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

Abstract

To easily determine the antenna beam of a wireless relay device.SOLUTION: A wireless relay device receives notification of terminal beam information from a wireless terminal indicating the directional direction of the wireless terminal's antenna beam to be directed toward a base station, which has been determined between the wireless terminal and the base station, and determines the wireless relay device's antenna beam to be directed toward the base station on the basis of the directional direction indicated in the terminal beam information notified from the wireless terminal.SELECTED DRAWING: Figure 3

Description

[Technical Field]

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

[0002] Conventionally, a wireless relay device that relays wireless signals between a wireless terminal and a base station has been known (see, for example, Patent Document 1). In the technology described in Patent Document 1, the base station determines, through measurements, the antenna beam (antenna beam) that the base station uses to transmit and receive wireless signals to and from the wireless relay device, and the antenna beam that the wireless relay device uses to transmit and receive wireless signals to and from the wireless terminal. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2023-36366 Summary of the Invention [Problem to be solved by the invention]

[0004] The technology described in the above-mentioned Patent Document 1 selects the best antenna beam combination from among "i x j x k" combinations of antenna beams, consisting of i antenna beams from the base station, j antenna beams from the wireless relay device to the wireless terminal, and k antenna beams from the wireless terminal to the wireless relay device, based on the results of measuring all combinations of antenna beams. Since measuring all combinations of antenna beams takes time, there is a possibility that the user carrying the wireless terminal may move during the measurement. If the user carrying the wireless terminal moves during the measurement, changing the orientation of the antennas of the wireless terminal and the wireless relay device, it becomes difficult to select the best antenna beam combination.

[0005] The present invention has been made in consideration of the above circumstances, and an object of the present invention is to make it possible to easily determine an antenna beam for a radio relay device. [Means for solving the problem]

[0006] One aspect of the present invention is a wireless system comprising a wireless relay device that relays signals transmitted and received between a base station and a wireless terminal, and the wireless terminal that transmits and receives signals to and from the base station via the wireless relay device, wherein the wireless terminal is provided with a terminal control unit that notifies the wireless relay device of terminal beam information indicating the directional direction of the antenna beam of the wireless terminal that the wireless terminal will point towards the base station, as determined between the wireless terminal and the base station, and the wireless relay device is provided with a relay device control unit that determines the antenna beam of the wireless relay device that the wireless relay device will point towards the base station, based on the directional direction indicated in the terminal beam information notified by the wireless terminal. One aspect of the present invention is a wireless system in which, in the above-mentioned wireless system, the terminal beam information includes a rotation angle of the wireless terminal relative to a reference orientation of the wireless terminal and the wireless relay device, and information representing the directional direction of the antenna beam of the wireless terminal directed toward the base station, as determined between the wireless terminal and the base station, in terms of a direction relative to the reference orientation. One aspect of the present invention is a wireless system in which, in the above-mentioned wireless system, the terminal beam information includes information representing, in azimuth, the directional direction of the antenna beam of the wireless terminal that is directed toward the base station, as determined between the wireless terminal and the base station. One aspect of the present invention is a wireless system in which, in the above-mentioned wireless system, multiple wireless relay devices are provided for one of the wireless terminals, and the multiple wireless relay devices each determine the antenna beam of the wireless relay device using the common terminal beam information notified by the one of the wireless terminals.

[0007] One aspect of the present invention is a wireless relay device that relays signals transmitted and received between a base station and a wireless terminal, and includes a relay device control unit that receives, from the wireless terminal, terminal beam information indicating the directional direction of the wireless terminal's antenna beam to be directed toward the base station, which has been determined between the wireless terminal and the base station, and determines the wireless relay device's antenna beam to be directed toward the base station based on the directional direction indicated in the terminal beam information notified from the wireless terminal.

[0008] One aspect of the present invention is a wireless terminal that transmits and receives signals to and from a base station via a wireless relay device, and that includes a terminal control unit that notifies the wireless relay device of terminal beam information that indicates the directional direction of the antenna beam of the wireless terminal that is directed toward the base station, as determined between the wireless terminal and the base station.

[0009] One aspect of the present invention is a wireless relay method comprising: a wireless relay device that relays signals transmitted and received between a base station and a wireless terminal; and the wireless terminal that transmits and receives signals to and from the base station via the wireless relay device, wherein the wireless terminal notifies the wireless relay device of terminal beam information indicating the directional direction of the antenna beam of the wireless terminal that the wireless terminal will point toward the base station, which has been determined between the wireless terminal and the base station; and the wireless relay device determines the antenna beam of the wireless relay device that the wireless relay device will point toward the base station based on the directional direction indicated in the terminal beam information notified by the wireless terminal. [Effects of the Invention]

[0010] According to the present invention, it is possible to obtain an effect that the antenna beam of the radio relay device can be easily determined. [Brief explanation of the drawings]

[0011] [Figure 1] FIG. 1 is a diagram illustrating an example of the configuration of a wireless system according to an embodiment. [Figure 2] FIG. 2 is a diagram illustrating an antenna beam in a wireless system according to an embodiment. [Figure 3] FIG. 2 is a diagram illustrating an example of the configuration of a repeater according to an embodiment. [Figure 4] FIG. 2 is a diagram illustrating a configuration example of a terminal according to an embodiment. [Figure 5] FIG. 10 is a sequence diagram illustrating an example of a procedure of a wireless relay method according to an embodiment. [Figure 6] FIG. 10 is an explanatory diagram of a beam selection phase between a base station and a repeater according to one embodiment. [Figure 7] FIG. 10 is an explanatory diagram of a beam selection phase between a base station and a repeater according to one embodiment. [Figure 8] FIG. 10 is an explanatory diagram of a reference direction axis and a reference orientation according to an embodiment. [Figure 9] FIG. 10 is an explanatory diagram of a reference direction axis and a reference orientation according to an embodiment. [Figure 10] 10 is a flowchart illustrating an example of a procedure for a beam determination method for a base station of a repeater according to an embodiment. [Figure 11] A figure showing an example of the correspondence between a beam ID for a base station and a direction of a terminal according to one embodiment. [Figure 12] A figure showing an example of the correspondence between the beam ID for the base station and the direction of direction of the repeater in one 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 diagram showing an example of the configuration of a wireless system according to an embodiment. In FIG. 1, the wireless system 1 includes a wireless terminal (terminal) UE and wireless relay devices (repeaters) 10 (10-1, 10-2, 10-3, 10-4). There may be one or more repeaters 10. The repeater 10 relays signals transmitted and received between a base station BS and the terminal UE. A user U carries and uses the terminal UE.

[0013] The repeaters 10 (10-1, 10-2, 10-3, 10-4) can be installed in various devices DVa, DVb, DVc, DVd, and DVe. In the example of FIG. 1, the device DVa is glasses worn by the user U. The device DVb is a belt worn by the user U. The device DVc is headphones worn by the user U. The device DVd is a wristwatch worn by the user U.

[0014] A terminal UE transmits and receives signals to and from a base station BS via one or more repeaters 10. In the wireless system 1 of FIG. 1, 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 (for example, 28 GHz band or 39 GHz band). The radio frequency used on the terminal side is in the terahertz band (for example, 250 GHz to 300 GHz). This wireless system 1 can be applied to improve uplink communication speeds in mobile communication systems such as Beyond 5G and 6G.

[0015] Since the millimeter wave and terahertz bands have a larger propagation loss over distance than Sub-6 (less than 6 GHz), antennas with high gain and narrow beam widths are often used for the millimeter wave and terahertz bands. For this reason, it is preferable that the antenna beam direction of both the transmitting and receiving stations in the millimeter wave and terahertz bands be directed toward the opposite station.

[0016] 2 is a diagram showing antenna beams in the wireless system according to this embodiment. The terminal UE has an antenna beam Bm_UE1 directed toward the repeater 10 and an antenna beam Bm_UE2 directed toward the base station BS. The repeater 10 has an antenna beam Bm_RS1 directed toward the terminal UE and an antenna beam Bm_RS2 directed toward the base station BS. The base station BS has an antenna beam Bm_BS1.

[0017] There are i types of antenna beams that the terminal UE can form as the antenna beam Bm_UE1 directed towards the repeater 10. There are k2 types of antenna beams that the terminal UE can form as the antenna beam Bm_UE2 directed towards the base station BS. There are j types of antenna beams that the repeater 10 can form as the antenna beam Bm_RS1 directed towards the terminal UE. There are k1 types of antenna beams that the repeater 10 can form as the antenna beam Bm_RS2 directed towards the base station BS. There are l types of antenna beams that the base station BS can form as the antenna beam Bm_BS1.

[0018] In this embodiment, since the user U moves around carrying the terminal UE and the repeater 10, the orientation of the direction of the antenna beams of the terminal UE and the repeater 10 may change. For this reason, in the wireless system 1, it is preferable that the antenna beam Bm_UE1, the antenna beam Bm_RS1, the antenna beam Bm_RS2, and the antenna beam Bm_BS1 are dynamically determined so that the direction of the antenna beams faces each other between the base station BS and the repeater 10 and between the repeater 10 and the terminal UE. In view of this situation, this embodiment aims to enable the repeater 10 to easily determine the antenna beam to be used for transmitting and receiving radio signals to and from the terminal UE.

[0019] 3 is a diagram showing an example of the configuration of a repeater according to this embodiment. In FIG. 3, repeater 10 includes wireless communication unit 110, relay communication unit 120, storage unit 130, and control unit 140 (relay device control unit). Relay communication unit 120 includes terminal-side communication unit 121 and base station-side communication unit 122.

[0020] The wireless communication unit 110 transmits and receives signals to and from the terminal UE by short-range wireless communication such as "Bluetooth (registered trademark)."

[0021] The relay communication unit 120 performs communication to relay signals transmitted and received between the terminal UE and the base station BS. The terminal-side communication unit 121 transmits and receives signals to and from the terminal UE using the antenna beam Bm_RS1. The base station-side communication unit 122 transmits and receives signals to and from the base station BS using the antenna beam Bm_RS2.

[0022] The storage unit 130 includes a storage medium such as a ROM (Read Only Memory), a RAM (Random Access Memory), or an SSD (Solid State Drive). The storage unit 130 stores programs and various data executed by the control unit 140. The control unit 140 includes, for example, a CPU (Central Processing Unit), and realizes its functions by executing the programs stored in the storage unit 130.

[0023] The control unit 140 controls the repeater 10. The control unit 140 controls relaying of signals transmitted and received between the terminal UE and the base station BS. The control unit 140 controls the antenna beams Bm_RS1 and Bm_RS2.

[0024] The control unit 140 selects an antenna beam Bm_RS1 to be used for transmitting and receiving signals to and from the terminal UE from among j antenna beams that can be formed as an antenna beam Bm_RS1 to be directed toward the terminal UE. The control unit 140 selects an antenna beam Bm_RS2 to be used for transmitting and receiving signals to and from the base station BS from among k1 antenna beams that can be formed as an antenna beam Bm_RS2 to be directed toward the base station BS.

[0025] Fig. 4 is a diagram showing an example of the configuration of a terminal according to this embodiment. In Fig. 4, the terminal UE includes a radio communication unit 210, a base station side communication unit 220, a repeater side communication unit 230, a storage unit 240, and a control unit 250 (terminal control unit).

[0026] The wireless communication unit 210 transmits and receives signals to and from the repeater 10 using a wireless communication method compatible with the wireless communication unit 110 of the repeater 10. The wireless communication unit 210 transmits and receives signals to and from the repeater 10 using short-range wireless communication such as Bluetooth (registered trademark).

[0027] The base station side communication unit 220 transmits and receives signals to and from the base station BS using the antenna beam Bm_UE2. The repeater side communication unit 230 transmits and receives signals to and from the repeater 10 using the antenna beam Bm_UE1.

[0028] The storage unit 240 includes a storage medium such as a ROM, a RAM, or an SSD. The storage unit 240 stores various data and programs executed by the control unit 250. The control unit 250 includes a CPU, for example, and executes the programs stored in the storage unit 240 to realize its functions.

[0029] The control unit 250 controls the terminal UE. The control unit 250 transmits and receives signals to and from the base station BS via the repeater 10 using the repeater-side communication unit 230. The control unit 250 controls the antenna beam Bm_UE1 and the antenna beam Bm_UE2.

[0030] The control unit 250 selects an antenna beam Bm_UE1 to be used for transmitting and receiving signals to and from the repeater 10 from among the i antenna beams that can be formed as the antenna beam Bm_UE1 to be directed toward the repeater 10. The control unit 250 selects an antenna beam Bm_UE2 to be used for transmitting and receiving signals to and from the base station BS from among the k2 antenna beams that can be formed as the antenna beam Bm_UE2 to be directed toward the base station BS.

[0031] Fig. 5 is a sequence diagram showing an example of the procedure of the wireless relay method according to this embodiment. As shown in Fig. 5, in this embodiment, the selection of the antenna beam to be used for wireless relay between the terminal UE and the base station BS is performed in two separate phases: a beam selection phase between the base station BS and the repeater 10, and a beam selection phase between each repeater 10 and the terminal UE.

[0032] [Beam selection phase between base station BS and repeater 10] We will now explain the beam selection phase between the base station BS and the repeater 10. In the beam selection phase between the base station BS and the repeater 10, the beam selection function between the base station BS and the terminal UE selects a combination of the terminal UE and base station BS antenna beams Bm_UE2 and Bm_BS1 from among "k2 x l" combinations, and based on the direction of the selected terminal UE antenna beam Bm_UE2, the repeater 10 selects the antenna beam Bm_UE2 to be directed toward the base station BS from among k1 combinations.

[0033] 6 and 7 are explanatory diagrams of the beam selection phase between the base station BS and the repeater 10. The terminal UE carried by the user U and the repeater 10 are in close proximity. With respect to the terminal UE and the repeater 10 that are in close proximity, the direction DIR_UE from the terminal UE to the base station BS and the direction DIR_RS from the repeater 10 to the base station BS can be considered to be the same direction. This also applies to the reverse direction.

[0034] For example, as shown in Figure 7, when the distance between the terminal UE and the repeater 10 is 1 m, the direction difference to the base station BS on the perpendicular bisector is 5.22° or less if the distance between the repeater 10 and the base station BS is 11 m or more. This direction difference of "5.22° or less" is less than one control step (5.6°, for example) of the antenna beam direction in an existing high-precision beam control IC, so it is essentially the same direction in terms of controlling the antenna beam direction.

[0035] As shown in Figures 6, 8, and 9, reference direction axes (X, Y, Z) are determined in advance for the terminal UE and the repeater 10. Also, as shown in Figures 8 and 9, a reference direction Dir(B1) is determined in advance for the terminal UE and the repeater 10. For example, the reference direction axes (X, Y, Z) are defined as axes in which the front of the housing of each of the terminal UE and the repeater 10 is in the positive X-axis direction, the left is in the positive Y-axis direction, and the top is in the positive Z-axis direction (Figures 8(1), (2), and 9(1), (2)). Also, the direction in which the orientations of the housings of each of the terminal UE and the repeater 10 coincide with the reference direction axes (X, Y, Z) is defined as the reference direction Dir(B1) (Figures 8(1), (2), and 9(1), (2)).

[0036] The terminal UE and the repeater 10 are equipped with a rotation angle detection sensor (not shown) that detects the rotation angle of the housing relative to the reference direction axes (X, Y, Z). For example, an acceleration sensor or a geomagnetic sensor may be used as the rotation angle detection sensor. Hereinafter, the rotation angle of the housing of the terminal UE will be referred to as the rotation angle of the terminal UE. Furthermore, the rotation angle of the housing of the repeater 10 will be referred to as the rotation angle of the repeater 10.

[0037] As shown in Fig. 6, the terminal UE notifies the repeater 10 of its own rotation angle (D1) and beam selection information for the base station (B1). The beam selection information for the base station (B1) is information (for example, a beam identifier for the base station (beam ID for the base station)) indicating an antenna beam Bm_UE2 to be directed toward the base station BS of the terminal UE, which has been determined for the direction DIR_UE from the terminal UE to the base station BS. The repeater 10 selects an antenna beam Bm_RS2 (B2) to be directed toward its own base station BS using its own rotation angle (D2), the rotation angle (D1) of the terminal UE, and the beam selection information for the base station (B1).

[0038] The beam selection phase between the base station BS and the repeater 10 will be described with reference to Figure 5. The terminal UE can transmit and receive signals to and from the base station BS using an antenna beam Bm_UE2 directed toward the base station BS. The base station BS can also transmit and receive signals to and from the terminal UE using an antenna beam Bm_BS1.

[0039] (Step S1) The base station BS determines a measurement schedule between the base station BS and the terminal UE. This measurement schedule is a schedule for sequentially measuring "k2 x l" combinations of antenna beams Bm_UE2 and Bm_BS1 of the terminal UE and the base station BS.

[0040] (Step S2) The base station BS notifies the terminal UE of schedule information indicating the determined measurement schedule.

[0041] (Step S3) The base station BS transmits the measurement signal using the antenna beam Bm_BS1 in accordance with the determined measurement schedule.

[0042] (Step S4) The terminal UE sequentially measures the "k2 x l" combinations of the terminal UE and the antenna beams Bm_UE2, Bm_BS1 of the base station BS in accordance with the measurement schedule notified by the base station BS. In this measurement, wireless quality such as received signal strength and signal-to-noise ratio (SN ratio) is measured for each of the "k2 x l" combinations of the terminal UE and the antenna beams Bm_UE2, Bm_BS1 of the base station BS.

[0043] (Step S5) The terminal UE notifies the base station BS of the measurement result.

[0044] (Step S6) The base station BS determines a combination of antenna beams Bm_UE2 and Bm_BS1 of the terminal UE and the base station BS based on the measurement results notified from the terminal UE.

[0045] (Step S7) The base station BS notifies the terminal UE of beam determination information indicating the determined antenna beam Bm_UE2 for the terminal UE.

[0046] (Step S8) The terminal UE and the repeater 10 execute a repeater beam determination method for the base station to determine the antenna beam Bm_RS2 that the repeater 10 will direct to the base station BS, based on the antenna beam Bm_UE2 of the terminal UE indicated in the beam determination information notified from the base station BS. Figure 10 shows the procedure of the repeater beam determination method for the base station.

[0047] Fig. 10 is a flowchart showing an example of the procedure of the repeater's method for determining a beam for a base station according to this embodiment. The repeater's method for determining a beam for a base station according to this embodiment (step S8 in Fig. 5) will be described with reference to Fig. 10. The repeater's method for determining a beam for a base station in Fig. 10 is executed for each repeater 10.

[0048] (Step S101) The terminal UE and the relay 10 establish a wireless link by the respective wireless communication units 210 and 110. The control unit 250 of the terminal UE and the control unit 140 of the relay 10 communicate with each other via the established wireless link.

[0049] The setting of the pair of the terminal UE and the repeater 10 that establishes the wireless link may be performed in advance, for example, at the time of shipping the terminal UE and the repeater 10. In this case, the pair of the terminal UE and the repeater 10 is sold to the user U. Alternatively, the user U may set up a pair of the terminal UE and the repeater 10 that establishes a radio link. In this case, the user U can set up a pair of the terminal UE and the repeater 10 for any terminal UE and the repeater 10. Alternatively, the setting of the pair of the terminal UE and the relay 10 that establishes the wireless link may be performed automatically, for example, when the wireless communication units 210 and 110 are capable of short-distance wireless communication.

[0050] (Step S102) The control unit 250 of the terminal UE notifies the relay 10 of the beam direction information for the base station of the terminal UE itself. At this time, the same beam direction information for the base station is notified to each relay 10. The beam direction information for the base station of the terminal UE is information indicating the correspondence between the identifiers (beam IDs for the base station) of k2 antenna beams that can be formed as the antenna beam (beam for the base station) Bm_UE2 of the terminal UE directed towards the base station BS, and the direction of the beam for the base station of the terminal UE. The direction of the beam for the base station of the terminal UE is expressed as a direction relative to the reference direction Dir(B1). The beam direction information for the base station of the terminal UE is stored in advance in the storage unit 240 of the terminal UE. The control unit 140 of the repeater 10 stores in the storage unit 130 the beam direction information for the base station of the terminal UE notified from the terminal UE.

[0051] An example of the correspondence relationship between the beam ID (n, n is a positive integer from 1 to N) for the base station of the terminal UE and the direction of direction is shown in Fig. 11. In the example of Fig. 11, the direction of the beam ID (n) for the base station of the terminal UE is represented by a unit vector (x_n, y_n, z_n) of the direction of direction relative to the reference direction Dir(B1).

[0052] The correspondence between the beam ID(n) for the base station of the terminal UE and the pointing direction may be set in advance in the repeater 10, for example, at the time of product shipment or sale. In this case, step S102 may be omitted.

[0053] (Step S103) The control unit 250 of the terminal UE detects the rotation angle (terminal rotation angle) (D1=(φ D1 , θ D1 , ψ D1 )) is measured (see Figure 8(3)).

[0054] (Step S104) The control unit 250 of the terminal UE notifies the repeater 10 of the measured terminal rotation angle (D1) and the identifier of the beam Bm_UE2 for the base station of the terminal UE (beam ID (B1) for the base station of the terminal UE) indicated in the beam determination information notified by the base station BS in step S7. The control unit 140 of the relay 10 stores in the storage unit 130 the terminal rotation angle (D1) notified from the terminal UE and the beam ID (B1) for the base station of the terminal UE in association with each other.

[0055] (Step S105) The control unit 140 of the repeater 10 detects the rotation angle (repeater rotation angle) (D2=(φ D2 , θ D2 , ψ D2 ) is measured (see Figure 9(3)).

[0056] (Step S106) The control unit 140 of the relay 10 calculates the difference (ΔD) in the orientation between the terminal UE and the relay 10 using the following equation. ΔD = Repeater rotation angle (D2) - Terminal rotation angle (D1) = (φ D2 - φ D1, θ D2 -θ D1 , ψ D2 - ψ D1 )

[0057] (Step S107) The control unit 140 of the repeater 10 acquires the direction BDir(B1) of the beam for the base station of the terminal UE corresponding to the beam ID (B1) for the base station of the terminal UE from the direction direction information of the beam for the base station of the terminal UE stored in the memory unit 130. The control unit 140 calculates an estimate of the direction of the base station BS as seen from the housing of the repeater 10 (repeater's base station direction estimate) Dir_D2toBS using the following formula from the direction BDir(B1) of the beam for the base station of the terminal UE corresponding to the beam ID (B1) for the base station of the terminal UE and the difference (ΔD) in the direction between the terminal UE and the repeater 10. Dir_D2toBS=Rz(-(ψ D2 - ψ D1 ))Ry(-(θ D2 -θ D1 ))Rx(-(φD2 - φ D1 ))BDir(B1)=(X Dir_D2toBS , Y Dir_D2toBS , Z Dir_D2toBS )

[0058] Rz(ψ) is a rotation matrix that rotates ψ around the Z axis. Ry(θ) is a rotation matrix that rotates θ around the Y axis. Rx(φ) is a rotation matrix that rotates φ around the X axis.

[0059] (Step S108) The control unit 140 of the repeater 10 determines the antenna beam (B2) whose direction is closest to the repeater's base station direction estimate value Dir_D2toBS as the antenna beam Bm_RS2 that the repeater 10 will direct to the base station BS from among the k1 antenna beams that the repeater 10 can form as the antenna beam Bm_RS2 that the repeater 10 will direct to the base station BS.

[0060] 12 shows an example of the correspondence between the identifier (base station beam ID (m, where m is a positive integer from 1 to M)) of the antenna beam (base station beam) directed toward the base station BS of the repeater 10 and the direction of direction. In the example of FIG. 12, the direction of the base station beam ID (m) of the repeater 10 is represented by a unit vector (x_m, y_m, z_m) of the direction of direction relative to the reference direction Dir(B1).

[0061] The antenna beam (B2) whose direction of direction is closest to the repeater's base station direction estimate value Dir_D2toBS may be the antenna beam with the smallest value P_B2 in the following equation among the antenna beams with the repeater 10's beam ID (m, where m is a positive integer from 1 to M) for the base station. P_B2=√{(X Dir_D2toBS - x_m) 2 + (Y Dir_D2toBS - y_m) 2 + (Z Dir_D2toBS - z_m) 2}

[0062] The procedure of the repeater's beam determination method for the base station shown in Figure 10 is repeated repeatedly, thereby adapting to changes in the terminal rotation angle (D1) and the repeater rotation angle (D2) due to the movement of the user U.

[0063] The above is the description of the beam selection phase between the base station BS and the repeater 10. 10, the terminal UE notifies the repeater 10 of the beam ID for the base station as the beam selection information for the base station (B1), but this is not limited to this. The terminal UE may notify the repeater 10 of information representing the direction of the beam for the base station of the terminal UE in terms of an azimuth as the beam selection information for the base station (B1). In this case, step S102 in FIG. 10 may be omitted.

[0064] [Beam selection phase between each repeater 10 and terminal UE] The beam selection phase between each repeater 10 and the terminal UE will now be described. In the beam selection phase between each repeater 10 and the terminal UE, a combination of an antenna beam Bm_RS1 that the repeater 10 will point toward the terminal UE and an antenna beam Bm_UE1 that the terminal UE will point toward the repeater 10 is determined for each repeater 10.

[0065] The number of antenna beams that the repeater 10 can form as the antenna beam Bm_RS1 directed toward the terminal UE is j. The number of antenna beams that the terminal UE can form as the antenna beam Bm_UE1 directed toward the repeater 10 is i. Therefore, for one repeater 10, one antenna beam combination is selected from the "i x j" combinations of antenna beams. This method is not limited. For example, for one repeater 10, the best antenna beam combination may be selected from the "i x j" combinations of antenna beams based on the results of measuring all the combinations of antenna beams.

[0066] The beam selection phase between each repeater 10 and the terminal UE will be described with reference to Fig. 5. Here, for convenience of explanation, the explanation will be given for the terminal UE and one repeater 10, but the same applies to each repeater 10.

[0067] The terminal UE and the repeater 10 communicate with each other via a wireless link established by each of the wireless communication units 210 and 110 .

[0068] (Step S11) The terminal UE transmits a measurement signal using antenna beam Bm_UE1 in accordance with a predetermined measurement schedule. This measurement schedule is shared in advance between the terminal UE and the repeater 10. The measurement schedule is a schedule for sequentially measuring "i x j" combinations of antenna beams Bm_UE1 and Bm_RS1 of the terminal UE and the repeater 10.

[0069] (Step S12) In accordance with a predetermined measurement schedule, the repeater 10 sequentially measures "i x j" combinations of the terminal UE and the antenna beams Bm_UE1, Bm_RS1 of the repeater 10. In this measurement, for each "i x j" combination of the terminal UE and the antenna beams Bm_UE1, Bm_RS1 of the repeater 10, wireless quality such as received signal strength and signal-to-noise ratio (SN ratio) is measured.

[0070] (Step S13) The repeater 10 notifies the terminal UE of the measurement result.

[0071] (Step S14) The terminal UE determines a combination of the antenna beams Bm_UE1 and Bm_RS1 of the terminal UE and the relay 10 based on the measurement result notified by the relay 10.

[0072] (Step S15) The terminal UE notifies the relay 10 of beam determination information indicating the determined antenna beam Bm_RS1 of the relay 10.

[0073] The above is the description of the beam selection phase between each repeater 10 and the terminal UE.

[0074] By the wireless relay method of Figure 5 described above, antenna beam Bm_UE1, antenna beam Bm_RS1, antenna beam Bm_RS2 and antenna beam Bm_BS1 are dynamically determined so that the direction of the antenna beams faces each other between the base station BS and the repeater 10 and between the repeater 10 and the terminal UE, respectively.

[0075] According to this embodiment, the beam for the base station of the repeater 10 is determined based on the beam for the base station of the terminal UE, and therefore, an effect is obtained in that the beam for the base station of the repeater 10 can be easily determined.

[0076] According to this embodiment, it is possible to reduce the number of combinations of antenna beams to be measured for selecting the antenna beam Bm_UE1, the antenna beam Bm_RS1, the antenna beam Bm_RS2, and the antenna beam Bm_BS1.

[0077] Conventionally, for one terminal and one repeater, it was necessary to measure "i×j×k1×l" combinations of antenna beam Bm_UE1 (i combinations), antenna beam Bm_RS1 (j combinations), antenna beam Bm_RS2 (k1 combinations), and antenna beam Bm_BS1 (l combinations). In contrast, in this embodiment, for one terminal and one repeater, it is sufficient to measure "k2×l" combinations of antenna beam Bm_UE2 (k2 combinations) and antenna beam Bm_BS1 (l combinations) (beam selection phase between base station BS and repeater 10) and "i×j" combinations of antenna beam Bm_UE1 (i combinations) and antenna beam Bm_RS1 (j combinations) (beam selection phase between each repeater 10 and terminal UE), for a total of "k2×l+i×j" combinations. In particular, when the number k2 of antenna beams that can be formed as the antenna beam Bm_UE2 directed toward the base station BS of the terminal UE and the number k1 of antenna beams that can be formed as the antenna beam Bm_RS2 directed toward the base station BS of the repeater 10 are approximately the same, the number of measurements in this embodiment, "k2×l+i×j", is significantly reduced compared to the conventional number of measurements, "i×j×k1×l".

[0078] Therefore, according to this embodiment, it is possible to shorten the measurement time for selecting the antenna beam Bm_UE1, the antenna beam Bm_RS1, the antenna beam Bm_RS2, and the antenna beam Bm_BS1, which reduces the possibility that the terminal UE and the user U having the repeater 10 move during the measurement, thereby contributing to the selection of the best combination of antenna beams.

[0079] Furthermore, even when multiple repeaters 10 are used for one terminal UE, the beam for the base station of each repeater 10 is determined based on the common base station beam of the terminal UE, thereby achieving the effect of easily determining the beam for the base station of the repeater 10.

[0080] This will enable, for example, improvements to the overall service quality of wireless systems, thereby contributing to Goal 9 of the United Nations-led Sustainable Development Goals (SDGs), which is to "Build resilient infrastructure, promote sustainable industrialization and foster innovation."

[0081] 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.

[0082] The above-described embodiment is applicable to various wireless systems, such as a mobile communication system or a broadcasting system.

[0083] 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.

[0084] 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]

[0085] 1...wireless system, UE...wireless terminal, BS...base station, 10...wireless relay device, 110, 210...wireless communication unit, 120...relay communication unit, 130, 240...storage unit, 130, 250...control unit, 121...terminal side communication unit, 122...base station side communication unit, 220...base station side communication unit, 230...relay side communication unit, DVa, DVb, DVc, DVd, DVe...device

Claims

1. a wireless relay device that relays signals transmitted and received between a base station and a wireless terminal; the wireless terminal transmitting and receiving signals to and from the base station via the wireless relay device, the wireless terminal includes a terminal control unit that notifies the wireless relay device of terminal beam information indicating a direction of an antenna beam of the wireless terminal that is directed toward the base station, the direction having been determined between the wireless terminal and the base station; the wireless relay device includes a relay device control unit that determines an antenna beam of the wireless relay device to be directed toward the base station based on the direction indicated by the terminal beam information notified from the wireless terminal. Radio system.

2. The terminal beam information is a rotation angle of the wireless terminal relative to a reference orientation of the wireless terminal and the wireless relay device; and information representing a direction of an antenna beam of the wireless terminal directed toward the base station, which has been determined between the wireless terminal and the base station, in terms of a direction relative to the reference direction.

2. The wireless system of claim 1.

3. The terminal beam information includes information representing, by an azimuth, a direction of an antenna beam of the wireless terminal directed toward the base station, which has been determined between the wireless terminal and the base station.

2. The wireless system of claim 1.

4. a plurality of the wireless relay devices are provided for one of the wireless terminals; the plurality of radio relay devices determine the antenna beam of the radio relay device, respectively, using the common terminal beam information notified from one of the radio terminals; 4. A wireless system according to claim 1.

5. A wireless relay device that relays signals transmitted and received between a base station and a wireless terminal, a relay device control unit that receives, from the wireless terminal, notification of terminal beam information indicating a direction of an antenna beam of the wireless terminal to be directed toward the base station, which direction has been determined between the wireless terminal and the base station, and determines the antenna beam of the wireless relay device to be directed toward the base station based on the direction of direction indicated by the terminal beam information notified from the wireless terminal; A wireless relay device comprising:

6. In a wireless terminal that transmits and receives signals to and from a base station via a wireless relay device, a terminal control unit that notifies the wireless relay device of terminal beam information indicating a direction of an antenna beam of the wireless terminal that is directed toward the base station, the direction having been determined between the wireless terminal and the base station; A wireless terminal comprising:

7. a wireless relay device that relays signals transmitted and received between a base station and a wireless terminal; the wireless terminal transmitting and receiving signals to and from the base station via the wireless relay device, the wireless terminal notifies the wireless relay device of terminal beam information indicating a direction of an antenna beam of the wireless terminal directed toward the base station, the direction of the antenna beam having been determined between the wireless terminal and the base station; the wireless relay device determines an antenna beam of the wireless relay device to be directed toward the base station based on the direction indicated by the terminal beam information notified from the wireless terminal; Radio relay method.

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