Beam Antenna Device

Abstract

To provide a beam antenna device which performs beam tracking for an aircraft circling in the air even if it cannot rotate forever in the pan direction. [Solution] In a communication system, a beam antenna device 1 comprises a flat plate portion 10, a first rotating body 12 that rotates around a first axis 21 perpendicular to the flat plate portion but does not permanently rotate relative to the flat plate portion, a second rotating body 14 that rotates around a second axis 23 perpendicular to the first axis, a planar antenna 16 that is provided on the second rotating body in a direction perpendicular to the second axis and directs antenna directivity 30 in a fixed direction as viewed from the second rotating body, and a control unit that controls the rotation of the first rotating body and the second rotating body, and the flat plate portion is installed at a predetermined angle Θ with respect to the horizontal line 41.

Description

[Technical field]

[0001] The present invention relates to a beam antenna device which forms antenna directivity for communication. [Background technology]

[0002] Conventionally, there is a technology for forming antenna directivity (beamforming) to suppress interference between communication with other parties in communication with a communication partner. In addition, a technology has been developed for communicating with smartphones and the like by installing a base station in the air where there is little possibility of reflected waves or diffraction. Patent Document 1 discloses a technology for equipping an aircraft with a base station function and performing beamforming control on the terminal. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2024-126594 A Summary of the Invention [Means for solving the problem]

[0004] In one embodiment of the present invention, a beam antenna device comprises a flat plate portion, a first rotating body that rotates about a first axis perpendicular to the flat plate portion, the first rotating body not permanently rotating relative to the flat plate portion, a second rotating body that rotates about a second axis perpendicular to the first axis, an antenna that is provided on the second rotating body in a direction perpendicular to the second axis and directs antenna directivity in a fixed direction as viewed from the second rotating body, and a control unit that controls the rotation of the first rotating body and the second rotating body, and the flat plate portion is installed at a predetermined angle with respect to the horizontal plane.

[0005] In the above beam antenna device, the beam antenna device may be configured to orient antenna directivity toward an aircraft circling in the sky.

[0006] In the above beam antenna device, the aircraft may be a High Altitude Platform Station (HAPS).

[0007] Furthermore, in the above beam antenna device, the beam antenna device may be installed within a range vertically below a turning circle about which the HAPS turns.

[0008] In the above beam antenna device, the installation angle of the beam antenna device is defined as (θ, ψ azimuth )year, θ is the angle of the plate part with respect to the horizontal plane, ψ azimuth is the azimuth angle, which is the rotation angle from true north to which the reference direction of the flat plate on the horizontal plane faces when true north is set to 0 degrees, The tilt limit angle is θ tilt_max , the limit angular velocity in the pan direction is ω pan_max year, When the relative position from the position of the HAPS beam antenna device at time t is (x(t), y(t), z(t)),

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[0016] The angle θ that satisfies the formulas (2) and (3) may be set as the predetermined angle.

[0017] In addition, in the above beam antenna device, the beam antenna device is An acquisition unit that acquires the current relative position (x, y, z) of the HAPS; The current relative position satisfies the following:

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[0021] The rotation of the first rotating body and the second rotating body may be controlled so as to satisfy the above condition. [Brief description of the drawings]

[0022] [Figure 1] FIG. 2 is a perspective view showing the appearance of a beam antenna device. [Diagram 2] FIG. 1 is an overview showing a configuration example of a conventional communication system. [Diagram 3] FIG. 1 is an overview showing a configuration example of a communication system. [Figure 4] FIG. 2 is a perspective view showing the appearance of a beam antenna device. [Diagram 5] 1 is a block diagram showing an example of the configuration of a beam antenna device. [Figure 6] 5 is a flowchart showing an example of the operation of the beam antenna device. [Figure 7] 1A to 1C are first diagrams showing an example of a deformation process of a beam antenna device. [Figure 8] 11 is a second diagram showing an example of a deformation process of the beam antenna device. FIG. [Figure 9] 11 is a graph showing an example of change in the angle of rotation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0023] In recent years, as wireless communication base stations are placed at high altitudes, their communication areas can be expanded, leading to the development of communication systems using HAPS (High Altitude Platform System), a high-altitude platform that mounts wireless stations on aircraft flying at high altitudes.

[0024] This HAPS also communicates with ground stations, and works in conjunction with communication systems deployed on the ground to provide communication services to users' wireless terminals. For this reason, ground stations must be in constant communication with the HAPS. To ensure good communication with the HAPS, ground stations form their antenna directivity toward the HAPS in the air and communicate with it. Forming antenna directivity allows for good communication within the range of the formed antenna directivity, but forming the antenna directivity narrows the communication range. For this reason, in order to communicate with the HAPS circling in the air, ground stations must constantly form their antenna directivity toward the HAPS and continue to follow it.

[0025] Therefore, a beam antenna device 1 that forms antenna directivity for the HAPS in order to continue tracking (hereinafter, antenna directivity is referred to as a beam, and forming antenna directivity is sometimes referred to as beam tracking) is considered.

[0026] As shown in FIG. 1, the beam antenna device 1 may be composed of a flat plate portion 10, a first shaft portion 11, a first rotating body 12, a second shaft portion 13, a second rotating body 14, an antenna installation portion 15, and a planar antenna 16. The flat plate portion 10 is a flat plate, and the first shaft portion 11 is an axis perpendicular to the plane formed by the flat plate portion 10. The first rotating body 12 rotates around the first shaft portion 11, i.e., around a first axis 21. The second shaft portion 13 is provided on the first rotating body 12 and is an axis perpendicular to the first shaft portion 11. The second rotating body 14 rotates around the second shaft portion 13, i.e., around a second axis 23. The antenna installation portion 15 is a base portion for mounting an antenna fixed to the second rotating body 14, and the planar antenna 16 is provided thereon. The planar antenna 16 may be a planar antenna for general satellite communications, and forms an antenna directivity in a direction perpendicular to the plane of the planar antenna.

[0027] When the beam antenna device 1 forms antenna directivity with the HAPS and communicates with it as shown in FIG. 2, the first rotating body 12 is rotated around the first shaft portion 11 while the second rotating body 14 is rotated around the second shaft portion 13, so that the beam 30 formed by the planar antenna 16 mounted on the antenna installation portion 15 can be directed toward the HAPS 100. Meanwhile, the HAPS 100 continues to rotate in the same direction while tracing a rotation orbit 101. Therefore, the first rotating body 12 needs to be configured to continue to rotate infinitely around the first shaft portion 11. Infinite rotation means that the beam antenna device 1 continues to rotate in the same direction. In other words, in the state shown in FIG. 2, the beam antenna device 1 continues to rotate in one direction in the pan direction (also called the yaw direction). If the beam antenna device 1 cannot rotate infinitely, it is necessary to return the rotation of the first rotating body 12 to the original, that is, from the end of the rotation to the opposite side, in order to direct the beam toward the HAPS 100, and during that time, there is a time when beam tracking to the HAPS cannot be performed. At this time, there is a problem that wireless communication between the wireless terminals 300a and 300b for which the HAPS is providing communication services may be interrupted.

[0028] Therefore, in this embodiment, the object is to provide a beam antenna device 1 as shown in Figure 1, in which the first rotating body 12 cannot rotate infinitely about the first axis portion 11, i.e., the beam antenna device 1 cannot rotate infinitely in the pan direction, but which can provide wireless communication services by performing beam tracking to follow the HAPS 100.

[0029] Fig. 3 is a diagram showing a schematic diagram of a communication system according to this embodiment. As shown in Fig. 3, the communication system includes a HAPS 100, which glides and rotates in the air to describe a circular orbit 101. As a communication base station, the HAPS 100 communicates with wireless terminals used by users on the ground and provides wireless communication services to the wireless terminals of the users. The HAPS 100 also communicates with a ground station equipped with a beam antenna device 1.

[0030] By installing this beam antenna device 1 at an angle as shown in Figure 3, rather than in the state shown in Figure 1, in other words so that the flat plate portion 10 is at a predetermined angle θ with respect to the horizontal plane, even if the first rotating body 12 cannot rotate infinitely around the first shaft portion 11, it is possible for the first rotating body 12 to continue to follow the HAPS 100 and perform beam tracking. The details will be explained below.

[0031] <Configuration> Fig. 4 is a perspective view showing the outer shape of the beam antenna device 1. The beam antenna device 1 according to this embodiment is installed and operated at an angle as shown in Fig. 3, unlike the beam antenna device 1 shown in Fig. 1.

[0032] As shown in Figure 4, the beam antenna device 1 may be composed of a flat plate portion 10, a first axis portion 11, a first rotating body 12, a second axis portion 13, a second rotating body 14, an antenna installation portion 15, and a planar antenna 16.

[0033] The flat plate portion 10 is a flat plate. The flat plate portion 10 is actually installed at a predetermined angle θ with respect to a horizontal plane.

[0034] A first shaft portion 11 is connected to the flat plate portion 10.

[0035] Further, a first rotor 12 is connected to the first shaft portion 11.

[0036] The first rotating body 12 rotates around the first axis 21 of the first shaft portion 11, but cannot rotate infinitely. The first rotating body 12 may be configured to be rotatable relative to the first shaft portion 11, or may be configured to be fixed to the first shaft portion 11 so that the first shaft portion 11 can rotate relative to the flat plate portion 10. The first rotating body 12 may be rotated by a motor (not shown). The first rotating body 12 (first axis 21) is an axis perpendicular to the plane formed by the flat plate portion 10.

[0037] The first rotating body 12 is provided with a second shaft portion 13. The second rotating body 14 is connected to the second shaft portion 13. The second rotating body 14 rotates about a second axis 23 of the second shaft portion 13. The second rotating body 14 may be configured to be rotatable relative to the second shaft portion 13, or may be fixed to the second shaft portion 13 so that the second shaft portion 13 is rotatable relative to the first rotating body 12. The second shaft portion 13 (second axis 23) is an axis perpendicular to the first axis 21.

[0038] An antenna installation section 15 is connected to the second rotating body 14. The antenna installation section 15 is a base section on which a planar antenna 16 is placed, and the planar antenna 16 forms antenna directivity and communicates with the HAPS 100. In this embodiment, the planar antenna 16 is used, but the planar antenna 16 may be a parabolic antenna.

[0039] The beam antenna device 1 is installed on the ground within a range vertically below the circular orbit 101 described by the HAPS 100, i.e., within the range of a circle 102, as shown in Fig. 3. The beam antenna device 1 is connected to a ground station (terrestrial gateway station) or is provided at the ground station, and communicates with the HAPS 100. Note that the shape of the beam antenna device 1 is not limited to that shown in the figure, as long as it has the above-mentioned configuration.

[0040] <Example of functional configuration> FIG. 5 is a functional block diagram showing an example of the configuration of an information processing device that controls the beam antenna device 1. As shown in FIG.

[0041] As shown in FIG. 5, the beam antenna device 1 includes a communication unit 110, an input unit 120, a control unit 130, a storage unit 140, and a drive unit 150.

[0042] The communication unit 110 has a function of communicating with a connected ground station. The communication unit 110 also has a function of communicating with the HAPS 100 via the planar antenna 16. The communication unit 110 forms antenna directivity (beam 30) for the HAPS 100 and communicates with the HAPS 100. The communication unit 110 also receives information indicating the position of the HAPS 100 from the ground station and transmits the information to the control unit 130.

[0043] The input unit 120 is an input interface provided in the beam antenna device 1 for inputting information to the beam antenna device 1. The input unit 120 may be realized by, for example, a keyboard, a touch panel, etc. The input unit 120 may receive, for example, an input of information indicating the position of the HAPS 100, and transmit the information to the control unit 130.

[0044] The control unit 130 is a processor that controls each unit of the beam antenna device 1. The control unit 130 executes various programs by referring to various data stored in the storage unit 140, and realizes the functions that the beam antenna device 1 should fulfill.

[0045] The control unit 130 includes an acquisition unit 131, a calculation unit 132, and a drive control unit 133 as functions to be performed by the beam antenna device 1.

[0046] The acquisition unit 131 acquires (receives) information indicating the position of the HAPS 100 via the communication unit 110 or the input unit 120 and transmits the information to the calculation unit 132.

[0047] The calculation unit 132 calculates the rotation angles of the first rotor 12 and the second rotor 14 based on the position of the HAPS 100 transmitted from the communication unit 110 or the input unit 120.

[0048] Here, a method for calculating the angle θ at which the beam antenna device 1 is inclined and the rotation angle of each rotator will be described.

[0049] First, the installation angle of the beam antenna device 1 is defined as (θ, ψ azimuth ) As shown in FIG. 4, θ is the angle between the horizontal plane 41 (horizontal line in the drawing) of the flat plate portion 10. Also, as shown in FIG. 4, ψ azimuth is the angle between the reference direction 42 of the flat plate portion 10 on a virtual horizontal plane and true north as an azimuth angle. The reference direction 42 is ψ azimuth When ψ is 0, it corresponds to true north. The reference direction 42 may be any direction that determines the orientation of the flat-plate unit 10 as determined by the user when the flat-plate unit 10 is placed on a horizontal plane. azimuth Strictly speaking, is the angle between the direction of the reference direction when it is lowered onto a virtual horizontal plane and true north. In Fig. 4, the dotted arrow indicating true north and the dotted arrow indicating reference direction 42 are arrows on a virtual horizontal plane, and the virtual horizontal plane may be a plane parallel to the horizontal plane.

[0050] When the position of the beam antenna device 1 is taken as the origin, and the true north direction is taken as the x-axis, the relative position of the HAPS100 at time t is taken as (x(t), y(t), z(t)), and the reference direction of the flat plate part is taken as the x-axis, the relative position of the HAPS100 at time t is taken as (X(θ,t),Y(θ,t),Z(θ,t)),

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[0052] In the above formula (1), Ry and Rz are rotation matrices and satisfy the following:

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[0057] Here, the limit angle of tilt (the limit angle that the second rotating body 14 can take relative to the first rotating body 12 and the limit angle at which it can rotate around the second axis 23) is defined as θ tilt_max , the limit angular velocity in the pan direction (the limit angular velocity around the first axis 21 of the first rotor 12 of the beam antenna device 1) is ω pan_max Let us assume that.

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[0060] In this case, θ that satisfies the above formulas (2) and (3) is defined as the angle that the flat plate portion 10 makes with respect to the horizontal plane (the angle at which the beam antenna device 1 should be installed at an angle). In this manner, the angle θ that the flat plate portion 10 makes with respect to the horizontal plane can be specified.

[0061] Then, the calculation unit 132 calculates, from the current relative position (x, y, z) of the HAPS 100 transmitted from the communication unit 110 or the input unit 120 and the following formula (4),

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[0065] That is, the rotation angle of the first rotating body 12 is calculated as equation (5), and the rotation angle of the second rotating body 14 is calculated as equation (6). The calculation unit 132 transmits the calculated rotation angles of the first rotating body 12 and the second rotating body 14 to the drive control unit 133. In this manner, the control angles of both rotating bodies can be calculated.

[0066] The drive control unit 133 controls the drive unit 150 to control both motors so that the rotation angles of the first rotating body 12 and the second rotating body 14 match the calculated rotation angles based on the rotation angles of the first rotating body 12 and the second rotating body 14 calculated by the calculation unit 132.

[0067] The storage unit 140 has a function of storing various programs and data required for the operation of the beam antenna device 1. The storage unit 140 can be realized by, for example, a hard disk drive (HDD), a solid state drive (SSD), a flash memory, etc., but is not limited to these. The storage unit 140 may be a cloud storage accessible by the beam antenna device 1. The storage unit 140 may store various programs and various data for realizing the functions to be performed by the beam antenna device 1. The storage unit 140 may store a program for calculating the rotation angle of a motor that controls the rotation of the first rotating body 12 and the rotation angle of a motor that controls the rotation of the second rotating body 14 based on the relative positional relationship between the beam antenna device 1 and the HAPS 100, a program for controlling the rotation of the first rotating body 12 and the second rotating body 14 based on the calculated rotation angle, and the like.

[0068] The driving unit 150 drives a motor that controls the rotation of the first rotor 12 and a motor that controls the rotation of the second rotor 14 of the beam antenna device 1. The driving unit 150 controls both motors in accordance with instructions from the control unit 130, and controls the direction in which the beam 30 is directed.

[0069] The above is an example of the configuration of the beam antenna device 1.

[0070] <Operation> FIG. 6 is a flowchart showing the operation of the beam antenna device 1 for tracking the HAPS 100 and directing the beam 30.

[0071] As shown in FIG. 6, the communication unit 110 or the input unit 120 of the beam antenna device 1 acquires information indicating the position of the HAPS 100 (relative position information) from the connected ground station, and transmits it to the control unit 130 (step S601).

[0072] The calculation unit 132 of the control unit 130 calculates the rotation angle of the first rotating body 12 and the rotation angle of the second rotating body 14 based on the relative position of the HAPS 100 using the above formulas (5) and (6) (step S602). The calculation unit 132 transmits the calculated rotation angles to the drive control unit 133 together with information indicating which of the respective rotation angles these are.

[0073] The drive control unit 133 instructs the drive unit 150 to control the respective motors so that the corresponding rotating bodies (first rotating body 12, second rotating body 14) have the transmitted rotation angle. The drive unit 150 controls the motors of the respective rotating bodies so that the rotating bodies have the rotation angles transmitted from the drive control unit 133 (step S603), and ends the process.

[0074] 6 every time it acquires the position information of the HAPS 100. This allows the beam antenna device 1 to always irradiate the beam 30 in the direction in which the HAPS 100 is located, i.e., to orient the antenna directivity.

[0075] <Rotation example> 7 and 8 show examples of the rotation of the beam antenna device 1, as viewed from the same direction, when tracking the HAPS 100 in the air. The arrow from the planar antenna 16 in the figures indicates the direction of the beam, and the direction of the HAPS 100. Although the examples shown in Figures 7 to 8 are for half a rotation, as can be seen from the changes in the beam antenna device 1 from Figure 7 to Figure 8, it is possible to track the HAPS 100 in a circular orbit.

[0076] Fig. 9 is a graph showing the change in the control angle (rotation angle) of the pan angle and tilt angle. Fig. 9 shows an example of change (control example) in the rotation angle when the aircraft is rotating at a speed of 250 km / h, has a radius of 2.5 km, and is 3 km directly above the beam antenna device 1, and the beam antenna device 1 is located at the center of the turning circle. In Fig. 9, the solid line 91 indicates the change in the pan angle (ψ) when the tilt angle θ of the flat plate portion 10 is set to 45 degrees. pan ) change, and the dotted line 92 indicates the change in the tilt angle (φ tiltThe dashed line 93 shows the change in the pan angle (ψ) when the inclination angle θ of the flat plate portion 10 is set to 55 degrees. pan ), and the dotted line 92 shows the change in the tilt angle (φ tilt 9 shows an example of the change in angle when the HAPS100 follows one revolution of a circular orbit, and as can be seen from the pan angle (solid line 91, dashed line 93), it can be seen that the HAPS100 can follow without rotating 360 degrees. In other words, the HAPS100 can follow without rotating infinitely in the pan direction.

[0077] <Summary> As described above, the beam antenna device 1 comprises a flat plate portion 10, a first axis portion 11 arranged perpendicular to the flat plate portion 10, a first rotating body 12 that rotates about the first axis portion 11, and a second rotating body 14 that rotates about a second axis portion 13 provided on the first rotating body 12 and has an antenna installation portion 15 provided thereon.By installing the beam antenna device 1 so that the flat plate portion 10 is inclined to the horizontal plane, it is possible to maintain communication by performing uninterrupted beam tracking on the HAPS 100 orbiting in the air, even if the first rotating body 12 does not rotate permanently around the first axis portion 11.

[0078] <Modification> The beam antenna device 1 and the terminal device 300 according to the above embodiment are not limited to the above embodiment, and may be realized by other methods. Various modified examples will be described below.

[0079] (1) In the above embodiment, an example has been described in which the beam antenna device 1 performs beam tracking on a HAPS rotating in the air to perform communication, but the target for which the beam antenna device 1 performs beam tracking is not limited to a HAPS. Any flying object that rotates in the air and has a communication function may be used, such as an airplane, a drone, a helicopter, or an airship.

[0080] (2) In the above embodiment, the beam antenna device 1 is installed at an angle, but this may be configured such that the beam antenna device 1 is installed at an angle by providing a third rotation shaft parallel to the flat plate portion 10 and a motor on the flat plate portion 10 of the beam antenna device 1 shown in Fig. 1, and driving the motor to rotate the flat plate portion 10 to a predetermined angle θ, thereby making the beam antenna device 1 at an angle. In this case, prior to the execution of the flowchart shown in Fig. 6, the calculation unit 132 may perform the calculation shown in paragraphs 0055-0067 to calculate θ, and control the motor of the third rotation shaft provided on the flat plate portion 10 to tilt the flat plate portion 10 to the angle.

[0081] (3) The program for the beam antenna device 1 of the present disclosure to calculate the rotation angles of the first rotor 12 and the second rotor 14 based on the position of the flying object (HAPS) and control the angle of the beam antenna device 1 may be provided in a state stored in a computer-readable storage medium. The storage medium is capable of storing the program in a "non-transient tangible medium." The storage medium may include any suitable storage medium such as an HDD or SSD, or a suitable combination of two or more of these. The storage medium may be volatile, non-volatile, or a combination of volatile and non-volatile. Note that the storage medium is not limited to these examples, and may be any device or medium capable of storing the program.

[0082] The beam antenna device 1 can realize the functions of the multiple functional units shown in each embodiment by, for example, reading a program stored in a storage medium and executing the read program. The program may be provided to the beam antenna device 1 via any transmission medium (such as a communication network or broadcast waves). The beam antenna device 1 realizes the functions of the multiple functional units shown in each embodiment by, for example, executing a program downloaded via the Internet or the like. This program may be executed by the beam antenna device 1 or the like.

[0083] The program can be implemented using, for example, a scripting language such as ActionScript or JavaScript (registered trademark), an object-oriented programming language such as Objective-C, Java (registered trademark), or Python (registered trademark), or a markup language such as HTML5, but is not limited to these.

[0084] At least a part of the processing in the beam antenna device 1 may be realized by cloud computing consisting of one or more computers. Furthermore, each functional unit of the beam antenna device 1 may be realized by one or more circuits that realize the functions shown in the above embodiments, and the functions of multiple functional units may be realized by one circuit.

[0085] (4) According to each aspect of the present disclosure described above, a beam antenna device can be provided that provides communication services by performing uninterrupted beam tracking between a base station (HAPS) orbiting in the air, thereby contributing to the achievement of Goal 9 of the Sustainable Development Goals (SDGs) “Promote industry, innovation and infrastructure.” [Explanation of symbols]

[0086] 1 Beam antenna device 10 Flat plate part 11 First shaft 12 First rotating body 13 Second shaft 14 Second rotating body 15 Antenna installation section 16 Planar Antenna 100 HAPS 110 Communications Department 120 Input section 130 Control section 131 Acquisition Department 132 Calculation section 133 Drive control unit 140 Storage section 150 Drive unit 300 terminals

Claims

1. A flat plate portion, A first rotating body that rotates about a first axis perpendicular to the flat plate portion as a rotation axis and does not rotate permanently relative to the flat plate portion; A second rotating body having a second axis perpendicular to the first axis as a rotation axis; an antenna provided on the second rotor and having an antenna directivity in a fixed direction as viewed from the second rotor, the antenna being perpendicular to the second axis; A control unit that controls rotation of the first rotating body and the second rotating body; Equipped with The flat plate portion is inclined at a predetermined angle relative to the horizontal plane. Beam antenna device.

2. The beam antenna device directs antenna directivity toward an aircraft circling in the sky.

2. The beam antenna device according to claim 1.

3. The aircraft is a High Altitude Platform Station (HAPS).

3. The beam antenna device according to claim 2.

4. The beam antenna device is installed within a range vertically below the turning circle around which the HAPS turns.

4. The beam antenna device according to claim 3.

5. The installation angle of the beam antenna device is defined as (θ, ψ azimuth )year, θ is the angle of the plate part with respect to the horizontal plane, ψ azimuth is the azimuth angle, which is the rotation angle from true north to which the reference direction of the flat plate on the horizontal plane faces when true north is set to 0 degrees, The tilt limit angle is θ tilt_max , the limit angular velocity in the pan direction is ω pan_max year, When the relative position of the HAPS from the position of the beam antenna device at time t is (x(t), y(t), z(t)), [0010] In the above formula (1), Ry and Rz are rotation matrices and satisfy the following: [0025] [0030] From the formula (1), [0045] [0050] can be calculated, [006] [0070] The angle θ that satisfies the formulas (2) and (3) is set as the predetermined angle.

5. The beam antenna device according to claim 4.

6. The beam antenna device includes: An acquisition unit that acquires a current relative position (x, y, z) of the HAPS, The current relative position satisfies the following: [0080] The control unit is [0090] [0010] The rotation of the first rotating body and the second rotating body is controlled so as to satisfy the following:

6. The beam antenna device according to claim 5.

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