JP5748835B2 - Antenna device - Google Patents

Description

  The present invention relates to an antenna device capable of changing the direction of a main beam in the rotation direction of an FPU antenna.

  In the television broadcast outside the station, materials such as audio and video are transmitted to the base station by radio waves from an antenna of an FPU (Field Pickup Unit) which is a radio relay transmission device mounted on a moving body such as a helicopter. In the base station, radio waves from a moving body are received by an antenna of an FPU arranged on a steel tower or a rooftop. (For example, refer to Patent Document 1).

JP 2007-134915 A

Business communication is also performed between the mobile unit and the base station via a wireless communication line using an omnidirectional antenna. However, when the communication distance becomes long, the wireless communication line may not be established stably.
Therefore, an object of the present invention is to provide an antenna device that can stably maintain a wireless communication line between a mobile unit and a base station even when the communication distance is long.

The present invention controls the rotation angle of the turntable FPU antenna is arranged, an antenna device which is parallel in configured FPU to direct the FPU antenna in the direction of the communication target of the antenna, the rotation an array antenna are arranged a plurality of antenna elements at predetermined intervals along a circumference around the base of the rotational axis, based on the rotation angle of the pre-Symbol turntable, the direction of the beam directivity corresponding to the rotation angle The above-mentioned object is achieved by providing power supply control means for controlling power supply and non-power supply to each antenna element of the array antenna so that is realized.

The power supply control means includes, for example, an element selection means for selecting at least two adjacent power supply target antenna elements from the antenna elements of the array antenna based on the rotation angle of the turntable, and each power supply target antenna And a phase adjusting means for adjusting a power feeding phase for the element.

The element selection means can be configured to select the antenna element to be fed by a pin diode switch.
The present invention can further include an omnidirectional antenna and antenna switching means for switching between the omnidirectional antenna and the array antenna.
As the antenna element, a dipole antenna element, a double loop antenna element, or the like can be applied.

  According to the present invention, since the beam directivity in the direction corresponding to the rotation angle of the FPU antenna is realized, unnecessary radiation can be suppressed during transmission, and a stable received electric field can be ensured during reception. . In addition, an array antenna in which a plurality of antenna elements are arranged along a circumference centered on the rotation axis of the antenna turntable of the FPU is used, and the directivity of the array antenna is controlled based on the rotation angle of the FPU antenna. Therefore, it can be configured compactly and easily. Therefore, it is effective for business communication between a mobile unit and a base station during relay broadcasting.

It is a block diagram which shows one Embodiment of the antenna device which concerns on this invention. It is a side view which shows the structure of the array antenna in the antenna apparatus which concerns on this invention. It is sectional drawing by the AA line of FIG. It is a block diagram which shows the structural example of a directivity control part. It is the graph which illustrated the directivity of the array antenna.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an embodiment of an antenna device according to the present invention. The antenna apparatus AN according to the present embodiment is provided with an FPU (FieldPickupUnit) arranged as a radio relay transmission apparatus in a ground base station, and between this base station and a relay mobile body (such as a helicopter or a vehicle). It is used for business communication, and includes an array antenna 1, an omnidirectional antenna 3, a power feeding / phase switching unit 5, a directivity control unit 7, a radio device 9 and a remote control device 13.

As shown in FIG. 2, the array antenna 1 is disposed below the radome 15 of the FPU disposed on the steel tower. In the radome 15, an FPU antenna (not shown) and an FPU turntable 17 on which the FPU antenna is arranged are arranged. A mechanism for rotating the FPU turntable 17 is not shown.
FIG. 3 is a cross-sectional view taken along the line AA in FIG. As shown in FIG. 3, the array antenna 1 includes a cylindrical reflecting plate 19 and eight antenna elements 1 </ b> A to 1 </ b> H attached to the outer peripheral surface of the reflecting plate 19 via brackets 21. . The antenna elements 1 </ b> A to 1 </ b> H are arranged at equiangular intervals (45 ° intervals in the present embodiment) on the circumference around the rotation axis 23 of the FPU antenna turntable 17. As the antenna elements 1A to 1H, a dipole antenna element, a twin loop antenna element, or the like is used. A cylindrical cover 25 is disposed around the antenna elements 1A to 1H.

Next, the power feeding / phase switching unit 5 will be described. As shown in FIG. 4, the power feeding / phase switching unit 5 includes a distributor / combiner 27, switching units 29, 31, 33, 35, 37 and switching units 29 ′, 31 ′, 33 ′, 35 ′, 37 ′. I have.
The distributor / synthesizer 27 is connected to the directivity control unit 7 shown in FIG. 1 via a cable 47 and to the switching units 29 and 29 ′.
The switching unit 29 includes pin diode switches D1 and D2, the switching unit 31 includes pin diode switches D3 and D4, the switching unit 33 includes pin diode switches D5 and D6, and the switching unit 35 includes pin diode switches D7 and D8. However, the switching unit 37 is provided with pin diode switches D9 and D10, respectively. Between the switching units 29 and 31, coaxial cables 39 and 41 for phase adjustment are provided. The length of the coaxial cable 39 is set so that the phase amount with respect to the passing high-frequency signal is 0 °, and the length of the coaxial cable 41 is set so that the phase amount is −110 °. Has been.

Since the switching units 29 ′, 31 ′, 33 ′, 35 ′, and 37 ′ have the same configuration as the switching units 29, 31, 33, 35, and 37, description thereof is omitted.
The switching unit 35 is connected to the antenna element 1A and the antenna element 1C via the arrester 43, and the switching unit 37 is connected to the antenna element 1E and the antenna element 1G via the arrester 43.
On the other hand, the switching unit 35 ′ is connected to the antenna element 1B and the antenna element 1D via the arrester 43 ′, and the switching unit 37 ′ is connected to the antenna element 1F and the antenna element 1H via the arrester 43 ′.

Next, the operation of the antenna device according to this embodiment will be described.
In FIG. 1, the FPU receiver 4 is connected to an FPU antenna (not shown), and the rotation control unit 11 is connected to an FPU turntable 17.

The FPU receiver 4 is based on radio waves from the relay mobile body received by the FPU antenna, that is, radio waves including position data (GPS data) of the relay mobile body and radio waves including material data such as audio and video. Then, the position data and the material data are acquired, and the position data is output to the rotation control unit 11. The rotation control unit 11 calculates the azimuth of the relay moving body in the horizontal plane viewed from the FPU antenna based on the position data and data indicating the FPU antenna arrangement position known in advance, and based on the azimuth, the FPU antenna The rotation angle of the FPU antenna turntable 17 is controlled so that is directed toward the relay moving body.
As a result, the FPU antenna continuously receives radio waves for materials such as audio and video transmitted from the moving body while tracking the relay moving body.

  The directivity control unit 7 inputs the rotation angle of the FPU antenna turntable 17 indicating the azimuth of the moving body from the rotation control unit 11, and feeds and phase for realizing the beam directivity in the direction corresponding to the rotation angle. A control signal is output to the power feeding / phase switching unit 5 via the cable 45. Therefore, the feeding / phase switching unit 5 selects two adjacent feeding target antenna elements from the antenna elements 1A to 1H of the array antenna 1 and adjusts the feeding phase for the selected antenna elements.

  That is, when the rotation angle of the FPU antenna turntable 17 indicating the direction of the relay moving body is, for example, 0 ° shown in FIG. 5 or the vicinity thereof, the directivity control unit 7 switches the pin diode switches D2, D4 of FIG. , D 5, D 7, D 1 ′, D 3 ′, D 5 ′, and D 7 ′ are output to the power feeding / phase switching unit 5. In this case, the antenna elements 1A and 1B are selected as the antenna elements to be fed, the phase amount of the signal for the antenna element 1A is adjusted by the coaxial cable 41, and the phase amount of the signal for the antenna element 1B is coaxial. Adjusted by cable 39 '. As a result, the combined directivity as shown by the solid line in FIG. 5, that is, the beam directivity in the direction corresponding to the rotation angle of the FPU antenna turntable 17 is realized by the antenna elements 1A and 1B.

  On the other hand, when the rotation angle of the FPU antenna turntable 17 indicating the direction of the relay moving body is, for example, 22.5 ° shown in FIG. 5 or the vicinity thereof, the directivity control unit 7 sends the pin diode switch D1 shown in FIG. , D3, D5, D7, D1 ′, D3 ′, D5 ′, and D7 ′ are output to the power supply / phase switching unit 5. In this case, the antenna elements 1A and 1B are selected as the antenna elements to be fed, the phase amount of the signal for the antenna element 1A is adjusted by the coaxial cable 39, and the phase amount of the signal for the antenna element 1B is coaxial. Adjusted by cable 39 '. As a result, the antenna elements 1A and 1B realize the combined directivity as shown by the dotted line in FIG. 5, that is, the beam directivity in the direction corresponding to the rotation angle of the FPU antenna turntable 17.

  Thus, in this embodiment, two adjacent antenna elements 1A to 1H of the array antenna 1 are controlled by the on / off control of the pin diode switches D1 to D10 and D1 ′ to D10 ′ by the control signal from the directivity control unit 7. A set of antenna elements (1A, 1B), (1B, 1C), (1C, 1D), (1D, 1E), (1E, 1F), (1F, 1G), (1G, 1H), (1H , 1A) and the phase amount for each set of antenna elements is selected.

  The directivity control unit 7 incorporates a memory that stores on / off control data of the pin diode switches D1 to D10 and D1 ′ to D10 ′ corresponding to a plurality of rotation angle ranges of the FPU antenna turntable 17, and rotates the FPU antenna. The diode switch on / off control data corresponding to the angle range including the rotation angle of the table 17 is read from this memory and output to the power feeding / phase switching unit 5 as a control signal. Note that the phase amount of the coaxial cables 39 and 41 can be determined by simulation.

When the array antenna 1 is used as a transmission antenna, high-frequency power (for example, having a center frequency of 400 MHz) output from the radio device 9 in FIG. 1 is fed / phase switched via the directivity control unit 7 and the cable 47. It is supplied to the distributor / synthesizer 27 of the unit 5. Therefore, business communication radio waves are transmitted from the antenna elements selected by the on / off control of the pin diode switches D1 to D10 and D1 ′ to D10 ′ toward the relay mobile body.
On the other hand, when the array antenna 1 is used as a receiving antenna, the received signal (business communication signal from the relay mobile body) by the selected antenna element is transmitted to the distributor / combiner 27 of the power feeding / phase switching unit 5 and the directivity control. The signal is input to the wireless device 9 via the unit 7.

The directivity control unit 7 also executes the following processing. In other words, the direction in which transmission / reception by the array antenna 1 is hindered by a mountain shade or surrounding buildings is known in advance. Therefore, when the rotation angle of the FPU antenna turntable 17 is in an angle range in the direction in which the transmission / reception is hindered, a process of switching the array antenna 1 to the omnidirectional antenna 3 is executed to stably maintain communication. .
It is also possible to instruct the remote control device 13 whether to switch between the array antenna 1 and the omnidirectional antenna 3 manually or automatically.

  On the other hand, the radio device 9 also executes processing for acquiring the position data from the radio wave including the position data from the relay mobile body received by the array antenna 1 and transmitting the data to the rotation control unit 11. The rotation control unit 11 executes a process of substituting the position data from the wireless device 9 acquired via the modem 11a when the position data from the FPU receiver 4 is interrupted for some reason, thereby tracking operation. Is maintained.

The present invention is not limited to the above embodiment, and can include various modifications. An example is shown below.
(A) In the embodiment, not only the antenna element is selected but also the phase amount is selected. However, the embodiment can be implemented only by selecting the antenna element.
(B) The present invention can be applied not only to a base station but also to a relay mobile unit. Of course, the present invention can be applied to both the base station and the relay mobile unit.
(C) The number of antenna elements of the array antenna 1 can be increased in order to improve electrical performance (directivity, gain, etc.). In that case, the number of coaxial cables for defining the phase amount is also increased as necessary.
(D) It is also possible to adjust the phase amount using a phase shifter.
(E) It is also possible to use a coaxial switch instead of the pin diode switch.
(F) In the embodiment, two adjacent antenna elements are selected as the power supply target antenna elements, but it is also possible to configure to select three or more adjacent antenna elements as the power supply target antenna elements. .

DESCRIPTION OF SYMBOLS 1 Array antenna 1A-1H Antenna element 3 Non-directional antenna 4 FPU receiver 5 Feeding / phase switching part 7 Directivity control part 9 Radio 11 Rotation control part 13 Remote control device 15 Radome 17 FPU turntable 19 Reflecting plate 21 Bracket 23 Rotation axis 25 Cover 27 Distributor / Synthesizer 29, 31, 33, 35, 37 Switching unit 29 ', 31', 33 ', 35', 37 'Switching unit D1-D10 Pin diode switch D1'-D10' Pin diode switch 39, 41, 39 ', 41' coaxial cable 43, 43 'arrester 45, 47 cable

Claims (5)

An antenna device attached to an FPU configured to control a rotation angle of a turntable on which an FPU antenna is disposed and to direct the FPU antenna toward a communication target antenna ,
An array antenna are arranged a plurality of antenna elements at predetermined intervals along a circumference around the turntable axis of rotation,
Based on the rotational angle of the front Symbol turntable, and power supply control means for controlling feeding, an unpowered for each antenna element of said array antenna so that the beam directivity of the direction corresponding to the rotation angle is achieved,
An antenna device comprising: The power supply control means includes
Element selecting means for selecting at least two power feeding target antenna elements adjacent from the antenna elements of the array antenna based on the rotation angle of the turntable;
Phase adjusting means for adjusting a feeding phase for each of the feeding target antenna elements;
The antenna device according to claim 1, further comprising:   The antenna device according to claim 2, wherein the element selection unit is configured to select the antenna element to be fed by a pin diode switch.   The antenna apparatus according to any one of claims 1 to 3, further comprising an omnidirectional antenna, and antenna switching means for switching between the omnidirectional antenna and the array antenna.   The antenna device according to claim 1, wherein the antenna element is a dipole antenna element or a twin loop antenna element.

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