JPS6177404A - Reception antenna for simple satellite broadcast - Google Patents

Abstract

PURPOSE:To attain ease of antenna installation with simple structure by opposing two reflecting plates having a shape bent along with a parabola in the state that the parabolas are crossed together. CONSTITUTION:Since the 1st reflecting plate 2 has a shape that only one axis is bent along the parabola, the focus is a linear focus. The 2nd reflection plate 3 bent to be crossed with the parabola of the 1st reflecting plate 2 exists at the position of the linear focus. Thus, the focus by the 2nd reflecting plate 3 is a linear focus, but since both the linear foci are crossed, dotted focus is attained at the crossed part. When the primary horn 4 is placed to said part, a radio wave is collected and received. The structure is simplified in this way and ease of antenna installation is attained.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a receiving antenna for satellite broadcasting, and particularly to a simple type antenna.

[Conventional technology]

As a satellite broadcast receiving antenna, a parabolic antenna having a parabolic reflector (1) as shown in FIG. 4 is usually used. However, even though the diameter of the parabolic reflector is small, it is relatively difficult to realize this parabolic antenna by integrally molding it because the parabolic surface changes over time, and for this reason, mass production is difficult. It's not worth it and it's expensive. Moreover, this parabolic reflector is 2m long.
When it comes to large objects, such as ~5m, it is almost impossible to construct the parabolic surface with a single plate. Conventionally, the parabolic surface is divided into segments, and each segment is made up of multiple plates. They are joined together and fixed with bolts, for example, to form a single parabolic reflector that can be used as an antenna.

[Problem that the invention seeks to solve]

However, such conventional parabolic antennas have the disadvantage that it takes a lot of time and effort to create the parabolic reflector, and the cost is high. In addition, if the antenna is large and it is difficult to create a parabolic reflector at the location where the antenna is installed, the created parabolic antenna itself must be transported and stored. Another drawback is that special construction is required when installing the antenna.

[Means for solving problems]

In the above invention, instead of using a parabolic reflector, a first reflector (2) having a shape bent along a parabola along only one axis, and a position facing the first reflector, and A second reflector (3) bent along a parabola that intersects with the parabola of the first reflector is provided at the focal point of the first reflector. ) is collected by the primary horn (4) to capture the radio waves.

[Effect]

The first reflecting plate (2) is a flat plate bent along a parabola along only one axis, so its focal point is a linear focal point,
Since there is a second reflector (3) bent so as to intersect the parabola of the first reflector (2) at the position of the linear focal point, this second reflector (3) The focal point is also a linear focal point, but since the two linear focal points intersect, the intersection becomes a point focal point, and if the primary horn (4) is installed in this area, the primary horn (4) ) where radio waves are collected and received.

〔Example〕

FIG. 1 shows an embodiment of the present invention, in which (2) is a first reflecting plate, (3) is a second reflecting plate, (4) is a primary horn, and (5) is a primary horn. 5HF- for converting SHF radio waves taken in from this primary horn (4) into UHF signals.
It is a UHF converter.

In this case, the focus of the first reflector becomes a linear focus F as shown in FIG. 3, and the second reflector (
3) is arranged to face the first reflecting plate (2).

The first and second reflecting plates (2) and (3) can be configured, for example, as follows.

That is, Fig. 2 is an example of one of the reflective plates, which is made by curving two parallel beams (11) and (12), and attaching a metal sheet, such as aluminum foil, to the curved beams (11 and 12). (13) etc. to these two beams (11)
(12) Form a reflective plate (21, +31) in the shape of a flat plate bent along a parabola by stretching it between them.In this case, the wires (11) and (12) are shaped in advance However, it is also possible to maintain the curved shape by connecting both ends of the curved shape with, for example, thread or wire (14) as shown in the figure.

In this case, the first reflector (2) and the second reflector (
3) have different sizes, the first reflector (2) mainly receives direct radio waves from the satellite, reflects them to the second reflector (3), and the second reflector (3) 3), the second reflector (3) may be smaller in size than the first reflector (2).

Further, in this example, the parabola of the first reflecting plate (2) and the parabola of the second reflecting plate (3) are arranged so as to be perpendicular to each other. If arranged like this, both reflections h
(Radio waves will gather at the point where the linear focal points of 21 (31) intersect, and if a primary horn (4) is installed at that point, it will be efficient (radio waves will gather at one horn (4)) be.

If you do not use a curved beam as in the example in Figure 2, but instead curve a straight beam when installing the antenna, tie both ends with wire or the like to maintain the curvature. ,
Basically, two reflectors can be constructed using aluminum foil and four beams, which is convenient for non-electronic transportation of the antenna.

Note that instead of using the beam and the metal sheet as in the example shown in the figure, a mirror-finished metal thin plate may be used and this may be curved.

Furthermore, if the antenna is of an offset type, the curved surface of one reflector will be smaller than the example shown in the figure, making it easier to manufacture.

〔Effect of the invention〕

According to this invention, instead of using a parabolic reflector,
Two reflecting plates bent along a parabola are placed opposite each other in such a way that their parabolas intersect, and a point focal point is formed at the intersection of the linear focal points of these two reflecting plates.
Since a secondary horn is provided to collect radio waves on this primary horn, the configuration is simple and non-electrical, and the antenna can be easily installed.

In addition, the two reflectors can be made by bending a flat plate along a parabola along only one axis, so it can be realized by bending the plate in the parabola shape when manufacturing the antenna. Therefore, when transporting the antenna, it is necessary to use a flat plate Since all you have to do is transport the antenna, even if you are making a large antenna, it will be much easier to transport it.

[Brief explanation of drawings]

FIG. 1 is a diagram showing the configuration of an example of a satellite broadcast receiving antenna according to the present invention, FIG. 2 is a diagram showing an example of its essential parts, FIG. 3 is a diagram for explaining the invention, and FIG. 1 is a diagram showing an example of a conventional satellite broadcast receiving parabolic antenna. (2) is the first reflector, (3) is the second reflector, (4)
is the primary horn.

Claims (1)

[Claims] A first reflecting plate bent along a parabola on only one axis, and a second reflecting plate bent along a parabola intersecting the parabola at the line focal point of the first reflecting plate. A simple satellite broadcast receiving antenna comprising a reflecting plate facing the first reflecting plate.