JPH0727688Y2 - Microwave reflector - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial field of application] The present invention is used for microwave radio communication.

The present invention relates to an improvement of a microwave reflector installed on a mountaintop or the like where a pair of microwave transmitting / receiving stations or relay stations, which are communication partners with each other, cannot be seen from each other topographically.

[Conventional technology]

In order to propagate microwaves between a microwave transceiver station and a microwave relay station that are not in topographical mutual visibility, there is a technology to install a large metal reflector on the peak or hillside where mutual visibility is possible. Are known. This reflector is, for example, a metal flat plate having a length of 10 meters and a height of 8 meters, and its surface is a perfect plane of a metal conductor.
As illustrated in FIG. 4, this reflector is installed by a steel support structure.

As shown in FIG. 7, it is known that this perfect flat reflector has a null point in its reflection characteristic. That is, FIG. 7A shows the vertical reflection characteristic, and FIG. 7B shows the horizontal reflection characteristic. About 0 in either direction.
There is a null point at which the reflection characteristic sharply becomes zero at a slightly shifted angle of 2 degrees. This is because even if the reflector itself is formed in a considerably large size, there is a portion in which the phases of the radio waves reflected at the two ends of the reflector are just cancelled.

As described above, when the angle changes slightly, the reflection characteristics sharply decrease, so the reflection characteristics deteriorate when there is a slight change in the reflection plate installed on the summit or hillside due to the influence of wind and other weather. To do.

[Problems to be solved by the invention]

Conventionally, in order to avoid this, the technique disclosed in Japanese Utility Model Laid-Open No. 55-39751 is known. In this, as shown in FIG. 8, the reflecting surface of the reflecting plate is formed into a slightly curved surface instead of a perfect flat surface so that a sharp null point does not occur due to a small angle shift. This technology is an excellent technology, but if this is done on a large metal plane as described above, the height difference from the perfect plane will be about 5 mm at a position several meters away from the center point of the reflector. It is not impossible to perform such curved surface processing on a metal flat surface, but there is a drawback that the cost required for the processing is not practical.

The present invention improves on this, and an object of the present invention is to provide a microwave reflector capable of substantially eliminating the null point of the reflection characteristic with a smaller processing man-hour as compared with the above-mentioned conventional technique.

[Means for solving problems]

According to the present invention, a reflection surface is a conductor arranged in a passage of a microwave propagating in a space, and the reflection surface is a microwave reflection formed by attaching a large number of conductor plates horizontally and vertically to a single substrate. In the plate, the conductor plate is a plurality of kinds of conductor flat plates each having a rectangular shape (including a square shape) having a side of 1 to several meters and a thickness of several millimeters or less. It is characterized in that the central portion is formed in a stepwise shape in the horizontal and / or the vertical direction so as to be a concave surface which is recessed from the four corners by one to several steps of the conductor plate.

[Action]

The reflector of the present invention can be realized by cutting a perfect flat reflector in a stepwise manner or by attaching a rectangular segment having a thickness of 1 mm to several mm to the perfect flat reflector. This is far smaller in processing man-hours than performing curved surface processing on a metal flat surface as described above. Moreover, as a result of the test, its reflection characteristic does not become an ideal value,
It was confirmed that there was practically no null point and the characteristics were sufficiently practical.

〔Example〕

 Next, an embodiment of the present invention will be described with reference to the drawings.

FIG. 1 is a schematic perspective view showing the appearance of the first embodiment of the present invention. This figure shows the case of a microwave reflector with a length of 10 m in the horizontal direction and a length of 8 m in the vertical direction. Doubled).

In the figure, the reflection surface of the base 11 of the reflection plate is formed of a conductor into a substantially flat shape.

A feature of the present invention is that stepped portions 2 and 3 are formed on the reflecting surface, which are slightly displaced with respect to the perfect plane 1 installed on the base 11.

That is, the base 11 is made of a steel plate, and the central portion of the base 11 is slightly cut out in the longitudinal direction so as to form a perfect plane 1 by fitting a thin metal plate 12. In this embodiment, the length is 8
A thin metal plate 12 having a width of 4 m and a width of 1 m is attached to the base 11 to form a perfect plane 1.

Next, with respect to the perfect plane 1, a vertical step portion 2 and a lateral step portion 3 are formed, respectively, and rectangular metal segments 13, 14, 15, which have planes parallel to the perfect plane 1, respectively. 16 is attached to the base 11.

FIG. 2 shows a schematic sectional view of the first embodiment. Also in this figure, the dimension of the reflection plate in the thickness direction is greatly enlarged.

2 (a) and 2 (b) show the X- line shown in FIG.
It is a cross-sectional schematic diagram of X'view and YY 'view.

In FIG. 2 (a), the thickness of the segment 13 is 5 mm based on the perfect plane 1 of the metal thin plate 12, and the segment 1
The thicknesses of 4, 15, and 16 are 2 mm, 1 mm, and 0.5 mm, respectively. The dimensions of these segments are 3 m in the horizontal direction and 1 m in the vertical direction according to FIGS. 2 (a) and 2 (b), and the required number of each is four.

In this way, by mounting eight thin metal plates 12 and four segments 13 to 16 on the base 11, the reflector of the embodiment shown in FIG. 1 can be formed.

FIG. 3 shows the calculation result of the radiation directivity characteristic of the first embodiment. FIG. 3 (a) shows the vertical characteristics, and FIG. 3 (b).
Indicates a lateral characteristic. In either case, the null point occurring at ± 0.2 degrees with respect to the central axis almost disappears.

Therefore, as shown in FIG. 4, a metal reflector 24 for performing microwave propagation between the microwave transceiver station 22 and the microwave relay station 23 whose direct view is blocked by the mountain 21.
Even if there is a slight fluctuation due to the influence of wind and other weather, the reflection characteristics do not deteriorate rapidly.

FIG. 5 is a schematic perspective view showing the outer appearance of the second embodiment of the present invention, and FIG. 6 is a schematic sectional view of the second embodiment. Also in these figures, the dimension of the reflection plate in the thickness direction is remarkably enlarged as in FIGS. 1 and 2.

In the second embodiment, the number of stepped portions provided on the reflecting surface is larger than that of the first embodiment to complicate the shape of the reflecting surface, and each reflecting surface has a unit of size 1 m × 1 m. It is a combination of planes.

As shown in FIG. 5 and FIG. 6, the metal thin plates 31 forming the perfect plane 1 are 16 bases each having a size of 1 m × 1 m.
It fits into the 31 notches.

Segment 36 (thickness 0.5 mm), segment 35 (thickness 1 mm), and segment 34 (thickness 2 mm) on the left and right sides of the horizontal direction are 4 in the vertical direction.
You can attach them horizontally one by one. Furthermore, three segments 33 (thickness: 5 mm) and one segment 37 (thickness: 2 mm) are horizontally attached to each corner, and are stuck together, the central part is recessed, and each corner is slightly protruding. Is formed.

In the above-mentioned two embodiments, the base is described as one plate having a notch, but this is a thin metal plate forming a complete flat surface and each step can obtain a stepped portion required. It can be of a frame structure of construction.

[Effect of device]

According to the present invention, there is an effect that a microwave reflecting plate whose reflection characteristics are less likely to be deteriorated even if the reflecting plate is slightly changed can be realized with a small number of manufacturing steps and installation steps.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic perspective view showing the appearance of a first embodiment of the present invention. FIG. 2 is a schematic sectional view of the above embodiment. FIG. 2A is a view taken along line XX ′ shown in FIG. FIG. 2B is a view taken along the line YY ′ shown in FIG. FIG. 3 is a radiation indicating characteristic diagram of the above embodiment. FIG. 3A is a vertical characteristic diagram. FIG. 3B is a lateral characteristic diagram. FIG. 4 is an explanatory view of an embodiment of this embodiment. FIG. 5 is a schematic perspective view showing the appearance of the second embodiment of the present invention. FIG. 6 is a schematic sectional view of the above embodiment. FIG. 6 (a) is a view taken along line XX 'shown in FIG. FIG. 6 (b) is a view taken along the line YY 'shown in FIG. FIG. 7 is a radiation indicating characteristic diagram of a conventional flat reflector. FIG. 7A is a vertical characteristic diagram. FIG. 7B is a lateral characteristic diagram. FIG. 8 is a shape diagram of a conventional example in which the reflecting surface is a curved surface. 1 ... Perfect plane, 2 ... Vertical step-like portion, 3 ... Horizontal step-like portion, 11, 31 ... Base, 12, 32 ... Metal sheet that forms a complete plane, 13, 14 , 15, 16, 33, 34, 35,
36, 37 …… Segment, 21 …… Mountain, 22 …… Microwave transceiver station, 23 …… Micro relay station, 24 …… Metal reflector.

Claims (1)

[Scope of utility model registration request] 1. A microwave which is arranged in a passage of a microwave propagating in a space, a reflecting surface of which is a conductor, and which is formed by sticking a large number of conductor plates horizontally and vertically on a single substrate. In the reflector, the conductor plate is a plurality of types of conductor flat plates each having a side of 1 to several meters and a thickness of several millimeters or less, and the center of the reflection surface has four corners. A microwave reflecting plate, characterized in that it is formed in a step shape in a horizontal or vertical direction so as to form a concave surface which is recessed by one to several steps of the conductor plate.