JPH09139623A - Satellite broadcasting reception antenna - Google Patents

Abstract

PROBLEM TO BE SOLVED: To easily catch radio waves in a short time by providing a 1st mechanical means fitted on the back of a reflection mirror and a 2nd mechanical means for varying the spatial position and direction of a primary radiator. SOLUTION: A reflection mirror 1 performs the reflection and convergence of radio waves coming from a static satellite and is composed of one part of spherical surface or rotary paraboloid composed of FRP or the like. Then, at the 1st mechanical means, a section 2 fixed on the back of the reflection mirror by rivets or screws consists of the 1st mechanical means together with a section 3 and a screw 4 not fixed on the reflection mirror 1 and while inserting the entire antenna including the reflection mirror 1 into an antenna supporting pole 9, only an azimuth angle can be adjusted with that pole 9 as an axis. Besides, a 2nd mechanical means 6 for changing the spatial position and direction of the primary radiator is installed at the primary radiator or a low noise converter and fixed on a supporting arm 8 fitted through a screw 7 to the 1st mechanical section.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a satellite dish for use at microwave frequencies.

[0002]

2. Description of the Related Art Conventionally, a satellite broadcasting receiving antenna used at a microwave frequency is a reflecting mirror (hereinafter referred to as a parabolic reflecting mirror) formed by a part of a paraboloid of revolution that reflects and converges an incoming radio wave from a satellite. And a primary radiator arranged in the vicinity of the focal point thereof, a first mechanical means for fixing the primary radiator, and a first radiator mounted on the back surface of the parabolic antenna reflecting mirror for fixing the respective parts to the antenna support pole. It consisted of two mechanical means.

The second of these mechanical means has a so-called biaxial adjustment function capable of adjusting two angles such that the parabolic reflector can be made to match the azimuth angle and the elevation angle direction of the radio wave coming from the geostationary satellite. Was.

[0004]

As described above, in the conventional antenna, it is necessary to provide the mechanical means attached to the back surface of the parabolic reflector with the biaxial adjustment function of the azimuth angle and the elevation angle, and at the same time, to adjust those angles to the external force. It is necessary to fix it with a mechanical strength that can withstand, and compared with general outdoor equipment attached to VHF or UHF antennas and road sign poles,
There are problems such as (1) it is difficult to capture satellite radio waves because there are two angles to be adjusted, (2) it is heavy and bulky, and (3) materials and processing are expensive. The present invention solves such a conventional problem.

[0005]

In order to solve the above-mentioned problems, the above-mentioned mechanical means has a uniaxial structure in which the elevation angle of the reflecting mirror is fixed to a certain standard value and only the azimuth angle can be adjusted. It is possible to have a simple structure similar to the general pole mounting device as described above.

However, the elevation angle of the radio wave coming from the geostationary satellite and the elevation angle of the reflecting mirror do not generally match, and if the elevation angle of the reflecting mirror is fixed, it will enter the reflecting mirror as an off-axis incident electric wave. , The focusing point is spatially displaced from the regular focusing point of the reflecting mirror by a distance according to the off-axis angle.

Therefore, the conventional mechanical means for changing the spatial position and orientation of the primary radiator (that is, the irradiation direction of the primary radiator), which has been fixed to the regular focusing point, by the amount of displacement according to the elevation angle is conventionally available. By replacing it with the mechanical means for fixing, it is possible to obtain a performance almost equivalent to that of the conventional antenna.

Here, "almost" means that when the reflecting mirror is a parabolic reflecting mirror (Claim 2), the antenna gain decreases with an increase in the off-axis angle. If the corners are too large, the antenna of the present invention may cause performance problems.

In order to solve this problem, the present invention uses a part of the spherical surface as a reflecting mirror instead of the parabolic reflecting mirror (in the case of claim 3) to increase the off-axis angle and suppress a decrease in antenna gain. The purpose is to

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The invention according to claim 1 of the present invention is the first mechanical means mounted on the back surface of a reflecting mirror for reflecting and focusing the radio waves coming from a geostationary satellite and the focusing point of the reflecting mirror. A satellite broadcast receiving antenna comprising a second mechanical means capable of varying the spatial position and orientation of a primary radiator arranged in the vicinity thereof, wherein the first mechanical means does not have an elevation angle adjusting function. It is a broadcast receiving antenna and has the following functions.

That is, although the reflector of the antenna attached to the antenna support pole by the first mechanical means is fixed at a designed elevation angle, the incoming radio waves from the geostationary satellite are reflected by the above-mentioned reflection. The mirror focuses the most received power on one point in space. Since the focal point is spatially displaced according to the elevation angle of the incoming radio wave, the spatial position and orientation of the primary radiator can be varied by the second mechanical means to obtain the maximum received power. If the spatial position and the direction of the primary radiator are set in advance to the position of the maximum received power according to the elevation angle of the incoming radio wave, the azimuth angle with the antenna support pole as the rotation axis by the second mechanical means. The structure is such that the maximum received power of incoming radio waves can be obtained simply by adjusting.

The invention according to claim 2 of the present invention is a satellite broadcast receiving antenna in which the reflecting mirror according to claim 1 is a part of a paraboloid of revolution, and the incident direction of the incoming radio wave to the reflecting mirror is the reflecting mirror. As the spatial distance from the focal point of the paraboloid of revolution increases as the focal point of the incoming radio wave increases, the amount of decrease in antenna gain also increases. And the same effect as that of the first aspect.

The invention according to claim 3 of the present invention is a satellite broadcasting receiving antenna in which the reflecting mirror in claim 1 is a part of a paraboloid of revolution, and in addition to the operation of claim 1 described above,
This has the effect of suppressing a decrease in antenna gain related to the elevation angle of the incoming radio wave that occurs when the reflecting mirror is a paraboloid of revolution.

Hereinafter, an embodiment of the present invention will be described with reference to FIG.
Will be explained. (Embodiment) FIG. 1 shows an elevation view and a partial explanatory view showing an embodiment of the present invention.

In FIG. 1, reference numeral 1 is called a reflecting mirror,
It has a function of reflecting and converging radio waves coming from a geostationary satellite, and is composed of a part of a spherical surface or a paraboloid of revolution made of metal such as aluminum or FRP having a radio wave reflecting material embedded therein.

Reference numeral 2 denotes a portion of the first mechanical means fixed to the back surface of the reflecting mirror 1 by a rivet or a screw, and constitutes a first mechanical means together with a portion 3 not fixed to the reflecting mirror 1 and a screw 4. , The whole antenna including the reflector is sandwiched between the antenna support poles 9 as shown in the partial plan view in the figure, and only the azimuth angle can be adjusted with the pole as an axis. The function of adjusting the elevation angle, which had been used, is eliminated and the structure is simplified to a uniaxial structure.

In the primary radiator 5 and the low noise converter of the antenna, since the focusing point of the radio wave changes according to the elevation angle (θ in the figure) of the incoming radio wave, the spatial position and direction of the primary radiator are changed. Second mechanical means 6 is provided in said primary radiator or low noise converter, the AA of FIG.
As shown in cross section, it is fixed by screws 7 to a support arm 8 attached to the first mechanical part.

The second mechanical means 6 is a prismatic member provided with a plurality of pairs of holes for changing the spatial position.
In order to change the above-mentioned direction, a polygonal line is formed as shown.

A second mechanical means for continuously changing the spatial position and orientation may be provided.

[0020]

As described above, in the satellite broadcast receiving antenna of the present invention, if the spatial position and orientation of the primary radiator corresponding to the elevation angle of the radio wave coming from the geostationary satellite are set,
After attaching to an antenna support pole like a general outdoor device that can be attached to a pole, radio waves can be captured simply by rotating and adjusting the azimuth angle around the pole, so conventional satellite broadcast receiving antennas can be used in elevation and azimuth directions. Compared to searching for the arrival direction of radio waves while adjusting both angles, it becomes much easier to capture radio waves in a shorter time, and at the same time, it is possible to have a mechanically simple structure and reduce weight. There is a great industrial value that the processing cost can be reduced.

[Brief description of the drawings]

FIG. 1 is an elevation view of a satellite broadcast receiving antenna according to an embodiment of the present invention.

FIG. 2 is an elevation view of a conventional satellite broadcast receiving antenna.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Reflector (part of a rotating parabolic surface or a spherical surface) 2, 3, 4 First mechanical means 5 Primary radiator 6, 7 Second mechanical means 8 Primary radiator and low noise converter support arm 9 Antenna Support pole

Claims (3)

[Claims] 1. Spatial position and orientation of first mechanical means attached to the rear surface of a reflecting mirror for reflecting and focusing the radio wave coming from a geostationary satellite and a primary radiator arranged near the focusing point of the reflecting mirror. A satellite broadcast receiving antenna having a second mechanical means capable of changing the above, wherein the first mechanical means has no elevation angle adjusting function. 2. The satellite broadcast receiving antenna according to claim 1, wherein the reflecting mirror is a part of a paraboloid of revolution. 3. The satellite broadcast receiving antenna according to claim 1, wherein the reflecting mirror is a part of a spherical surface.