JP7763205B2 - Wireless terminal device, wireless relay device, wireless communication system, and wireless communication method - Google Patents

Description

The present invention relates to a wireless terminal device, a wireless relay device, a wireless communication system, and a wireless communication method.

Conventionally, wireless relay devices that relay wireless signals between terminals and base stations are known. The wireless relay device described in Patent Document 1 demodulates radio frequency communication signals transmitted within the wireless relay device to obtain base station IDs and beam IDs, and forms beams on the base station side using the wireless relay device's algorithm.

Japanese Patent Application Laid-Open No. 2022-096459

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

The present invention was made in consideration of these circumstances, and its purpose is to make wireless relay devices smaller and lighter.

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 a wireless terminal device in which, in the above-mentioned wireless terminal device, the wireless terminal device transmits and receives signals to and from one or more base stations via each of multiple wireless relay devices arranged in parallel , 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 a wireless terminal device in which, in the above-mentioned wireless terminal device, the wireless terminal device transmits and receives signals to and from one or more base stations via each of multiple wireless relay devices arranged in parallel , and generates the beam control information for each of the multiple wireless relay devices using a different beam control algorithm.

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 transmitter that transmits to the wireless terminal device uplink received signal power information indicating the 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 the downlink gain value at the wireless relay device in the downlink direction from the base station to the wireless terminal device; an uplink information receiver 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 the antenna beam on the base station side based on the beam control information.

One aspect of the present invention is a wireless communication system comprising the above-described wireless terminal device and the above-described wireless relay device.

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, comprising a downlink information receiving step in which the wireless terminal device receives from the wireless relay device uplink received signal power information indicating the 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 the downlink gain value at the wireless relay device in the 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. This wireless communication method includes 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 reception power prediction value of the signal from the base station of the wireless relay device, which is the difference between the downlink reception 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 to control the antenna beam of the base station side of the wireless relay device based on the downlink reception power prediction value; and an uplink information transmission step in which the wireless terminal device transmits the beam control information to the wireless relay device.

The present invention has the effect of enabling wireless relay devices to be made smaller and lighter.

1 is a block diagram illustrating an example of the configuration of a wireless communication system according to an embodiment. 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. 1 is a schematic configuration diagram illustrating an example of a wireless communication system according to an embodiment. FIG. 1 illustrates an example of an embodiment. FIG. 1 illustrates an example of an embodiment.

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.

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.

Figure 2 is a block diagram showing an example configuration of a terminal UE and a repeater 10 according to this embodiment. The terminal UE and the repeater 10 according to this embodiment will be described with reference to Figure 2.

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.

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.

Uplink signal UL is input to uplink transmitter 205 from a higher layer in the terminal UE. The uplink signal UL is converted by uplink transmitter 205 into a signal of the frequency used between the terminal UE and repeater 10, and then wirelessly transmitted from antenna 209 via switch 208.

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

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.

The downlink signal DL transmitted from the base station BS is received via the base station-side antenna 260 of the repeater 10, and input to the downlink repeater 255 via the beam switching unit 258 and the switch 257, where it 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 the upper layer in the terminal UE via the switch 208, the downlink received signal power detection unit 203, and the downlink receiving unit 206.

The antenna control unit 201 outputs beam control information that controls antenna beam B of the base station side antenna 260 of the repeater 10.

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

For example, if the beam switching unit 258 of the repeater 10 has a beamforming function that forms multiple different antenna beams B, the beam control information is a beamforming identifier (beamforming ID) that identifies the multiple different antenna beams B.

For example, if the beam switching unit 258 of the repeater 10 has a beamforming function that forms 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).

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.

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.

For example, if the beam switching unit 258 of the repeater 10 has a beam forming function that forms multiple different antenna beams B, the beam switching unit 258 uses the beam forming function to form the antenna beam B corresponding to the beam forming ID in the beam control information. This switches to the antenna beam B corresponding to the beam forming ID in the beam control information.

For example, if the beam switching unit 258 of the repeater 10 has a beamforming function that forms an arbitrary antenna beam B, the beam switching unit 258 forms the antenna beam B using the beamforming function based on the antenna element phase and amplitude information in the beam control information. This switches to the antenna beam B that corresponds to the antenna element phase and amplitude information in the beam control information.

The beam control information may be transmitted from the uplink information transmission unit 204 of the terminal UE to the uplink information reception unit 253 of the repeater 10 by any suitable transmission method. For example, the beam control information may be transmitted wirelessly from the terminal UE to the repeater 10 by utilizing a guard band in the bandwidth of the wireless transmission channel of the uplink signal UL in the wireless communication system 1. For example, the beam control information may be transmitted wirelessly from the terminal UE to the repeater 10 by short-range wireless 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 wireless communication method.

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.

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 relay unit 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.

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 suitable transmission method. For example, the uplink received signal power information and downlink gain information may be wirelessly transmitted from the repeater 10 to the terminal UE by utilizing a guard band in the bandwidth of the wireless transmission channel for the downlink signal DL in the wireless communication system 1. For example, the uplink received signal power information and downlink gain information may be wirelessly transmitted from the repeater 10 to the terminal UE by short-range wireless communication between the repeater 10 and the terminal UE.

The downlink received signal power detection unit 203 detects the downlink received power value of the signal received by the terminal UE from the repeater 10. The downlink received power value may be the received power value of the signal received by the terminal UE from the repeater 10, or it may be the level of a signal (e.g., a pilot signal) detected by demodulating the signal received by the terminal UE from the repeater 10. The downlink received signal power detection unit 203 outputs the downlink received power value to the calculation unit 202.

The calculation unit 202 obtains the uplink transmission power value of the uplink signal UL transmitted by the terminal UE to the repeater 10. The uplink transmission power value is either set in advance in the terminal UE or is sequentially set to a value determined by the uplink transmission unit 205 using a transmission power control function or the like according to the communication method.

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 reception signal power value of the repeater 10 indicated in the uplink reception signal power information, using the following equation.
"Propagation loss" = "Uplink transmission power value" - "Uplink received signal power value"

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" - "Propagation loss"
The power difference indicates a difference in the received power value of the downlink received signal between the terminal UE and the repeater 10. Alternatively, the power difference indicates a 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.

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.

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

The antenna control unit 201 outputs beam control information to the uplink information transmission unit 204 to control the antenna beam of the base station side antenna 260 of the repeater 10 based on the predicted downlink reception power value of the repeater 10. The algorithm used by the antenna control unit 201 to generate the beam control information may be the same as the beam control algorithm used in existing terminals.

Figure 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 Figure 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.

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

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 terahertz band radio signals, and a signal processing unit 302 for processing received terahertz band signals. The signal processing unit 302 demodulates terahertz band downlink signals DL received by antenna 301 via the repeater 10 provided in the glasses (device DVa). The signal processing unit 302 also transmits terahertz band uplink signals UL via antenna 301.

A terahertz band link THzLINK is established between the terminal UE and the 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 with 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).

Here, for example, small devices such as glasses (device DVa), headphones (device DVc), and wristwatches (device DVd) are subject to significant constraints regarding the size, weight, battery capacity, and other factors that can be accommodated. Therefore, for these small devices DVa, DVc, and DVd, the repeater 10 installed therein must be particularly compact, lightweight, and energy-efficient. This embodiment achieves 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.

Figures 4 and 5 are diagrams showing examples of this embodiment. The examples shown in Figures 4 and 5 show a case where a terminal UE transmits and receives signals to and from one or more base stations BS via multiple repeaters 10.

In the embodiment of FIG. 4, the terminal UE generates beam control information for multiple repeaters 10 using the same beam control algorithm. 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 that they direct antenna beam B of the 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 the base station side antenna 260 toward the same base station BS-1.

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 repeater 10-2 directs 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
The repeater 10-1 directs the antenna beam B of the base station side antenna 260 toward the base station BS-2.

The terminal UE may generate beam control information so that multiple repeaters 10 work together to form the optimal antenna beam.

As described above, this embodiment has the advantage of enabling wireless relay devices to be made smaller and lighter.

This will enable improvements in overall service quality in 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."

The above describes in detail an embodiment of the present invention with reference to the drawings, but the specific configuration is not limited to this embodiment and includes design modifications and the like that do not deviate from the gist of the present invention.

Furthermore, a computer program for implementing 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 term "computer system" may 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 storage devices such as a hard disk built into a computer system.

Furthermore, "computer-readable recording medium" also includes a device that stores 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.

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 (6)

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