Control terminal, network node, communication method, chipset, program, and mobile communication system

Abstract

To provide a device and a method for controlling a repeating device for extending coverage of a base station while suppressing interference, in a signal transmission on a high frequency band.SOLUTION: In a mobile communication system, an NCR-UE (control terminal), which controls an NCR device (repeating device) for repeating a radio signal between a gNB (base station) and UE (User equipment), receives setting information used by the NCR device to direct a beam to the UE from the gNB, and controls the NCR device so as to direct the beam to the UE based on the setting information.SELECTED DRAWING: Figure 14

Description

[Technical Field]

[0001] The present disclosure relates to a control terminal, a network node, a communication method, a chipset, a program, and a mobile communication system used in a mobile communication system. [Background technology]

[0002] In recent years, fifth-generation (5G) mobile communication systems have been attracting attention. NR (New Radio), the radio access technology of 5G systems, is capable of wideband transmission using higher frequency bands than LTE (Long Term Evolution), the fourth-generation radio access technology.

[0003] Radio signals (radio waves) in high frequency bands such as millimeter waves or terahertz waves have a tendency to propagate in a highly directional manner, which poses a problem of reducing the coverage of base stations. To solve this problem, repeater devices, which are a type of relay device that relays radio signals between base stations and user devices and can be controlled from a network, have attracted attention (see, for example, Non-Patent Document 1). Such repeater devices can expand the coverage of base stations while suppressing interference, for example, by amplifying radio signals received from base stations and transmitting them directionally. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] 3GPP contribution: RP-213700, “New SI: Study on NR Network-controlled Repeaters” Summary of the Invention

[0005] A control terminal according to a first aspect is a device for controlling a relay device that relays radio signals between a base station and a user device in a mobile communication system. The control terminal includes a receiver that receives, from the base station, configuration information used by the relay device to direct a beam toward the user device, and a controller that controls the relay device to direct the beam toward the user device based on the configuration information.

[0006] A base station according to a second aspect is a base station used in a mobile communication system having a control terminal that controls a relay device that relays radio signals between the base station and a user device, and includes a transmitter that transmits to the control terminal configuration information used by the relay device to direct a beam toward the user device.

[0007] A communication method according to a third aspect is a method executed by a control terminal that controls a relay device that relays radio signals between a base station and a user device in a mobile communication system, and includes the steps of receiving, from the base station, configuration information used by the relay device to direct a beam toward the user device, and controlling the relay device to direct the beam toward the user device based on the configuration information. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a diagram illustrating a configuration of a mobile communication system according to an embodiment. [Figure 2] FIG. 10 is a diagram showing the configuration of a protocol stack of a radio interface of a user plane that handles data. [Figure 3] FIG. 1 is a diagram showing the configuration of a protocol stack of a radio interface of a control plane that handles signaling (control signals). [Figure 4] FIG. 1 is a diagram illustrating an application scenario of an NCR device (relay device) according to an embodiment. [Figure 5] FIG. 1 is a diagram illustrating an application scenario of an NCR device according to an embodiment. [Figure 6]1 is a diagram illustrating an example of the configuration of a protocol stack in a mobile communication system having an NCR device and an NCR-UE (control terminal) according to an embodiment. [Figure 7] FIG. 2 is a diagram illustrating an example of the configuration of an NCR-UE and an NCR device according to an embodiment. [Figure 8] A diagram showing an example configuration of a gNB (base station) according to an embodiment. [Figure 9] A figure showing an example of downlink signaling from a gNB to an NCR-UE according to an embodiment. [Figure 10] FIG. 2 is a diagram illustrating an example of an NCR control signal according to the embodiment. [Figure 11] A figure showing an example of uplink signaling from an NCR-UE to a gNB according to an embodiment. [Figure 12] FIG. 10 is a diagram illustrating an example of NCR capability information according to the embodiment. [Figure 13] FIG. 2 is a diagram illustrating an example of an operation of the mobile communication system according to the embodiment. [Figure 14] FIG. 10 is a diagram for explaining beamforming control according to the embodiment. [Figure 15] FIG. 10 is a diagram illustrating an example of an operation flow of a first operation pattern of beamforming control according to the embodiment. [Figure 16] FIG. 10 is a diagram showing another example of the operation flow of the first operation pattern of the beamforming control according to the embodiment. [Figure 17] FIG. 10 is a diagram illustrating an example of an operation flow of a second operation pattern of beamforming control according to the embodiment. [Figure 18] FIG. 10 is a diagram for explaining a RIS device (relay device) according to another embodiment. [Figure 19] FIG. 10 is a diagram for explaining a RIS device according to another embodiment. [Figure 20] FIG. 10 is a diagram for explaining a RIS device according to another embodiment. [Figure 21] FIG. 10 is a diagram for explaining a RIS device according to another embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] When controlling relay devices such as repeater devices from a network, the control technology for specifically controlling the relay devices has not yet been established, and it is currently difficult to efficiently extend coverage using relay devices.

[0010] Therefore, an object of the present disclosure is to enable appropriate control of a relay device that relays transmission between a base station and a user device.

[0011] A mobile communication system according to an embodiment will be described with reference to the drawings. In the description of the drawings, the same or similar parts are denoted by the same or similar reference numerals.

[0012] (1) Configuration of mobile communication system FIG. 1 is a diagram showing the configuration of a mobile communication system according to an embodiment. The mobile communication system 1 conforms to the 5th Generation System (5GS) of the 3GPP (registered trademark) standard. In the following description, 5GS is used as an example, but the mobile communication system may also be at least partially based on an LTE (Long Term Evolution) system. Alternatively, the mobile communication system may also be at least partially based on a sixth generation (6G) system.

[0013] The mobile communication system 1 includes a user equipment (UE) 100, a 5G radio access network (NG-RAN) 10, and a 5G core network (5GC) 20. Hereinafter, the NG-RAN 10 may be simply referred to as the RAN 10. The 5GC 20 may be simply referred to as the core network (CN) 20.

[0014] The UE 100 is a mobile wireless communication device. The UE 100 may be any device that is used by a user. For example, the UE 100 may be a mobile phone terminal (including a smartphone), a tablet terminal, a laptop PC, a communication module (including a communication card or a chipset), a sensor or a device provided in a sensor, a vehicle or a device provided in a vehicle (Vehicle UE), or an aircraft or a device provided in an aircraft (Aerial UE).

[0015] The NG-RAN 10 includes a base station (called "gNB" in the 5G system) 200. The gNBs 200 are connected to each other via an Xn interface, which is an interface between base stations. The gNB 200 manages one or more cells. The gNB 200 performs wireless communication with a UE 100 that has established a connection with its own cell. The gNB 200 has a radio resource management (RRM) function, a routing function for user data (hereinafter simply referred to as "data"), a measurement control function for mobility control and scheduling, etc. The term "cell" is used to indicate the smallest unit of a wireless communication area. The term "cell" is also used to indicate a function or resource that performs wireless communication with a UE 100. One cell belongs to one carrier frequency (hereinafter simply referred to as "frequency").

[0016] In addition, gNBs can also connect to the Evolved Packet Core (EPC), which is the LTE core network. LTE base stations can also connect to 5GC. LTE base stations and gNBs can also be connected via a base station-to-base station interface.

[0017] The 5GC20 includes an Access and Mobility Management Function (AMF) and a User Plane Function (UPF) 300. The AMF performs various mobility controls for the UE 100. The AMF manages the mobility of the UE 100 by communicating with the UE 100 using NAS (Non-Access Stratum) signaling. The UPF controls data forwarding. The AMF and UPF are connected to the gNB 200 via an NG interface, which is an interface between a base station and a core network.

[0018] FIG. 2 is a diagram showing the configuration of a protocol stack of a radio interface of a user plane that handles data.

[0019] The user plane radio interface protocol includes a physical (PHY) layer, a medium access control (MAC) layer, a radio link control (RLC) layer, a packet data convergence protocol (PDCP) layer, and a service data adaptation protocol (SDAP) layer.

[0020] The PHY layer performs encoding / decoding, modulation / demodulation, antenna mapping / demapping, and resource mapping / demapping. Data and control information are transmitted between the PHY layer of UE100 and the PHY layer of gNB200 via a physical channel. The PHY layer of UE100 receives downlink control information (DCI) transmitted from gNB200 on a physical downlink control channel (PDCCH). Specifically, UE100 performs blind decoding of the PDCCH using a radio network temporary identifier (RNTI) and acquires successfully decoded DCI as DCI addressed to the UE. The DCI transmitted from gNB200 has CRC parity bits scrambled by the RNTI added.

[0021] The MAC layer performs data priority control, retransmission processing using Hybrid Automatic Repeat reQuest (HARQ), random access procedures, etc. Data and control information are transmitted between the MAC layer of UE100 and the MAC layer of gNB200 via transport channels. The MAC layer of gNB200 includes a scheduler, which determines the uplink and downlink transport format (transport block size, modulation and coding scheme (MCS)) and the resource blocks to be allocated to UE100.

[0022] The RLC layer transmits data to the RLC layer on the receiving side using the functions of the MAC layer and PHY layer. Data and control information are transmitted between the RLC layer of the UE 100 and the RLC layer of the gNB 200 via logical channels.

[0023] The PDCP layer performs header compression / decompression, encryption / decryption, etc.

[0024] The SDAP layer maps IP flows, which are the units for Quality of Service (QoS) control by the core network, to radio bearers, which are the units for QoS control by the Access Stratum (AS). Note that if the RAN is connected to the EPC, SDAP is not necessary.

[0025] FIG. 3 is a diagram showing the configuration of a protocol stack of a radio interface of a control plane that handles signaling (control signals).

[0026] The protocol stack of the radio interface of the control plane has a Radio Resource Control (RRC) layer and a Non-Access Stratum (NAS) layer instead of the SDAP layer shown in FIG.

[0027] RRC signaling for various settings is transmitted between the RRC layer of UE100 and the RRC layer of gNB200. The RRC layer controls logical channels, transport channels, and physical channels according to the establishment, re-establishment, and release of radio bearers. When there is a connection (RRC connection) between the RRC of UE100 and the RRC of gNB200, UE100 is in an RRC connected state. When there is no connection (RRC connection) between the RRC of UE100 and the RRC of gNB200, UE100 is in an RRC idle state. When the connection between the RRC of UE100 and the RRC of gNB200 is suspended, UE100 is in an RRC inactive state.

[0028] The NAS layer, which is located above the RRC layer, performs session management, mobility management, etc. NAS signaling is transmitted between the NAS layer of the UE 100 and the NAS layer of the AMF 300A. Note that the UE 100 has an application layer and the like in addition to the radio interface protocol. Also, the layer below the NAS layer is called the AS layer.

[0029] (2) Application scenarios for relay devices Next, an application scenario of the NCR device, which is a relay device according to the embodiment, will be described. Figures 4 and 5 are diagrams showing application scenarios of the NCR device according to the embodiment.

[0030] 5G / NR enables broadband transmission using higher frequency bands than 4G / LTE. Radio signals in high frequency bands such as the millimeter wave band or terahertz wave band have high line-of-sight properties, which poses a challenge in reducing the coverage of the gNB 200. In FIG. 4, the UE 100A may be located outside the coverage area of ​​the gNB 200, for example, outside an area where a radio signal can be received directly from the gNB 200. There may be an obstruction between the gNB 200 and the UE 100A, preventing the UE 100A from communicating with the gNB 200 within line-of-sight.

[0031] In the embodiment, a repeater device (500A), which is a type of relay device that relays radio signals between a gNB 200 and a UE 100A and can be controlled from a network, is introduced into the mobile communication system 1. Hereinafter, such a repeater device is referred to as an NCR (Network-Controlled Repeater) device. Such a repeater device may also be referred to as a smart repeater device.

[0032] For example, the NCR device 500A amplifies a radio signal (wireless signal) received from the gNB 200 and transmits the signal by directional transmission. Specifically, the NCR device 500A receives a radio signal transmitted by the gNB 200 by beamforming. Then, the NCR device 500A amplifies the received radio signal and transmits the amplified radio signal by directional transmission. Here, the NCR device 500A may transmit the radio signal with fixed directivity. Alternatively, the NCR device 500A may transmit the radio signal by a variable (adaptive) directional beam. This enables efficient expansion of the coverage of the gNB 200. In the embodiment, it is mainly assumed that the NCR device 500A is applied to downlink communication from the gNB 200 to the UE 100A, but the NCR device 500A can also be applied to uplink communication from the UE 100A to the gNB 200.

[0033] Also, as shown in FIG. 5, a new UE (hereinafter referred to as "NCR-UE") 100B, which is a type of control terminal for controlling the NCR device 500A, is introduced. The NCR-UE 100B establishes a wireless connection with the gNB 200 and performs wireless communication with the gNB 200, thereby controlling the NCR device 500A in cooperation with the gNB 200. This enables efficient coverage expansion using the NCR device 500A. The NCR-UE 100B controls the NCR device 500A under control from the gNB 200.

[0034] The NCR-UE 100B may be configured separately from the NCR device 500A. For example, the NCR-UE 100B may be located near the NCR device 500A and electrically connected to the NCR device 500A. The NCR-UE 100B may be connected to the NCR device 500A by wire or wirelessly. Alternatively, the NCR-UE 100B may be configured integrally with the NCR device 500A. The NCR-UE 100B and the NCR device 500A may be fixedly installed, for example, at the coverage edge (cell edge) of the base station 200 or on a wall or window of a building. The NCR-UE 100B and the NCR device 500A may be mobile, installed in a vehicle, for example. Furthermore, one NCR-UE 100B may control multiple NCR devices 500A.

[0035] In the example shown in FIG. 5, the NCR device 500A dynamically or quasi-statically changes a beam to be transmitted or received. For example, the NCR device 500A forms a beam toward each of the UE 100A1 and the UE 100A2. The NCR device 500A may also form a beam toward the gNB 200. For example, in a communication resource between the gNB 200 and the UE 100A1, the NCR device 500A transmits a radio signal received from the gNB 200 toward the UE 100A1 by beamforming and / or transmits a radio signal received from the UE 100A1 by beamforming toward the gNB 200. In a communication resource between the gNB 200 and the UE 100A2, the NCR device 500A transmits a radio signal received from the gNB 200 toward the UE 100A2 by beamforming and / or transmits a radio signal received from the UE 100A2 by beamforming toward the gNB 200. Instead of or in addition to forming a beam, the NCR device 500A may form a null (so-called null steering) toward a non-communicating UE 100 (not shown) and / or a neighboring gNB 200 (not shown) for interference suppression. Hereinafter, beam (beam forming) may be read as null (null steering). Alternatively, beam (beam forming) may be read as beam and null (beam forming and null steering).

[0036] FIG. 6 is a diagram showing an example of the configuration of a protocol stack in a mobile communication system 1 having an NCR device 500A and an NCR-UE 100B according to the embodiment.

[0037] 6, the NCR device 500A relays radio signals transmitted and received between the gNB 200 and the UE 100A. The NCR device 500A has an RF (Radio Frequency) function for amplifying and relaying received radio signals, and performs directional transmission using beamforming (for example, analog beamforming).

[0038] The NCR-UE 100B has at least one layer (entity) of PHY, MAC, RRC, and F1-AP (Application Protocol). The F1-AP is a type of fronthaul interface. The NCR-UE 100B exchanges downlink signaling and / or uplink signaling (described below) with the gNB 200 via at least one of PHY, MAC, RRC, and F1-AP. If the NCR-UE 100B is a type or part of a base station, the NCR-UE 100B may exchange with the gNB 200 via an Xn AP (Xn-AP), which is an inter-base station interface.

[0039] (3) Example of the configuration of the control terminal and relay device Next, the configurations of the NCR-UE 100B (control terminal) and the NCR device 500A (relay device) according to the embodiment will be described. Fig. 7 is a diagram showing an example of the configuration of the NCR-UE 100B and the NCR device 500A according to the embodiment.

[0040] As shown in FIG. 7, NCR-UE 100B includes a receiving unit 110, a transmitting unit 120, a control unit 130, and an interface 140.

[0041] The receiving unit 110 performs various receptions under the control of the control unit 130. The receiving unit 110 includes an antenna and a receiver. The receiver converts a radio signal (wireless signal) received by the antenna into a baseband signal (received signal) and outputs it to the control unit 130. The transmitting unit 120 performs various transmissions under the control of the control unit 130. The transmitting unit 120 includes an antenna and a transmitter. The transmitter converts a baseband signal (transmitted signal) output by the control unit 130 into a radio signal and transmits it from the antenna.

[0042] The control unit 130 performs various controls in the NCR-UE 100B. The control unit 130 includes at least one processor and at least one memory. The memory stores programs executed by the processor and information used in processing by the processor. The processor may include a baseband processor and a CPU (Central Processing Unit). The baseband processor performs modulation / demodulation and encoding / decoding of baseband signals. The CPU executes programs stored in the memory to perform various processes. The control unit 130 also performs functions of at least one layer of PHY, MAC, RRC, and F1-AP.

[0043] The interface 140 is electrically connected to the NCR device 500A. The control unit 130 controls the NCR device 500A via the interface 140. When the NCR-UE 100B and the NCR device 500A are integrally configured, the NCR-UE 100B does not need to have the interface 140. Furthermore, the receiving unit 110 and the transmitting unit 120 of the NCR-UE 100B may be integrally configured with the wireless unit 510A of the NCR device 500A.

[0044] The NCR device 500A includes a radio unit 510A and an NCR control unit 520A. The radio unit 510A includes an antenna unit 510a including multiple antennas, an RF circuit 510b including an amplifier, and a directivity control unit 510c that controls the directivity of the antenna unit 510a. The RF circuit 510b amplifies and relays (transmits) radio signals transmitted and received by the antenna unit 510a. The RF circuit 510b may convert analog radio signals into digital signals and then reconvert them to analog signals after digital signal processing. The directivity control unit 510c may perform analog beamforming using analog signal processing, digital beamforming using digital signal processing, or hybrid analog and digital beamforming.

[0045] The NCR control unit 520A controls the wireless unit 510A in response to a control signal from the control unit 130 of the NCR-UE 100B. The NCR control unit 520A may include at least one processor. The NCR control unit 520A may output information related to the capabilities of the NCR device 500A to the NCR-UE 100B. When the NCR-UE 100B and the NCR device 500A are configured integrally, the control unit 130 of the NCR-UE 100B and the NCR control unit 520A of the NCR device 500A may also be configured integrally.

[0046] In the embodiment, the receiver 110 of the NCR-UE 100B receives signaling (downlink signaling) used to control the NCR device 500A from the gNB 200 via wireless communication. The controller 130 of the NCR-UE 100B controls the NCR device 500A based on the signaling. This enables the gNB 200 to control the NCR device 500A via the NCR-UE 100B.

[0047] In the embodiment, the control unit 130 of the NCR-UE 100B controls the NCR device 500A. The control unit 130 of the NCR-UE 100B acquires NCR capability information indicating the capability of the NCR device 500A from the NCR device 500A (NCR control unit 520A). Then, the transmission unit 120 of the NCR-UE 100B transmits the acquired NCR capability information to the gNB 200 by wireless communication. The NCR capability information is an example of uplink signaling from the NCR-UE 100B to the gNB 200. This enables the gNB 200 to grasp the capability of the NCR device 500A.

[0048] (4) Example of base station configuration Next, a configuration of the gNB 200 (base station) according to the embodiment will be described. Fig. 8 is a diagram illustrating an example of the configuration of the gNB 200 according to the embodiment.

[0049] As shown in FIG. 8, the gNB 200 includes a transmitter 210, a receiver 220, a controller 230, and a backhaul communication unit 240.

[0050] The transmitting unit 210 performs various transmissions under the control of the control unit 230. The transmitting unit 210 includes an antenna and a transmitter. The transmitter converts a baseband signal (transmission signal) output by the control unit 230 into a radio signal and transmits it from the antenna. The receiving unit 220 performs various receptions under the control of the control unit 230. The receiving unit 220 includes an antenna and a receiver. The receiver converts a radio signal received by the antenna into a baseband signal (reception signal) and outputs it to the control unit 230. The transmitting unit 210 and the receiving unit 220 may be capable of beamforming using multiple antennas.

[0051] The control unit 230 performs various controls in the gNB 200. The control unit 230 includes at least one processor and at least one memory. The memory stores programs executed by the processor and information used in processing by the processor. The processor may include a baseband processor and a CPU. The baseband processor performs modulation / demodulation and encoding / decoding of baseband signals. The CPU executes programs stored in the memory to perform various processes.

[0052] The backhaul communication unit 240 is connected to neighboring base stations via an inter-base station interface. The backhaul communication unit 240 is connected to the AMF / UPF 300 via a base station-core network interface. Note that the gNB is composed of a CU (Central Unit) and a DU (Distributed Unit) (i.e., functionally divided), and both units may be connected via an F1 interface.

[0053] In the embodiment, the transmitter 210 of the gNB 200 transmits, via wireless communication, signaling (downlink signaling) used to control the NCR device 500A to the NCR-UE 100B that controls the NCR device 500A. This enables the gNB 200 to control the NCR device 500A via the NCR-UE 100B.

[0054] In an embodiment, the receiver 220 of the gNB 200 receives, via wireless communication, NCR capability information indicating the capability of the NCR device 500A from the NCR-UE 100B that controls the NCR device 500A. The NCR capability information is an example of uplink signaling from the NCR-UE 100B to the gNB 200. This allows the gNB 200 to grasp the capability of the NCR device 500A.

[0055] (5) Example of operation scenario Next, an example of an operation scenario of the mobile communication system 1 according to the embodiment will be described.

[0056] (5.1) Example of Downlink Signaling FIG. 9 is a diagram showing an example of downlink signaling from the gNB 200 to the NCR-UE 100B according to the embodiment.

[0057] The gNB200 (transmitter 210) transmits downlink signaling to the NCR-UE100B. The downlink signaling may be an RRC message, which is signaling of the RRC layer (i.e., Layer 3). The downlink signaling may be a MAC CE (Control Element), which is signaling of the MAC layer (i.e., Layer 2). The downlink signaling may be downlink control information (DCI), which is signaling of the PHY layer (i.e., Layer 1). The downlink signaling may be UE-specific signaling or broadcast signaling. The downlink signaling may be a fronthaul message (e.g., an F1-AP message). If the NCR-UE100B is a type or part of a base station, the NCR-UE100B may communicate with the gNB200 via an Xn AP (Xn-AP), which is an inter-base station interface.

[0058] For example, as shown in FIG. 9 , the gNB 200 (transmitter 210) transmits an NCR control signal specifying the operation state of the NCR device 500A to the NCR-UE 100B that has established a wireless connection with the gNB 200 (step S1). In the following embodiment, an example will be mainly described in which the NCR control signal specifying the operation state of the NCR device 500A is MAC CE, which is signaling of the MAC layer (layer 2), or DCI, which is signaling of the PHY layer (layer 1). However, the NCR control signal may be included in an RRC Reconfiguration message, which is a type of RRC message individual to a UE, and transmitted to the NCR-UE 100B. The downlink signaling may be a message of a layer higher than the RRC layer (for example, an NCR application). The downlink signaling may be a message of a layer higher than the RRC layer encapsulated in a message of a layer lower than the RRC layer and transmitted. The NCR-UE 100B (transmitter 120) may transmit, on the uplink, a response message in response to the downlink signaling from the gNB 200. The response message may be transmitted in response to the NCR device 500A completing the configuration specified in the downlink signaling or receiving the configuration.

[0059] As shown in Fig. 10, the NCR control signal may include frequency control information that specifies the center frequency of a radio signal (e.g., a component carrier) to be relayed by the NCR device 500A. When the NCR control signal received from the gNB 200 includes frequency control information, the NCR-UE 100B (control unit 130) controls the NCR device 500A to relay a radio signal having a center frequency indicated by the frequency control information (step S2). The NCR control signal may include multiple pieces of frequency control information that specify different center frequencies. By including frequency control information in the NCR control signal, the gNB 200 can specify, via the NCR-UE 100B, the center frequency of a radio signal to be relayed by the NCR device 500A.

[0060] The NCR control signal may include mode control information that specifies an operation mode of the NCR device 500A. The mode control information may be associated with frequency control information (center frequency). The operation mode may be any of a mode in which the NCR device 500A performs omnidirectional transmission and / or reception, a mode in which the NCR device 500A performs fixed-directivity transmission and / or reception, a mode in which the NCR device 500A performs transmission and / or reception using a variable directional beam, and a mode in which the NCR device 500A performs MIMO (Multiple Input Multiple Output) relay transmission. The operation mode may be any of a beamforming mode (i.e., a mode that prioritizes improving a desired wave) and a null steering mode (i.e., a mode that prioritizes suppressing interference waves). When the NCR control signal received from the gNB 200 includes mode control information, the NCR-UE 100B (control unit 130) controls the NCR device 500A to operate in the operation mode indicated by the mode control information (step S2). Since the NCR control signal includes mode control information, the gNB200 can specify the operating mode of the NCR device 500A via the NCR-UE100B.

[0061] Here, the mode in which the NCR device 500A performs non-directional transmission and / or reception is a mode in which the NCR device 500A performs relay in all directions, and may be referred to as an omni-mode.

[0062] The mode in which the NCR device 500A performs fixed directional transmission and / or reception may be a directional mode realized by one directional antenna. Alternatively, the mode may be a beamforming mode realized by applying fixed phase and amplitude control (antenna weight control) to multiple antennas. Either of these modes may be specified (set) by the gNB 200 to the NCR-UE 100B.

[0063] The mode in which the NCR device 500A transmits and / or receives using a variable directional beam may be a mode in which analog beamforming is performed, a mode in which digital beamforming is performed, or a mode in which hybrid beamforming is performed. The mode may also be a mode in which an adaptive beam specific to the UE 100A is formed. Any of these modes may be specified (set) by the gNB 200 to the NCR-UE 100B.

[0064] In addition, in an operation mode in which beamforming is performed, beam control information described below may be provided from gNB200 to NCR-UE100B.

[0065] The mode in which the NCR device 500A performs MIMO relay transmission may be a mode in which SU (Single-User) spatial multiplexing is performed, a mode in which MU (Multi-User) spatial multiplexing is performed, or a mode in which transmit diversity is performed. Any of these modes may be specified (set) by the gNB 200 to the NCR-UE 100B.

[0066] The operation modes may include a mode in which relay transmission by the NCR device 500A is turned on (activated) and a mode in which relay transmission by the NCR device 500A is turned off (deactivated). Either of these modes may be specified (set) by an NCR control signal from the gNB 200 to the NCR-UE 100B.

[0067] The NCR control signal may include beam control information that specifies the transmission direction, transmission weight, or beam pattern when the NCR device 500A performs directional transmission. The beam control information may be associated with frequency control information (center frequency). The beam control information may include a PMI (Precoding Matrix Indicator). When the NCR control signal received from the gNB 200 includes beam control information, the NCR-UE 100B (control unit 130) controls the NCR device 500A to form the transmission directivity (beam) indicated by the beam control information (step S2). When the NCR control signal includes beam control information, the gNB 200 can control the transmission directivity of the NCR device 500A via the NCR-UE 100B.

[0068] The NCR control signal may include output control information that specifies the degree to which the NCR device 500A amplifies a radio signal (amplification gain) or transmission power. The output control information may be information indicating a difference (i.e., a relative value) between a current amplification gain or transmission power and a target amplification gain or transmission power. When the NCR control signal received from the gNB 200 includes output control information, the NCR-UE 100B (control unit 130) controls the NCR device 500A to change the amplification gain or transmission power to the amplification gain or transmission power indicated by the output control information (step S2). The output control information may be associated with frequency control information (center frequency). The output control information may be information that specifies any one of the amplifier gain, beamforming gain, and antenna gain of the NCR device 500A. The output control information may be information that specifies the transmission power of the NCR device 500A.

[0069] When one NCR-UE 100B controls multiple NCR devices 500A, the gNB 200 (transmission unit 210) may transmit an NCR control signal to the NCR-UE 100B for each NCR device 500A. In this case, the NCR control signal may include an identifier (NCR identifier) ​​of the corresponding NCR device 500A. The NCR-UE 100B (control unit 130) that controls multiple NCR devices 500A determines the NCR device 500A to which the NCR control signal should be applied, based on the NCR identifier included in the NCR control signal received from the gNB 200. Note that the NCR identifier may be transmitted from the NCR-UE 100B to the gNB 200 together with the NCR control signal, even when the NCR-UE 100B controls only one NCR device 500A.

[0070] In this way, the NCR-UE 100B (control unit 130) controls the NCR device 500A based on the NCR control signal from the gNB 200. This enables the gNB 200 to control the NCR device 500A via the NCR-UE 100B.

[0071] (5.2) Example of uplink signaling FIG. 11 is a diagram showing an example of uplink signaling from the NCR-UE 100B to the gNB 200 according to the embodiment.

[0072] The NCR-UE 100B (transmitter 210) transmits uplink signaling to the gNB 200. The uplink signaling may be an RRC message, which is signaling of the RRC layer. The uplink signaling may be MAC CE, which is signaling of the MAC layer. The uplink signaling may be uplink control information (UCI), which is signaling of the PHY layer. The uplink signaling may be a fronthaul message (e.g., an F1-AP message) or an inter-base station message (e.g., an Xn-AP message). The uplink signaling may be a message of a layer higher than the RRC layer (e.g., an NCR application). The uplink signaling may be a message of a layer higher than the RRC layer encapsulated in a message of a layer lower than the RRC layer and transmitted. In addition, the gNB200 (transmitter 210) may transmit a response message in response to the uplink signaling from the NCR-UE100B on the downlink, and the NCR-UE100B (receiver 110) may receive the response message.

[0073] For example, the NCR-UE 100B (transmitter 120), which has established a wireless connection with the gNB 200, transmits NCR capability information indicating the capabilities of the NCR device 500A to the gNB 200 via wireless communication (step S5). The NCR-UE 100B (transmitter 120) may include the NCR capability information in a UE Capability message or a UE Assistant Information message, which are types of RRC messages, and transmit the message to the gNB 200. The NCR-UE 100B (transmitter 120) may transmit the NCR capability information (NCR capability information and / or operation state information) to the gNB 200 in response to a request or inquiry from the gNB 200.

[0074] As shown in FIG. 12, the NCR capability information may include supported frequency information indicating frequencies supported by the NCR device 500A. The supported frequency information may be a numerical value or an index indicating a center frequency of the frequencies supported by the NCR device 500A. Alternatively, the supported frequency information may be a numerical value or an index indicating a range of frequencies supported by the NCR device 500A. When the NCR capability information received from the NCR-UE 100B includes supported frequency information, the gNB 200 (control unit 230) can determine the frequencies supported by the NCR device 500A based on the supported frequency information. Then, the gNB 200 (control unit 230) may set the center frequency of the radio signal targeted by the NCR device 500A within the range of frequencies supported by the NCR device 500A.

[0075] The NCR capability information may include mode capability information related to operation modes that the NCR device 500A can support or switching between operation modes. As described above, the operation mode may be at least one of a mode in which the NCR device 500A performs omnidirectional transmission and / or reception, a mode in which the NCR device 500A performs fixed-directivity transmission and / or reception, a mode in which the NCR device 500A performs transmission and / or reception using a variable directional beam, and a mode in which the NCR device 500A performs MIMO (Multiple Input Multiple Output) relay transmission. The operation mode may be either a beamforming mode (i.e., a mode that prioritizes improving a desired wave) or a null steering mode (i.e., a mode that prioritizes suppressing interference waves). The mode capability information may be information indicating which of these operation modes the NCR device 500A can support. The mode capability information may also be information indicating which of these operation modes mode switching is possible between. When the NCR capability information received from the NCR-UE 100B includes mode capability information, the gNB 200 (control unit 230) can determine the operation mode and mode switching supported by the NCR device 500A based on the mode capability information. Then, the gNB 200 (control unit 230) may set the operation mode of the NCR device 500A within the range of the determined operation mode and mode switching.

[0076] The NCR capability information may include beam capability information indicating the beam variable range, beam variable resolution, or number of variable patterns when the NCR device 500A transmits and / or receives using a variable directional beam. The beam capability information may be, for example, information indicating the variable range of the beam angle based on the horizontal or vertical direction (e.g., controllable from 30° to 90°), or information indicating an absolute angle. The beam capability information may be expressed by the direction and / or elevation angle of the beam. The beam capability information may be information indicating the angle change per variable step (e.g., 5° / step horizontally, 10° / step vertically). Alternatively, the beam capability information may be information indicating the number of variable steps (e.g., 10 steps horizontally, 20 steps vertically). The beam capability information may be information indicating the number of variable beam patterns in the NCR device 500A (e.g., beam patterns 1 to 10, a total of 10 patterns). When the NCR capability information received from the NCR-UE 100B includes beam capability information, the gNB 200 (control unit 230) can determine the beam angle change or beam pattern that the NCR device 500A can support based on the beam capability information. The gNB 200 (control unit 230) may then set the beam of the NCR device 500A within the range of the determined beam angle change or beam pattern. The beam capability information may be null capability information. In the case of null capability information, the null capability information indicates the null control capability when null steering is performed.

[0077] The NCR capability information may include control delay information indicating a control delay time in the NCR device 500A. For example, the control delay information is information indicating a delay time (e.g., 1 ms, 10 ms, etc.) from the timing when the NCR-UE 100B receives an NCR control signal or the timing when the NCR-UE 100B transmits a setting completion notice for the NCR control signal to the gNB 200 until the control (change of operation mode or change of beam) according to the NCR control signal is completed. When the NCR capability information received from the NCR-UE 100B includes control delay information, the gNB 200 (control unit 230) can ascertain the control delay time in the NCR device 500A based on the control delay information.

[0078] The NCR capability information may include amplification characteristic information relating to the amplification characteristic or output power characteristic of a radio signal in the NCR device 500A. The amplification characteristic information may be information indicating the amplifier gain (dB), beamforming gain (dB), or antenna gain (dBi) of the NCR device 500A. The amplification characteristic information may be information indicating the amplification variable range (e.g., 0 dB to 60 dB) of the NCR device 500A. The amplification characteristic information may be information indicating the number of steps (e.g., 10 steps) of the gain that the NCR device 500A can change, or the amplification per variable step (e.g., 10 dB / step). The amplification characteristic information may be information indicating the variable range (e.g., 0 dBm to 30 dBm) of the output power of the NCR device 500A. The amplification characteristic information may be information indicating the number of steps (e.g., 10 steps) of the output power that the NCR device 500A can change, or the output power per variable step (e.g., 10 dBm / step).

[0079] The NCR capability information may include location information indicating the installation location of the NCR device 500A. The location information may include one or more of latitude, longitude, and altitude. The location information may include information indicating the distance and / or installation angle of the NCR device 500A relative to the gNB 200. The installation angle may be a relative angle with respect to the gNB 200, or may be a relative angle based on, for example, north, vertical, or horizontal. The installation location may be location information of the location where the antenna unit 510a of the NCR device 500A is installed.

[0080] The NCR capability information may include antenna information indicating the number of antennas the NCR device 500A has. The antenna information may be information indicating the number of antenna ports the NCR device 500A has. The antenna information may be information indicating the degrees of freedom of directivity control (beam or null formation). The degrees of freedom indicate how many beams can be formed (controlled) and are usually "(number of antennas) - 1". For example, in the case of two antennas, the degrees of freedom are 1. In the case of two antennas, a beam pattern resembling a figure eight is formed, but the degrees of freedom are 1 because directivity control is possible in only one direction.

[0081] When the NCR-UE 100B controls multiple NCR devices 500A, the NCR-UE 100B (transmission unit 120) may transmit NCR capability information to the gNB 200 for each NCR device 500A. In this case, the NCR capability information may include an identifier (NCR identifier) ​​of the corresponding NCR device 500A. Furthermore, when the NCR-UE 100B controls multiple NCR devices 500A, the NCR-UE 100B (transmission unit 120) may transmit information indicating at least one of the identifiers of the multiple NCR devices 500A and the number of the multiple NCR devices 500A. Note that the NCR identifier may be transmitted from the NCR-UE 100B to the gNB 200 together with the NCR capability information, even when the NCR-UE 100B controls only one NCR device 500A.

[0082] (5.3) Overall operation example FIG. 13 is a diagram showing an example of the operation of the mobile communication system 1 according to the embodiment.

[0083] In step S11, the NCR-UE 100B is in an RRC idle state or an RRC inactive state.

[0084] In step S12, the gNB200 (transmitter 210) broadcasts NCR support information indicating that the gNB200 supports the NCR-UE100B. For example, the gNB200 (transmitter 210) broadcasts a system information block (SIB) including the NCR support information. The NCR support information may be information indicating that the NCR-UE100B is accessible. Alternatively, the gNB200 (transmitter 210) may broadcast NCR non-support information indicating that the gNB200 does not support the NCR-UE100B. The NCR non-support information may be information indicating that the NCR-UE100B is not accessible.

[0085] An NCR-UE 100B (control unit 130) that has not established a wireless connection with a gNB 200 may determine, in response to receiving NCR support information from the gNB 200, that access to the gNB 200 is permitted, and may perform an access operation to establish a wireless connection with the gNB 200. The NCR-UE 100B (control unit 130) may perform cell reselection by regarding the gNB 200 (cell) to which access is permitted as having the highest priority.

[0086] On the other hand, if the gNB 200 does not broadcast NCR support information (or broadcasts NCR non-support information), the NCR-UE 100B (control unit 130) that has not established a wireless connection with the gNB 200 may determine that it is unable to access (establish a connection with) the gNB 200. This allows the NCR-UE 100B to establish a wireless connection only with a gNB 200 that can handle the NCR-UE 100B.

[0087] Note that, when the gNB 200 is congested, the gNB 200 may broadcast access restriction information that restricts access from the UE 100. However, unlike a normal UE 100, the NCR-UE 100B can be considered a network-side entity. Therefore, the NCR-UE 100B may ignore the access restriction information from the gNB 200. For example, when the NCR-UE 100B (control unit 130) receives NCR support information from the gNB 200, it may perform an operation to establish a wireless connection with the gNB 200 even if the gNB 200 is broadcasting access restriction information. For example, the NCR-UE 100B (control unit 130) may not execute (or may ignore) UAC (Unified Access Control). Alternatively, a special value indicating that the access is from an NCR-UE may be used as either or both of AC / AI (Access Category / Access Identity) used in UAC.

[0088] In step S13, the NCR-UE 100B (control unit 130) starts a random access procedure for the gNB 200. In the random access procedure, the NCR-UE 100B (transmitting unit 120) transmits a random access preamble (Msg1) and an RRC message (Msg3) to the gNB 200. Also, in the random access procedure, the NCR-UE 100B (receiving unit 110) receives a random access response (Msg2) and an RRC message (Msg4) from the gNB 200.

[0089] In step S14, when establishing a wireless connection with the gNB200, the NCR-UE100B (transmitting unit 120) may transmit NCR-UE information indicating that its own UE is an NCR-UE to the gNB200. For example, during a random access procedure with the gNB200, the NCR-UE100B (transmitting unit 120) transmits to the gNB200 the NCR-UE information included in a message for the random access procedure (e.g., Msg1, Msg3, Msg5). The gNB200 (control unit 230) recognizes that the accessing UE100 is the NCR-UE100B based on the NCR-UE information received from the NCR-UE100B, and can, for example, exclude the NCR-UE100B from the access restriction targets (i.e., accept the access).

[0090] In step S15, the NCR-UE 100B transitions from the RRC idle state or the RRC inactive state to the RRC connected state.

[0091] In step S16, the gNB 200 (transmitter 210) transmits a capability inquiry message to the NCR-UE 100B to inquire about the capability of the NCR-UE 100B. The NCR-UE 100B (receiver 110) receives the capability inquiry message.

[0092] In step S17, the NCR-UE 100B (transmitter 120) transmits a capability information message including the above-mentioned NCR capability information to the gNB 200. The gNB 200 (receiver 220) receives the capability information message. The gNB 200 (controller 230) determines the capability of the NCR device 500A based on the received capability information message.

[0093] In step S18, the gNB 200 (transmitter 210) transmits an NCR control signal specifying the operation state of the NCR device 500A to the NCR-UE 100B. The gNB 200 (transmitter 120) may transmit MAC CE, which is signaling of the MAC layer (layer 2), or DCI, which is signaling of the PHY layer (layer 1), to the NCR-UE 100B as the NCR control signal. The NCR-UE 100B (receiver 110) receives the NCR control signal.

[0094] In step S19, the NCR-UE 100B (control unit 130) controls the NCR device 500A based on the NCR control signal received from the gNB 200. The NCR-UE 100B (control unit 130) may control the NCR device 500A by notifying the NCR control signal received from the gNB 200 to the NCR device 500A (NCR control unit 520A).

[0095] In step S20, when the control (setting change) of the NCR device 500A is completed, the NCR-UE 100B (transmitter 120) may transmit a completion message to the gNB 200. Here, the NCR-UE 100B (controller 130) may determine the completion of the control based on a notification (feedback) from the NCR device 500A (NCR controller 520A). The gNB 200 (receiver 220) receives the completion message.

[0096] (6) Overview of beamforming control between relay device and user device Next, an overview of beamforming control between the relay device and the user device according to the embodiment will be described.

[0097] (6.1) In a mobile communication system (mobile communication system 1), a control terminal (NCR-UE100B) that controls a relay device (NCR device 500A) that relays radio signals between a base station (gNB200) and a user equipment (UE100A) has a receiver (receiver 110) that receives setting information from the base station used by the relay device to direct a beam toward the user equipment, and a control unit (control unit 130) that controls the relay device to direct the beam toward the user equipment based on the setting information.

[0098] Such configuration information is another example of the above-mentioned downlink signaling. The configuration information may be information included in the above-mentioned downlink signaling. Note that, as will be described in detail later, the relay device is not limited to an NCR device and may be a RIS (Reconfigurable Intelligent Surface) device. Furthermore, the control terminal is not limited to an NCR-UE and may be a RIS-UE. In the following embodiment, an example in which the relay device is an NCR device and the control terminal is an NCR-UE will be mainly described.

[0099] (6.2) In the above (6.1), the setting information may include resource setting information indicating resources required for the control terminal to receive an uplink signal from the user equipment, the receiving unit may receive the uplink signal from the user equipment using the resources indicated by the resource setting information, and the control unit may control the relay device to direct the beam toward the user equipment according to the received uplink signal.

[0100] (6.3) In the above (6.2), the control unit may use the received uplink signal to estimate the channel condition between the control terminal and the user equipment, and control the relay device to direct the beam toward the user equipment according to the estimated channel condition.

[0101] (6.4) In the above (6.2), the uplink signal may include beam control information, and the control unit may acquire the beam control information included in the received uplink signal and control the relay device to direct the beam toward the user device according to the acquired beam control information.

[0102] (6.5) In any one of the above (6.2) to (6.4), the receiving unit may receive an RRC (Radio Resource Control) message including the resource configuration information from the base station.

[0103] (6.6) In any of the above (6.2) to (6.5), the resource configuration information may include at least one of PUCCH configuration information indicating a PUCCH (Physical Uplink Control Channel) configuration of the user equipment, PUSCH configuration information indicating a PUSCH (Physical Uplink Shared Channel) configuration of the user equipment, SRS configuration information indicating an SRS (Sounding Reference Signal) configuration of the user equipment, and a C-RNTI (Cell Radio Network Temporary Identifier) ​​assigned to the user equipment.

[0104] (6.7) In the above (6.1), the setting information may include mode setting information for switching a control mode for beamforming among a plurality of control modes, and the control unit may control the relay device to direct the beam toward the user device using the control mode set in accordance with the mode setting information.

[0105] (6.8) In the above (6.7), the plurality of control modes may include a base station control mode in which the control terminal controls the relay device according to control from the base station.

[0106] (6.9) In the above (6.7) or (6.8), the plurality of control modes may include an autonomous control mode in which the control terminal autonomously controls the relay device without control from the base station.

[0107] (6.10) In any of the above (6.7) to (6.9), the plurality of control modes may further include a hybrid control mode that uses both control from the base station and autonomous control of the control terminal.

[0108] (6.11) In any one of the above (6.7) to (6.10), the plurality of control modes may further include a beam sweeping control mode for sequentially switching the beam direction of the relay device.

[0109] (6.12) In any of the above (6.7) to (6.11), the receiving unit may receive from the base station an RRC (Radio Resource Control) message including the mode setting information, a MAC (Medium Access Control) CE (Control Element) including the mode setting information, or a DCI (Downlink Control Information) including the mode setting information.

[0110] (6.13) In any of (6.7) to (6.12) above, the mode setting information may include information for switching between the control mode of the beamforming of the relay device, the control mode of timing switching of the relay device, and the control mode of on / off control of the relay device.

[0111] (6.14) In any of the above (6.7) to (6.13), the mode setting information may include information specifying timing for switching the control information.

[0112] (6.15) A base station used in a mobile communication system (mobile communication system 1) having a control terminal (NCR-UE100B) that controls a relay device (NCR device 500A) that relays radio signals between a base station (gNB200) and a user equipment (UE100A) includes a transmitter (transmitter 210) that transmits to the control terminal configuration information used by the relay device to direct a beam toward the user equipment.

[0113] (6.16) A communication method executed by a control terminal (NCR-UE100B) that controls a relay device (NCR device 500A) that relays radio signals between a base station (gNB200) and a user equipment (UE100A) in a mobile communication system (mobile communication system 1) includes the steps of receiving, from the base station, configuration information used by the relay device to direct a beam toward the user equipment, and controlling the relay device to direct the beam toward the user equipment based on the configuration information.

[0114] (7) Example of Beamforming Operation Between Relay Device and User Device Next, an example of an operation regarding beamforming between the relay device and the user device according to the embodiment will be described with reference to FIG.

[0115] As shown in Fig. 14, the NCR device 500A relays radio signals (referred to as "UE signals") between the gNB 200 and the UE 100A. The UE signals include uplink signals (referred to as "UE-UL signals") transmitted from the UE 100A to the gNB 200 and downlink signals (referred to as "UE-DL signals") transmitted from the gNB 200 to the UE 100A. The NCR device 500A relays the UE-UL signals from the UE 100A to the gNB 200, and also relays the UE-DL signals from the gNB 200 to the UE 100A.

[0116] The NCR-UE 100B transmits and receives radio signals (herein referred to as "NCR-UE signals") to and from the gNB 200. The NCR-UE signals include uplink signals (herein referred to as "NCR-UE-UL signals") transmitted from the NCR-UE 100B to the gNB 200, and downlink signals (herein referred to as "NCR-UE-DL signals") transmitted from the gNB 200 to the NCR-UE 100B. The NCR-UE-UL signals include the above-mentioned uplink signaling. The NCR-UE-DL signals include the above-mentioned downlink signaling.

[0117] The gNB 200 directs a beam toward the NCR-UE 100B based on the NCR-UE-UL signal from the NCR-UE 100B. Because the NCR device 500A is co-located with the NCR-UE 100B, when the gNB 200 directs a beam toward the NCR-UE 100B, the beam is ultimately directed toward both the NCR-UE 100B and the NCR device 500A. The gNB 200 transmits an NCR-UE-DL signal and a UE-DL signal using the beam. The NCR-UE 100B receives the NCR-UE-DL signal. Note that the NCR device 500A and the NCR-UE 100B may be at least partially integrated. For example, the NCR device 500A and the NCR-UE 100B may have integrated functions (e.g., antennas) for transmitting, receiving, or relaying UE signals and / or NCR-UE signals.

[0118] Here, the question arises as to how the NCR device 500A directs a beam toward the UE 100A. In the embodiment, the NCR-UE 100B receives, from the gNB 200, configuration information used by the NCR device 500A to direct a beam toward the UE 100A. The configuration information is downlink signaling included in the NCR-UE-DL signal. The NCR-UE 100B controls the NCR device 500A to direct a beam toward the UE 100A based on the configuration information. This makes it easier for the NCR device 500A to smoothly direct a beam toward the UE 100A. Below, first and second operation patterns related to such beamforming control will be described.

[0119] (7.1) First operation pattern In this first operation pattern, the setting information transmitted from the gNB 200 to the NCR-UE 100B includes resource setting information indicating resources necessary for the NCR-UE 100B to receive a UE-UL signal from the UE 100A. The NCR-UE 100B receives the UE-UL signal from the UE 100A using the resources indicated by the resource setting information, and controls the NCR device 500A to direct a beam toward the UE 100A in accordance with the received UE-UL signal.

[0120] For example, the NCR-UE 100B estimates the channel state between the NCR-UE 100B and the UE 100A using the received UE-UL signal. The NCR-UE 100B may estimate the channel state using a reference signal included in the UE-UL signal. The reference signal may be an SRS. Alternatively, the reference signal may be a demodulation reference signal (DMRS) included in the PUSCH (and PUCCH). The estimation of the channel state may include estimation of the direction of arrival and / or the distance of arrival of the UE-UL signal. The NCR-UE 100B controls the NCR device 500A to point a beam toward the UE 100A according to the estimated channel state.

[0121] The resource configuration information transmitted from gNB200 to NCR-UE100B may include at least one of PUCCH configuration information indicating the PUCCH configuration of UE100A, PUSCH configuration information indicating the PUSCH configuration of UE100A, SRS configuration information indicating the SRS configuration of UE100A, and a C-RNTI assigned to UE100A.

[0122] 15 is a diagram showing an example of an operation flow of this first operation pattern, in which non-essential steps are indicated by dashed lines.

[0123] In step S101, the gNB 200 establishes an RRC connection with the UE 100A and configures various resources (for example, PUCCH resources, PUSCH resources, SRS resources, and C-RNTI) of the UE 100A in the UE 100A. At this stage, relay transmission by the NCR device 500A may not be performed. Alternatively, the configuration of various resources from the gNB 200 to the UE 100A may not be performed at this stage, but may be performed in steps S108 to S109 described later.

[0124] In step S102, the NCR-UE 100B transmits a capability notification (NCR capability information) indicating that the NCR-UE 100B has uplink reception capability to the gNB 200. The gNB 200 receives the capability notification (NCR capability information).

[0125] In step S103, the gNB 200 transmits to the NCR-UE 100B a message including resource configuration information indicating resources required for the NCR-UE 100B to receive a UE-UL signal from the UE 100A. The NCR-UE 100B receives the message. The message may be a message similar to the downlink signaling described above. For example, the message may be RRC Reconfiguration, MAC CE, or DCI. The resource configuration information includes at least one information element selected from the following (A1) to (A4).

[0126] (A1) PUCCH settings The PUCCH configuration is an information element indicating the configuration of the PUCCH resource of the UE 100A. When the NCR-UE 100B acquires such a PUCCH configuration, the NCR-UE 100B becomes able to receive (and demodulate and decode) the PUCCH of the UE 100A. For example, the NCR-UE 100B uses a reference signal included in the PUCCH for channel estimation. The NCR-UE 100B may acquire beam control information (for example, a Precoding Matrix Indicator (PMI)) included in the PUCCH. An example of acquiring the beam control information will be described later.

[0127] (A2) PUSCH settings The PUSCH configuration is an information element indicating the configuration of the PUSCH resource of the UE 100A. When the NCR-UE 100B acquires such a PUSCH configuration, the NCR-UE 100B can receive (and demodulate and decode) the PUSCH of the UE 100A. For example, the NCR-UE 100B uses a reference signal included in the PUSCH for channel estimation.

[0128] (A3) SRS settings The PUSCH configuration is an information element indicating the configuration of the SRS resource of the UE 100A. When the NCR-UE 100B acquires such an SRS configuration, the NCR-UE 100B can receive (and demodulate) the SRS of the UE 100A. The NCR-UE 100B uses the SRS for channel estimation.

[0129] (A4)C-RNTI The C-RNTI is a temporary identifier that the gNB 200 assigns to the UE 100A. The C-RNTI may be necessary when the NCR-UE 100B receives (and demodulates) the signals of the above-mentioned channels (e.g., PUCCH, PUSCH). Therefore, by the NCR-UE 100B acquiring the C-RNTI of the UE 100A, it becomes possible to smoothly receive (and demodulate) the signals of the above-mentioned channels.

[0130] In step S104, the UE 100A transmits a UE-UL signal. The NCR device 500A receives the UE-UL signal. The UE-UL signal includes at least one of a PUCCH, a PUSCH, and an SRS. Here, the NCR-UE 100B receives the UE-UL signal based on the resource configuration information received from the gNB 200 in step S103.

[0131] In step S105, the NCR device 500A relays (transfers) the UE-UL signal received from the UE 100A in step S104 to the gNB 200. The gNB 200 receives the relayed UE-UL signal. The gNB 200 performs channel estimation based on the received UE-UL signal and determines antenna weights that direct beams toward the NCR-UE 100B (i.e., the NCR device 500A). The antenna weights are sometimes referred to as precoding matrices.

[0132] In step S106, the NCR-UE 100B performs channel estimation based on the UE-UL signal received from the UE 100A in step S104.

[0133] In step S107, NCR-UE 100B controls the beam of NCR device 500A using the channel estimation result in step S106 (beamforming control). For example, NCR-UE 100B determines an antenna weight that directs a beam toward UE 100A, and sets the antenna weight in NCR device 500A.

[0134] In step S108, the gNB 200 transmits a UE-DL signal while directing a beam toward the NCR-UE 100B (NCR device 500A). The NCR device 500A receives the UE-DL signal.

[0135] In step S109, the NCR device 500A relays (transfers) to the UE 100A the UE-DL signal received from the gNB 200 in step S108. Here, the NCR device 500A transmits the UE-DL signal while directing a beam toward the UE 100A in accordance with the beamforming control in step S107.

[0136] In step S110, the UE 100A transmits a UE-UL signal. The NCR device 500A receives the UE-UL signal. The NCR device 500A may receive the UE-UL signal using the antenna weight set in step S107 (i.e., the directivity set in step S107).

[0137] In step S111, the NCR device 500A relays (transfers) the UE-UL signal received from the UE 100A in step S104 to the gNB 200. The gNB 200 receives the relayed UE-UL signal.

[0138] Fig. 16 is a diagram showing another example of the operation flow of the first operation pattern. In Fig. 16, non-essential steps are indicated by dashed lines. Here, differences from the operation in Fig. 15 will be explained.

[0139] In step S103, the gNB 200 transmits to the NCR-UE 100B a message including resource configuration information indicating resources required for the NCR-UE 100B to receive a UE-UL signal from the UE 100A. The NCR-UE 100B receives the message. The message may include, in addition to at least one of the information elements (A1) to (A4) above, channel state information between the gNB 200 and the NCR device 500A and / or antenna weight information (precoding matrix information) of the gNB 200.

[0140] In step S131, the UE 100A transmits a UE-UL signal including beam control information. The NCR device 500A receives the UE-UL signal. The NCR-UE 100B receives the UE-UL signal based on the resource configuration information received from the gNB 200 in step S103. The UE-UL signal may be a PUCCH. The PUCCH may include PMI as beam control information. The beam control information is information based on a channel estimation result performed on the UE 100A side. Specifically, the beam control information is information reflecting the channel state (including the NCR device 500A) between the gNB 200 and the UE 100A. The beam control information may be information indicating an antenna weight to which a beam is directed from the NCR device 500A to the UE 100A.

[0141] In step S132, the NCR-UE 100B acquires the antenna weight information included in the UE-UL signal received from the UE 100A in step S131.

[0142] In step S133, the NCR-UE 100B controls the beam of the NCR device 500A using the antenna weight information acquired in step S132 (beamforming control). For example, the NCR-UE 100B sets the antenna weight indicated by the antenna weight information to the NCR device 500A. Alternatively, if the antenna weight information indicates the channel state between the gNB 200 and the UE 100A, the NCR-UE 100B may also take into consideration the channel state notified from the gNB 200 in step S103 (i.e., the channel state between the gNB 200 and the NCR device 500A) to derive the channel state between the NCR device 500A and the UE 100A. The NCR-UE 100B uses the derived channel state to determine an antenna weight for directing a beam toward the UE 100A, and sets the antenna weight to the NCR device 500A.

[0143] Other operations in FIG. 16 are the same as those in FIG.

[0144] In the present first operation pattern, an example has been described in which there is one UE 100A that is a relay target of the NCR device 500A, but there may be a plurality of UEs 100A that are relay targets of the NCR device 500A. The NCR-UE 100B may perform the operation of the present first operation pattern for each of the plurality of UEs 100A. In step S103, the gNB 200 may transmit a message including resource setting information for each of the plurality of UEs 100A to the NCR-UE 100B.

[0145] Here, in this message, an index may be assigned to the resource configuration information of each of the multiple UEs 100A. After transmitting the resource configuration information in step S103, the gNB 200 may transmit to the NCR-UE 100B an activation command (for example, DCI or MAC CE) including an index specifying the resource configuration information to be actually applied. In response to receiving the activation command, the NCR-UE 100B may apply the resource configuration information specified by the index.

[0146] Alternatively, a case may be assumed in which there are multiple UEs 100A to be relayed by the NCR device 500A and the multiple UEs 100A are close to each other. In such a case, the NCR-UE 100B may perform the operation of the first operation pattern for one UE 100A that represents the multiple UEs 100A. Furthermore, in step S103, the gNB 200 may transmit a message including resource configuration information for the one UE 100A to the NCR-UE 100B.

[0147] (7.2) Second movement pattern In this second operation pattern, the setting information transmitted from the gNB 200 to the NCR-UE 100B includes mode setting information for switching the control mode related to beamforming among multiple control modes. The NCR-UE 100B controls the NCR device 500A to direct a beam toward the UE 100A using the control mode set in accordance with the mode setting information. Such mode setting information may be transmitted by an RRC message, a MAC CE, or a DCI. The mode setting information may be information specifying a control mode after switching to the NCR-UE 100B. Alternatively, the mode setting information may be information permitting the NCR-UE 100B to use a specific control mode.

[0148] The multiple control modes may be two or more of a "gNB control mode" in which the NCR-UE100B controls the NCR device 500A in accordance with control from the gNB200, an "autonomous control mode" in which the NCR-UE100B autonomously controls the NCR device 500A without control from the gNB200, a "hybrid control mode" that uses both control from the gNB200 and autonomous control by the NCR-UE100B, and a "beam sweeping control mode" that sequentially switches the beam direction of the NCR device 500A.

[0149] The "gNB control mode" is a mode in which the NCR-UE 100B controls the NCR device 500A based on specific control from the gNB 200. In the "gNB control mode," for example, the gNB 200 sequentially instructs the NCR-UE 100B on the beam (antenna weight) to be applied to the NCR-UE 100B by DCI or MAC CE.

[0150] The "autonomous control mode" is a mode in which the NCR-UE 100B autonomously controls the NCR device 500A without specific control from the gNB 200. In the "autonomous control mode," for example, the NCR-UE 100B determines the beam (antenna weight) to be applied to the NCR-UE 100B, and the NCR-UE 100B controls the beam of the NCR device 500A. The first operation pattern described above can be considered a type of "autonomous control mode." In the "autonomous control mode," the NCR-UE 100B may estimate the position of the UE 100A using a sensor such as a proximity radar, and the NCR-UE 100B may control the beam of the NCR device 500A according to the estimated position.

[0151] The "hybrid control mode" is a mode in which the gNB 200 performs rough control of the NCR device 500A, and the NCR-UE 100B autonomously performs specific control of the NCR device 500A. In the "hybrid control mode," for example, the gNB 200 specifies the beam direction (directivity direction) in 45-degree increments, and the NCR-UE 100B autonomously performs fine adjustments of that 45 degrees ±5 degrees.

[0152] The "beam sweeping control mode" is a mode in which the NCR-UE 100B sequentially switches the beam direction of the NCR device 500A. For example, the NCR device 500A sequentially switches the beam direction so as to rotate the beam 360 degrees horizontally. The UE 100A detects and responds to a signal from the NCR device 500A in one of the beam directions. As a result, the direction in which the UE 100A is located can be estimated. After the direction in which the UE 100A is located is estimated, the gNB 200 may switch the NCR-UE 100B to the "autonomous control mode."

[0153] Here, an example has been described in which the mode setting information is an information element for switching the "beamforming control mode" of the NCR device 500A, but this information element may also be used for switching other control modes. For example, the mode setting information may include an identifier indicating which of the "beamforming control mode," "timing switching control mode," and "on / off control control mode" is to be applied. "Timing switching" refers to, for example, switching the timing between uplink and downlink in TDD (Time Division Duplex). "On / off control" refers to, for example, switching the operation of the NCR device 500A between stopping (off) and starting (on).

[0154] Fig. 17 is a diagram showing an example of an operation flow of this second operation pattern, in which non-essential steps are indicated by dashed lines.

[0155] In step S201, the gNB 200 transmits a message including mode configuration information for switching the control mode for beamforming among multiple control modes to the NCR-UE 100B. The NCR-UE 100B receives the message. The message may be a message similar to the downlink signaling described above. For example, the message may be RRC Reconfiguration, MAC CE, or DCI. The mode configuration information includes at least one information element from the following (B1) to (B3).

[0156] (B1) Identifier indicating the applicable subject The identifier indicates, for example, one of the "beamforming control mode," "timing switching control mode," and "on / off control mode."

[0157] (B2) Mode Identifier The identifier indicates, for example, one of "gNB control mode," "autonomous control mode," "hybrid control mode," and "beam sweeping control mode." Note that the control mode may not necessarily be specified by such an explicit identifier, and the NCR-UE100B may determine the control mode based on a setting from the gNB200. That is, the gNB200 may implicitly indicate the control mode to the NCR-UE100B. For example, the NCR-UE100B may determine the gNB control mode when various settings for the gNB control mode have been made, and may determine the autonomous control mode when various settings for the autonomous control mode have been made.

[0158] (B3) Timing Information The timing information indicates the timing at which the control mode indicated by the mode identifier is applied or permitted to be applied by a period or slot number, etc. If a period is specified, periodic mode switching is possible.

[0159] In step S202, the NCR-UE 100B determines the control mode based on the mode setting information received in step S201 from the gNB 200. For example, the NCR-UE 100B may switch the "beamforming control mode" between the "gNB control mode" and the "autonomous control mode."

[0160] In the "gNB control mode," in step S203, the gNB 200 transmits beam control information for controlling the beam of the NCR-UE 100 B to the NCR-UE 100 B. The NCR-UE 100 B receives the beam control information.

[0161] In step S204, NCR-UE 100B controls the beam of NCR device 500A in the control mode determined in step S202 (beamforming control). The subsequent operations are the same as those in the first operation pattern described above.

[0162] (8) Examples of changes to relay devices and control terminals In the above-described embodiment, an example has been described in which the relay device relaying wireless signals between the gNB 200 and the UE 100 (UE 100A) is a repeater device (NCR device 500A) that amplifies and forwards the received wireless signals. However, the relay device relaying wireless signals between the gNB 200 and the UE 100 (UE 100A) may be a Reconfigurable Intelligent Surface (RIS) device that changes the propagation direction of incident radio waves (wireless signals) by reflection or refraction. The term "NCR" in the above-described embodiment can be replaced with "RIS." The RIS can perform beamforming (directivity control) similar to the NCR by changing the characteristics of a metamaterial. The RIS may be capable of changing the range (distance) of the beam, similar to a lens, by controlling the reflection direction and refraction direction of each unit element. For example, the RIS may be configured to control the reflection direction and refraction direction of each unit element and to focus (direct the beam) on a nearby UE or a distant UE.

[0163] The RIS device 500B shown in FIG. 18 is a reflection-type RIS device 500B. Such a RIS device 500B changes the propagation direction of an incident radio wave by reflecting the radio wave. Here, the reflection angle of the radio wave is variably settable. The RIS device 500B reflects the radio wave incident from the gNB 200 toward each of the UE 100A1 and the UE 100A2. The RIS device 500B may also reflect the radio waves incident from each of the UE 100A1 and the UE 100A2 toward the gNB 200. The RIS device 500B dynamically changes the reflection angle of the radio wave. For example, in the communication resource between the gNB 200 and the UE 100A1, the RIS device 500B reflects the radio wave incident from the gNB 200 toward the UE 100A1 and / or reflects the radio wave incident from the UE 100A1 toward the gNB 200. Here, the communication resource includes a time-direction resource and / or a frequency-direction resource. In the communication resources between gNB200 and UE100A2, RIS device 500B reflects radio waves incident from gNB200 toward UE100A2 and / or reflects radio waves incident from UE100A2 toward gNB200.

[0164] The RIS device 500B shown in FIG. 19 is a transparent RIS device 500B. Such a RIS device 500B changes the propagation direction of an incident radio wave by refracting the radio wave. Here, the refraction angle of the radio wave can be variably set. The RIS device 500B refracts the radio wave incident from the gNB 200 toward each of the UE 100A1 and the UE 100A2. The RIS device 500B may also refract the radio waves incident from each of the UE 100A1 and the UE 100A2 toward the gNB 200. The RIS device 500B dynamically changes the refraction angle of the radio wave. For example, in the communication resource between the gNB 200 and the UE 100A1, the RIS device 500B refracts the radio wave incident from the gNB 200 toward the UE 100A1 and / or refracts the radio wave incident from the UE 100A1 toward the gNB 200. In the communication resources between gNB200 and UE100A2, RIS device 500B refracts radio waves incident from gNB200 toward UE100A2 and / or refracts radio waves incident from UE100A2 toward gNB200.

[0165] In this modification, as shown in FIG. 20 , a new UE (hereinafter referred to as "RIS-UE") 100C is introduced, which is a control terminal for controlling the RIS device 500B. The RIS-UE 100C establishes a wireless connection with the gNB 200 and performs wireless communication with the gNB 200, thereby controlling the RIS device 500B in cooperation with the gNB 200. This makes it possible to achieve efficient coverage expansion using the RIS device 500B while suppressing increases in installation costs and decreases in installation flexibility for the RIS device 500B. The RIS-UE 100C controls the RIS device 500B in accordance with a RIS control signal from the gNB 200.

[0166] The RIS-UE 100C may be configured separately from the RIS device 500B. For example, the RIS-UE 100C may be located near the RIS device 500B and electrically connected to the RIS device 500B. The RIS-UE 100C may be connected to the RIS device 500B via a wired or wireless connection. Alternatively, the RIS-UE 100C may be configured integrally with the RIS device 500B. The RIS-UE 100C and the RIS device 500B may be fixedly installed, for example, on a wall or window. The RIS-UE 100C and the RIS device 500B may be mobile, installed, for example, in a vehicle. Furthermore, one RIS-UE 100C may control multiple RIS devices 500B.

[0167] 21 is a diagram showing the configuration of a RIS-UE 100C and a RIS device 500B according to this modified example. As shown in FIG. 21, the RIS-UE 100C includes a receiving unit 110, a transmitting unit 120, a control unit 130, and an interface 140. This configuration is similar to that of the above-described embodiment.

[0168] The RIS device 500B includes a RIS 510B and a RIS control unit 520B. The RIS 510B is a metasurface made of metamaterial. For example, the RIS 510B is configured by arranging extremely small structures relative to the wavelength of radio waves in an array. By varying the shape of the structures depending on their placement, it is possible to arbitrarily design the direction and beam shape of the reflected waves. The RIS 510B may be a transparent dynamic metasurface. The RIS 510B may be configured by overlaying a transparent glass substrate on a transparent metasurface substrate on which a large number of small structures are regularly arranged. By minutely moving the overlaid glass substrate, it may be possible to dynamically control three patterns: a mode that transmits incident radio waves, a mode that transmits and reflects some of the radio waves, and a mode that reflects all of the radio waves.

[0169] The RIS control unit 520B controls the RIS 510B in response to a RIS control signal from the control unit 130 of the RIS-UE 100C. The RIS control unit 520B may include at least one processor and at least one actuator. The processor decodes the RIS control signal from the control unit 130 of the RIS-UE 100C and drives the actuator in response to the RIS control signal. Note that when the RIS-UE 100C and the RIS device 500B are configured integrally, the control unit 130 of the RIS-UE 100C and the RIS control unit 520B of the RIS device 500B may also be configured integrally.

[0170] (9) Other embodiments The NCR / RIS control information transmitted from the gNB 200 to the NCR-UE 100B or the RIS-UE 100C may be information for controlling the direction and focal length of the beam relayed (output) by the NCR device 500A or the RIS device 500B. Information for controlling the direction is, for example, the antenna weight, as described above. Information for controlling the focal length is information for the NCR device 500A or the RIS device 500B to focus the beam depending on the distance between the NCR device 500A or the RIS device 500B and the UE 100A. Such information may be information indicating the distance between the NCR device 500A or the RIS device 500B and the UE 100A. Alternatively, such information may be information indicating the focal length (e.g., a focal range such as near or far). The NCR device 500A or the RIS device 500B adjusts the focal length of the beam based on the information. In the case of the RIS device 500B, the reflection (or refraction) angle of the outer elements of the metasurface surface and the reflection (or refraction) angle of the inner elements are controlled (made different) at different angles, thereby adjusting the focal length of the beam like a lens.

[0171] In the above-described embodiment, the frequency control information may include a cell ID that identifies a cell and / or a bandwidth portion (BWP) ID that identifies a bandwidth portion (BWP). A BWP refers to a frequency band that is part of a cell.

[0172] The above-described operational flows are not limited to being implemented independently, but can also be implemented by combining two or more operational flows. For example, some steps of one operational flow may be added to another operational flow, or some steps of one operational flow may be replaced with some steps of another operational flow. In each flow, it is not necessary to execute all steps, and only some steps may be executed.

[0173] In the above embodiment, an example in which the base station is an NR base station (gNB) has been described, but the base station may also be an LTE base station (eNB). The base station may also be a relay node such as an IAB (Integrated Access and Backhaul) node. The base station may also be a DU (Distributed Unit) of the IAB node.

[0174] A program may be provided that causes a computer to execute each process performed by UE100 (NCR-UE100B, RIS-UE100C) or gNB200. The program may be recorded on a computer-readable medium. Using the computer-readable medium, the program can be installed on a computer. Here, the computer-readable medium on which the program is recorded may be a non-transitory recording medium. The non-transitory recording medium is not particularly limited, and may be, for example, a recording medium such as a CD-ROM or a DVD-ROM. Furthermore, circuits that execute each process performed by UE100 or gNB200 may be integrated, and at least a part of UE100 or gNB200 may be configured as a semiconductor integrated circuit (chip set, SoC: System on a chip).

[0175] As used in this disclosure, the terms "based on" and "depending on" do not mean "based only on" or "depending only on," unless expressly stated otherwise. The term "based on" means both "based only on" and "based at least in part on." Similarly, the term "depending on" means both "based only on" and "at least in part on." Furthermore, "obtain" may mean obtaining information from stored information, obtaining information from information received from another node, or obtaining information by generating the information. The terms "include," "comprise," and variations thereof do not mean including only the listed items, but may also mean including only the listed items or including additional items in addition to the listed items. Furthermore, as used in this disclosure, the term "or" is not intended to mean an exclusive or. Furthermore, any reference to elements using designations such as "first," "second," etc., as used in this disclosure does not generally limit the quantity or order of those elements. These designations may be used herein as a convenient method of distinguishing between two or more elements. Thus, reference to first and second elements does not imply that only two elements may be employed therein or that the first element must precede the second element in some manner. In this disclosure, where articles are added by translation, such as a, an, and the in English, these articles shall include the plural unless the context clearly indicates otherwise.

[0176] The above describes the embodiments in detail with reference to the drawings, but the specific configuration is not limited to that described above, and various design changes can be made within the scope that does not deviate from the gist of the invention.

[0177] This application claims priority from Japanese Patent Application No. 2022-071094 (filed April 22, 2022), the entire contents of which are incorporated herein by reference.

[0178] (Addendum) The following additional notes are about the features of the above-described embodiment.

[0179] (1) A control terminal for controlling a relay device that relays radio signals between a base station and a user device in a mobile communication system, a receiving unit that receives, from the base station, configuration information used by the relay device to direct a beam toward the user device; a control unit that controls the relay device to direct the beam toward the user device based on the setting information. Control terminal.

[0180] (2) the setting information includes resource setting information indicating resources required for the control terminal to receive an uplink signal from the user equipment; the receiving unit receives the uplink signal from the user equipment using the resource indicated by the resource configuration information; The control unit controls the relay device to direct the beam toward the user device in response to the received uplink signal. The control terminal described in (1) above.

[0181] (3) The control unit Estimating a channel condition between the control terminal and the user equipment using the received uplink signal; and controlling the relay device to point the beam toward the user device in response to the estimated channel conditions. The control terminal according to (1) or (2) above.

[0182] (4) the uplink signal includes beam control information; The control unit Obtaining the beam control information included in the received uplink signal; Controlling the relay device to direct the beam toward the user device in accordance with the acquired beam control information. The control terminal according to (2) or (3) above.

[0183] (5) The receiving unit receives an RRC (Radio Resource Control) message including the resource configuration information from the base station. A control terminal according to any one of (2) to (4) above.

[0184] (6) The resource configuration information includes at least one of PUCCH configuration information indicating a configuration of a PUCCH (Physical Uplink Control Channel) of the user equipment, PUSCH configuration information indicating a configuration of a PUSCH (Physical Uplink Shared Channel) of the user equipment, SRS configuration information indicating a configuration of an SRS (Sounding Reference Signal) of the user equipment, and a C-RNTI (Cell Radio Network Temporary Identifier) ​​assigned to the user equipment. A control terminal according to any one of (2) to (5) above.

[0185] (7) the setting information includes mode setting information for switching a control mode related to beamforming among a plurality of control modes; The control unit controls the relay device to direct the beam toward the user device using the control mode set in accordance with the mode setting information. A control terminal according to any one of (1) to (6) above.

[0186] (8) The plurality of control modes includes a base station control mode in which the control terminal controls the relay device according to control from the base station. The control terminal described in (7) above.

[0187] (9) The plurality of control modes includes an autonomous control mode in which the control terminal autonomously controls the relay device without control from the base station. A control terminal according to (7) or (8) above.

[0188] (10) The plurality of control modes further includes a hybrid control mode in which control from the base station and autonomous control of the control terminal are used in combination. A control terminal according to any one of (7) to (9) above.

[0189] (11) The plurality of control modes further includes a beam sweeping control mode in which the beam direction of the relay device is sequentially switched. A control terminal according to any one of (7) to (10) above.

[0190] (12) The receiving unit receives, from the base station, an RRC (Radio Resource Control) message including the mode setting information, a MAC (Medium Access Control) CE (Control Element) including the mode setting information, or a DCI (Downlink Control Information) including the mode setting information. A control terminal according to any one of (7) to (11) above.

[0191] (13) The mode setting information includes information for switching one of the control mode of the beamforming of the relay device, the control mode of timing switching of the relay device, and the control mode of on / off control of the relay device. A control terminal according to any one of (7) to (12) above.

[0192] (14) The mode setting information includes information specifying the timing of switching the control mode. A control terminal according to any one of (7) to (13) above.

[0193] (15) A base station used in a mobile communication system having a control terminal that controls a relay device that relays radio signals between the base station and a user device, a transmitter that transmits to the control terminal setting information used by the relay device to direct a beam to the user device; Base station.

[0194] (16) In a mobile communication system A communication method executed by a control terminal that controls a relay device that relays radio signals between a base station and a user device, comprising: receiving, from the base station, configuration information used by the relay device to direct a beam toward the user device; and controlling the relay device to direct the beam toward the user device based on the setting information. Communication method. [Explanation of symbols]

[0195] 1: Mobile communication system 100:UE 100B: NCR-UE 100C:RIS-UE 110: Receiving unit 120: Transmitter 130: Control unit 140: Interface 200 :gNB 210: Transmission unit 220: Receiving unit 230: Control unit 240: Backhaul communication unit 500A:NCR device 500B :RIS device 510A: Wireless unit 510a: Antenna part 510b :RF circuit 510c: Directivity control section 520A: NCR control section 520B: RIS control unit

Claims

1. A control terminal for controlling a relay device that relays radio signals between a network node and a user device in a mobile communication system, a receiving unit that receives, from the network node, configuration information used by the relay device to direct a beam toward the user device; a control unit that controls the relay device to direct the beam toward the user device based on the setting information, The setting information includes an identifier corresponding to each of a plurality of control modes related to beamforming, and information indicating a period during which the control mode corresponding to the identifier is applied. Control terminal.

2. A network node used in a mobile communication system having a control terminal that controls a relay device that relays radio signals between the network node and a user device, a transmitter configured to transmit to the control terminal setting information used by the relay device to direct a beam to the user device; The setting information includes an identifier corresponding to each of a plurality of control modes related to beamforming, and information indicating a period during which the control mode corresponding to the identifier is applied. Network node.

3. A communication method executed by a control terminal that controls a relay device that relays radio signals between a network node and a user device in a mobile communication system, comprising: receiving, from the network node, configuration information used by the relay device to direct a beam toward the user equipment; and controlling the relay device to direct the beam toward the user device based on the setting information; The setting information includes an identifier corresponding to each of a plurality of control modes related to beamforming, and information indicating a period during which the control mode corresponding to the identifier is applied. Communication method.

4. A chipset for a control terminal that controls a relay device that relays radio signals between a network node and a user device in a mobile communication system, receiving, from the network node, configuration information used by the relay device to direct a beam toward the user device; and controlling the relay device to direct the beam toward the user device based on the setting information; The setting information includes an identifier corresponding to each of a plurality of control modes related to beamforming, and information indicating a period during which the control mode corresponding to the identifier is applied. Chipset.

5. A control terminal controls a relay device that relays radio signals between a network node and a user device in a mobile communication system. receiving, from the network node, configuration information used by the relay device to direct a beam toward the user device; and controlling the relay device to direct the beam toward the user device based on the setting information; The setting information includes an identifier corresponding to each of a plurality of control modes related to beamforming, and information indicating a period during which the control mode corresponding to the identifier is applied. program.

6. A mobile communication system including a control terminal that controls a relay device that relays radio signals between a network node and a user device, The control terminal receiving, from the network node, configuration information used by the relay device to direct a beam toward the user device; controlling the relay device to direct the beam toward the user device based on the setting information; The setting information includes an identifier corresponding to each of a plurality of control modes related to beamforming, and information indicating a period during which the control mode corresponding to the identifier is applied. Mobile communication system.

Images