagnetic wave region where the terminal is located when beam sweeping is performed using a far-field beam.

[0039] Figure 11 is a conceptual diagram illustrating joint far-field beam sweeping between a base station and a terminal.

[0040] Figure 12 is a conceptual diagram illustrating an RSRP map.

[0041] Figure 13 is a conceptual diagram illustrating angle and distance domain beam sweeping for a near-field path to find the optimal BS beam.

[0042] FIG. 14 is a conceptual diagram illustrating angle and distance domain beam sweeping for a near-field path to find the optimal UE beam.

[0043] Figure 15 is a flowchart illustrating the beam sweeping procedure in a hybrid field environment.

[0044] The present disclosure is capable of various modifications and may have various embodiments, and specific embodiments are illustrated in the drawings and described in detail. However, this is not intended to limit the present disclosure to specific embodiments and should be understood to include all modifications, equivalents, and substitutions that fall within the spirit and scope of the present disclosure.

[0045] Terms such as "first," "second," etc., may be used to describe various components, but said components should not be limited by said terms. Such terms are used solely for the purpose of distinguishing one component from another. For example, without departing from the scope of the present disclosure, the first component may be named the second component, and similarly, the second component may be named the first component. The term "and / or" may mean a combination of a plurality of related described items or any of a plurality of related described items.

[0046] In the present disclosure, "at least one of A and B" may mean "at least one of A or B" or "at least one of one or more combinations of A and B". Additionally, in the present disclosure, "at least one of A and B" may mean "at least one of A or B" or "at least one of one or more combinations of A and B".

[0047] In the present disclosure, (re)transmission may mean "transmission," "retransmission," or "transmission and retransmission"; (re)setting may mean "setting," "resetting," or "setting and resetting"; (re)connection may mean "connection," "reconnection," or "connection and reconnection"; and (re)connection may mean "connection," "reconnection," or "connection and reconnection".

[0048] When it is stated that one component is "connected" or "connected" to another component, it should be understood that while it may be directly connected or connected to that other component, there may also be other components in between. On the other hand, when it is stated that one component is "directly connected" or "directly connected" to another component, it should be understood that there are no other components in between.

[0049] The terms used in this disclosure are used merely to describe specific embodiments and are not intended to limit this disclosure. The singular expression includes the plural expression unless the context clearly indicates otherwise. In this disclosure, terms such as “comprising” or “having” are intended to specify the existence of the features, numbers, steps, actions, components, parts, or combinations thereof described in the specification, and should be understood as not precluding the existence or addition of one or more other features, numbers, steps, actions, components, parts, or combinations thereof.

[0050] Unless otherwise defined, all terms used herein, including technical or scientific terms, have the same meaning as generally understood by those skilled in the art to which this disclosure pertains. Terms such as those defined in commonly used dictionaries should be interpreted as having a meaning consistent with their meaning in the context of the relevant technology, and should not be interpreted in an ideal or overly formal sense unless explicitly defined in this disclosure.

[0051] Hereinafter, preferred embodiments of the present disclosure will be described in more detail with reference to the attached drawings. To facilitate overall understanding in describing the present disclosure, the same reference numerals are used for identical components in the drawings, and redundant descriptions of identical components are omitted. Operations according to combinations of embodiments, extensions of embodiments, and / or modifications of embodiments may be performed, as well as the embodiments explicitly described in the present disclosure. The performance of some operations may be omitted, and the order of operations may be changed.

[0052] In the embodiments, even when a method performed at a first communication node among the communication nodes (e.g., transmission or reception of a signal) is described, the corresponding second communication node may perform a method corresponding to the method performed at the first communication node (e.g., reception or transmission of a signal). That is, when the operation of a UE (user equipment) is described, the corresponding base station may perform an operation corresponding to the operation of the UE. Conversely, when the operation of a base station is described, the corresponding UE may perform an operation corresponding to the operation of the base station.

[0053] A base station may be referred to as Node B, evolved Node B, gNode B (next generation node B), gNB, device, apparatus, node, communication node, BTS (base transceiver station), RRH (radio remote head), TRP (transmission reception point), RU (radio unit), RSU (road side unit), radio transceiver, access point, access node, etc. A UE may be referred to as terminal, device, apparatus, node, communication node, end node, access terminal, mobile terminal, station, subscriber station, mobile station, portable subscriber station, OBU (on-board unit), etc.

[0054] In the present disclosure, signaling may be at least one of upper-layer signaling, MAC signaling, or PHY (physical) signaling. A message used for upper-layer signaling may be referred to as an "upper-layer message" or an "upper-layer signaling message." A message used for MAC signaling may be referred to as a "MAC message" or a "MAC signaling message." A message used for PHY signaling may be referred to as a "PHY message" or a "PHY signaling message." Upper-layer signaling may refer to the transmission and reception operations of system information (e.g., MIB (master information block), SIB (system information block)) and / or RRC (radio resource control) messages. MAC signaling may refer to the transmission and reception operations of MAC CE (control element). PHY signaling may refer to the transmission and reception operations of control information (e.g., DCI (downlink control information), UCI (uplink control information), SCI (sidelink control information)).

[0055] In the present disclosure, "setting an operation (e.g., a transmission operation)" may mean that "setting information for said operation (e.g., an information element, a parameter)" and / or "information directing the performance of said operation" is signaled. "Setting an information element (e.g., a parameter)" may mean that said information element is signaled. In the present disclosure, "signal and / or channel" may mean a signal, a channel, or "signal and channel," and "signal" may be used to mean "signal and / or channel." In the present disclosure, "time" and "time point" may be used interchangeably. "Time" may be interpreted as a time or a time point depending on the context, and "time point" may be interpreted as a time point or a time depending on the context.

[0056] In the present disclosure, a phrase containing "~ case (e.g., when ~)" may be expressed as a phrase containing "~ based on (e.g., based on ~)" or a phrase containing "~ in response to (e.g., in response to ~)". In other words, a phrase containing "~ case" may be interpreted as identical or similar to a phrase containing "~ based on" or a phrase containing "~ in response to".

[0057] The communication networks to which the embodiments are applied are not limited to those described below, and the embodiments may be applied to various communication networks (e.g., 4G communication networks, 5G communication networks, and / or 6G communication networks). Here, the term "communication network" may be used interchangeably with "communication system."

[0058] FIG. 1 is a conceptual diagram illustrating embodiments of a communication system.

[0059] Referring to FIG. 1, the communication system (100) may include a plurality of communication nodes (110-1, 110-2, 110-3, 120-1, 120-2, 130-1, 130-2, 130-3, 130-4, 130-5, 130-6). Additionally, the communication system (100) may further include a core network (e.g., an S-GW (serving-gateway), a P-GW (PDN (packet data network)-gateway), and an MME (mobility management entity)). If the communication system (100) is a 5G communication system (e.g., a new radio (NR) system), the core network may include an AMF (access and mobility management function), a UPF (user plane function), an SMF (session management function), etc.

[0060] Multiple communication nodes (110 to 130) can support communication protocols defined in 3GPP (3rd generation partnership project) standards (e.g., LTE communication protocol, LTE-A communication protocol, NR communication protocol, etc.). Multiple communication nodes (110 to 130) can support CDMA (code division multiple access) technology, WCDMA (wideband CDMA) technology, TDMA (time division multiple access) technology, FDMA (frequency division multiple access) technology, OFDM (orthogonal frequency division multiplexing) technology, Filtered OFDM technology, CP (cyclic prefix)-OFDM technology, DFT-s-OFDM (discrete Fourier transform-spread-OFDM) technology, OFDMA (orthogonal frequency division multiple access) technology, SC (single carrier)-FDMA technology, NOMA (non-orthogonal multiple access) technology, GFDM (generalized frequency division multiplexing) technology, FBMC (filter bank multi-carrier) technology, UFMC (universal filtered multi-carrier) technology, SDMA (space division multiple access) technology, etc. Each of the multiple communication nodes may have the following structure.

[0061] FIG. 2 is a block diagram illustrating embodiments of communication nodes constituting a communication system.

[0062] Referring to FIG. 2, the communication node (200) may include at least one processor (210), a memory (220), and a transceiver (230) that is connected to a network to perform communication. Additionally, the communication node (200) may further include an input interface device (240), an output interface device (250), a storage device (260), etc. Each component included in the communication node (200) may be connected by a bus (270) to communicate with one another.

[0063] The processor (210) can execute a program command stored in at least one of the memory (220) and the storage device (260). The processor (210) may mean a central processing unit (CPU), a graphics processing unit (GPU), or a dedicated processor on which the methods according to embodiments of the present disclosure are performed. 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 be composed of at least one of read-only memory (ROM) and random access memory (RAM).

[0064] Referring again to FIG. 1, the communication system (100) may include a plurality of base stations (110-1, 110-2, 110-3, 120-1, 120-2) and a plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6). Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) may form a macro cell. Each of the fourth base station (120-1) and the fifth base station (120-2) may form a small cell. The fourth base station (120-1), the third terminal (130-3), and the fourth terminal (130-4) may be located within the cell coverage of the first base station (110-1). The second terminal (130-2), the fourth terminal (130-4), and the fifth terminal (130-5) may be located within the cell coverage of the second base station (110-2). The fifth base station (120-2), the fourth terminal (130-4), the fifth terminal (130-5), and the sixth terminal (130-6) may be located within the cell coverage of the third base station (110-3). The first terminal (130-1) may be located within the cell coverage of the fourth base station (120-1). The sixth terminal (130-6) may be located within 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, 120-2) may be referred to as NB (NodeB), eNB (evolved NodeB), gNB, ABS (advanced base station), HR-BS (high reliability-base station), BTS (base transceiver station), radio base station, radio transceiver, access point, access node, RAS (radio access station), MMR-BS (mobile multihop relay-base station), RS (relay station), ARS (advanced relay station), HR-RS (high reliability-relay station), HNB (home NodeB), HeNB (home eNodeB), RSU (road side unit), RRH (radio remote head), TP (transmission point), TRP (transmission and reception point), etc.

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

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

[0068] In addition, each of the multiple base stations (110-1, 110-2, 110-3, 120-1, 120-2) can support MIMO transmission (e.g., SU (single user)-MIMO, MU (multi user)-MIMO, massive MIMO, etc.), CoMP (coordinated multipoint) transmission, carrier aggregation (CA) transmission, transmission in an unlicensed band, sidelink communication (e.g., D2D (device to device communication), ProSe (proximity services)), IoT (Internet of Things) communication, dual connectivity (DC), etc. Here, each of the plurality of terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) can perform an operation corresponding to the base station (110-1, 110-2, 110-3, 120-1, 120-2) and an operation supported by the base station (110-1, 110-2, 110-3, 120-1, 120-2). For example, the second base station (110-2) can transmit a signal to the fourth terminal (130-4) based on the SU-MIMO method, and the fourth terminal (130-4) can receive a signal from the second base station (110-2) based on the SU-MIMO method. Alternatively, the second base station (110-2) can transmit a signal to the fourth terminal (130-4) and the fifth terminal (130-5) based on the MU-MIMO method, and each of the fourth terminal (130-4) and the fifth terminal (130-5) can receive a signal from the second base station (110-2) by the MU-MIMO method.

[0069] Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) can transmit a signal to the fourth terminal (130-4) based on the CoMP method, 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) by the CoMP method. Each of the multiple base stations (110-1, 110-2, 110-3, 120-1, 120-2) can transmit and receive signals based on the CA method with terminals (130-1, 130-2, 130-3, 130-4, 130-5, 130-6) within its cell coverage area. Each of the first base station (110-1), the second base station (110-2), and the third base station (110-3) can control sidelink communication between the fourth terminal (130-4) and the fifth terminal (130-5), and each of the fourth terminal (130-4) and the fifth terminal (130-5) can perform sidelink communication by controlling each of the second base station (110-2) and the third base station (110-3).

[0070] Meanwhile, communication nodes performing communication in a communication network may be configured as follows. The communication node shown in FIG. 3 may be a specific embodiment of the communication node shown in FIG. 2.

[0071] FIG. 3 is a block diagram illustrating embodiments of communication nodes performing communication.

[0072] Referring to FIG. 3, the first communication node (300a) and the second communication node (300b) may each be a base station or a UE. The first communication node (300a) may transmit a signal to the second communication node (300b). A transmission processor (311) included in the first communication node (300a) may receive data (e.g., a data unit) from a data source (310). The transmission processor (311) may receive control information from a controller (316). The control information may include at least one of system information, RRC setting information (e.g., information set by RRC signaling), MAC control information (e.g., MAC CE), or PHY control information (e.g., DCI, SCI).

[0073] The transmitting processor (311) can generate data symbol(s) by performing processing operations on data (e.g., encoding operations, symbol mapping operations, etc.). The transmitting processor (311) can generate control symbol(s) by performing processing operations on control information (e.g., encoding operations, symbol mapping operations, etc.). Additionally, the transmitting processor (311) can generate synchronization / reference symbol(s) for synchronization signals and / or reference signals.

[0074] The Tx MIMO processor (312) can perform spatial processing operations (e.g., precoding operations) on data symbol(s), control symbol(s), and / or synchronization / reference symbol(s). The output of the Tx MIMO processor (312) (e.g., a symbol stream) can be provided to modulators (MODs) included in transceivers (313a to 313t). The modulators (MODs) can perform processing operations on the symbol stream to generate modulated symbols and perform additional processing operations on the modulated symbols (e.g., analog conversion operations, amplification operations, filtering operations, up-conversion operations) to generate signals. The signals generated by the modulators (MODs) of the transceivers (313a to 313t) can be transmitted through antennas (314a to 314t).

[0075] Signals transmitted by the first communication node (300a) can be received at the antennas (364a to 364r) of the second communication node (300b). Signals received at the antennas (364a to 364r) can be provided to demodulators (DEMODs) included in the transceivers (363a to 363r). The demodulators (DEMODs) can obtain samples by performing processing operations on the signals (e.g., filtering, amplification, down-conversion, digital conversion). The demodulators (DEMODs) can obtain symbols by performing additional processing operations on the samples. The MIMO detector (362) can perform MIMO detection operations on the symbols. The receiving processor (361) can perform processing operations on the symbols (e.g., deinterleaving, decoding). The output of the receiving processor (361) can be provided to the data sink (360) and the controller (366). For example, data can be provided to the data sink (360), and control information can be provided to the controller (366).

[0076] Meanwhile, the second communication node (300b) can transmit a signal to the first communication node (300a). The transmission processor (368) included in the second communication node (300b) can receive data (e.g., a data unit) from the data source (367) and can generate data symbol(s) by performing a processing operation on the data. The transmission processor (368) can receive control information from the controller (366) and can generate control symbol(s) by performing a processing operation on the control information. Additionally, the transmission processor (368) can generate reference symbol(s) by performing a processing operation on a reference signal.

[0077] The Tx MIMO processor (369) can perform spatial processing operations (e.g., precoding operations) on data symbol(s), control symbol(s), and / or reference symbol(s). The output of the Tx MIMO processor (369) (e.g., a symbol stream) can be provided to modulators (MODs) included in transceivers (363a to 363t). The modulators (MODs) can perform processing operations on the symbol stream to generate modulated symbols and perform additional processing operations on the modulated symbols (e.g., analog conversion operations, amplification operations, filtering operations, up-conversion operations) to generate signals. The signals generated by the modulators (MODs) of the transceivers (363a to 363t) can be transmitted through antennas (364a to 364t).

[0078] Signals transmitted by the second communication node (300b) can be received at the antennas (314a to 314r) of the first communication node (300a). Signals received at the antennas (314a to 314r) can be provided to demodulators (DEMODs) included in the transceivers (313a to 313r). The demodulators (DEMODs) can obtain samples by performing processing operations on the signals (e.g., filtering operation, amplification operation, down-conversion operation, digital conversion operation). The demodulators (DEMODs) can obtain symbols by performing additional processing operations on the samples. The MIMO detector (320) can perform MIMO detection operations on the symbols. The receiving processor (319) can perform processing operations on the symbols (e.g., deinterleaving operation, decoding operation). The output of the receiving processor (319) can be provided to the data sink (318) and the controller (316). For example, data can be provided to the data sink (318), and control information can be provided to the controller (316).

[0079] The memories (315 and 365) may store data, control information, and / or program code. The scheduler (317) may perform scheduling operations for communication. The processors (311, 312, 319, 361, 368, 369) and controllers (316, 366) shown in FIG. 3 may be the processor (210) shown in FIG. 2 and may be used to perform the methods described in this disclosure.

[0080] FIG. 4a is a block diagram illustrating embodiments of a transmission path, and FIG. 4b is a block diagram illustrating embodiments of a reception path.

[0081] Referring to FIGS. 4a and 4b, a transmission path (410) may be implemented at a communication node that transmits a signal, and a reception path (420) may be implemented at a communication node that receives a signal. The transmission path (410) may include a channel coding and modulation block (411), an S-to-P (serial-to-parallel) block (512), an N IFFT (Inverse Fast Fourier Transform) block (413), a P-to-S (parallel-to-serial) block (414), a CP (cyclic prefix) addition block (415), and an UC (up-converter) (UC) (416). The reception path (420) may include a DC (down-converter) (421), a CP removal block (422), an S-to-P block (423), an N FFT block (424), a P-to-S block (425), and a channel decoding and demodulation block (426). Here, N can be a natural number.

[0082] Information bits in the transmission path (410) can be input to the channel coding and modulation block (411). The channel coding and modulation block (411) can perform coding operations (e.g., LDPC (low-density parity check) (LDPC) coding operations, polar coding operations, etc.) and modulation operations (e.g., QPSK (Quadrature Phase Shift Keying), QAM (Quadrature Amplitude Modulation), etc.) on the information bits. The output of the channel coding and modulation block (411) may be a sequence of modulation symbols.

[0083] The S-to-P block (412) can convert modulated symbols in the frequency domain into parallel symbol streams to generate N parallel symbol streams. N can be the IFFT size or the FFT size. The N IFFT block (413) can generate signals in the time domain by performing an IFFT operation on the N parallel symbol streams. The P-to-S block (414) can convert the output of the N IFFT block (413) (e.g., parallel signals) into a serial signal to generate a serial signal.

[0084] The CP addition block (415) can insert CP into the signal. The UC (416) can up-convert the frequency of the output of the CP addition block (415) to an RF (radio frequency) frequency. Additionally, the output of the CP addition block (415) can be filtered in the baseband before up-conversion.

[0085] A signal transmitted from the transmission path (410) can be input to the reception path (420). The operation in the reception path (420) may be the inverse operation of the operation in the transmission path (410). The DC (421) may down-convert the frequency of the received signal to a baseband frequency. The CP removal block (422) may remove CP from the signal. The output of the CP removal block (422) may be a serial signal. The S-to-P block (423) may convert the serial signal into parallel signals. The N FFT block (424) may generate N parallel signals by performing an FFT algorithm. The P-to-S block (425) may convert the parallel signals into a sequence of modulation symbols. The channel decoding and demodulation block (426) may perform a demodulation operation on the modulation symbols and perform a decoding operation on the result of the demodulation operation to restore the data.

[0086] In FIGS. 4a and 4b, Discrete Fourier Transform (DFT) and Inverse DFT (IDFT) may be used instead of FFT and IFFT. In FIGS. 4a and 4b, each of the blocks (e.g., components) may be implemented by at least one of hardware, software, or firmware. For example, in FIGS. 4a and 4b, some blocks may be implemented by software, and the remaining blocks may be implemented by hardware or a "combination of hardware and software." In FIGS. 4a and 4b, one block may be subdivided into multiple blocks, multiple blocks may be integrated into one block, some blocks may be omitted, and blocks supporting other functions may be added.

[0087] FIG. 5 is a conceptual diagram illustrating embodiments of a system frame in a communication system.

[0088] Referring to FIG. 5, time resources in a communication system can be divided into frames. For example, system frames can be set consecutively in the time domain of the communication system. The length of a system frame can be 10 ms (millisecond). The system frame number (SFN) can be set from #0 to #1023. In this case, 1024 system frames can be repeated in the time domain of the communication system. For example, the SFN of a system frame after system frame #1023 can be #0.

[0089] A single system frame may contain two half frames. The length of a single half frame may be 5ms. A half frame located at the beginning of the system frame may be referred to as "Half Frame #0", and a half frame located at the end of the system frame may be referred to as "Half Frame #1". A system frame may contain 10 subframes. The length of a single subframe may be 1ms. Within a single system frame, the 10 subframes may be referred to as "Subframe #0-9".

[0090] FIG. 6 is a conceptual diagram illustrating embodiments of subframes in a communication system.

[0091] Referring to FIG. 6, one subframe may include n slots, where n is a natural number. Thus, one subframe may consist of one or more slots.

[0092] FIG. 7 is a conceptual diagram illustrating embodiments of slots in a communication system.

[0093] Referring to FIG. 7, a slot may contain one or more symbols. A slot illustrated in FIG. 7 may contain 14 symbols. The length of the slot may vary depending on the number of symbols included in the slot and the length of the symbols. Alternatively, the length of the slot may vary depending on the numerology.

[0094] Numerals applied to physical signals and channels in a communication system may be variable. Numerals may be variable to meet various technical requirements of the communication system. In a communication system where CP (cyclic prefix) based OFDM waveform technology is applied, numerals may include subcarrier spacing and CP length (or CP type). Table 1 may be a first embodiment of a method for configuring numerals for a CP-OFDM based communication system. Depending on the frequency band in which the communication system operates, at least some of the numerals in Table 1 may be supported. Additionally, numerals not listed in Table 1 may be further supported in the communication system.

[0095]

[0096] When the subcarrier spacing is 15 kHz (e.g., μ=0), the slot length may be 1 ms. In this case, one system frame may contain 10 slots. When the subcarrier spacing is 30 kHz (e.g., μ=1), the slot length may be 0.5 ms. In this case, one system frame may contain 20 slots.

[0097] When the subcarrier spacing is 60 kHz (e.g., μ=2), the slot length may be 0.25 ms. In this case, one system frame may contain 40 slots. When the subcarrier spacing is 120 kHz (e.g., μ=3), the slot length may be 0.125 ms. In this case, one system frame may contain 80 slots. When the subcarrier spacing is 240 kHz (e.g., μ=4), the slot length may be 0.0625 ms. In this case, one system frame may contain 160 slots.

[0098] A symbol can be set as a downlink (DL) symbol, a flexible (FL) symbol, or an uplink (UL) symbol. A slot consisting only of a DL symbol may be referred to as a "DL slot," a slot consisting only of an FL symbol may be referred to as a "FL slot," and a slot consisting only of a UL symbol may be referred to as a "UL slot."

[0099] The slot format can be semi-fixed by upper-layer signaling (e.g., RRC signaling). Information indicating the semi-fixed slot format may be included in system information, and the semi-fixed slot format can be set cell-specifically. Additionally, the semi-fixed slot format can be additionally set per terminal through terminal-specific upper-layer signaling (e.g., RRC signaling). The flexible symbols of the cell-specific slot format can be overridden as downlink symbols or uplink symbols by the terminal-specific upper-layer signaling. Furthermore, the slot format can be dynamically indicated by physical layer signaling (e.g., the SFI (slot format indicator) included in the DCI). The semi-fixed slot format can be overridden by the dynamically indicated slot format. For example, the semi-fixed flexible symbols can be overridden as downlink symbols or uplink symbols by the SFI.

[0100] The reference signal may be a CSI-RS (channel state information-reference signal), SRS (sounding reference signal), DM-RS (demodulation-reference signal), PT-RS (phase tracking-reference signal), etc. The channel may be a PBCH (physical broadcast channel), PDCCH (physical downlink control channel), PDSCH (physical downlink shared channel), PUCCH (physical uplink control channel), PUSCH (physical uplink shared channel), PSCCH (physical sidelink control channel), PSSCH (physical sidelink shared channel), etc. In the present disclosure, the control channel may mean PDCCH, PUCCH, or PSCCH, and the data channel may mean PDSCH, PUSCH, or PSSCH.

[0101] FIG. 8 is a conceptual diagram illustrating embodiments of time-frequency resources in a communication system.

[0102] Referring to FIG. 8, a resource consisting of one symbol (e.g., an OFDM symbol) in the time domain and one subcarrier in the frequency domain can be defined as a "RE (resource element)." A resource consisting of one OFDM symbol in the time domain and K subcarriers in the frequency domain can be defined as a "REG (resource element group)." A REG can include K REs. A REG can be used as the basic unit of resource allocation in the frequency domain. K can be a natural number. For example, K can be 12. N can be a natural number. In the slot illustrated in FIG. 7, N can be 14. N OFDM symbols can be used as the basic unit of resource allocation in the time domain.

[0103] In the present disclosure, RB may mean a common RB (CRB). Alternatively, RB may mean a PRB or a virtual RB (VRB). In a communication system, a CRB may mean an RB that constitutes a set of consecutive RBs (e.g., a common RB grid) based on a reference frequency (e.g., point A). A carrier and / or bandwidth portion may be placed on the common RB grid. That is, the carrier and / or bandwidth portion may be composed of CRB(s). An RB or CRB constituting the bandwidth portion may be referred to as a PRB, and within the bandwidth portion, a CRB index may be appropriately converted to a PRB index.

[0104] Downlink data may be transmitted via PDSCH. A base station may transmit configuration information of the PDSCH (e.g., scheduling information) to a terminal via PDCCH. A terminal may obtain the configuration information of the PDSCH by receiving the PDCCH (e.g., downlink control information (DCI)). For example, the configuration information of the PDSCH may include a modulation coding scheme (MCS) used for transmitting and receiving the PDSCH, time resource information of the PDSCH, frequency resource information of the PDSCH, feedback resource information for the PDSCH, etc. PDSCH may refer to a radio resource where downlink data is transmitted and received. Alternatively, PDSCH may refer to the downlink data itself. PDCCH may refer to a radio resource where downlink control information (e.g., DCI) is transmitted and received. Alternatively, PDCCH may refer to the downlink control information itself.

[0105] The terminal may perform a monitoring operation for the PDCCH to receive the PDSCH transmitted from the base station. The base station may notify the terminal of configuration information for the monitoring operation of the PDCCH using a higher-layer message (e.g., a radio resource control (RRC) message). The configuration information for the monitoring operation of the PDCCH may include CORESET (control resource set) information and search space information.

[0106] CORESET information may include PDCCH DMRS (demodulation reference signal) information, PDCCH precoding information, PDCCH occasion information, etc. The PDCCH DMRS may be a DMRS used to demodulate the PDCCH. A PDCCH occasion may be an area where the PDCCH can exist. That is, a PDCCH occasion may be an area where DCI can be transmitted. A PDCCH occasion may be referred to as a PDCCH candidate. PDCCH occasion information may include time resource information and frequency resource information of the PDCCH occasion. In the time domain, the length of the PDCCH occasion may be indicated in symbol units. In the frequency domain, the size of the PDCCH occasion may be indicated in RB units (e.g., PRB (physical resource block) units or CRB (common resource block) units).

[0107] The search space information may include a CORESET ID (identifier) ​​associated with the search space, the period of PDCCH monitoring, and / or an offset. The period and offset of PDCCH monitoring may each be specified in slot units. Additionally, the search space information may further include the index of the symbol where the PDCCH monitoring operation begins.

[0108] A base station may configure a Bandwidth Part (BWP) for downlink communication. BWPs may be configured differently for each terminal. The base station may notify the terminal of the BWP configuration information using upper-layer signaling. Upper-layer signaling may refer to "transmission operations of system information" and / or "transmission operations of Radio Resource Control (RRC) messages." One or more BWPs may be configured for a single terminal. The terminal may receive BWP configuration information from the base station and identify the BWP(s) configured by the base station based on the BWP configuration information. If multiple BWPs are configured for downlink communication, the base station may activate one or more of the multiple BWPs. The base station may transmit the configuration information of the activated BWP(s) to the terminal using at least one of upper-layer signaling, a Medium Access Control (MAC) Control Element (CE), or a DCI. The base station may perform downlink communication using the activated BWP(s). The terminal can identify the activated BWP(s) by receiving configuration information of the activated BWP(s) from the base station, and can perform a downlink reception operation on the activated BWP(s).

[0109] In existing communication systems (e.g., 5G communication systems), beam management procedures are based on the premise that the electromagnetic field between a base station and a terminal is defined as a far-field, and accordingly, the beams used by the base station and the terminal can also be designed based on far-field beams. In future next-generation communication systems (e.g., 6G communication systems), higher frequency bands than those in existing communication systems may be used, and base stations and terminals may have many antennas. When the distance between the base station and the terminal is short, the electromagnetic field between the base station and the terminal can be defined as a near-field.

[0110] Multiple scatterers may exist between a base station and a terminal, and due to these scatterers, communication may be performed through multiple paths. In this case (e.g., in a multipath environment), the electromagnetic field between the base station and the terminal is not determined solely by the distance between the transmitting and receiving antennas of the base station and the terminal, but may be defined differently for each path (e.g., each propagation path) that transmits a valid signal, depending on the location of the scatterers forming that path. For example, even when the distance between the base station and the terminal is shorter than the Rayleigh distance and is defined as a near-field, there may still be signals reaching the terminal that are reflected by scatterers located in the far-field region. For signals transmitted through such paths, it may be more effective to use a far-field beam for transmission rather than a near-field beam.

[0111] An environment in which not only a Line-of-Sight (LoS) path exists between a base station and a terminal, but also multiple paths formed by multiple scatterers exist, and each path can be defined as a different electromagnetic field, can be defined as a hybrid field (e.g., a hybrid field environment). In a hybrid field environment, near-field paths and far-field paths may coexist, and a communication node (e.g., a base station and / or a terminal) can perform efficient communication by appropriately utilizing both near-field beams and far-field beams. A near-field path may refer to a path having near-field characteristics, and a near-field beam may be used for communication in a near-field path. A far-field path may refer to a path having far-field characteristics, and a far-field beam may be used for communication in a far-field path. In this disclosure, a communication node may be interpreted as a base station, a terminal, or 'base station and terminal' depending on the context.

[0112] Figure 9 is a conceptual diagram illustrating a multipath channel model in a hybrid field environment.

[0113] Referring to Fig. 9, in a hybrid field environment, based on the Rayleigh distance, a path passing through a scatterer located within the Rayleigh distance from the transmitter can be defined as a near-field path. A path passing through a scatterer located outside the Rayleigh distance from the transmitter can be defined as a far-field path. It may be important to identify the path that provides the best communication performance among the near-field path and the far-field path. The communication node cannot know in advance which path, the far-field path or the near-field path, is the optimal path.

[0114] A communication node can determine the optimal path for each electromagnetic wave region by performing both a far-field beam management procedure to search for the optimal far-field path and a near-field beam management procedure to search for the optimal near-field path. In this method, since the communication node must transmit beams for each of all possible combinations of angles and distances in the far-field and near-field environments, the computational complexity can be high and a lot of resources can be consumed.

[0115] A low-complexity beam management procedure considering a hybrid field environment is necessary. According to the method proposed in this disclosure, the far-field beam management procedure and the near-field beam management procedure may not be performed independently of each other, and the search dimension in the near-field beam management procedure may be reduced based on the result of the far-field beam management procedure.

[0116] - Hybrid intestinal environment

[0117] Figure 10 is a conceptual diagram illustrating the beam gain according to the electromagnetic wave region where the terminal is located when beam sweeping is performed using a far-field beam.

[0118] Referring to FIG. 10, when a terminal is located in a far-field (for example, when a base station and a terminal communicate via a far-field path), the beam gain at the terminal may have a large value only in a specific direction. When the electromagnetic field between the base station and the terminal is defined as a far-field, the angle at which the terminal is located can be accurately estimated through far-field beam sweeping.

[0119] When a terminal is located in a near-field (e.g., when the base station and the terminal communicate via a near-field path), there may not be a specific direction in which the terminal exhibits high beam gain, making it difficult for the base station to determine the terminal's exact orientation. By performing far-field beam sweeping, the base station can estimate an approximate angular region (e.g., an angular domain) where the terminal is likely to be located, even if it cannot estimate the terminal's precise angle. This is because a valid signal strength is detected at the receiver even when a far-field beam is used for a near-field path (e.g., a scatterer forming the near-field path).

[0120] In the embodiment of FIG. 10, when a far-field beam is used in a near-field path, a phenomenon may occur in which the signal strength at the receiver is distributed over a specific angular region. Based on this beam gain spreading phenomenon, the communication node can not only detect the existence of a far-field path through a far-field beam management procedure, but also limit the angular region where a near-field path is likely to exist.

[0121] - Beam management procedures in communication systems (e.g., legacy communication systems)

[0122] In a communication system, beam management procedures can be performed based on the procedures defined in Table 2 below.

[0123]

[0124] In the present disclosure, the transmission (Tx) beam of a base station may be referred to as a BS (base station) beam or a TRP (transmission and reception point) beam, and the reception (Rx) beam of a terminal may be referred to as a terminal beam or a UE (user equipment) beam. In a communication system (e.g., a 5G communication system), the beam management procedure may be divided into a first step (P1), a second step (P2), and a third step (P3). In the present disclosure, P1 may mean P1 defined in Table 2, P2 may mean P2 defined in Table 2, and P3 may mean P3 defined in Table 2.

[0125] In P1, the base station can sweep the BS beam (e.g., the transmitting beam), and the terminal can sweep the UE beam (e.g., the receiving beam) to receive a signal transmitted from the base station. In P1, the terminal can select the BS beam that provides the best performance based on the reception performance measured through its UE beam, and can report information about the selected BS beam to the base station. The base station can receive information about the BS beam selected by the terminal. In P2, the base station can refine its BS beam based on the information (e.g., the BS beam) obtained from the terminal in P1. Subsequently, in P3, the terminal can refine its UE beam based on the BS beam refined by the base station in P2 to select the optimal UE beam.

[0126] The process of the terminal selecting the optimal BS beam at P1 can be performed as a necessity. Since only one BS-UE beam pair is selected at P1 defined in the communication system, there may be a limitation in that it is difficult to simultaneously search for multiple paths in a multipath environment. In particular, in environments where near-field and far-field paths are mixed, such as in a hybrid field environment, the limitations of the existing beam management procedure may become even more pronounced.

[0127] When the base station and the terminal perform beam sweeping using a far-field beam at P1, the optimal BS-UE beam pair selected at P1 can be determined as a beam corresponding to the far-field path. This is because, even if a near-field path exists, it is difficult for the near-field path to provide superior reception performance compared to the far-field path through far-field beam sweeping alone due to the beam gain dispersion effect.

[0128] To solve the aforementioned problem (e.g., to detect far-field paths and near-field paths together), a method of performing both far-field beam sweeping and near-field beam sweeping at P1 may be considered. Since this method requires beam sweeping for all possible combinations of angle and distance, excessive overhead may be induced. A method to effectively detect near-field paths while minimizing overhead may be required. To this end, a method will be proposed to limit the angular region where a near-field path is likely to exist by utilizing the beam gain dispersion effect that occurs when far-field beam sweeping is applied to a near-field path, and to perform near-field beam management for the limited angular region.

[0129] A method for selecting an optimal path for communication between a base station and a terminal in a multipath hybrid field environment will be described. In a multipath hybrid field environment, a path between a base station and a terminal can be represented by a combination of a transmitting beam of one base station (e.g., a BS beam) and a receiving beam of one terminal corresponding to said transmitting beam (e.g., a UE beam). Searching for an optimal path between a base station and a terminal may have the same meaning as searching for an optimal pair of BS beams and optimal UE beams. In the present disclosure, a BS-UE beam pair can be interpreted as a BS beam from the base station's perspective, and a BS-UE beam pair can be interpreted as a UE beam from the terminal's perspective. In other words, a BS-UE beam pair can be interpreted as a BS beam, a UE beam, or a BS-UE beam pair depending on the context.

[0130] To search for (e.g., determine, select) the optimal BS-UE beam pair, the base station and the terminal can perform beam sweeping using far-field beams. Beam sweeping using far-field beams may correspond to P1. In P1, the terminal can measure reception performance by receiving each BS beam of the base station as its own each UE beam, and can record the measured performance. The terminal can measure the reference signal received power (RSRP) for all far-field BS-UE beam combinations. The set of RSRP measurement information for all far-field BS-UE beam combinations can be defined as an RSRP map. The RSRP map may be referred to as a reception performance map.

[0131] The terminal can report to the base station a BS beam corresponding to the BS-UE beam combination (e.g., BS-UE beam pair) having the largest RSRP in the RSRP map, and subsequently, P2 and P3 can be performed sequentially. In a multipath hybrid field environment, since beam management procedures for near-field paths must be additionally considered, a procedure for detecting paths based on the RSRP map may be further required. To this end, the base station can determine path selection criteria for detecting far-field and near-field paths based on the RSRP map. The base station can transmit information on the path selection criteria to the terminal via signaling. The procedure for determining a path by applying path selection criteria to the RSRP map can be selectively performed by either the base station or the terminal.

[0132] When a path determination procedure (e.g., a path selection procedure) is performed at a base station, the terminal can transmit the RSRP map measured at P1 to the base station, and the base station can determine a path based on the RSRP map received from the terminal and perform subsequent procedures after determining the path. When a path determination procedure (e.g., a path selection procedure) is performed at a terminal, the base station can transmit path selection criteria to the terminal. The terminal can determine a path by applying the path selection criteria received from the base station to the RSRP map and report information about the determined path to the base station.

[0133] After the path determination procedure, the base station and the terminal can refine each beam by performing P2 and P3 for each path. For example, for a far-field path, the communication node (e.g., base station, terminal) can perform beam sweeping in the angle domain using a narrow beam. For a near-field path, the communication node can select the optimal near-field beam by performing beam sweeping in the distance domain and the angle domain.

[0134] In the present disclosure, RSRP may be considered as a communication performance indicator for selecting the combination of transmit and receive beams between a base station and a terminal. In the procedure for beam selection (e.g., beam determination), other communication performance indicators such as RSRQ (Reference Signal Received Quality) and CQI (Channel Quality Indicator) may be utilized instead of RSRP. The transmit and receive beams of the base station and the terminal may be classified as far-field beams or near-field beams depending on the path. The "determination of near-field paths and angle domain restriction through far-field beam sweeping," which is used as a path selection criterion, may be based on the beam gain dispersion phenomenon that occurs when far-field beams are used in a near-field path. The base station may also use path selection criteria other than the method utilizing the beam gain dispersion phenomenon. The base station may determine far-field paths and near-field paths based on the above path selection criteria, and then perform beam management in a multipath hybrid field environment based on the procedure defined in the present disclosure.

[0135] In this disclosure, methods are proposed to enable a base station and a terminal to efficiently select an optimal transmit-receive beam combination in a multipath hybrid field environment by extending a legacy beam management procedure. The legacy beam management procedure may be a procedure for determining an optimal far-field path. In this disclosure, a communication node may determine a near-field path with low complexity based on the results of legacy beam management. The communication node may finally determine the optimal path (e.g., transmit-receive beam combination) in a hybrid field environment by comparing the results for the near-field path with the results for the far-field path.

[0136] A method for searching for a near-field path based on legacy beam management results can be performed as follows. A terminal can measure the RSRP for all far-field BS-UE beam combinations by sweeping its far-field UE beam against the base station's different far-field BS beams. The above procedure may correspond to P1, and the terminal can organize the measurement results in the form of an RSRP map. Subsequently, the communication node can determine a far-field path (e.g., a far-field beam pair) using the RSRP map and estimate the approximate range where a near-field path is likely to exist. By repeatedly performing P2 and P3 for each path, the communication node can refine the transmit-receive beams corresponding to each path and select the optimal path.

[0137] Specifically, in a hybrid field environment, the beam management procedure may include the following three detailed procedures.

[0138] (i) Exchange of prior information necessary to perform beam management procedures in a hybrid field

[0139] (ii) Joint far-field beam sweeping (P1) between base station and terminal

[0140] (iii) Near-field beam sweeping of the base station (P2) and near-field beam sweeping of the terminal (P3)

[0141] (i) In the preliminary information exchange procedure, the conditions under which a beam management procedure is initiated in a hybrid field environment, and the reporting and resource settings for operation after the beam management procedure is initiated in a hybrid field environment may be defined. Since RSRP map-based path determination and iterative search for the determined paths may be performed in this disclosure, newly introduced parameters, such as path selection criteria, and the method of setting said parameters may be defined.

[0142] (ii) In the joint far-field beam sweeping (P1) between the base station and the terminal, the operation of the terminal setting an RSRP map based on P1, and the operation of the base station or the terminal determining a far-field path and a near-field path using the RSRP map will be proposed. The terminal may set an RSRP map and transmit the RSRP map to the base station. Alternatively, the terminal may determine a valid far-field path and a near-field path using path selection criteria received from the base station and transmit the determined path information to the base station. The path may be determined by applying the path selection criteria to the RSRP map.

[0143] (iii) In the near-field beam sweeping (P2) of the base station and the near-field beam sweeping (P3) of the terminal, the base station and the terminal can determine the optimal transmit-receive beam combination for each path by performing beam search in the distance domain. The above operation can be repeated for each determined path. The base station and the terminal can finally determine the optimal transmit-receive beam combination by comparing the results for the near-field path and the results for the far-field path.

[0144] The operation of determining the optimal transmit-receive beam combination for a single path may correspond to P2 and P3 defined in Table 2. In this disclosure, P2 and P3 may be repeated as many times as the number of paths determined in the previous step. Despite the repetition of P2 and P3, the method proposed in this disclosure can achieve lower computational complexity and less resource consumption compared to a method of transmitting all possible near-field beams in batches.

[0145] - Procedure for exchanging preliminary information required for beam management procedures in a hybrid field

[0146] In a hybrid field, beam management procedures may be an extension of existing beam management procedures. The overall operation of beam management procedures in a hybrid field may differ from existing beam management procedures. Prior agreement between the base station and the terminal regarding whether to perform beam management procedures in a hybrid field may be required. The base station may decide whether to perform beam management procedures in a hybrid field based on prior information it possesses. The base station may determine how to perform hybrid field beam management based on information such as RSRP map creation capability and carrier frequency obtained from the terminal's UE capability response. RSRP map creation capability may correspond to information regarding whether the terminal is configured with multiple antennas. If the base station decides to perform beam management procedures in a hybrid field, the base station may configure the terminal to be suitable for beam management in the hybrid field and transmit parameters used in subsequent operations to the terminal.

[0147]

[0148] The base station may transmit system information (SI) containing BeamManagementInfo to the terminal. The method of executing the beam management procedure may be determined based on the BeamManagementInfo included in the SI. The BeamManagementInfo may include a fieldType. The fieldType may be set to far, near, hybrid, or unknown. The fieldType may indicate which electromagnetic field corresponds to the initiation of the beam management procedure. In other words, the fieldType may indicate the initiation of a far-field beam management procedure (e.g., legacy beam management procedure), a near-field beam management procedure, or a hybrid-field beam management procedure. A hybrid-field beam management procedure may include both a far-field beam management procedure and a near-field beam management procedure. The terminal may determine which electromagnetic field corresponds to the initiation of the beam management procedure based on the information indicated by the fieldType. BeamManagementInfo may be added as a new parameter to an MIB or SIB1. A new SIB containing BeamManagementInfo may be defined. The base station can transmit beam management information to the terminal by transmitting a new SIB to the terminal.

[0149] If the field type indicates far, the communication node may perform existing beam management procedures (e.g., legacy beam management procedures). If the field type indicates near, the communication node may perform near-field beam management procedures without performing legacy beam management procedures. In other words, legacy beam management procedures may be omitted. If the base station determines that the electromagnetic field between itself and the terminal is a hybrid field, the base station may set the field type to hybrid and perform operations based on the information defined in Table 4. If the field type indicates hybrid, the communication node may perform hybrid field beam management procedures. The beam management procedures corresponding to each electromagnetic field may be treated as equivalent to legacy beam management procedures and may be performed optionally.

[0150] If there is insufficient prior information regarding the current radio environment during the initial connection phase, or if the radio environment changes rapidly and is difficult to predict, the base station may set the field type to unknown. When the field type indicates unknown, the terminal may determine that it performs both the far-field beam management procedure and the near-field beam management procedure unless additional instructions are received from the base station.

[0151]

[0152] The terminal may transmit its reporting capability (e.g., UE reporting capability) to the base station via a UE capability response (e.g., the UE capability response specified in Table 4). The base station may receive the UE capability response from the terminal and determine detailed procedures for beam management in the hybrid field based on the UE reporting capability indicated by the UE capability response. The UE reporting capability may indicate whether the terminal can report an RSRP map. The base station may transmit a UE capability request to the terminal separately from the field type setting. If a UE capability request is received from the base station, the terminal may transmit a UE capability response containing the UE reporting capability to the base station. The base station may determine a path selection method (e.g., path determination method) based on the UE reporting capability indicated by the UE capability response received from the terminal.

[0153] If the terminal does not have the ability to simultaneously report RSRP measurement results for multiple BS-UE beam pairs (e.g., if the terminal does not have the ability to report an RSRP map), the base station may transmit path selection criteria to the terminal, and the terminal may select (e.g., determine) a path based on the RSRP map using the path selection criteria indicated by the base station. The terminal may transmit information about the selected path to the base station via signaling. The base station may receive information about the selected path via the terminal's signaling. If the terminal has the ability to simultaneously report RSRP measurement results for multiple BS-UE beam pairs (e.g., if the terminal has the ability to report an RSRP map), the terminal may generate an RSRP map and transmit it to the base station, and the base station may select (e.g., determine) a path based on the RSRP map received from the terminal. The base station may transmit information about the selected path to the terminal via signaling. The terminal may receive information about the selected path via the base station's signaling.

[0154] The base station can determine detailed procedures for beam management in the hybrid field by comprehensively considering UE capability information (e.g., information included in the UE capability response), including the maximum number of UE beams that the terminal can form.

[0155]

[0156] A base station may transmit ReportingInfo to a terminal via signaling. A terminal may receive ReportingInfo via the base station's signaling. ReportingInfo may include parameter(s) used to determine the information that the terminal reports to the base station. ReportingInfo may be added as a new parameter to an MIB or SIB1. A new SIB containing ReportingInfo may be defined. The base station may deliver ReportingInfo to the terminal by transmitting the new SIB to the terminal.

[0157] Report information may include one or more parameters specified in Table 5. For example, report information may include at least one of report configuration, report topN, or RSRP threshold. Report configuration may mean ssb-reportConfiguration. Report topN may mean ssb-reportTopN. RSRP threshold may mean ssb-rsrpThreshold. Report configuration may indicate whether the terminal transmits the results of measuring the base station's BS beam with its own UE beam (e.g., measurement results for far-field beam sweeping) based on individual reporting for each BS-UE beam pair or collective reporting for all BS-UE beam pairs (e.g., RSRP map). In other words, report configuration may indicate the method of reporting measurement results.

[0158] If the reporting setting is set to individual, the terminal can report the measurement results for the BS-UE beam pair with the best reception performance to the base station. Alternatively, if the reporting setting is set to individual, the terminal can individually report the measurement results for the top N BS-UE beam pairs based on reception performance criteria. N can be a natural number. N can be indicated by the reporting target. If the reporting setting is set to map, the terminal can transmit the reception performance of all BS-UE beam pairs it has measured to the base station in the form of an RSRP map.

[0159] The reporting target may indicate how many BS-UE beam pairs the terminal reports reception performance to the base station. If the reporting setting is set individually, the reporting target may be set to an integer from 1 to 8. Alternatively, the reporting target may be set to an integer greater than 8. The terminal may report measurement results for the top N BS-UE beam pairs based on reception performance criteria to the base station. If the reporting setting is set to a map, the reporting target may be set to All. In this case, the terminal may transmit the RSRP map to the base station after P1.

[0160] The RSRP threshold may indicate the RSRP reference value (e.g., RSRP threshold) of a BS-UE beam pair to be reported to the base station. The terminal may report BS-UE beam pair(s) having an RSRP greater than or equal to the RSRP threshold to the base station. The RSRP threshold may be set as an integer between 0 and 100. An integer between 0 and 100 may correspond to any dBm value. The RSRP threshold may be set as any dBm value between -80 dBm and -120 dBm.

[0161] RSRP thresholds can be used as path selection criteria for beam management in hybrid field environments. In addition to RSRP thresholds, other reception performance indicators can also be utilized as path selection criteria. To more effectively distinguish each path in a multipath environment, path-specific RSRP, which represents the received signal strength for each path, can be used as an RSRP reference value (e.g., RSRP threshold). In addition to reception performance indicators, angle information such as AOA (angle of arrival) can also be utilized as a path selection criterion. To support the above-described operation, the base station may transmit report information to the terminal that includes an angle threshold or an angle range. The angle threshold may refer to ssb-angleThreshold. The angle range may refer to ssb-angleRange. The terminal can receive report information from the base station and check the angle threshold or angle range included in the report information. The terminal can change the direction of the BS beam and the UE beam, respectively, by angle. The terminal can determine that a signal having a difference greater than an angle threshold (e.g., a signal outside the angle range) is a signal transmitted through different paths.

[0162] RSRP thresholds and / or angle thresholds are used as path selection criteria, and if no valid path exists, the base station and the terminal may not perform path selection and may perform legacy beam management procedures. Retry criteria for the path selection operation may be pre-set and may be included in the path selection criteria. For example, the RSRP threshold may be set to be relaxed by a certain percentage (e.g., half), a research operation may be performed based on the relaxed RSRP threshold, and beam management procedures may be performed using the retry criteria.

[0163] The examples in Table 5 may be intended to illustrate simple examples of path selection criteria. Detailed examples of path selection criteria used in actual beam management procedures may be provided in Table 8. The path selection criteria specified in Table 8 may be included in the reporting information.

[0164] - Joint far-field beam sweeping between base station and terminal (P1)

[0165] Figure 11 is a conceptual diagram illustrating joint far-field beam sweeping between a base station and a terminal.

[0166] Referring to FIG. 11, in a joint far-field beam sweeping procedure, a base station may perform beam sweeping using a formable far-field BS beam, and a terminal may receive a far-field BS beam using a formable far-field UE beam. Joint far-field beam sweeping may correspond to P1. In the present disclosure, the signals transmitted and received in the beam sweeping procedure may be SSB and / or DL ​​RS (downlink reference signal). DL RS may be CSI-RS, DM-RS, PL (pathloss)-RS, etc. In the present disclosure, transmitting a beam may mean transmitting a signal through said beam, and receiving a beam may mean receiving a signal through said beam. The terminal may generate an RSRP map based on the measurement results of joint far-field beam sweeping. The RSRP map may be referred to as a reception performance map, a measurement result map, etc. A base station or terminal can determine valid far-field paths and valid near-field path(s) by applying path selection criteria to an RSRP map. Table 6 below may be an example of an RSRP map.

[0167]

[0168] In Table 6, RSRP_x may mean -x dBm. For example, RSRP_78 may mean -78 dBm, RSRP_108 may mean -108 dBm, and RSRP_115 may mean -115 dBm. In an embodiment based on Table 6, the base station may perform beam sweeping using 10 BS beams (e.g., far-field BS beams), and the terminal may perform beam sweeping using 5 UE beams (e.g., far-field UE beams). The RSRP map in Table 6 may represent the RSRP performance for each BS-UE beam pair measured by the terminal. The RSRP map may be constructed based on the combination of beam indices of all BS-UE beam pairs and the RSRP corresponding to each BS-UE beam pair. In the RSRP map of Table 6, the RSRPs of {BS Beam #3, UE Beam #1}, {BS Beam #7, UE Beam #4}, {BS Beam #7, UE Beam #5}, {BS Beam #8, UE Beam #4}, and {BS Beam #8, UE Beam #5} can be relatively high. From an RSRP perspective, {BS Beam #3, UE Beam #1}, {BS Beam #7, UE Beam #4}, {BS Beam #7, UE Beam #5}, {BS Beam #8, UE Beam #4}, and {BS Beam #8, UE Beam #5} can be considered potential candidate paths. {BS Beam #X, UE Beam #Y} can be a BS Beam #X-UE Beam #Y pair. X and Y can each be natural numbers.

[0169] The base station may perform beam management procedures to determine a valid path. The terminal may transmit an RSRP map (e.g., information on the RSRP map) to the base station via signaling. The base station may receive the RSRP map (e.g., information on the RSRP map) via the terminal's signaling. The information included in the RSRP map and the reporting method of the RSRP map may be determined based on the RSRP map reporting format defined in Table 7 below.

[0170]

[0171] The base station may decide to perform a path selection procedure. To support the base station's path selection procedure, the terminal may transmit the RSRP map it has measured to the base station. To enable the terminal to transmit the RSRP map to the base station, the measurement report may include parameter(s) for reporting the RSRP map. Alternatively, new signaling for the parameter(s) for reporting the RSRP map may be defined.

[0172] The RSRP map reporting format may include at least one of a BS-UE beam index, a performance metric, segmentation information, or a report type. Table 7 may be an RSRP map reporting format established based on measurement reporting for legacy beam management procedures. Table 7 may be an extended form of measurement reporting for legacy beam management procedures. Table 7 may have a structure of measurement reporting that includes measurement information for combinations of multiple BS-UE beam indices. The performance metric included in the RSRP map reporting format may indicate the RSRP and / or measurement time. The measurement information may include the RSRP. Additionally, the measurement information may further include information regarding the measurement time.

[0173] The RSRP map may contain a large amount of information depending on the number of far-field beams used by the base station and the terminal at P1. The terminal may divide the RSRP map into multiple measurement reports and transmit them. The division information included in the RSRP map report format may indicate whether to divide and transmit the RSRP map. If the division information is set to False, the terminal may generate a single measurement report containing all information of the RSRP map and transmit said single measurement report to the base station. If the division information is set to True and the number of divisions of the RSRP map is indicated to the terminal, the terminal may divide the RSRP map into a number corresponding to the number of divisions and transmit the divided RSRP map to the base station. Information indicating the number of divisions of the RSRP map may be included in the RSRP map report format. In another embodiment, if the division information is set to True, the terminal may divide the RSRP map into a number corresponding to a preset number of divisions (e.g., default number of divisions) and transmit the divided RSRP map to the base station.

[0174] The report type included in the RSRP map report format can indicate the reporting method of the RSRP map. If the report type is set to Periodically, the terminal can transmit the RSRP map to the base station periodically. If the report type is set to Event-triggered, the terminal can transmit the RSRP map to the base station when a specific event occurs. For example, if the report type is set to Event-triggered, the terminal can transmit the RSRP map to the base station after the completion of P1.

[0175] In another embodiment, when a terminal performs a beam management procedure to determine a valid path, the terminal may not transmit an RSRP map to the base station and may perform a path selection procedure based on the parameter(s) defined in Table 5. Table 8 below may be a path selection criterion used by the base station and / or terminal to determine a valid path.

[0176]

[0177] Path Selection Criterion may be included in the report information. Path Selection Criterion may be referred to as Path Determination Criterion. Path Selection Criterion may mean Beam Pair Selection Criterion or Beam Pair Determination Criterion. Path may have a meaning corresponding to Beam Pair. In beam management procedures in a hybrid field environment, two or more RSRP thresholds (e.g., Far Field RSRP threshold, Near Field RSRP threshold) may be set to effectively distinguish between far-field paths (e.g., Far Field Beam Pairs) and near-field paths (e.g., Near Field Beam Pairs). A base station may generate a path selection criterion containing multiple RSRP thresholds and transmit the path selection criterion (e.g., Report Information containing the path selection criterion) to a terminal via signaling. The far-field RSRP threshold may be set to a value relatively larger than the near-field RSRP threshold. RSRP_80 may mean -80dBm, and RSRP_100 may mean -100dBm.

[0178] A communication node (e.g., a base station or a terminal) performing a path selection procedure may determine a BS-UE beam pair having an RSRP greater than or equal to a far-field RSRP threshold as a far-field path (e.g., a far-field beam pair). The far-field path determined by the communication node may be a valid far-field path. The communication node may determine a BS-UE beam pair having an RSRP less than the far-field RSRP threshold and greater than or equal to a near-field RSRP threshold as a near-field path (e.g., a near-field beam pair). The near-field path determined by the communication node may be a valid near-field path. When a base station performs a path selection procedure, the base station may select a far-field path and a near-field path by applying path selection criteria to an RSRP map received from a terminal. When a terminal performs a path selection procedure, the terminal may select a valid path (e.g., a valid far-field path and a valid near-field path) using path selection criteria (e.g., path selection criteria included in report information) and transmit information of the valid path to the base station through signaling. The base station can receive information on a valid path through the terminal's signaling. Information on a valid path may be included in the measurement report transmitted by the terminal.

[0179] To establish sophisticated path selection criteria, additional parameter(s) may be introduced in addition to the RSRP threshold. If many paths (e.g., many valid paths) are selected based on the RSRP threshold, the overhead at P2 and P3 may be significant. To address the aforementioned problem, the maximum number of valid paths may be limited. Furthermore, multiple RSRP thresholds may be set, and the communication node performing the path selection procedure may use an appropriate RSRP threshold by considering the number of valid paths to be selected. The "Maximum number of paths" included in the path selection criteria may indicate the maximum number of valid paths. In other words, the maximum number of paths may indicate the maximum number of selectable valid paths. The communication node may select valid paths up to or less than the maximum number of paths. Based on the above method, the number of valid paths can be adjusted, and the beam management procedure can be completed efficiently.

[0180] Path selection criteria may include a path selection timer. According to the path selection timer, the maximum overhead of the beam management procedure in the hybrid field may be limited. If the path selection timer is set, the communication node may use the valid paths selected within the time corresponding to the path selection timer. If no valid path is selected within the time corresponding to the path selection timer, the communication node may perform the legacy beam management procedure. The time corresponding to the path selection timer may refer to the time during which the path selection procedure is performed.

[0181] Figure 12 is a conceptual diagram illustrating an RSRP map.

[0182] The RSRP map illustrated in FIG. 12 may be an RSRP map based on Table 6. Referring to FIG. 12, the BS-UE beam pair (1210) may be {BS beam #3, UE beam #1}. The BS-UE beam pair (1220) may be {BS beam #7, UE beam #4}, {BS beam #7, UE beam #5}, {BS beam #8, UE beam #4}, and {BS beam #8, UE beam #5}. Table 9 below may show paths (e.g., valid paths) determined based on the RSRP map.

[0183]

[0184] The paths in Table 9 can be determined by applying path selection criteria to the RSRP map. A communication node can determine {BS Beam #3, UE Beam #1}, which has an RSRP greater than or equal to the far-field RSRP threshold, as Path 1, which is a far-field path. A communication node can determine {BS Beam #7, UE Beam #4}, {BS Beam #7, UE Beam #5}, {BS Beam #8, UE Beam #4}, and {BS Beam #8, UE Beam #5}, which have an RSRP less than the far-field RSRP threshold and greater than or equal to the near-field RSRP threshold, as Path 2, which is a near-field path. In the RSRP map, if BS-UE beam pairs having an RSRP less than the far-field RSRP threshold and greater than or equal to the near-field RSRP threshold are adjacent, the BS-UE beam pairs can be defined as a BS-UE beam group, and the BS-UE beam group can be designated as a single path.

[0185] - Near-field beam sweeping of the base station (P2) and near-field beam sweeping of the terminal (P3)

[0186] Figure 13 is a conceptual diagram illustrating angle and distance domain beam sweeping for a near-field path to find the optimal BS beam.

[0187] Referring to FIG. 13, a base station may perform near-field beam sweeping (P2) on path(s) (e.g., one or more near-field paths) detected in P1. Near-field beam sweeping may be a procedure for determining (e.g., refining) the optimal BS beam and the optimal UE beam. In P2, the UE beam may be fixed for a specific path, and the optimal BS beam may be determined through BS beam sweeping. In P3, the optimal UE beam may be determined through UE beam sweeping by considering the optimal BS beam determined through P2. P2 and P3 may be repeated for all paths. A communication node may determine the optimal near-field beam pair (e.g., the optimal BS-UE beam pair) by comparing the results for each path.

[0188] In Table 9, the near-field beam pairs may be {BS beam #7, UE beam #4}, {BS beam #7, UE beam #5}, {BS beam #8, UE beam #4}, and {BS beam #8, UE beam #5}. In P2, the base station may transmit a signal by sweeping BS beam #7 and BS beam #8, respectively, and the terminal may perform a measurement on the swept BS beam (e.g., a signal received through the swept BS beam) using UE beam #4. In P2, the base station may transmit a signal by sweeping BS beam #7 and BS beam #8, respectively, and the terminal may perform a measurement on the swept BS beam (e.g., a signal received through the swept BS beam) using UE beam #5. The beam sweeping procedure in P2 may be performed by transmitting beams at different distances from a specific angle. In other words, the beam sweeping procedure of P2 may be an angle-distance domain beam sweeping procedure. The measurement results for the BS beams based on UE beam #4 may be as shown in Table 10 below.

[0189]

[0190] The measurement results for the BS beams based on UE beam #5 may be as shown in Table 11 below.

[0191]

[0192] In each of BS Beam #7-P and BS Beam #8-P, P may represent the distance from the base station. P may be a natural number. If P is set to a value from 1 to 4, P=1 may indicate the closest distance from the base station, and P=4 may indicate the farthest distance from the base station. In each of Tables 10 and 11, the BS Beam Index may be expressed by connecting the Angle Index (7, 8) and the Distance Index (1, 2, 3, 4) with a dash (-). In another embodiment, the BS Beam Index may be expressed by concatenating the binary value of the Angle Index (7, 8) and the binary value of the Distance Index (1, 2, 3, 4). In the embodiments of Tables 10 and 11, BS Beam #7-3 (e.g., BS Beam #7-3 corresponding to UE Beam #4) may have the best RSRP. In other words, the communication node can determine BS beam #7-3 as the optimal BS beam.

[0193] FIG. 14 is a conceptual diagram illustrating angle and distance domain beam sweeping for a near-field path to find the optimal UE beam.

[0194] Referring to FIG. 14, the terminal can perform near-field beam sweeping (P3) on path(s) (e.g., one or more near-field paths) detected in P1. Near-field beam sweeping may be a procedure for determining (e.g., refining) the optimal BS beam and the optimal UE beam. In P2, the UE beam for a specific path may be fixed, and the optimal BS beam may be determined through BS beam sweeping. In P3, the optimal UE beam may be determined through UE beam sweeping by considering the optimal BS beam determined through P2. P2 and P3 may be repeated for all paths. The communication node may determine the optimal near-field beam pair (e.g., the optimal BS-UE beam pair) by comparing the results for each path.

[0195] If BS beam #7-3 is determined to be the optimal BS beam in P2, the measurement results for UE beams based on BS beam #7-3 may be as shown in Table 12 below.

[0196]

[0197] In each of UE Beam #4-L and UE Beam #5-L, L may represent the distance from the terminal. L may be a natural number. When L is set to a value from 1 to 4, L=1 may indicate the closest distance from the terminal, and L=4 may indicate the farthest distance from the terminal. In Table 12, the UE beam index may be expressed by connecting the angle index (4, 5) and the distance index (1, 2, 3) with a dash (-). In another embodiment, the UE beam index may be expressed by concatenating the binary values ​​of the angle index (4, 5) and the distance index (1, 2, 3). In the embodiment of Table 12, UE Beam #4-2 (e.g., UE Beam #4-2 corresponding to BS Beam #7-3) may have the best RSRP. In other words, the communication node may determine UE Beam #4-2 as the optimal UE beam.

[0198] For each of the paths 2 (e.g., near-field paths) in Table 9, P2 and P3 can be performed, and the communication node can determine the optimal near-field path as {BS beam #7-3, UE beam #4-2}. Based on the example in Table 6, the communication node can determine the optimal far-field path as {BS beam #3, UE beam #1}. Alternatively, the communication node can determine {BS beam #3b, UE beam #1a} as the optimal far-field path by performing a refinement procedure on {BS beam #3, UE beam #1}.

[0199]

[0200] A communication node can compare the RSRP of the optimal far-field path having the largest RSRP in Path 1 (e.g., far-field path) with the RSRP of the optimal near-field path having the largest RSRP in Path 2 (e.g., near-field path), and can determine the path having the largest RSRP among the optimal far-field path and the optimal near-field path as the final path. In the embodiment of Table 13, since the RSRP of Path 2 (e.g., near-field path) is greater than the RSRP of Path 1 (e.g., far-field path), the communication node can determine {BS Beam #7-3, UE Beam #4-2} as the final path. Since the near-field path is selected as the final path, the most dominant path between the base station and the terminal can be determined to be the near-field path. The communication node can perform communication through the final path (e.g., {BS Beam #7-3, UE Beam #4-2}).

[0201] Figure 15 is a flowchart illustrating the beam sweeping procedure in a hybrid field environment.

[0202] Referring to FIG. 15, the base station and the terminal can exchange configuration information for a beam management procedure (e.g., information required for a hybrid field-beam management (HBF-BM) procedure) (S1510). In S1511, the base station can transmit system information to the terminal that includes beam management information (BeamManagementInfo) specified in Table 3. In S1511, the terminal can receive system information from the base station, check the beam management information included in the system information, and determine which beam management procedure (e.g., near-field beam management procedure, far-field beam management procedure, hybrid field beam management procedure) is performed based on the beam management information.

[0203] In S1512, the terminal may transmit a UE capability response specified in Table 4 to the base station, and the base station may receive a UE capability response from the terminal. In another embodiment, in S1512, the base station may transmit a UE capability request to the terminal, and the terminal may transmit a UE capability response to the base station in response to the base station's UE capability request. The UE capability response may include information indicating whether the terminal has the capability to simultaneously report RSRP measurement results for multiple beam pairs. The information may indicate whether the terminal can transmit an RSRP map.

[0204] In S1513, the base station may transmit system information to the terminal that includes reporting information defined in Table 5. The reporting information may include path selection criteria defined in Table 8. In S1513, the terminal may receive system information from the base station and verify the reporting information included in the system information. The reporting information may include parameter(s) used to determine the information that the terminal reports to the base station. For example, the reporting information may include at least one of report configuration, report topN, or RSRP threshold. Additionally, the reporting information may further include path selection criteria.

[0205] The base station and the terminal can perform a joint far-field beam sweeping procedure (S1520). S1520 can be performed based on the configuration information exchanged in S1510. In S1521, the base station can transmit a signal (e.g., SSB, DL RS) to the terminal via beam sweeping, and the terminal can measure the RSRP for the signal received from the base station. The terminal can generate an RSRP map based on the measured RSRP. In S1522, if the terminal has the ability to transmit the RSRP map to the base station, the terminal can transmit the RSRP map to the base station, and the base station can receive the RSRP map from the terminal.

[0206] When an RSRP map is received from a terminal, in S1523, the base station can determine valid path(s) by applying path selection criteria to the RSRP map and transmit information of the valid path(s) to the terminal. In S1523, if the terminal does not have the ability to transmit the RSRP map to the base station, the terminal can determine valid path(s) by applying path selection criteria to the RSRP measurement results and transmit information of the valid path(s) to the base station. Information of the valid path(s) can be exchanged between the base station and the terminal. The valid path(s) may include valid long-field paths and valid short-field path(s).

[0207] The base station and the terminal can perform a near-field beam sweeping procedure for valid path(s) (e.g., valid near-field path(s)) (S1530). S1530 can be performed based on configuration information exchanged in S1510. In S1531, the base station can perform angle-distance domain beam sweeping for one or more BS beams, and the terminal can measure the RSRP for the swept beams based on a specific UE beam. In S1531, the communication node can determine the optimal BS beam based on the RSRP measurement result. In S1532, the base station can transmit the optimal BS beam determined in S1531, and the terminal can measure the RSRP by sweeping the UE beams. In S1532, the communication node can determine the optimal UE beam based on the RSRP measurement result. The BS beam-UE beam pair determined in S1531 and S1532 may be the optimal near-field beam pair (e.g., the optimal near-field path). Information on optimal near-field beam pairs can be exchanged between the base station and the terminal. The communication node can determine the optimal far-field beam pair (e.g., optimal far-field path) by performing a refinement procedure on valid far-field beam pairs. Information on the optimal far-field beam pairs can be exchanged between the base station and the terminal.

[0208] In S1533, the communication node can determine the final beam pair (e.g., the final path) by comparing the RSRP of the optimal far-field beam pair with the RSRP of the optimal near-field beam pair. If the RSRP of the optimal far-field beam pair is greater than the RSRP of the optimal near-field beam pair, the communication node can determine the optimal far-field beam pair as the final beam pair. If the RSRP of the optimal near-field beam pair is greater than the RSRP of the optimal far-field beam pair, the communication node can determine the optimal near-field beam pair as the final beam pair. Information regarding the final beam pair can be exchanged between the base station and the terminal. The communication node can perform communication using the final beam pair.

[0209] Simple combinations, partial combinations, and / or extended combinations of two or more of the embodiments described above (e.g., methods, ways) may be possible. Some of the embodiments described above may be omitted. In other words, some embodiments may be performed optionally.

[0210] The operation of the method according to the present disclosure can be implemented as a computer-readable program or code on a computer-readable recording medium. A computer-readable recording medium includes any type of recording device in which information that can be read by a computer system is stored. Additionally, a computer-readable recording medium may be distributed across networked computer systems, allowing the computer-readable program or code to be stored and executed in a distributed manner.

[0211] In addition, computer-readable recording media may include hardware devices specifically configured to store and execute program instructions, such as ROM, RAM, and flash memory. Program instructions may include machine code, such as that generated by a compiler, as well as high-level language code that can be executed by a computer using an interpreter, etc.

[0212] Some aspects of the present disclosure have been described in the context of a device, but may also be described according to a corresponding method, wherein a block or device corresponds to a method step or a feature of a method step. Similarly, aspects described in the context of a method may also be described according to a corresponding block or item or a feature of a corresponding device. Some or all of the method steps may be performed by (or using) a hardware device, such as, for example, a microprocessor, a programmable computer, or an electronic circuit. In some embodiments, at least one of the most important method steps may be performed by such a device.

[0213] A programmable logic device (e.g., a field-programmable gate array) may be used to perform some or all of the functions of the methods described in this disclosure. A field-programmable gate array may operate with a microprocessor to perform one of the methods described in this disclosure. Generally, it is preferable that the methods be performed by some hardware device.

[0214] Although the present disclosure has been described with reference to preferred embodiments, those skilled in the art will understand that various modifications and changes can be made to the present disclosure without departing from the spirit and scope of the present disclosure as set forth in the following claims.

Claims

1. As a method of UE (user equipment), A step of receiving configuration information for a beam management procedure from a base station; A step of performing a first measurement operation for the far-field beam of the base station based on the above setting information; A step of determining an optimal far-field beam pair based on the result of the first measurement operation above; A step of performing a second measurement operation on one or more near-field beam pairs determined based on the result of the first measurement operation; A step of determining an optimal near-field beam pair based on the result of the second measurement operation above; A step of determining the final beam pair among the optimal far-field beam pair and the optimal near-field beam pair; and A method comprising the step of communicating with the base station based on the final beam pair. UE's method.

2. In Claim 1, The first measurement operation is performed on a signal transmitted through the far-field beam sweeping of the base station, and the second measurement operation is performed on a signal transmitted through the near-field beam sweeping of the base station. UE's method.

3. In Claim 1, The optimal far-field beam pair is a beam pair having an RSRP (reference signal received power) greater than or equal to the far-field RSRP threshold among all beam pairs between the UE and the base station, and the one or more near-field beam pairs are beam pairs having an RSRP less than the far-field RSRP threshold and greater than or equal to the near-field RSRP threshold among all beam pairs, and the optimal near-field beam pair is a beam pair having the largest RSRP among the one or more near-field beam pairs. UE's method.

4. In Claim 1, The method further includes the step of transmitting to the base station a UE capability response including the ability to report the result of the first measurement operation, The reporting method for the result of the first measurement operation is determined based on the reporting capability, UE's method.

5. In Claim 4, The method further includes the step of receiving a UE capability request from the base station, The above UE capability response is transmitted as a response to the above UE capability request, UE's method.

6. In Claim 1, The method further includes the step of transmitting the result of the first measurement operation to the base station, The above one or more near-field beam pairs are determined at the base station based on the result of the first measurement operation, UE's method.

7. In Claim 1, The step of performing the above second measurement operation is, A step of determining one or more near-field beam pairs by applying a beam pair determination criterion received from the base station to the result of the first measurement operation; and A step comprising performing the second measurement operation for the above one or more near-field beam pairs, UE's method.

8. In Claim 1, The above configuration information includes beam management information, and a type field included in the beam management information indicates the type of beam management procedure performed between the UE and the base station, and the type of beam management procedure is classified into far-field beam management procedure, near-field beam management procedure, and hybrid-field beam management procedure, and the hybrid-field beam management procedure includes the far-field beam management procedure and the near-field beam management procedure. UE's method.

9. In Claim 1, The above configuration information includes reporting information, and the reporting information includes at least one of information indicating a reporting method, information indicating a reporting target, or an RSRP threshold, and the reporting method is classified as an individual reporting method or a map reporting method, and the reporting target is one or more beams, UE's method.

10. In Claim 1, The above setting information includes reporting format information of an RSRP map including the result of the first measurement operation, and the reporting format information includes at least one of a base station-UE beam index, a performance metric, splitting information, or a reporting type, and the splitting information indicates whether the RSRP map is split transmission, and the reporting type indicates periodic reporting or event-triggered reporting of the RSRP map. UE's method.

11. In Claim 1, The above setting information includes a beam pair determination criterion, and the beam pair determination criterion includes at least one of a far-field RSRP threshold, a near-field RSRP threshold, a maximum number of determinable beam pairs, or a timer indicating the time for which the beam pair determination procedure is performed. UE's method.

12. As a method of base station, A step of transmitting configuration information for a beam management procedure to the UE (user equipment); A step of transmitting a signal to the UE by performing far-field beam sweeping; A step of determining an optimal far-field beam pair based on a first measurement result for the signal transmitted through the far-field beam sweeping; A step of transmitting a signal to the UE by performing near-field beam sweeping for measuring one or more near-field beam pairs determined based on the first measurement result; A step of determining an optimal near-field beam pair based on a second measurement result for the signal transmitted through the above near-field beam sweeping; A step of determining the final beam pair among the optimal far-field beam pair and the optimal near-field beam pair; and A method comprising the step of communicating with the UE based on the above final beam pair, Base station method.

13. In Claim 12, The optimal far-field beam pair is a beam pair having an RSRP (reference signal received power) greater than or equal to the far-field RSRP threshold among all beam pairs between the UE and the base station, and the one or more near-field beam pairs are beam pairs having an RSRP less than the far-field RSRP threshold and greater than or equal to the near-field RSRP threshold among all beam pairs, and the optimal near-field beam pair is a beam pair having the largest RSRP among the one or more near-field beam pairs. Base station method.

14. In Claim 12, The method further includes the step of receiving a UE capability response from the UE, which includes the capability to report the first measurement result. The reporting method for the above first measurement result is determined based on the above reporting capability, Base station method.

15. In Claim 12, The step of receiving the first measurement result from the UE; and The method further comprises the step of determining one or more near-field beam pairs based on the first measurement result. Base station method.

16. In Claim 12, The method further comprises the step of receiving from the UE information of one or more near-field beam pairs determined in the UE based on the first measurement result. Base station method.

17. In Claim 12, The above configuration information includes beam management information, and a type field included in the beam management information indicates the type of beam management procedure performed between the UE and the base station, and the type of beam management procedure is classified into far-field beam management procedure, near-field beam management procedure, and hybrid-field beam management procedure, and the hybrid-field beam management procedure includes the far-field beam management procedure and the near-field beam management procedure. Base station method.

18. In Claim 12, The above configuration information includes reporting information, and the reporting information includes at least one of information indicating a reporting method, information indicating a reporting target, or an RSRP threshold, and the reporting method is classified as an individual reporting method or a map reporting method, and the reporting target is one or more beams, Base station method.

19. In Claim 12, The above configuration information includes reporting format information of an RSRP map including the first measurement result, and the reporting format information includes at least one of a base station-UE beam index, a performance metric, splitting information, or a reporting type, the splitting information indicates whether the RSRP map is split transmission, and the reporting type indicates periodic reporting or event-triggered reporting of the RSRP map. Base station method.

20. In Claim 12, The above setting information includes a beam pair determination criterion, and the beam pair determination criterion includes at least one of a far-field RSRP threshold, a near-field RSRP threshold, a maximum number of determinable beam pairs, or a timer indicating the time for which the beam pair determination procedure is performed. Base station method.

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