JPH05167328A - Antenna mount - Google Patents

Abstract

PURPOSE:To eliminate the follow-up delay in spite of simple structure and compact size and low in cost by executing the control of two shafts with regard to only directional control to a tracking object, or only with regard to one direction in the horizontal direction of oscillation in order to always hold the directivity of an antenna in the same direction. CONSTITUTION:To a rack base 22 fixed to a marine vessel 21, an AZ shaft 23 being vertical to the marine vessel 21 is attached so as to be freely turnable, and to the frame 23a, an El shaft 24 being parallel to the marine vessel 21 is attached so as to be freely turnable, and an antenna 25 is fixed thereto. The antenna 25 is constituted in advance of a reflecting plate 25a having at least three or more pieces of radiation quantities 25b, the shaft 23 is subjected to turning control by using an antenna mounting controller 26 so that the shaft 24 intersects orthogonally with the azimuth of a satellite, and the shaft 24 is subjected to turning control so that the antenna 25 becomes an elevation angle directed in the satellite direction. However, since the antenna 25 is shifted sometimes due to the rolling and the pitching of the marine vessel 21, an oscillation detector 27 for detecting two inclinations intersecting orthogonally with the plane of the marine vessel is provided, a beam controller 29 is operated by an oscillation controller 28 and an oscillation correcting signal is outputted therefrom.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an antenna mount for always keeping the pointing direction of an antenna in the same direction.

[0002]

2. Description of the Related Art For example, a satellite communication antenna for a ship is designed to always direct the antenna in the direction of a satellite (tracking target) irrespective of the movement of the ship over the ocean, the change in the bow direction, the rolling of the ship, the pitching, etc. , It is necessary to control the attitude of the antenna with the antenna mount.

There are 2 to 4 axis systems for satellite communication antenna mounts for mobile bodies such as ships. Hereinafter, a typical method of 2 to 4 axes will be described.

In the four-axis system, as shown in FIG. 7, a pedestal 2 is provided perpendicular to a mounting surface (hereinafter referred to as a ship) 1 such as a deck of a ship.
Is fixed, an X axis 3 is rotatably provided on the gantry 2, a Y axis 4 is rotatably provided on the X axis 3, and an Az axis 5 is rotatably provided on the Y axis 4. An El shaft 6 is rotatably provided on the shaft 5, and an antenna 7 is fixed to the El shaft 6.
Then, the X axis 3 is rotated to correct the attitude of the ship 1 with respect to rolling, the Y axis 4 is rotated to correct the attitude with respect to pitching, and the Az axis 5 is rotated to direct the direction to the satellite. Then, the El axis 6 is rotated to maintain the elevation angle with respect to the satellite, and the antenna 7 is always directed regardless of the movement of the ship 1 on the sea, the change in the bow direction, rolling, swaying due to pitching, and the like. It is held in the direction of the satellite.

In the triaxial direction, as shown in FIG.
The pedestal 2 is rotatably provided with an Az axis 8, the Az axis 8 is rotatably provided with an X axis 9, and the X axis 9 is rotatably provided with El.
The shaft 10 is provided, and the antenna 7 is fixed to the El shaft 10. The Az axis 8 is rotated to direct the direction to the satellite, the X axis 9 is rotated to correct the attitude of the ship 1 with respect to rolling, and the El axis 10 is rotated to correct the attitude with respect to pitching. The antenna 7 is always held in the direction of the satellite regardless of the movement of the ship 1 over the ocean, the change in the bow direction, the rolling, the shaking due to pitching, and the like.

However, in such a 4-axis type and 3-axis type antenna mount, since the rotation control amount of each axis does not require complicated calculation such as coordinate conversion, control of each axis is easy. Although many have been used conventionally, there are drawbacks that the structure is complicated, the cost is large, and the size is large due to the large number of shafts.

In the two-axis system, as shown in FIG.
An Az shaft 11 perpendicular to the pedestal 2 is rotatably provided.
An Az-El type in which an El shaft 12 is rotatably provided on the z axis,
As shown in FIG. 10, a horizontal X-axis 13 is rotatably provided on the gantry 2, and a Y-axis 14 is rotatably provided on the X-axis 14.
-There is a Y type.

[0008]

However, although such a two-axis type antenna mount has the advantages of a much simpler structure, smaller size, and lower cost, the two-axis type antenna mount can be used for both motion compensation and satellite pointing correction. Since both are performed, there is a problem that control must be performed based on a complicated operation involving extremely complicated coordinate conversion.

Further, in the two-axis system, there is a problem that the rotational speed of each axis for the motion correction is increased. In particular, when the satellite is located at a high elevation angle, in the Az-El system of FIG. 9, the antenna 7 cannot be oriented in the satellite direction unless the two axes are rotated at extremely high speed according to the shaking of the ship 1.
There is a problem of tracking delay that the shaking direction can not catch up,
In the XY system shown in FIG. 10, the tracking delay problem occurs at a low elevation angle.

It is an object of the present invention to provide an antenna mount which does not cause such a tracking delay problem even though the structure is a simple and inexpensive two-axis system.

[0011]

In order to solve the above-mentioned problems, in the antenna mount of the present invention, in a two-axis antenna mount, only the pointing control to the tracking target is performed by the two axes, and the motion compensation for the tracking target is performed. Is performed by controlling the beam of the antenna, or the directional control of the tracking target and the correction of the sway to the tracking target in one lateral direction are performed by the two axes to correct the sway of the tracking target in a direction orthogonal to the one direction. The beam is controlled by the antenna.

[0012]

In this way, since the two axes can be controlled only by controlling the pointing of the object to be tracked or in one lateral direction of the vibration, the control by complicated calculation as in the prior art is not required. It becomes unnecessary.

[0013]

Embodiments of the present invention will be described below with reference to the drawings.

1 and 2 show an embodiment of the present invention.

FIG. 1 shows an Az-El type biaxial antenna mount, in which a Az shaft 23 perpendicular to the ship 21 is rotatably attached to a pedestal 22 fixed to the ship 21. Has been. An El shaft 24 parallel to the ship 21 is rotatably attached to the frame 23a of the Az shaft 23. An antenna 25 is fixed to the El shaft 24. The antenna 25 includes a reflection plate 25a and a plurality of (at least three or more) radiators 25b fixed to the reflection plate 25a.

The Az axis 23 is rotationally controlled by the antenna mount controller 26 so that the El axis 24 is orthogonal to the azimuth of the satellite, and the El axis 24 has an elevation angle at which the antenna 25 is oriented in the satellite direction. The rotation is controlled.

Thus, in this way, the Az axis 23 and El
Even if satellite pointing control is performed on the axis 24, the antenna 25 is displaced from the satellite direction due to the rolling and pitching of the vessel 21.

The vessel 21 is provided with a sway detector 27 for detecting two lateral inclinations of the plane of the vessel 21 which are orthogonal to each other due to rolling and pitching of the vessel 21. Upon receiving this signal, the motion controller 28 outputs a motion compensation control signal for the vertical component and the horizontal component to the antenna beam controller 29.

The antenna beam controller 29 includes a plurality of in-phase power distributors, and changes the phase of power distribution to the radiators corresponding to the respective power distributors in accordance with the control signal, thereby changing the phase from the position shown in FIG. By rolling and pitching, the antenna 25 moves the antenna beam by a deviation from the direction of the satellite S as shown in FIG. 4, so that the antenna beam is always directed in the direction of the satellite S regardless of the shaking of the ship 21. The direction of the antenna beam may be continuously swung, or may be swung stepwise instead of continuously.

[0020]

Other Embodiments FIGS. 5 and 6 show another embodiment of the present invention.

In this embodiment, a plurality of radiators 25b are arranged only in a horizontal row, and the motion controller 38 outputs a motion compensation control signal of the vertical component to the antenna mount controller 36. The antenna mount controller 36 has the Az axis 2
3. The satellite axis control of the El shaft 24 is performed, and in response to the sway of the ship 1, the sway in the lateral direction is canceled by the sway correction control signal of the vertical component El.
The shaft 24 is rotated.

Then, only the motion compensation control signal of the vertical component is output from the motion controller 38 to the antenna beam controller 39, and the antenna beam controller 39 oscillates the antenna beam only in this vertical direction to direct it to the satellite. To be made.

In the above embodiment, only the Az-El system is illustrated, but it goes without saying that the present invention can be applied to the XY system.

[0024]

Since the antenna mount of the present invention is constructed as described above, it has a simple structure, a small size, and a low cost.
Despite the axis system, simple two-axis rotation control is sufficient, tracking delay can be prevented, and the antenna can be aimed at the tracking target regardless of fast shaking.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing a mechanism unit according to an embodiment of the present invention.

FIG. 2 is a configuration diagram showing a control unit of the embodiment shown in FIG.

FIG. 3 is a diagram illustrating the principle of the present invention.

FIG. 4 is a diagram illustrating the principle of the present invention.

FIG. 5 is a schematic perspective view showing a mechanism portion according to another embodiment of the present invention.

6 is a configuration diagram showing a control unit of the embodiment shown in FIG.

FIG. 7 is a principle view showing a conventional 4-axis type antenna mount.

FIG. 8 is a principle view showing a conventional 3-axis type antenna mount.

FIG. 9 is a principle view showing a conventional biaxial antenna mount.

FIG. 10 is a principle view showing a conventional biaxial antenna mount.

[Explanation of symbols]

 21 Ship 22 Stand 23 Az axis 24 El axis 25 Antenna 26 Antenna mount controller 27 Motion detector 28 Motion controller 29 Antenna beam controller 36 Antenna mount controller 37 Motion detector 38 Motion controller 39 Antenna beam controller

Claims (2)

[Claims] 1. An antenna mount having a two-axis structure, wherein only the pointing control to the tracking target is performed by the two axes, and the fluctuation of the tracking target is corrected by the beam control of the antenna. 2. An antenna mount having a two-axis structure, wherein the two axes are used to control the pointing of the tracking target and correct the lateral motion of the motion of the tracking target so as to be orthogonal to the one direction of the motion of the tracking target. An antenna mount characterized in that direction correction is performed by controlling the beam of the antenna.