Wireless terminal device, wireless relay device, wireless communication system, and wireless communication method

Abstract

To achieve downsizing and weight saving of a radio relay device.SOLUTION: A radio terminal device includes a calculation part for calculating propagation loss being difference an uplink transmission power value of a signal to be transmitted to a radio relay device by the radio terminal device and an uplink reception signal power value at the radio relay device, calculating power difference being difference between a downlink gain value and propagation loss of the radio relay device, and calculating a downlink reception power prediction value of a signal from a base station of the radio relay device, which is difference between a downlink reception power value of a signal received from the radio relay device by the radio terminal device and the power difference, an antenna control part for outputting beam control information for controlling an antenna beam of a base station side of the radio relay device on the basis of the downlink reception power prediction value, and an uplink information transmission part for transmitting the beam control information to the radio relay device.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a wireless terminal device, a wireless relay device, a wireless communication system, and a wireless communication method. [Background technology]

[0002] Conventionally, there is known a wireless relay device that relays wireless signals between a terminal and a base station. The wireless relay device described in Patent Document 1 demodulates a radio frequency communication signal transmitted within the wireless relay device to obtain a base station ID and a beam ID, and forms a beam on the base station side using an algorithm of the wireless relay device. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Publication No. 2022-096459 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the wireless relay device described in the above-mentioned Patent Document 1 requires a demodulation circuit for signals received from a base station, and because the demodulation circuit is complex and large-scale, it is difficult to reduce the size and weight of the wireless relay device.

[0005] The present invention has been made in consideration of the above circumstances, and an object of the present invention is to reduce the size and weight of a radio repeater device. [Means for solving the problem]

[0006] One aspect of the present invention is a wireless terminal device that transmits and receives signals to and from a base station via a wireless relay device, the wireless terminal device comprising: a downlink information receiving unit that receives from the wireless relay device uplink received signal power information indicating an uplink received signal power value at the wireless relay device in an uplink direction from the wireless terminal device to the base station and downlink gain information indicating a downlink gain value at the wireless relay device in a downlink direction from the base station to the wireless terminal device; a calculation unit that calculates a propagation loss, which is the difference between the uplink transmission power value of a signal that the wireless terminal device transmits to the wireless relay device and the uplink received signal power value, calculates a power difference, which is the difference between the downlink gain value and the propagation loss, and calculates a downlink received power prediction value of a signal from the base station of the wireless relay device, which is the difference between the downlink received power value of a signal that the wireless terminal device receives from the wireless relay device and the power difference; an antenna control unit that outputs beam control information that controls an antenna beam on the base station side of the wireless relay device based on the downlink received power prediction value; and an uplink information transmitting unit that transmits the beam control information to the wireless relay device. One aspect of the present invention is the wireless terminal device, arranged in parallel A plurality of the wireless relay devices individually The wireless terminal device transmits and receives signals to and from one or more of the base stations via the wireless relay device, and generates the beam control information for the multiple wireless relay devices using the same beam control algorithm. One aspect of the present invention is the wireless terminal device, arranged in parallel A plurality of the wireless relay devices individually The wireless terminal device transmits and receives signals to and from one or more of the base stations via the wireless relay device, and generates the beam control information for the wireless relay devices using different beam control algorithms.

[0007] One aspect of the present invention is a wireless relay device that relays signals transmitted and received between a wireless terminal device and a base station, comprising: a downlink information transmission unit that transmits to the wireless terminal device uplink received signal power information indicating an uplink received signal power value at the wireless relay device in the uplink direction from the wireless terminal device to the base station and downlink gain information indicating a downlink gain value at the wireless relay device in the downlink direction from the base station to the wireless terminal device; an uplink information receiving unit that receives beam control information from the wireless terminal device based on the uplink received signal power value and the downlink gain value; and a beam switching unit that switches an antenna beam on the base station side based on the beam control information.

[0008] One aspect of the present invention is a wireless communication system including the wireless terminal device and the wireless relay device.

[0009] One aspect of the present invention is a wireless communication method in which a wireless terminal device transmits and receives signals to and from a base station via a wireless relay device, the method comprising: a downlink information receiving step in which the wireless terminal device receives, from the wireless relay device, uplink received signal power information indicating an uplink received signal power value at the wireless relay device in an uplink direction from the wireless terminal device to the base station, and downlink gain information indicating a downlink gain value at the wireless relay device in a downlink direction from the base station to the wireless terminal device; and a downlink information receiving step in which the wireless terminal device calculates a propagation loss, which is the difference between the uplink transmission power value of a signal transmitted from the wireless terminal device to the wireless relay device and the uplink received signal power value. a calculation step of calculating a downlink gain value, calculating a power difference which is the difference between the downlink gain value and the propagation loss, and calculating a downlink received power prediction value of a signal from the base station of the wireless relay device, which is the difference between the downlink received power value of a signal received by the wireless terminal device from the wireless relay device and the power difference; an antenna control step of the wireless terminal device outputting beam control information to control an antenna beam on the base station side of the wireless relay device based on the downlink received power prediction value; and an uplink information transmission step of the wireless terminal device transmitting the beam control information to the wireless relay device. [Effects of the Invention]

[0010] According to the present invention, it is possible to obtain an effect that the radio relay device can be made smaller and lighter. [Brief explanation of the drawings]

[0011] [Figure 1] 1 is a block diagram illustrating an example of the configuration of a wireless communication system according to an embodiment. [Figure 2] 1 is a block diagram illustrating an example of the configuration of a wireless terminal device and a wireless relay device according to an embodiment. [Figure 3] 1 is a schematic configuration diagram illustrating an example of a wireless communication system according to an embodiment. [Figure 4] FIG. 1 illustrates an example of an embodiment. [Figure 5] FIG. 1 illustrates an example of an embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0012] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Fig. 1 is a block diagram showing an example of the configuration of a wireless communication system according to an embodiment. In the wireless communication system 1 shown in Fig. 1, a wireless terminal device (terminal) UE transmits and receives signals to and from a base station BS via a wireless relay device (repeater) 10. The duplexing method of the wireless communication system 1 may be a TDD (Time Division Duplex) method or an FDD (Frequency Division Duplex) method.

[0013] The base station BS receives an uplink signal (uplink signal) UL from the terminal UE to the base station BS via the repeater 10. The terminal UE receives a downlink signal (downlink signal) DL from the base station BS to the terminal UE via the repeater 10.

[0014] 2 is a block diagram showing an example of the configuration of the terminal UE and the relay 10 according to this embodiment. The terminal UE and the relay 10 according to this embodiment will be described with reference to FIG.

[0015] In FIG. 2, the terminal UE includes an antenna control unit 201, a calculation unit 202, a downlink received signal power detection unit 203, an uplink information transmission unit 204, an uplink transmission unit 205, a downlink reception unit 206, a downlink information reception unit 207, a switch 208, and an antenna 209.

[0016] The repeater 10 includes a switch 251, an uplink received signal power detection unit 252, an uplink information receiving unit 253, an uplink relay unit 254, a downlink relay unit 255, a downlink information transmitting unit 256, a switch 257, a beam switching unit 258, a terminal side antenna 259, and a base station side antenna 260.

[0017] An uplink signal UL is input from an upper layer in the terminal UE to the uplink transmitting unit 205. The uplink signal UL is converted by the uplink transmitting unit 205 into a signal of a frequency used between the terminal UE and the repeater 10, and then wirelessly transmitted from an antenna 209 via a switch 208.

[0018] When the duplexing method is TDD, the selector 208 is a switch that switches the connection of the antenna 209 to either the transmitting circuit of the uplink signal UL or the receiving circuit of the downlink signal DL according to the transmission and reception timing of the uplink signal UL and the downlink signal DL. When the duplexing method is FDD, the selector 208 performs the same operation as the switch in TDD by using a duplexer that can switch the connection of the antenna 209 to either the transmitting circuit of the uplink signal UL or the receiving circuit of the downlink signal DL depending on the frequency, instead of the switch in TDD.

[0019] The radio waves emitted from the antenna 209 are received by the terminal-side antenna 259 of the repeater 10. The uplink signal UL received by the terminal-side antenna 259 is input to the uplink received signal power detection unit 252 via the switch 251, and then subjected to signal amplification and frequency conversion by the uplink repeater unit 254, before being wirelessly transmitted from the base station-side antenna 260 via the switch 257 and the beam switching unit 258. The radio waves emitted from the base station-side antenna 260 are received by the antenna of the base station BS. The base station BS acquires the uplink signal UL received by its own antenna. The switches 251 and 257 switch between uplink and downlink circuits in the same manner as the switch 208 of the terminal UE.

[0020] A downlink signal DL transmitted from the base station BS is received via the base station-side antenna 260 of the repeater 10, input to the downlink repeater 255 via the beam switching unit 258 and the switch 257, where the signal is amplified and frequency converted, and then wirelessly transmitted from the terminal-side antenna 259 via the switch 251. The radio waves radiated from the terminal-side antenna 259 of the repeater 10 are received by the antenna 209 of the terminal UE. The downlink signal DL received by the antenna 209 is output to an upper layer in the terminal UE via the switch 208, the downlink received signal power detection unit 203, and the downlink receiving unit 206.

[0021] The antenna control unit 201 outputs beam control information for controlling the antenna beam B of the base station side antenna 260 of the repeater 10 .

[0022] For example, if the base station side antenna 260 of the repeater 10 is a plurality of antennas that respectively form a plurality of different antenna beams B, the beam control information is an antenna identifier (antenna ID) that identifies the plurality of antennas.

[0023] For example, if the beam switching unit 258 of the repeater 10 has a beamforming function for forming a plurality of different antenna beams B, the beam control information is a beamforming identifier (beamforming ID) for identifying the plurality of different antenna beams B.

[0024] For example, if the beam switching unit 258 of the repeater 10 has a beamforming function for forming an arbitrary antenna beam B, the beam control information is information on the phase and amplitude of the antenna element for forming the antenna beam B (antenna element phase and amplitude information).

[0025] The beam control information output from the antenna control unit 201 is wirelessly transmitted from the antenna 209 via the uplink information transmission unit 204, the uplink transmission unit 205, and the switch 208. The beam control information wirelessly transmitted from the antenna 209 is received via the terminal-side antenna 259 of the repeater 10. The beam control information received via the terminal-side antenna 259 of the repeater 10 is input to the beam switching unit 258 via the switch 251, the uplink received signal power detection unit 252, the uplink repeater 254, and the uplink information receiving unit 253. The beam switching unit 258 switches the antenna beam of the base station-side antenna 260 based on the beam control information.

[0026] For example, if the base station side antenna 260 of the repeater 10 is a plurality of antennas each forming a plurality of different antenna beams B, the beam switching unit 258 switches to the antenna corresponding to the antenna ID in the beam control information. This switches to the antenna beam B of the antenna corresponding to the antenna ID in the beam control information.

[0027] For example, if the beam switching unit 258 of the repeater 10 has a beam forming function for forming a plurality of different antenna beams B, the beam switching unit 258 forms the antenna beam B corresponding to the beam forming ID in the beam control information by the beam forming function, thereby switching to the antenna beam B corresponding to the beam forming ID in the beam control information.

[0028] For example, if the beam switching unit 258 of the repeater 10 has a beam forming function for forming an arbitrary antenna beam B, the beam switching unit 258 forms the antenna beam B by the beam forming function based on the antenna element phase and amplitude information of the beam control information. This switches to the antenna beam B corresponding to the antenna element phase and amplitude information of the beam control information.

[0029] The beam control information may be transmitted from the uplink information transmitter 204 of the terminal UE to the uplink information receiver 253 of the repeater 10, and the transmission method is not limited thereto. For example, the beam control information may be wirelessly transmitted from the terminal UE to the repeater 10 by utilizing a guard band in the band of the radio transmission channel of the uplink signal UL in the radio communication system 1. For example, the beam control information may be wirelessly transmitted from the terminal UE to the repeater 10 by short-range radio communication between the terminal UE and the repeater 10. For example, "Bluetooth (registered trademark)" or "Wi-Fi (registered trademark)" may be used as the short-range radio communication method.

[0030] The downlink information transmission unit 256 acquires uplink received signal power information indicating the uplink received signal power value at the uplink repeater 10 from the uplink received signal power detection unit 252. The downlink information transmission unit 256 acquires downlink gain information indicating the downlink gain value at the downlink repeater 10 from the downlink relay unit 255. The downlink information transmission unit 256 outputs the uplink received signal power information acquired from the uplink received signal power detection unit 252 and the downlink gain information acquired from the downlink relay unit 255.

[0031] The uplink received signal power information and downlink gain information output from the downlink information transmission unit 256 are wirelessly transmitted from the terminal side antenna 259 via the downlink repeater 255 and the switch 251. The uplink received signal power information and downlink gain information wirelessly transmitted from the terminal side antenna 259 are received via the antenna 209 of the terminal UE. The uplink received signal power information and downlink gain information received via the antenna 209 of the terminal UE are input to the calculation unit 202 via the switch 208, the downlink received signal power detection unit 203, the downlink receiving unit 206 and the downlink information receiving unit 207.

[0032] The uplink received signal power information and downlink gain information may be transmitted from the downlink information transmission unit 256 of the repeater 10 to the downlink information reception unit 207 of the terminal UE by any transmission method, and the transmission method is not limited thereto. For example, the uplink received signal power information and downlink gain information may be transmitted wirelessly from the repeater 10 to the terminal UE by utilizing a guard band of the band of the radio transmission channel of the downlink signal DL in the radio communication system 1. For example, the uplink received signal power information and downlink gain information may be transmitted wirelessly from the repeater 10 to the terminal UE by short-range radio communication between the repeater 10 and the terminal UE.

[0033] The downlink received signal power detection unit 203 detects the downlink received power value of the signal that the terminal UE receives from the repeater 10. The downlink received power value may be the received power value of the signal that the terminal UE receives from the repeater 10, or may be the level of a signal (for example, a pilot signal) that the terminal UE detects by demodulating the received signal that it receives from the repeater 10. The downlink received signal power detection unit 203 outputs the downlink received power value to the calculation unit 202.

[0034] The calculation unit 202 acquires an uplink transmission power value of an uplink signal UL that the terminal UE transmits to the repeater 10. The uplink transmission power value is set in advance in the terminal UE, or is sequentially set to a value determined by the uplink transmission unit 205 by a transmission power control function or the like according to the communication method.

[0035] The calculation unit 202 calculates the propagation loss, which is the difference between the uplink transmission power value of the terminal UE and the uplink received signal power value of the repeater 10 indicated in the uplink received signal power information, using the following equation. "Propagation loss" = "Uplink transmission power value" - "Uplink received signal power value"

[0036] Next, the calculation unit 202 calculates a power difference, which is the difference between the downstream gain value of the repeater 10 indicated in the downstream gain information and the calculated propagation loss, using the following equation. "Power difference" = "Downlink gain value" - "Path loss" The power difference indicates the difference in the received power value of the downlink received signal between the terminal UE and the repeater 10. Alternatively, the power difference indicates the difference in the level of a signal (e.g., a pilot signal) detected by demodulating the downlink received signal between the terminal UE and the repeater 10.

[0037] Next, the calculation unit 202 calculates the predicted downlink reception power value of the downlink signal DL from the base station BS of the repeater 10, which is the difference between the downlink reception power value of the terminal UE and the calculated power difference, using the following equation. "Predicted downlink received power value of repeater" = "Downlink received power value of terminal" - "Power difference" The downlink reception power prediction value is a prediction value of the reception power value of the downlink signal DL received by the repeater 10 from the base station BS, or a prediction value of the level of a signal (e.g., a pilot signal) detected by demodulating the downlink signal DL received by the repeater 10 from the base station BS.

[0038] The calculation unit 202 outputs the calculated predicted value of the downlink reception power of the repeater 10 to the antenna control unit 201 .

[0039] The antenna control unit 201 outputs beam control information for controlling the antenna beam of the base station side antenna 260 of the repeater 10 to the uplink information transmission unit 204 based on the predicted downlink received power value of the repeater 10. The algorithm by which the antenna control unit 201 generates the beam control information may use a beam control algorithm in an existing terminal.

[0040] Fig. 3 is a schematic diagram showing an example of a wireless communication system 1 according to this embodiment. In the wireless communication system 1 shown in Fig. 3, the radio frequency used on the base station side is different from the radio frequency used on the terminal side. The radio frequency used on the base station side is in the millimeter wave band. The radio frequency used on the terminal side is in the terahertz band.

[0041] In the wireless communication system 1 shown in FIG. 3, the repeater 10 according to this embodiment can be mounted in various devices DVa, DVb, DVc, DVd, and DVe. Device DVa is glasses worn by a user (terminal user) of the terminal UE. Device DVb is a vehicle in which the terminal user rides. Device DVc is headphones worn by the terminal user. Device DVd is a wristwatch worn by the terminal user. Device DVe is a portable personal computer (PC) used by the terminal user.

[0042] The repeater 10 is provided, for example, in glasses (device DVa) worn by the terminal user. The terminal UE includes an antenna 301 (corresponding to antenna 209 in FIG. 2) for transmitting and receiving wireless signals in the terahertz band, and a signal processing unit 302 for processing received signals in the terahertz band. The signal processing unit 302 demodulates a downlink signal DL in the terahertz band received by the antenna 301 via the repeater 10 provided in the glasses (device DVa). The signal processing unit 302 also transmits an uplink signal UL in the terahertz band from the antenna 301.

[0043] A terahertz band link THzLINK is established between the terminal UE and a repeater 10 provided in the glasses (device DVa). The repeater 10 provided in the glasses (device DVa) transmits and receives millimeter wave band uplink signals UL and downlink signals DL to and from the base station BS. The repeater 10 provided in the glasses (device DVa) receives the uplink signals UL and downlink signals DL, respectively, converts their frequencies, amplifies them, and then transmits them. This allows the terminal UE and base station BS to communicate bidirectionally via the repeater 10 provided in the glasses (device DVa).

[0044] Here, for example, small devices such as glasses (device DVa), headphones (device DVc), and wristwatches (device DVd) are subject to significant constraints in terms of the size, weight, battery capacity, and other factors that can be accommodated in the devices. Therefore, for these small devices DVa, DVc, and DVd, the repeater 10 to be installed must be particularly small, lightweight, and power-efficient. This embodiment provides particularly significant benefits when the repeater 10 is installed in such small devices DVa, DVc, and DVd. The wireless communication system 1 shown in FIG. 3 can be applied to future 6G and Beyond 5G, for example.

[0045] 4 and 5 are diagrams showing examples of this embodiment. The examples shown in Fig. 4 and 5 are examples in which a terminal UE transmits and receives signals to and from one or more base stations BS via multiple repeaters 10.

[0046] In the embodiment of Fig. 4, the terminal UE generates beam control information using the same beam control algorithm for multiple repeaters 10. In the example of Fig. 4, the terminal UE generates beam control information for two repeaters 10-1 and 10-2 mounted on glasses (device DVa) so as to direct antenna beam B of base station side antenna 260 toward the same base station BS-1. This beam control information causes each repeater 10-1 and 10-2 to direct antenna beam B of base station side antenna 260 toward the same base station BS-1.

[0047] In the embodiment of Fig. 5, the terminal UE generates beam control information using different beam control algorithms for each of the multiple repeaters 10. In the example of Fig. 5, the terminal UE generates beam control information for the repeater 10-1 of the two repeaters 10-1 and 10-2 mounted on the glasses (device DVa) so that the repeater 10-1 directs the antenna beam B of the base station side antenna 260 to base station BS-1, and generates beam control information for the repeater 10-2 so that the antenna beam B of the base station side antenna 260 to base station BS-2. By using the beam control information, the repeater 10-1 directs the antenna beam B of the base station side antenna 260 to base station BS-1, while Repeater 10-1 directs antenna beam B of base station side antenna 260 toward base station BS-2.

[0048] The terminal UE may generate beam control information so that a plurality of relays 10 cooperate to form an optimal antenna beam.

[0049] As described above, according to this embodiment, it is possible to obtain the effect of reducing the size and weight of the wireless relay device.

[0050] This will enable improvements in the overall service quality of wireless communication systems, for example, and contribute to Goal 9 of the United Nations' Sustainable Development Goals (SDGs), which is to "Build resilient infrastructure, promote sustainable industrialization and foster innovation."

[0051] Although an embodiment of the present invention has been described in detail above with reference to the drawings, the specific configuration is not limited to this embodiment, and design changes and the like are also included within the scope that does not deviate from the gist of the present invention.

[0052] In addition, a computer program for realizing the functions of each of the above-described devices may be recorded on a computer-readable recording medium, and the program recorded on the recording medium may be read and executed by a computer system. Note that the "computer system" here may also include hardware such as an OS and peripheral devices. In addition, "computer-readable recording medium" refers to writable non-volatile memory such as a flexible disk, optical magnetic disk, ROM, or flash memory, portable media such as a DVD (Digital Versatile Disc), or a storage device such as a hard disk built into a computer system.

[0053] Furthermore, the term "computer-readable recording medium" also includes those that retain a program for a certain period of time, such as volatile memory (e.g., DRAM (Dynamic Random Access Memory)) within a computer system that serves as a server or client when a program is transmitted via a network such as the Internet or a communication line such as a telephone line. The program may be transmitted from a computer system storing the program in a storage device or the like to another computer system via a transmission medium or by transmission waves in the transmission medium. Here, the "transmission medium" that transmits the program refers to a medium that has the function of transmitting information, such as a network (communication network) such as the Internet or a communication line (communication line) such as a telephone line. The program may also be a program for implementing some of the functions described above, or may be a so-called differential file (differential program) that can implement the functions described above in combination with a program already stored in the computer system. [Explanation of symbols]

[0054] 1...wireless communication system, UE...wireless terminal device, BS...base station, 10...wireless relay device, 201...antenna control unit, 202...calculation unit, 203...downlink received signal power detection unit, 204...uplink information transmission unit, 205...uplink transmission unit, 206...downlink reception unit, 207...downlink information reception unit, 208...switch, 209...antenna, 251...switch, 252...uplink received signal power detection unit, 253...uplink information reception unit, 254...uplink relay unit, 255...downlink relay unit, 256...downlink information transmission unit, 257...switch, 258...beam switching unit, 259...terminal side antenna, 260...base station side antenna

Claims

1. In a wireless terminal device that transmits and receives signals to and from a base station via a wireless relay device, a downlink information receiving unit that receives, from the wireless relay device, uplink received signal power information indicating an uplink received signal power value at the wireless relay device in an uplink direction from the wireless terminal device to the base station, and downlink gain information indicating a downlink gain value at the wireless relay device in a downlink direction from the base station to the wireless terminal device; a calculation unit that calculates a propagation loss, which is a difference between an uplink transmission power value of a signal transmitted from the wireless terminal device to the wireless relay device and a power value of the uplink received signal, calculates a power difference, which is a difference between the downlink gain value and the propagation loss, and calculates a downlink received power prediction value of a signal from the base station of the wireless relay device, which is a difference between the downlink received power value of a signal received by the wireless terminal device from the wireless relay device and the power difference; an antenna control unit that outputs beam control information for controlling an antenna beam on the side of the base station of the radio relay device based on the downlink received power prediction value; an uplink information transmission unit that transmits the beam control information to the radio relay device; A wireless terminal device comprising:

2. the wireless terminal device transmits and receives signals to and from one or more of the base stations via the plurality of wireless relay devices arranged in parallel, and generates the beam control information for the plurality of wireless relay devices using the same beam control algorithm; 2. The wireless terminal device according to claim 1.

3. the wireless terminal device transmits and receives signals to and from one or more of the base stations via the plurality of wireless relay devices arranged in parallel, and generates the beam control information for the plurality of wireless relay devices using different beam control algorithms, respectively; 2. The wireless terminal device according to claim 1.

4. In a wireless relay device that relays signals transmitted and received between a wireless terminal device and a base station, a downlink information transmitting unit configured to transmit, to the wireless terminal device, uplink received signal power information indicating an uplink received signal power value at the wireless relay device in an uplink direction from the wireless terminal device to the base station, and downlink gain information indicating a downlink gain value at the wireless relay device in a downlink direction from the base station to the wireless terminal device; an uplink information receiving unit that receives beam control information based on the uplink received signal power value and the downlink gain value from the wireless terminal device; a beam switching unit that switches an antenna beam on the side of the base station based on the beam control information; A wireless relay device comprising:

5. A wireless terminal device according to claim 1, a wireless relay device according to claim 4, A wireless communication system comprising:

6. A wireless communication method in which a wireless terminal device transmits and receives signals to and from a base station via a wireless relay device, comprising: a downlink information receiving step in which the wireless terminal device receives, from the wireless relay device, uplink received signal power information indicating an uplink received signal power value at the wireless relay device in an uplink direction from the wireless terminal device to the base station, and downlink gain information indicating a downlink gain value at the wireless relay device in a downlink direction from the base station to the wireless terminal device; a calculation step in which the wireless terminal device calculates a propagation loss, which is the difference between an uplink transmission power value of a signal transmitted from the wireless terminal device to the wireless relay device and a power value of the uplink received signal, calculates a power difference, which is the difference between the downlink gain value and the propagation loss, and calculates a downlink received power prediction value of the signal from the base station of the wireless relay device, which is the difference between the downlink received power value of the signal received by the wireless terminal device from the wireless relay device and the power difference; an antenna control step in which the wireless terminal device outputs beam control information for controlling an antenna beam of the base station side of the wireless relay device based on the downlink received power prediction value; an uplink information transmission step in which the wireless terminal device transmits the beam control information to the wireless relay device; A wireless communication method comprising:

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