Beam controller, wireless communication device, beam control method, and program

Abstract

To provide a beam controller capable of suppressing the frequency of occurrence of fluctuations in reception level more than ever before.SOLUTION: A beam controller controls the direction of a receiving beam of a phased array antenna, and includes a tracking control unit that controls the direction of a first receiving beam for tracking a remote station, and a data reception control unit that controls the direction of a second receiving beam for receiving data from the remote station.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a beam controller, a wireless communication device, a beam control method, and a program.

Background Art

[0002] In vehicle stations for satellite communication, etc., in order to capture and track a counterpart station such as a satellite, while the antenna is being swung at a minute angle, the reception level is monitored, and the direction in which the reception level becomes the largest is detected, and there is one that uses conical scan to control the antenna in that direction (for example, see Patent Document 1).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the conventional conical scan, since the reception beam is frequently changed, there is a problem that fluctuations in the reception level accompanying the change may also frequently occur.

[0005] The present invention has been made in view of such circumstances, and provides a beam controller, a wireless communication device, a beam control method, and a program capable of suppressing the frequency of occurrence of fluctuations in the reception level more than in the conventional case.

Means for Solving the Problems

[0006] The present invention has been made to solve the above-described problems, and one aspect of the present invention is a beam controller that controls the direction of a reception beam of a phased array antenna, the beam controller including a tracking control unit that controls the direction of a first reception beam for tracking a counterpart station, and a data reception control unit that controls the direction of a second reception beam for receiving data from the counterpart station.

[0007] Also, another aspect of the present invention is the above-described beam controller, wherein the tracking control unit tracks the counterpart station using conical scanning based on the reception level of the first reception beam, and the data reception control unit sets the direction of the second reception beam in the direction of the rotation axis used for the conical scanning.

[0008] Also, another aspect of the present invention is a wireless communication device including a phased array antenna and a beam controller that controls the direction of a reception beam of the phased array antenna, the beam controller including a tracking control unit that controls the direction of a first reception beam for tracking a counterpart station, and a data reception control unit that controls the direction of a second reception beam for receiving data from the counterpart station.

[0009] Also, another aspect of the present invention is a beam control method for controlling the direction of a reception beam of a phased array antenna, the method including a first step of controlling the direction of a first reception beam for tracking a counterpart station, and a second step of controlling the direction of a second reception beam for receiving data from the counterpart station.

[0010] Also, another aspect of the present invention is a program for causing a computer to function as a beam controller that controls the direction of a reception beam of a phased array antenna, the beam controller including a tracking control unit that controls the direction of a first reception beam for tracking a counterpart station, and a data reception control unit that controls the direction of a second reception beam for receiving data from the counterpart station.

Advantages of the Invention

[0011] According to the present invention, the frequency of occurrence of fluctuations in the reception level can be suppressed more than before.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Modes for Carrying Out the Invention

[0013] Hereinafter, embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a schematic block diagram showing the configuration of a wireless communication device 10 according to an embodiment of the present invention. The wireless communication device 10 is, for example, an in-vehicle station or a terrestrial station for satellite communication, but may be other wireless communication devices. As shown in FIG. 1, the wireless communication device 10 includes an antenna 11, a beam generator 12, a data receiver 13, a reception level detector 14, and a beam controller 15 (beam control unit).

[0014] Antenna 11 is a phased array antenna in which a plurality of antenna elements are arranged in two-dimensional directions. In FIG. 1, eight antenna elements are shown, but the number of antenna elements is not limited to eight and may be other numbers such as 256 or 1024. Beam generator 12 branches the received signal of each antenna element of antenna 11 into two for data reception and for tracking the other station, and performs amplification and phase rotation for each branch. Beam generator 12 synthesizes the received signals that have been amplified and phase-rotated in the data reception branch of each antenna element. Also, beam generator 12 synthesizes the received signals that have been amplified and phase-rotated in the branch for tracking the other station of each antenna element. In this way, beam generator 12 generates a received beam for data reception and a received beam for tracking by synthesizing for each of the data reception and tracking branches. For example, a beam forming IC such as F6121 of RENESAS (registered trademark) may be used for beam generator 12.

[0015] Data receiver 13 performs reception processing such as demodulation on the received signal synthesized by beam generator 12 for data reception, and acquires the data indicated by the received signal. Reception level detector 14 detects the reception level of the received signal for tracking synthesized by beam generator 12.

[0016] Beam controller 15 controls the direction of the received beam of antenna 11. More specifically, beam controller 15 determines the gain value and phase value of amplification and phase rotation by beam generator 12 for each of the tracking and data reception of each antenna element based on the reception level detected by reception level detector 14, and sets the determined gain value and phase value in beam generator 12.

[0017] FIG. 2 is a schematic block diagram showing the configuration of beam controller 15 in the present embodiment. Beam controller 15 includes a tracking control unit 151 and a data reception control unit 152. Tracking control unit 151 controls the direction of a received beam for tracking (first received beam) for performing tracking of the other station. For example, tracking control unit 151 performs tracking of the other station using conical scanning based on the reception level RL of the received beam for tracking.

[0018] FIG. 3 is a schematic diagram for explaining the reception beams of the conical scan in the present embodiment. In the conical scan, the tracking control unit 151 sequentially sets a plurality of reception beams BR for tracking with a swing width θ from the rotation axis AR passing through the center of the antenna 11 at intervals φ between the reception beams, and obtains the reception level in each reception beam from the reception level detector 14. Then, the tracking control unit 151 determines the rotation axis AR of the next conical scan from these reception levels. For example, the tracking control unit 151 determines the rotation axis AR obtained by changing the direction of the reception beam with the largest reception level by a predetermined angle as the rotation axis AR of the next conical scan. The predetermined angle may be determined in advance or may be determined based on the value of the largest reception level. For example, the larger the value of the largest reception level, the smaller the predetermined angle may be set.

[0019] Returning to FIG. 2, the tracking control unit 151 determines the gain value G1 and phase value P1 for each of the plurality of reception beams for tracking determined by the rotation axis AR, swing width θ, and interval φ. The tracking control unit 151 sequentially sets the determined gain value G1 and phase value P1 of each reception beam to the beam generator 12. The tracking control unit 151 obtains the reception level RL in each of the plurality of reception beams for tracking from the reception level detector 14, and then determines at least the rotation axis AR of the next conical scan. The swing width θ and the interval φ may be predetermined values or may be changed based on the reception level RL. For example, the swing width θ may be set to a larger value as the difference in the reception levels RL of the plurality of reception beams for tracking in one conical scan is larger. Also, at least a part of the rotation axis AR, swing width θ, and interval φ may be determined based on the reception level of the reception beam for data reception. For example, the swing width θ may be set to a larger value as the reception level of the reception beam for data reception is smaller.

[0020] The data reception control unit 152 controls the direction of a reception beam (second reception beam) for data reception for receiving data from a counterpart station. The data reception control unit 152 sets the direction of the reception beam for data reception to the direction of the rotation axis AR used for the conical scan in the tracking control unit 151. The data reception control unit 152 sets the gain value G2 and the phase value P2 for the reception beam for data reception in the set direction to the beam generator 12.

[0021] FIG. 4 is a flowchart for explaining an operation example of the beam controller 15 in the present embodiment. First, the tracking control unit 151 of the beam controller 15 sets the rotation axis of the conical scan to an initial value (step Sa1). Next, the data reception control unit 152 of the beam controller 15 sets the direction of the reception beam for data reception to the direction of the rotation axis of the conical scan (step Sa2).

[0022] Next, when communication ends (step Sa3 - Yes), the beam controller 15 ends the process. When communication has not ended (step Sa3 - No), the tracking control unit 151 performs a conical scan using the rotation axis set in step Sa1 for the first time and the rotation axis set in step Sa5 described later for the second and subsequent times, and acquires the reception level (step Sa4). Next, the tracking control unit 151 determines the rotation axis of the next conical scan based on the reception level of the conical scan in step Sa4 (step Sa5), and returns to step Sa2.

[0023] In the above-described embodiment, the beam generator 12 branches the reception signals of the respective antenna elements of the antenna 11 into two for data reception and for tracking the counterpart station. However, the reception signals of some of the antenna elements of the antenna 11 may be branched into two for data reception and for tracking the counterpart station, and the reception signals of the remaining antenna elements may be used for data reception or for tracking the counterpart station. Further, the beam generator 12 may use the reception signals of some of the antenna elements of the antenna 11 for data reception and the reception signals of the remaining antenna elements for tracking the counterpart station.

[0024] Further, the present invention may also have the following embodiments. (1) One embodiment is a beam controller that controls the direction of a receiving beam of a phased array antenna, including a tracking control unit that controls the direction of a first receiving beam for tracking a counterpart station, and a data reception control unit that controls the direction of a second receiving beam for receiving data from the counterpart station.

[0025] Thereby, the beam controller can suppress the frequency of fluctuations in the reception level of the receiving beam for data reception more than before.

[0026] (2) Another embodiment is the beam controller according to (1), wherein the tracking control unit tracks the counterpart station using conical scanning based on the reception level of the first receiving beam, and the data reception control unit sets the direction of the second receiving beam in the direction of the rotation axis used for the conical scanning.

[0027] Thereby, since the swing range of the conical scan does not affect the reception level of the receiving beam for data reception, the tracking control unit can perform conical scanning in a wide scanning range with a large swing range to obtain high tracking performance.

[0028] (3) Another embodiment is a wireless communication device including a phased array antenna and a beam controller that controls the direction of a receiving beam of the phased array antenna, wherein the beam controller includes a tracking control unit that controls the direction of a first receiving beam for tracking a counterpart station, and a data reception control unit that controls the direction of a second receiving beam for receiving data from the counterpart station.

[0029] (4) Further, another embodiment is a beam control method for controlling the direction of a receiving beam of a phased array antenna, the method comprising: a first step of controlling the direction of a first receiving beam for tracking a counterpart station; and a second step of controlling the direction of a second receiving beam for receiving data from the counterpart station.

[0030] (5) Further, another embodiment is a program for causing a computer to function as a beam controller for controlling the direction of a receiving beam of a phased array antenna, the beam controller including a tracking control unit for controlling the direction of a first receiving beam for tracking a counterpart station and a data reception control unit for controlling the direction of a second receiving beam for receiving data from the counterpart station.

[0031] Alternatively, a program for realizing the functions of the beam controller 15 in FIG. 1 may be recorded on a computer-readable recording medium, and the beam controller 15 may be realized by causing the computer system to read and execute the program recorded on this recording medium. Here, the "computer system" shall include hardware such as an OS and peripheral devices.

[0032] Also, the "computer system" shall include a homepage providing environment (or a display environment) if the WWW system is being used. Furthermore, the "computer-readable recording medium" refers to portable media such as flexible disks, magneto-optical disks, ROMs, CD-ROMs, etc., and storage devices such as hard disks built into computer systems. Further, the "computer-readable recording medium" also includes those that dynamically hold a program for a short period of time, like a communication line when transmitting a program via a network such as the Internet or a communication line such as a telephone line, and those that hold a program for a certain period of time, like the volatile memory inside a computer system that serves as a server or client in that case. Also, the above program may be for realizing a part of the functions described above, or may be for realizing the functions described above in combination with a program already recorded in a computer system.

[0033] As described above, the embodiments of the present invention have been described in detail with reference to the drawings. However, the specific configuration is not limited to this embodiment, and design changes and the like within the scope not departing from the gist of the present invention are also included.

Explanation of Reference Numerals

[0034] 10 Wireless communication device 11 Antenna 12 Beam generator 13 Data receiver 14 Received level detector 15 Beam controller 151 Tracking control unit 152 Data reception control unit

Claims

1. A beam controller for controlling the direction of a reception beam of a phased array antenna, a tracking control unit for controlling the direction of a first reception beam for tracking a counterpart station, and a data reception control unit for controlling the direction of a second reception beam for receiving data from the counterpart station The beam controller comprising.

2. The tracking control unit tracks the counterpart station using conical scanning based on the reception level of the first reception beam, The data reception control unit sets the direction of the second reception beam in the direction of the rotation axis used for the conical scanning. The beam controller according to claim 1.

3. A phased array antenna, and a beam controller for controlling the direction of a reception beam of the phased array antenna The wireless communication device comprising. The beam controller is a tracking control unit for controlling the direction of a first reception beam for tracking a counterpart station, and a data reception control unit for controlling the direction of a second reception beam for receiving data from the counterpart station The wireless communication device comprising.

4. A beam control method for controlling the direction of a reception beam of a phased array antenna, a first step of controlling the direction of a first reception beam for tracking a counterpart station, and a second step of controlling the direction of a second reception beam for receiving data from the counterpart station The beam control method having.

5. A program for causing a computer to function as a beam controller for controlling the direction of a reception beam of a phased array antenna The program being, The beam controller is A tracking control unit that controls the direction of a first reception beam for tracking the other party's station, A data reception control unit that controls the direction of a second reception beam for receiving data from the other party's station, and A program comprising the above.

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