Communication control method, network-controlled repeater, network node, chip set, program, and mobile communication system

Abstract

To provide a communication control method for controlling a smart repeater (SR) device capable of beamforming, and a network-controlled repeater.SOLUTION: In a communication control method in a mobile communication system, an SR wireless terminal (SR-UE100B) that controls an SR device (500) capable of beamforming and that is a repeater device that relays wireless communication between a base station (gNB200) and a wireless terminal (UE100A) executes processing including: establishing a wireless connection with the base station; and the SR wireless terminal transmitting SR device information indicating at least one of the capabilities of the SR device and the control state of the SR device to the base station via wireless communication.SELECTED DRAWING: Figure 6

Description

[Technical field]

[0001] The present disclosure relates to a communication control method, a wireless terminal, and a base station for use in a mobile communication system. [Background technology]

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

[0003] Radio waves in high frequency bands such as millimeter wave bands or terahertz wave bands have a high degree of linearity, which makes it difficult to reduce the coverage of base stations. To solve this problem, smart repeater (SR) devices that are repeater devices that relay wireless communications between base stations and wireless terminals and are capable of beamforming have been attracting attention (see, for example, Non-Patent Document 1). Such SR devices can expand the coverage of base stations while suppressing interference, for example, by amplifying radio waves received from base stations and transmitting them directional. [Prior art documents] [Non-patent literature]

[0004] [Non-Patent Document 1] 3GPP contribution: RWS-210275, “5G eMBB Evolution To 5G Advanced” Summary of the Invention

[0005] A communication control method according to a first aspect includes a repeater-controlled radio terminal that controls a base station-controlled repeater that relays wireless communication between a base station and a wireless terminal, establishing a wireless connection with the base station, and the repeater-controlled radio terminal transmitting base station-controlled repeater information indicating at least one of the capabilities of the base station-controlled repeater and the control state of the base station-controlled repeater to the base station via wireless communication.

[0006] A wireless terminal according to a second aspect is a wireless terminal that performs wireless communication with a base station in a mobile communication system, and includes: a control unit that controls a base station-controlled repeater that relays wireless communication between the base station and other wireless terminals; and a transmission unit that transmits base station-controlled repeater information indicating at least one of the capabilities of the base station-controlled repeater and the control state of the base station-controlled repeater to the base station via wireless communication.

[0007] A base station according to a third aspect is a base station that performs wireless communication with wireless terminals in a mobile communication system, and includes a receiving unit that receives, via wireless communication, base station controlled repeater information indicating at least one of the capabilities of the base station controlled repeater and the control state of the base station controlled repeater from a wireless terminal that controls a base station controlled repeater that relays wireless communication between the base station and other wireless terminals. [Brief description of the drawings]

[0008] [Figure 1] 1 is a diagram showing a configuration of a mobile communication system according to an embodiment; [Diagram 2] A diagram showing the configuration of a protocol stack of a wireless interface of a user plane that handles data. [Diagram 3] FIG. 2 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 showing an application scenario of an SR device according to an embodiment. [Diagram 5] FIG. 1 is a diagram showing an application scenario of an SR device according to an embodiment. [Figure 6] FIG. 1 is a diagram illustrating an example of the configuration of a protocol stack in a mobile communication system having an SR device and an SR-UE (SR wireless terminal) according to an embodiment. [Figure 7] A diagram showing the configuration of an SR-UE and an SR device according to one embodiment. [Figure 8] A diagram showing the configuration of a gNB (base station) according to one embodiment. [Figure 9] A diagram showing downlink signaling from a gNB to an SR-UE in one embodiment. [Figure 10] FIG. 13 is a diagram illustrating a configuration of SR control settings according to an embodiment. [Figure 11] FIG. 13 is a diagram illustrating a configuration of SR control settings according to an embodiment. [Figure 12] A diagram showing uplink signaling from an SR-UE to a gNB according to one embodiment. [Figure 13] FIG. 2 is a diagram showing a configuration of SR device capability information according to an embodiment. [Figure 14] FIG. 2 is a diagram showing a configuration of SR device capability information according to an embodiment. [Figure 15] FIG. 11 is a diagram showing a configuration of control state information according to an embodiment. [Figure 16] FIG. 11 is a diagram showing a configuration of control state information according to an embodiment. [Figure 17] A diagram showing operations related to measurements by an SR-UE according to one embodiment. [Figure 18] FIG. 4 is a diagram illustrating an operation according to the first embodiment. [Figure 19] FIG. 11 is a diagram illustrating an operation according to the second embodiment. [Figure 20] FIG. 11 is a diagram showing a configuration example of SR control setting and control timing information according to the second embodiment. [Figure 21] FIG. 13 is a diagram illustrating an operation according to the third embodiment. [Figure 22] FIG. 13 is a diagram illustrating an operation according to the fourth embodiment. [Diagram 23] FIG. 13 is a diagram illustrating an operation according to the fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] It is believed that efficient coverage expansion can be achieved by operating the SR device in conjunction with the operation of the base station. However, the technical specifications of conventional mobile communication systems do not prescribe a mechanism for the base station to control the SR device, which makes it difficult to efficiently expand coverage using the SR device.

[0010] Therefore, the present disclosure provides a communication control method, a wireless terminal, and a base station that enable efficient coverage expansion using an SR 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] [Embodiment] (Configuration of a mobile communication system) First, a configuration of a mobile communication system according to an embodiment will be described. Fig. 1 is a diagram showing a configuration of a mobile communication system 1 according to an embodiment. The mobile communication system 1 complies with the 3GPP standard 5th Generation System (5GS). In the following description, 5G / NR will be taken as an example, but 4G / LTE may be applied at least partially to the mobile communication system 1. A sixth generation (6G) system may be applied at least partially to the mobile communication system 1.

[0013] The mobile communication system 1 includes a wireless terminal (UE: User Equipment) 100, a 5G radio access network (NG-RAN: Next Generation Radio Access Network) 10, and a 5G core network (5GC: 5G Core Network) 20.

[0014] The UE 100 is a mobile wireless communication device. For example, the UE 100 is a mobile phone terminal (including a smartphone), a tablet terminal, a notebook 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 the 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, and the like. 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 for performing wireless communication with the UE 100. One cell belongs to one carrier frequency.

[0016] In addition, gNBs can also be connected to the Evolved Packet Core (EPC), which is the core network of LTE. LTE base stations can also be connected to 5GC. LTE base stations and gNBs can also be connected via an inter-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 Non-Access Stratum (NAS) signaling. The UPF controls data forwarding. The AMF and the 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] As shown in FIG. 2, 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 the UE 100 and the PHY layer of the gNB 200 via a physical channel.

[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 a transport channel. The MAC layer of gNB200 includes a scheduler. The scheduler determines the uplink and downlink transport format (transport block size, modulation and coding scheme (MCS)) and the resource blocks to be assigned to UE100.

[0022] The RLC layer transmits data to the RLC layer on the receiving side by using the functions of the MAC layer and the 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 a logical channel.

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

[0024] The SDAP layer maps IP flows, which are units for QoS (Quality of Service) control by the core network, to radio bearers, which are units for QoS control by the AS (Access Stratum). Note that if the RAN is connected to the EPC, the 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] As shown in FIG. 3, 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] Between the RRC layer of the UE 100 and the RRC layer of the gNB 200, RRC signaling for various settings is transmitted. 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 radio connection (RRC connection) between the RRC of the UE 100 and the RRC of the gNB 200, the UE 100 is in an RRC connected state. When there is no radio connection (RRC connection) between the RRC of the UE 100 and the RRC of the gNB 200, the UE 100 is in an RRC idle state. When the radio connection between the RRC of the UE 100 and the RRC of the gNB 200 is suspended, the UE 100 is in an RRC inactive state.

[0028] The NAS layer 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 300. The UE 100 has an application layer and the like in addition to a protocol of the radio interface.

[0029] (Application scenarios for SR devices) Next, an application scenario of the SR device according to an embodiment will be described. Figures 4 and 5 are diagrams showing application scenarios of the SR device according to an embodiment. The SR device is an example of a base station controlled repeater.

[0030] 5G / NR is capable of wideband transmission using higher frequency bands than 4G / LTE. Radio waves in high frequency bands such as the millimeter wave band or the terahertz wave band have high linearity, so that the reduction of the coverage of the gNB 200 becomes an issue. In FIG. 4, the UE 100A may be located outside the coverage area of ​​the gNB 200, for example, outside the area where radio waves can be received directly from the gNB 200. There may be an obstruction between the gNB 200 and the UE 100A, and the UE 100A may not be able to communicate with the gNB 200 within line of sight.

[0031] In the embodiment, a smart repeater (SR) device 500 that is a repeater device that relays wireless communication between the gNB 200 and the UE 100A and is capable of beamforming is introduced into the mobile communication system 1. For example, the SR device 500 amplifies radio waves (radio signals) received from the gNB 200 and transmits the radio signals by directional transmission. Specifically, the SR device 500 receives radio signals transmitted by the gNB 200 by beamforming. Then, the SR device 500 amplifies the received radio signals and transmits the amplified radio signals by directional transmission. Here, the SR device 500 may transmit radio signals with fixed directivity. The SR device 500 may transmit radio signals by a variable (adaptive) directional beam. This allows the coverage of the gNB 200 to be efficiently expanded.

[0032] Note that, although an example of applying the SR device 500 to downlink communication from the gNB 200 to the UE 100A has been described here, the SR device 500 can also be applied to uplink communication from the UE 100A to the gNB 200.

[0033] In the embodiment, as shown in FIG. 5, a new UE (hereinafter, referred to as "SR-UE") for controlling the SR device 500 is introduced. The SR-UE is an example of a repeater control radio terminal. The SR-UE 100B is also an example of an SR radio terminal. The SR-UE 100B controls the SR device 500 in cooperation with the gNB 200 by establishing a radio connection with the gNB 200 and performing radio communication with the gNB 200. This makes it possible to realize efficient coverage extension using the SR device 500. The SR-UE 100B controls the SR device 500 according to the SR control setting from the gNB 200. The SR-UE 100B may autonomously control the SR device 500 according to a pre-set SR control setting even if the SR control setting is not set from the gNB 200. The SR control setting is an example of a repeater control setting.

[0034] The SR-UE 100B may be configured separately from the SR device 500. For example, the SR-UE 100B may be located near the SR device 500 and electrically connected to the SR device 500. The SR-UE 100B may be connected to the SR device 500 by wire or wirelessly. Alternatively, the SR-UE 100B may be configured integrally with the SR device 500. The SR-UE 100B and the SR device 500 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 SR-UE 100B and the SR device 500 may be installed, for example, in a vehicle or the like and may be movable. Also, one SR-UE 100B may control multiple SR devices 500.

[0035] In the example shown in FIG. 5, the SR device 500 dynamically or quasi-statically changes the beam to be transmitted or received. For example, the SR device 500 forms a beam toward each of the UE 100A1 and the UE 100A2. The SR device 500 may also form a beam toward the gNB 200. For example, in a communication resource between the gNB 200 and the UE 100A1, the SR device 500 transmits a radio wave received from the gNB 200 toward the UE 100A1 by beamforming, and / or transmits a radio wave received from the UE 100A1 toward the gNB 200 by beamforming. In a communication resource between the gNB 200 and the UE 100A2, the SR device 500 transmits a radio wave received from the gNB 200 toward the UE 100A2 by beamforming, and / or transmits a radio wave received from the UE 100A2 toward the gNB 200 by beamforming. Instead of or in addition to forming a beam, the SR device 500 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. In the following, a beam (beam forming) may be read as a null (null steering). Alternatively, a beam (beam forming) may be read as a beam and a 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 SR device 500 and an SR-UE 100B according to an embodiment.

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

[0038] The SR-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 SR-UE 100B exchanges downlink signaling and / or uplink signaling, which will be described later, with the gNB 200 through at least one of PHY, MAC, RRC, and F1-AP. If the SR-UE 100B is a type or part of a base station, the SR-UE 100B may exchange with the gNB 200 through an Xn AP (Xn-AP), which is an interface between base stations.

[0039] (SR-UE and SR device configuration) Next, a description will be given of the configuration of the SR-UE 100B (SR radio terminal) and the SR device 500 according to one embodiment. Fig. 7 is a diagram showing the configuration of the SR-UE 100B and the SR device 500 according to one embodiment.

[0040] As shown in FIG. 7, the SR-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 radio waves (radio signals) received by the antenna into baseband signals (received signals) and outputs the signals 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 the baseband signals (transmitted signals) output by the control unit 130 into radio signals and transmits the radio signals from the antenna.

[0042] The control unit 130 performs various controls in the SR-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 the 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 executes the functions of at least one layer of PHY, MAC, RRC, and F1-AP.

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

[0044] The SR device 500 includes a wireless unit 510 and an SR control unit 520. The wireless unit 510 includes an antenna unit 510a including a plurality of 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) wireless signals transmitted and received by the antenna unit 510a. The RF circuit 510b may convert an analog wireless signal into a digital signal and reconvert it into an analog signal after digital signal processing. The directivity control unit 510c may perform analog beamforming by analog signal processing or digital beamforming by digital signal processing. Alternatively, the directivity control unit 510c may perform hybrid analog and digital beamforming.

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

[0046] In one embodiment, the receiver 110 of the SR-UE 100B receives one or more SR control settings used to control the SR device 500 from the gNB 200 by wireless communication. The controller 130 of the SR-UE 100B controls the SR device 500 based on the one or more SR control settings. The SR control settings are an example of downlink signaling from the gNB 200 to the SR-UE 100B. This enables the gNB 200 to control the SR device 500 via the SR-UE 100B.

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

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

[0049] As shown in FIG. 8, the gNB 200 includes a transmitter 210, a receiver 220, a control unit 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 the 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 processing.

[0052] The backhaul communication unit 240 is connected to adjacent 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., the functions are divided), and both units may be connected to each other via an F1 interface.

[0053] In one embodiment, the transmitter 210 of the gNB 200 transmits, by wireless communication, one or more SR control settings used to control the SR device 500 to the SR-UE 100B that controls the SR device 500. The SR control settings are an example of downlink signaling from the gNB 200 to the SR-UE 100B. This enables the gNB 200 to control the SR device 500 via the SR-UE 100B.

[0054] In one embodiment, the receiver 220 of the gNB 200 receives SR device information indicating at least one of the capability of the SR device 500 and the control state of the SR device 500 from the SR-UE 100B that controls the SR device 500 by wireless communication. The SR device information is an example of uplink signaling from the SR-UE 100B to the gNB 200. This enables the gNB 200 to grasp the capability and control state of the SR device 500.

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

[0056] (1) Downlink signaling FIG. 9 is a diagram showing downlink signaling from gNB200 to SR-UE100B according to one embodiment.

[0057] The gNB 200 (transmitter 210) transmits downlink signaling to the SR-UE 100B. The downlink signaling may be an RRC message which is signaling of the RRC layer, a MAC CE (Control Element) which is signaling of the MAC layer, and / or downlink control information (DCI) which is signaling of the PHY layer. The downlink signaling may be UE-specific signaling and / or broadcast signaling. The downlink signaling may be a fronthaul message (e.g., an F1-AP message). If the SR-UE 100B is a type or a part of a base station, the SR-UE 100B may communicate with the gNB 200 via an AP of Xn (Xn-AP) which is an interface between base stations.

[0058] For example, as shown in FIG. 9, the gNB 200 (transmitter 210) transmits downlink signaling including an SR control setting used for controlling the SR device 500 to the SR-UE 100B that has established a wireless connection with the gNB 200 (step S1). The gNB 200 (transmitter 210) may include the SR control setting in an RRC Reconfiguration message, which is a type of RRC message for an individual UE, and transmit the message to the SR-UE 100B. The downlink signaling may be a message of a layer higher than the RRC layer (e.g., an SR 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.

[0059] In addition, the SR-UE 100B (transmitter 120) may transmit, on the uplink, a response message to the downlink signaling from the gNB 200. The response message may be transmitted in response to the SR device 500 completing the setting specified by the downlink signaling or receiving the setting.

[0060] As shown in Fig. 10, the SR control setting may include frequency setting information for setting a center frequency of radio waves (e.g., a component carrier) to be relayed by the SR device 500. When the SR control setting received from the gNB 200 includes frequency setting information, the SR-UE 100B (control unit 130) controls the SR device 500 to relay radio waves having a center frequency indicated by the frequency setting information. The SR control setting may include multiple pieces of frequency setting information for setting different center frequencies. By including frequency setting information in the SR control setting, the gNB 200 can specify, via the SR-UE 100B, the center frequency of radio waves to be relayed by the SR device 500.

[0061] The SR control setting may include mode setting information for setting an operation mode of the SR device 500. The mode setting information may be associated with frequency setting information (center frequency). The operation mode may be any of a mode in which the SR device 500 performs omnidirectional transmission and / or reception, a mode in which the SR device 500 performs fixed directional transmission and / or reception, a mode in which the SR device 500 performs transmission and / or reception by a variable directional beam, and a mode in which the SR device 500 performs MIMO (Multiple Input Multiple Output) relay transmission. The operation mode may be any of a beamforming mode (i.e., a mode that emphasizes improvement of a desired wave) and a null steering mode (i.e., a mode that emphasizes suppression of an interference wave). When the SR control setting received from the gNB 200 includes mode setting information, the SR-UE 100B (control unit 130) controls the SR device 500 to operate in an operation mode indicated by the mode setting information. Since the SR control setting includes mode setting information, the gNB 200 can specify the operating mode of the SR device 500 via the SR-UE 100B.

[0062] Here, the mode in which the SR device 500 performs non-directional transmission and / or reception is a mode in which the SR device 500 performs relay in all directions, and may be referred to as an omni mode.

[0063] The mode in which the SR device 500 transmits and / or receives with fixed directivity may be a directional mode realized by one directional antenna and / or a beamforming mode realized by applying fixed phase and amplitude control (antenna weight control) to multiple antennas. Any of these modes may be specified (set) by the gNB 200 to the SR-UE 100B.

[0064] The mode in which the SR device 500 transmits and / or receives using a variable directional beam may be a mode in which analog beamforming is performed or a mode in which digital beamforming is performed. The mode may be a mode in which hybrid beamforming is performed. The mode may 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 SR-UE 100B.

[0065] In addition, in an operation mode in which beamforming is performed, beam setting information described below may be provided from gNB200 to SR-UE100B.

[0066] The mode in which the SR device 500 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, and / or a mode in which transmission diversity is performed. Any of these modes may be specified (set) by the gNB 200 to the SR-UE 100B.

[0067] The operation mode may include a mode in which relay transmission by the SR device 500 is turned on (activated) and a mode in which relay transmission by the SR device 500 is turned off (deactivated). Any of these modes may be specified (set) by the gNB 200 to the SR-UE 100B.

[0068] The SR control setting may include beam setting information for setting a transmission direction, a transmission weight, or a beam pattern when the SR device 500 performs directional transmission. The beam setting information may be associated with frequency setting information (center frequency). The beam setting information may include a PMI (Precoding Matrix Indicator). By including the beam setting information in the SR control setting, the gNB 200 can set the transmission directivity of the SR device 500 in the SR mode. -Can be controlled via UE100B.

[0069] The SR control setting may include amplification setting information for setting the degree to which the SR device 500 amplifies radio waves (amplification gain) or the transmission output power. The amplification setting information may be associated with frequency setting information (center frequency). The amplification setting information may be information for setting any one of the amplifier gain, the beamforming gain, and the antenna gain of the SR device 500. The amplification setting information may be information for setting the transmission output power of the SR device 500.

[0070] As shown in FIG. 11, when the SR-UE 100B controls a plurality of SR devices 500, the gNB 200 (transmitting unit 210) may transmit an SR control setting to the SR-UE 100B for each SR device 500. In this case, the SR control setting may include an identifier (SR device identifier) ​​of the corresponding SR device 500. The SR-UE 100B (control unit 130) that controls a plurality of SR devices 500 determines the SR device 500 to which the SR control setting is applied based on the SR device identifier included in the SR control setting received from the gNB 200. Note that the SR device identifier may be transmitted from the SR-UE 100B to the gNB 200 together with the SR control setting even when the SR-UE 100B controls only one SR device 500.

[0071] In this way, the SR-UE 100B (control unit 130) controls the SR device 500 based on the SR control setting from the gNB 200. This enables the gNB 200 to control the SR device 500 via the SR-UE 100B.

[0072] (2) Uplink Signaling FIG. 12 is a diagram showing uplink signaling from SR-UE 100B to gNB 200 according to one embodiment.

[0073] The SR-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, a MAC CE, which is signaling of the MAC layer, and / or 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) and / 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 SR 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 gNB 200 (transmitter 210) may transmit a response message in response to the uplink signaling from the SR-UE 100B on the downlink, and the SR-UE 100B (receiver 110) may receive the response message.

[0074] For example, the SR-UE 100B (transmitter 120) that has established a wireless connection with the gNB 200 transmits SR device information indicating at least one of the capabilities of the SR device 500 and the control state of the SR device 500 to the gNB 200 by wireless communication (step S2). The SR device information is an example of base station controlled repeater information. Specifically, the SR device information includes at least one of SR device capability information indicating the capabilities of the SR device 500 and control state information indicating the control state of the SR device 500. The SR-UE 100B (transmitter 120) may include the SR device information in a UE Capability message or a UE Assistant Information message, which is a type of RRC message, and transmit the message to the gNB 200. The SR-UE 100B (transmitter 120) may transmit the SR device information (SR device capability information and / or control state information) to the gNB 200 in response to a request or inquiry from the gNB 200. The SR-UE 100B (transmission unit 120) may periodically transmit the SR device information (particularly, the control state information) to the gNB 200 in accordance with a setting from the gNB 200. This transmission period may be set from the gNB 200 to the SR-UE 100B.

[0075] As shown in Fig. 13, the SR device capability information may include supported frequency information indicating the frequencies supported by the SR device 500. The supported frequency information may be a numerical value or an index indicating the center frequency of the frequencies supported by the SR device 500, and / or a numerical value or an index indicating the range of frequencies supported by the SR device 500. When the SR device capability information received from the SR-UE 100B includes the supported frequency information, the gNB 200 (control unit 230) can ascertain the frequencies supported by the SR device 500 based on the supported frequency information. Then, the gNB 200 (control unit 230) may set the center frequency of the radio waves targeted by the SR device 500 within the range of frequencies supported by the SR device 500.

[0076] The SR device capability information may include mode capability information related to an operation mode that the SR device 500 can support or switching between operation modes. As described above, the operation mode may be at least one of a mode in which the SR device 500 performs non-directional transmission and / or reception, a mode in which the SR device 500 performs fixed directional transmission and / or reception, a mode in which the SR device 500 performs transmission and / or reception using a variable directional beam, and a mode in which the SR device 500 performs MIMO (Multiple Input Multiple Output) relay transmission. The operation mode may be either a beamforming mode (i.e., a mode that emphasizes improvement of a desired wave) or a null steering mode (i.e., a mode that emphasizes suppression of an interference wave). The mode capability information may be information indicating which of these operation modes the SR device 500 can support. The mode capability information may be information indicating which of these operation modes mode switching is possible between. When the SR device capability information received from the SR-UE 100B includes mode capability information, the gNB 200 (control unit 230) can grasp the operation mode and mode switching supported by the SR device 500 based on the mode capability information. Then, the gNB 200 (control unit 230) may set the operation mode of the SR device 500 within the range of the grasped operation mode and mode switching.

[0077] The SR device capability information may include beam capability information indicating a beam variable range, a beam variable resolution, or the number of variable patterns when the SR device 500 transmits and / or receives using a variable directional beam. The beam capability information may be, for example, information indicating a variable range of a beam angle based on the horizontal or vertical direction (for example, controllable from 30° to 90°) and / or information indicating an absolute angle. The beam capability information may be expressed by a direction and / or an elevation angle to which the beam is directed. The beam capability information may be information indicating an angle change for each variable step (for example, 5° / step horizontally, 10° / step vertically) and / or information indicating the number of variable steps (for example, 10 steps horizontally, 20 steps vertically). The beam capability information may be information indicating the number of variable patterns of the beam in the SR device 500 (for example, a total of 10 patterns including beam patterns 1 to 10). When the SR device capability information received from the SR-UE 100B includes beam capability information, the gNB 200 (control unit 230) can grasp the beam angle change or beam pattern that the SR device 500 can support based on the beam capability information. Then, the gNB 200 (control unit 230) may set the beam of the SR device 500 within the range of the grasped beam angle change or beam pattern. The beam capability information may be null capability information. In the case of null capability information, it indicates the null control capability when null steering is performed.

[0078] In addition, the gNB 200 may not know the actual beam direction for each variable pattern. For example, the gNB 200 first sets the beam pattern 1 in the SR device 500, transmits to the UE 100A via the SR device 500, and knows the reception state of the UE 100A (understands the situation by ACK / NACK, CSI feedback, measurement report, etc.). Secondly, the gNB 200 sets the beam pattern 2 in the SR device 500, transmits to the UE 100A via the SR device 500, and knows the reception state of the UE 100A. Thirdly, the gNB 200 sets the beam pattern 3 in the SR device 500, transmits to the UE 100A via the SR device 500, and knows the reception state of the UE 100A. Finally, the gNB 200 identifies the beam pattern with the best reception state of the UE 100A, and sets the pattern in the SR device 500.

[0079] The SR device capability information may include control delay information indicating a control delay time in the SR device 500. For example, the control delay information is information indicating a delay time (for example, 1 ms, 10 ms, etc.) from the timing when the UE 100 receives the SR control setting or the timing when the UE 100 transmits a setting completion for the SR control setting to the gNB 200 until the control (changing the operation mode or changing the beam) according to the SR control setting is completed. When the SR device capability information received from the SR-UE 100B includes the control delay information, the gNB 200 (control unit 230) can grasp the control delay time in the SR device 500 based on the control delay information.

[0080] The SR device capability information may include amplification characteristic information related to the amplification characteristic or output power characteristic of the radio wave in the SR device 500. The amplification characteristic information may be information indicating the amplifier gain (dB), beamforming gain (dB), or antenna gain (dBi) of the SR device 500. The amplification characteristic information may be information indicating the amplification variable range (e.g., 0 dB to 60 dB) in the SR device 500. The amplification characteristic information may be information indicating the number of steps (e.g., 10 steps) of the amplification degree that the SR device 500 can change, or the amplification degree 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 SR device 500. The amplification characteristic information may be information indicating the number of steps (e.g., 10 steps) of the output power that the SR device 500 can change, or the output power per variable step (e.g., 10 dBm / step).

[0081] The SR device capability information may include location information indicating the installation location of the SR device 500. 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 SR device 500 based on 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 a place where the antenna unit 510a of the SR device 500 is installed.

[0082] The SR device capability information may include antenna information indicating the number of antennas the SR device 500 has. The antenna information may be information indicating the number of antenna ports the SR device 500 has. The antenna information may be information indicating the degree of freedom of directivity control (beam or null formation). The degree of freedom indicates how many beams can be formed (controlled), and is usually "(number of antennas)-1". For example, in the case of two antennas, the degree of freedom is 1. In the case of two antennas, a beam pattern resembling a figure of eight is formed, but the degree of freedom is 1 because directivity control is possible in only one direction.

[0083] As shown in FIG. 14, when the SR-UE 100B controls a plurality of SR devices 500, the SR-UE 100B (transmission unit 120) may transmit SR device capability information to the gNB 200 for each SR device 500. In this case, the SR device capability information may include an identifier (SR device identifier) ​​of the corresponding SR device 500. Also, when the SR-UE 100B controls a plurality of SR devices 500, the SR-UE 100B (transmission unit 120) may transmit information indicating at least one of the identifiers of the plurality of SR devices 500 and the number of the plurality of SR devices 500. Note that the SR device identifier may be transmitted from the SR-UE 100B to the gNB 200 together with the SR device capability information even when the SR-UE 100B controls only one SR device 500.

[0084] 15, the control state information may include frequency state information indicating the center frequency of the radio waves that the SR device 500 is relaying. The frequency state information may be information indicating the center frequency of the latest (current) radio waves that the SR device 500 is relaying at the time of transmitting the control state information. When the control state information received from the SR-UE 100B includes frequency state information, the gNB 200 (control unit 230) can grasp the center frequency of the radio waves that the SR device 500 is relaying based on the frequency state information.

[0085] The control state information may include mode state information indicating the operation mode of the SR device 500. The mode state information may be information indicating the latest (current) operation mode of the SR device 500 at the time of transmitting the control state information. As described above, the operation mode may be any of the following modes: a mode in which the SR device 500 performs omnidirectional transmission and / or reception, a mode in which the SR device 500 performs fixed directional transmission and / or reception, a mode in which the SR device 500 performs transmission and / or reception by a variable directional beam, and a mode in which the SR device 500 performs MIMO (Multiple Input Multiple Output) relay transmission. The operation mode may be any of the following modes: a beamforming mode (i.e., a mode that emphasizes improvement of a desired wave) and a null steering mode (i.e., a mode that emphasizes suppression of an interference wave). When the control state information received from the SR-UE 100B includes mode state information, the gNB 200 (control unit 230) can grasp the operation mode of the SR device 500 based on the mode state information.

[0086] The control state information may include beam state information indicating a transmission direction, a transmission weight, or a beam pattern when the SR device 500 performs directional transmission. The beam state information may be information indicating the latest (current) transmission direction, transmission weight, or beam pattern of the SR device 500 at the time of transmitting the control state information. When the control state information received from the SR-UE 100B includes beam state information, the gNB 200 (control unit 230) can grasp the state of the beam in the SR device 500 based on the beam state information.

[0087] As shown in FIG. 16, when the SR-UE 100B controls a plurality of SR devices 500, the SR-UE 100B (transmitting unit 120) may transmit control state information to the gNB 200 for each SR device 500. In this case, the control state information may include an identifier (SR device identifier) ​​of the corresponding SR device 500. Note that the SR device identifier may be transmitted from the SR-UE 100B to the gNB 200 together with the control state information even when the SR-UE 100B controls only one SR device 500.

[0088] In this way, the SR-UE 100B (transmitter 120) transmits, by wireless communication, SR device information indicating at least one of the capability of the SR device 500 and the control state of the SR device 500 to the gNB 200. This enables the gNB 200 to grasp the capability and control state of the SR device 500.

[0089] (3) Operation related to measurements by SR-UE 17 is a diagram showing an operation related to measurement by the SR-UE 100B according to one embodiment. The SR-UE 100B measures a radio state. Here, the SR-UE 100B is configured integrally with the SR device 500 or is located in the vicinity of the SR device 500. Therefore, the radio state in the SR-UE 100B can be treated as being equivalent to the radio state in the SR device 500.

[0090] As shown in FIG. 17, in step S11, the gNB 200 (transmitter 210) transmits a setting related to measurement (measurement setting) to the SR-UE 100B that has established a wireless connection with the gNB 200. The measurement setting sets, in the SR-UE 100B, measurement and a report of the measurement result for at least one of the radio waves received by the SR device 500 from the gNB 200 and the radio waves received by the SR device 500 from the UE 100 (for example, the above-mentioned UE 100A). The measurement setting may include information for setting at least one of a frequency to be measured, a signal to be measured (for example, DM-RS or CSI-RS which are downlink reference signals, and / or SRS which is an uplink reference signal), a resource to be measured (for example, a subframe, a resource element, and / or a signal sequence), and a report type. The report type may be a periodic report or an event triggered report.

[0091] In step S12, the SR-UE 100B (control unit 130) performs measurement of the radio state (radio measurement) based on the measurement configuration received from the gNB 200 in step S11. The SR device 500 (control unit 130) performs radio measurement (i.e., downlink measurement) on the radio waves received by the SR device 500 from the gNB 200. The SR device 500 (control unit 130) may perform radio measurement (i.e., uplink measurement) on the radio waves received by the SR device 500 from the UE 100.

[0092] The measurement by the SR-UE 100B may be a radio resource management (RRM) measurement mainly performed in the RRC layer. The measurement by the SR-UE 100B may be a channel state information (CSI) measurement mainly performed in the PHY layer. The measurement result obtained by the RRM measurement may be, for example, at least one of a reference signal received power (RSRP), a reference signal received quality (RSRQ), and a received signal strength indicator (RSSI). The measurement result obtained by the CSI measurement may be, for example, at least one of a channel quality indicator (CQI), a precoding matrix indicator (PMI), a CSI-RS resource indicator (CRI), a strong layer indicator (SLI), a rank indicator (RI), and an L1-RSRP.

[0093] In step S13, the SR-UE 100B (transmission unit 120) transmits a report including the measurement result obtained in step S12 to the gNB 200. The measurement result is at least one of an RRM measurement result and a CSI measurement result.

[0094] In step S14, the gNB 200 (control unit 230) controls the transmission of radio waves (for example, the transmission directivity of the beam) based on the report of the measurement result received from the SR-UE 100B in step S13. For example, the gNB 200 (control unit 230) controls the transmission directivity (and / or the reception directivity) so that the beam is directed toward the SR device 500. The gNB 200 (control unit 230) may reconfigure the SR device 500 via the SR-UE 200B.

[0095] In this way, the gNB 200 (control unit 230) can perform appropriate beamforming using the measurement results by the SR-UE 100B by treating the radio conditions in the SR-UE 100B as equivalent to the radio conditions in the SR device 500.

[0096] [Example] Next, based on the above-mentioned embodiment, a first embodiment to a fifth embodiment will be described. These embodiments are not limited to being implemented separately and independently, and two or more embodiments may be combined and implemented. In addition, in the operation flow of each of the following embodiments, it is not necessary to execute all steps, and only some of the steps may be executed.

[0097] (1) First Example FIG. 18 is a diagram showing the operation according to the first embodiment.

[0098] As shown in FIG. 18, in step S101, the SR-UE 100B is in an RRC idle state or an RRC inactive state.

[0099] In step S102, the gNB 200 (transmitting unit 210) broadcasts SR support information indicating that the gNB 200 supports the SR-UE 100B. For example, the gNB 200 (transmitting unit 210) broadcasts a system information block (SIB) including the SR support information. The SR support information may be information indicating that the SR-UE 100B is accessible. Alternatively, the gNB 200 (transmitting unit 210) may broadcast SR non-support information indicating that the gNB 200 does not support the SR-UE 100B. The SR non-support information may be information indicating that the SR-UE 100B is not accessible.

[0100] An SR-UE 100B (control unit 130) that has not established a wireless connection with a gNB 200 may determine, in response to receiving SR 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 SR-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.

[0101] On the other hand, if the gNB 200 does not broadcast SR support information (or broadcasts SR non-support information), the SR-UE 100B (control unit 130) that has not established a wireless connection with the gNB 200 may determine that it is not possible to access (establish a connection with) the gNB 200. This allows the SR-UE 100B to establish a wireless connection only to a gNB 200 that can handle the SR-UE 100B.

[0102] In addition, when the gNB 200 is congested, the gNB 200 may broadcast access restriction information that restricts access from the UE 100. However, unlike the normal UE 100, the SR-UE 100B can be regarded as an entity on the network side. Therefore, the SR-UE 100B may ignore the access restriction information from the gNB 200. For example, when the SR-UE 100B (control unit 130) receives SR support information from the gNB 200, the SR-UE 100B may perform an operation to establish a wireless connection with the gNB 200 even if the gNB 200 broadcasts the access restriction information. For example, the SR-UE 100B (control unit 130) may not execute (or may ignore) UAC (Unified Access Control). Alternatively, a special value indicating that the access is an SR-UE may be used as either or both of AC / AI (Access Category / Access Identity) used in UAC.

[0103] In step S103, the SR-UE 100B (control unit 130) starts a random access procedure for the gNB 200. In the random access procedure, the SR-UE 100B (transmission unit 120) transmits a random access preamble (Msg1) and an RRC message (Msg3) to the gNB 200. Also, in the random access procedure, the SR-UE 100B (reception unit 110) receives a random access response (Msg2) and an RRC message (Msg4) from the gNB 200.

[0104] In step S104, when establishing a wireless connection with the gNB 200, the SR-UE 100B (transmitter 120) may transmit SR-UE information indicating that the UE is an SR-UE to the gNB 200. For example, during a random access procedure with the gNB 200, the SR-UE 100B (transmitter 120) transmits to the gNB 200 the SR-UE information included in a message for the random access procedure (e.g., Msg1, Msg3, Msg5). The gNB 200 (controller 230) recognizes that the accessed UE 100 is the SR-UE 100B based on the SR-UE information received from the SR-UE 100B, and can, for example, remove the SR-UE 100B from the access restriction target (i.e., accept the access).

[0105] In step S105, the SR-UE 100B transitions from the RRC idle state or the RRC inactive state to the RRC connected state.

[0106] In step S106, the gNB 200 (transmitter 120) transmits a capability inquiry message to the SR-UE 100B to inquire about the capability of the SR-UE 100B. The SR-UE 100B (receiver 110) receives the capability inquiry message.

[0107] In step S107, the SR-UE 100B (transmitter 120) transmits a capability information message including the above-mentioned SR device capability information to the gNB 200. The gNB 200 (receiver 220) receives the capability information message. The gNB 200 (controller 230) grasps the capability of the SR device 500 based on the received capability information message.

[0108] In step S108, the gNB 200 (transmitter 210) transmits an RRC message (measurement configuration message) including measurement configuration information for configuring measurement by the SR-UE 100B to the SR-UE 100B. The SR-UE 100B (receiver 110) receives the measurement configuration message. The SR-UE 100B (controller 130) performs radio measurement based on the measurement configuration message.

[0109] In step S109, the SR-UE 100B (transmitter 120) transmits a report (measurement report) including the radio measurement result to the gNB 200. The gNB 200 (controller 230) may perform beamforming so that a beam is directed to the SR-UE 100B (SR device 500) based on the measurement report received from the SR-UE 100B. The gNB 200 (controller 230) may determine the SR control setting to be set in the SR-UE 100B based on the measurement report received from the SR-UE 100B.

[0110] In step S110, the gNB 200 (transmitter 120) transmits, to the SR-UE 100B, an SR control setting used for controlling the SR device 500. The gNB 200 (transmitter 120) may transmit, to the SR-UE 100B, an RRC Reconfiguration message including the SR control setting. The SR-UE 100B (receiver 110) receives the SR control setting.

[0111] In step S111, the SR-UE 100B (control unit 130) controls the SR device 500 based on the SR control setting received from the gNB 200. The SR-UE 100B (control unit 130) may control the SR device 500 by notifying the SR device 500 (SR control unit 520) of the SR control setting received from the gNB 200.

[0112] In step S112, when the control (setting change) of the SR device 500 is completed, the SR-UE 100B (transmitter 120) transmits a control setting completion message (for example, an RRC Reconfiguration Complete message) to the gNB 200. Here, the SR-UE 100B (controller 130) may determine the control completion based on a notification (feedback) from the SR device 500 (SR controller 520). The gNB 200 (receiver 220) receives the control setting completion message.

[0113] (2) Second Example In the above-described embodiment and the first example, it is mainly assumed that the SR device 500 is quasi-statically controlled. In the second example, it is assumed that the SR device 500 is dynamically controllable. Fig. 19 is a diagram showing the operation according to the second example.

[0114] As shown in Fig. 19, in step S201, the gNB 200 (transmitter 120) transmits one or more SR control settings and control timing information indicating the timing at which each of the one or more SR control settings is applied to the SR-UE 100B. For example, the gNB 200 (transmitter 120) transmits an RRC message (e.g., an RRC Reconfiguration message) including the SR control setting and the control timing information to the SR-UE 100B. The SR-UE 100B (receiver 110) receives the SR control setting and the control timing information. Note that step S201 corresponds to step S110 in the first embodiment described above.

[0115] In step S202, the SR-UE 100B (control unit 130) controls the SR device 500 based on the SR control setting and the control timing information received in step S201. Specifically, the SR-UE 100B (control unit 130) controls the SR device 500 in accordance with the SR control setting associated with the control timing information at the timing indicated by the control timing information.

[0116] FIG. 20 is a diagram showing an example of the configuration of the SR control setting and control timing information according to the second embodiment.

[0117] As shown in Fig. 20, SR control setting #1 and SR control setting #2 are each associated with different control timing information. For example, the control timing information associated with SR control setting #1 indicates that SR control setting #1 is applied at frame numbers #1, #3, #5, . . . The control timing information associated with SR control setting #2 indicates that SR control setting #2 is applied at frame numbers #2, #4, #6, . . . The SR-UE 100B (control unit 130) can ascertain the current frame number based on the frame number broadcast by the gNB 200 (for example, the frame number in the master information block, etc.).

[0118] Here, the frame number may be a hyper system frame number (H-SFN), a system frame number (SFN), or a subframe number. The control timing information may include a slot number and / or an OFDM symbol number, and / or an absolute time (e.g., GPS time) instead of or in addition to the frame number. In this way, the multiple SR control settings are applied to the control of the SR device 500 at different timings. The control timing information includes information indicating the application timing of each of the multiple SR control settings.

[0119] 20 shows an example in which the application timing of the SR control setting is specified by a frame number or the like. However, the control timing information may be configured in a bitmap format consisting of bits each associated with a frame number. For example, the SR-UE 100B (control unit 130) applies the SR control setting at a frame number that is "1" in the bitmap, and does not apply the SR control setting at a radio frame that is 0. The control timing information may further include a start frame number to which the bitmap is applied.

[0120] According to the second embodiment, the SR device 500 can be dynamically controlled by transmitting control timing information indicating the timing at which the SR control setting is applied from the gNB 200 to the SR-UE 100B.

[0121] For example, the gNB 200 can set a beam direction and an amplification degree for each radio frame to the SR device 500 via the SR-UE 100B. The gNB 200 may set a transmission PMI for each radio frame to the SR device 500 via the SR-UE 100B. For example, when the SR device 500 applies weighting to a signal received from the UE 100A via one antenna and transmits (relays) the signal to the gNB 200 using multiple transmission antennas, the transmission PMI can be controlled so that the signal is orthogonal to uplink signals from other UEs at the gNB receiving antenna end.

[0122] (3) Third Example In the third embodiment, an example of interlocking the transmission of a synchronization signal block (SS / PBCH Block: SSB) with the control of the SR device 500 will be described. The SSB includes a primary synchronization signal (PSS), a secondary synchronization signal (SSS), a PBCH (Physical Broadcast Channel), and a demodulation reference signal (DMRS). For example, the SSB may be composed of four consecutive OFDM symbols in the time domain. The SSB may also be composed of 240 consecutive subcarriers (20 resource blocks) in the frequency domain. The PBCH is a physical channel that carries a master information block (MIB). FIG. 21 is a diagram showing the operation according to the third embodiment.

[0123] In SSB transmission, the gNB 200 performs beam sweeping by changing the weighting (directivity) for each SSB. When the SR device 500, specifically, the SR 510, is present in the propagation path between the gNB 200 and the UE 100, the communication quality changes depending on the control of the SR device 500. Therefore, by linking the beam sweeping with the control of the SR device 500, the SSB transmission in which the SR device 500 is present can be optimized.

[0124] As shown in Fig. 21, gNB200 (transmitter 210) transmits multiple SSBs at different timings and with different beams. Fig. 21 shows an example in which gNB200 (transmitter 210) transmits a total of seven SSBs, SSB1 to SSB7. Here, gNB200 (transmitter 210) transmits a set of SSB3 to SSB5 (hereinafter referred to as the "SSB set") with the same weighting (i.e., the same beam characteristics). Although an example in which the number of SSBs constituting the SSB set is three is shown, the number of SSBs constituting the SSB set may be two, or four or more.

[0125] The gNB200 (transmitting unit 210) may transmit information on each SSB included in the SSB set (for example, SSB identifier and / or transmission timing information) to the SR-UE100B, for example, by an RRC message. Furthermore, the gNB200 (transmitting unit 210) may transmit an SR control configuration to the SR-UE100B in association with information on each SSB included in the SSB set. That is, the gNB200 (transmitting unit 210) may transmit an SR control configuration to the SR-UE100B for each SSB included in the SSB set. The gNB200 (transmitting unit 210) may specify a different application timing for each SR control configuration by the above-mentioned control timing information. The control timing information for the SSB may be the same information element as the above-mentioned control timing information, or an information element different from the above-mentioned control timing information.

[0126] The SR-UE 100B applies different SR control settings to each SSB included in the SSB set to control the SR device 500. Fig. 21 shows an example in which the SR device 500 transmits each of the SSBs 3 to 5 included in the SSB set in different directions. Here, the transmission direction of each SSB from the SR device 500 is linked to the transmission direction of each original SSB transmitted by the gNB 200.

[0127] Thus, in the third embodiment, the gNB 200 transmits a plurality of SSBs (SSB set) having different transmission timings to the SR device 500. The SR control setting is associated with the plurality of SSBs. Specifically, the gNB 200 transmits the plurality of SSBs to the SR device 500 with the same beam characteristics. Based on the SR control setting, the SR-UE 100B controls the transmission direction of radio waves when the SR device 500 performs directional transmission for each of the plurality of SSBs. This makes it possible to make the transmission direction different for each SSB included in the SSB set.

[0128] In the third embodiment, an example has been described in which the SR-UE 100B controls the SR device 500 according to the SR control setting from the gNB 200. However, the SR-UE 100B may autonomously control the SR device 500 according to a preset SR control setting even if the SR control setting is not set from the gNB 200. In this case, the SR-UE 100B may notify the gNB 200 of the preset SR control setting as the above-mentioned control state information. Details of such an operation will be described in a fourth embodiment described later.

[0129] (4) Fourth Example In the fourth embodiment, an example will be described in which the SR-UE 100B autonomously controls the SR device 500 and notifies the gNB 200 of the current control state. The SR-UE 100B may autonomously control the SR device 500 based on auxiliary information from the gNB 200. Fig. 22 is a diagram showing the operation according to the fourth embodiment.

[0130] As shown in FIG. 22, in step S301, SR-UE 100B (control unit 130) autonomously controls SR device 500.

[0131] In step S302, the gNB200 (transmitter 210) transmits to the SR-UE100B a control state inquiry for inquiring of the UE100 about the above-mentioned control state information, or a control state transmission setting for setting the UE100 to transmit the above-mentioned control state information. The gNB200 (transmitter 210) may transmit to the SR-UE100B an RRC message including the control state inquiry or the control state transmission setting. The control state transmission setting may include information for setting a cycle for transmitting the control state information from the SR-UE100B to the gNB200, or information for setting a trigger event for transmitting the control state information from the SR-UE100B to the gNB200 (for example, an event that the radio state (RSRP, etc.) of the SR-UE100B exceeds a threshold, or an event that the radio state of the SR-UE100B falls below a threshold).

[0132] In step S303, the SR-UE 100B (transmitter 120) transmits control state information to the gNB 200 based on the control state inquiry or control state transmission setting received from the gNB 200. The gNB 200 (control unit 130) grasps the current control state in the SR-UE 100B (SR device 500) based on the control state information received from the gNB 200.

[0133] According to the fourth embodiment, even when the SR-UE 100B autonomously controls the SR device 500, the gNB 200 can grasp the current control state.

[0134] (5) Fifth Example In the fifth embodiment, an example will be described in which the SR-UE 100B performs handover between the gNBs 200. Fig. 23 is a diagram showing operations according to the fifth embodiment.

[0135] 23, in step S401, the SR-UE 100B (control unit 130) transmits a measurement report to the gNB 200A. The gNB 200A (control unit 230) determines handover of the SR-UE 100B to the gNB 200B based on the measurement report received from the SR-UE 100B.

[0136] In step S402, the gNB 200A (backhaul communication unit 240) transmits a handover request message requesting handover of the SR-UE 100B to the gNB 200B. Here, the gNB 200A (backhaul communication unit 240) may include the SR control setting that the gNB 200A has set in the SR-UE 100B in the handover request message and transmit it to the gNB 200B. The gNB 200A (backhaul communication unit 240) may include the SR device information that the gNB 200A has received from the SR-UE 100B in the handover request message and transmit it to the gNB 200B.

[0137] The gNB 200B (control unit 230) determines whether or not to approve the handover of the SR-UE 100B based on the handover request received from the gNB 200A. Here, the description will proceed on the assumption that it has been determined that the handover is approved.

[0138] In step S403, the gNB 200B (the backhaul communication unit 240) transmits a handover acknowledgement message to the gNB 200A. The gNB 200B (the backhaul communication unit 240) may transmit the SR control setting to be set in the SR-UE 100B after the handover to the gNB 200A by including the SR control setting in the handover acknowledgement message.

[0139] In step S404, the gNB 200A (transmission unit 210) transmits a handover command to the SR-UE 100B to instruct a handover to the gNB 200B. The gNB 200A (transmission unit 210) may include the SR control setting received from the gNB 200B in the handover command and transmit it to the SR-UE 100B.

[0140] In step S405, the SR-UE 100B (control unit 130) establishes a wireless connection with the gNB 200B by performing a random access procedure with the gNB 200B in response to receiving the handover command. After the handover, the SR-UE 100B (control unit 130) may control the SR device 500 based on the SR control setting included in the handover command.

[0141] According to the fifth embodiment, even when the SR-UE 100B performs a handover between gNBs 200, the handover of the SR-UE 100B can be appropriately controlled.

[0142] [Other embodiments] Once the SR-UE 100B is connected to the gNB 200 or SR control is performed from the gNB 200, it is desirable for the SR-UE 100B to maintain the RRC connected state. When the SR-UE 100B transitions to the RRC inactive state or the RRC idle state (or when the SR-UE 100B is powered on), the SR-UE 100B may control the SR device 500 to an omni mode or characteristics as close to this as possible. This makes it possible to prevent adverse effects such as the SR device 500 not being controlled by the gNB 200 unintentionally narrowing the existing coverage area.

[0143] The above-mentioned operational flows are not limited to being implemented separately and independently, but can 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.

[0144] 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 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.

[0145] A program may be provided that causes a computer to execute each process performed by the UE100 (SR-UE100B) or the gNB200. The program may be recorded in a computer-readable medium. The computer-readable medium can be used to install the program in the computer. Here, the computer-readable medium on which the program is recorded may be a non-transient recording medium. The non-transient recording medium is not particularly limited, and may be, for example, a recording medium such as a CD-ROM or a DVD-ROM. In addition, a circuit that executes each process performed by the UE100 (SR-UE100B) or the gNB200 may be integrated, and at least a part of the UE100 (SR-UE100B) or the gNB200 may be configured as a semiconductor integrated circuit (chip set, SoC: System on a chip).

[0146] As used in this disclosure, the terms "based on" and "depending on" do not mean "based only on" or "depending only on," unless otherwise specified. 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 "based at least in part on." Additionally, "obtain / acquire" may mean obtaining information from stored information, from information received from other nodes, or by generating information. The terms "include," "comprise," and variations thereof do not mean including only the items listed, but may include only the items listed, or may include additional items in addition to the items listed. Additionally, the term "or" as used in this disclosure is not intended to be an exclusive or. Additionally, any reference to elements using designations such as "first," "second," etc., as used in this disclosure is not intended to 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 a first and a second element 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 are intended to include the plural unless the context clearly indicates otherwise.

[0147] 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, etc. are possible without departing from the spirit of the invention.

[0148] This application claims priority to Japanese Patent Application No. 2021-113807 (filed July 8, 2021), the entire contents of which are incorporated herein by reference. [Explanation of symbols]

[0149] 1: Mobile communication systems 100:UE 100B:SR-UE 110: Receiving unit 120: Transmitter 130: Control section 140: Interface 200: gNB 210: Transmission unit 220: Receiving unit 230: Control section 240: Backhaul communication unit 500 :SR device 510: Wireless unit 510a: Antenna section 510b :RF circuit 510c: Directivity control section 520: SR control section

Claims

1. a network controlled repeater receiving control information from a network node; the network-controlled repeater amplifying and relaying wireless signals between the network node and user equipment based on the control information; When the network-controlled repeater establishes a wireless connection with the network node, the network-controlled repeater transmits information to the network node indicating that the wireless connection is a connection made by the network-controlled repeater. Communications control method.

2. The network node broadcasts access restriction information that restricts access from the user equipment; the network-controlled repeater ignoring the access restriction information. The communication control method according to claim 1 .

3. The information is included in Msg5 in the random access procedure. The communication control method according to claim 1 .

4. 1. A network-controlled repeater, comprising: A receiver for receiving control information from a network node; a control unit configured to amplify and relay a radio signal between the network node and a user equipment based on the control information; a transmitter that, when establishing a wireless connection with the network node, transmits to the network node information indicating that the wireless connection is a connection made by the network-controlled repeater. Network controlled repeater.

5. A network node, a transmitter for transmitting control information to the network-controlled repeater for amplifying and relaying a radio signal between the network node and a user equipment by the network-controlled repeater; a receiving unit that receives, when establishing a wireless connection between the network-controlled repeater and the network node, information from the network-controlled repeater indicating that the wireless connection is a connection made by the network-controlled repeater. Network node.

6. 1. A chipset for a network controlled repeater, comprising: receiving control information from a network node; a process of amplifying and relaying a radio signal between the network node and a user equipment by the network-controlled repeater based on the control information; When establishing a wireless connection with the network node, transmitting information to the network node indicating that the wireless connection is a connection made by the network-controlled repeater. Chipset.

7. For network controlled repeaters, receiving control information from a network node; a process of amplifying and relaying a radio signal between the network node and a user equipment by the network-controlled repeater based on the control information; and when establishing a wireless connection with the network node, transmitting information to the network node indicating that the wireless connection is a connection made by the network-controlled repeater. program.

8. A mobile communication system, comprising: A network node; A network-controlled repeater; the network-controlled repeater receiving control information from the network node; The network-controlled repeater amplifies and relays wireless signals between the network node and the user equipment based on the control information; When establishing a wireless connection with the network node, the network-controlled repeater transmits information to the network node indicating that the wireless connection is a connection made by the network-controlled repeater. Mobile communication system.

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