JPH06177640A - Circularity/linearity polarized wave converter - Google Patents

Abstract

PURPOSE:To provide the circularly/linearly polarized wave converter whose performance deterioration is small when the converter is made composite to a plane antenna. CONSTITUTION:Three sheets 1 on which nearly the same pattern of meander lines 10 are sequentially laminated while a very thin insulation sheet 3 made of a foamed plastic is inserted among them. A sheet 2 on which a pattern of other meander lines 20 different from the lines 10 on the sheet 1 is formed is laminated to the lowermost part of the laminated layers.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a circular / linear polarization converter to be combined with a plane antenna used for reception of broadcasting satellites requiring a polarization conversion function or mobile communication.

[0002]

2. Description of the Related Art A circular / linear polarization converter using a so-called meander line that performs polarization conversion by creating an orthogonal vector with a phase difference of 90 degrees has high-performance polarization conversion performance. (L.Young, LARobinson, and C.
A.Hacking, "Meander-Line polarizer", IEEE, Trans.Ante
nna Propagat., vol.AP-21, pp.376-378, May 1973),
(Miyahara, Makino: "Meander line loading patch antenna", Sho 61 General Conference, 647).

[0003]

The circular / linear polarization converter using the meander line as described above often has a good axial ratio characteristic, but it has a multi-layer structure, especially for a planar antenna or the like. When combined, the gain may be lowered due to mutual coupling with the antenna element or deterioration of the reflection characteristic.

Therefore, it has become necessary to design a circular / linear polarization converter with a small gain reduction, especially when designing a planar antenna used for reception of broadcasting satellites. The present invention has been made in view of the above points, and an object of the present invention is to provide a circular-polarization converter having a small performance deterioration when combined with a planar antenna. .

In addition to the above object, an object of the present invention is to provide a circular / linear polarization converter which can be easily manufactured and is low in cost.

[0006]

In order to achieve the above object, the invention according to claim 1 is to be combined with a linearly polarized plane antenna, wherein a meander line pattern having a polarization conversion function is provided. In a circular / linear polarization polarizer configured by laminating the formed layers, three layers having the same meander line pattern and one layer having another meander line pattern are formed. And is laminated.

According to a second aspect of the invention, in the first aspect of the invention, a sheet-like material having a foam material or a space portion and an ultrathin sheet having a meander line are laminated.

[0008]

According to the first aspect of the invention, the conversion function can be enhanced by suppressing the mutual coupling and reflection between the patterns of the meander line, and the performance deterioration particularly when combined with the planar antenna. A small circular / linear polarization converter can be realized. According to the invention of claim 2, the ultra-thin sheet having the meandering line pattern formed thereon can be easily manufactured by simply laminating the foamed sheet, so that there is no need to use a special manufacturing method and the cost is reduced. Will also be cheaper.

As a result, an extremely high performance circularly polarized plane antenna can be realized at low cost by combining it with a plane antenna that generates linearly polarized waves.

[0010]

EXAMPLES The present invention will be described below with reference to examples. FIG. 1 shows an exploded perspective view of one embodiment. In the illustrated embodiment, three sheets 1 forming substantially the same meander line pattern 10 and another meander line pattern 20 are formed. The sheet 2 is formed by laminating one sheet 2 and three extremely thin insulating sheets 3 made of foamed plastic as shown in the figure.

The sheet 1 is a commercially available 50 μm thick polyester-based flexible printed board on which a pattern of the meander line 10 is formed by etching. The formed meander line 10 pattern has a height of 4 mm and a pitch. A meander line of 4 mm and a line width of 0.4 mm is arranged at intervals of 11 mm. The sheet 2 is made of the same flexible printed circuit board as the sheet 1, and the pattern of the meander line 20 formed by etching is 3.5 mm in height and 2 m in pitch.
m, line width 0.5mm meander line 11.2mm
The patterns are arranged at intervals of, which is different from the pattern of the sheet 1.

The insulating sheet 3 is a foam plastic sheet having a thickness of 5 mm. Then, as shown in FIG. 2, the three sheets 1 are sequentially laminated with the insulating sheet 3 interposed therebetween, and the sheet 2 is arranged at the lowermost portion to obtain the circular / linear polarization converter of this embodiment. It will be different. Here, the circular / linear polarization converter of the present embodiment was combined with a linearly polarized plane antenna to create a circularly polarized antenna, and its performance was evaluated. As a result, a band of 12 to 13 GHz was obtained. It was confirmed that the cross polarization characteristic of 25 dB or more was achieved and the gain loss was suppressed to 0.2 dB or less.

The condition of the above embodiment is an example obtained by repeating the theoretical calculation of the reflection condition, mutual coupling, etc. and the confirmation of the experiment.
In the above-described embodiment, three sheets 1 on which the pattern of the substantially meander line 10 is formed are sequentially laminated with the insulating sheet 3 interposed therebetween, and the sheet 2 on which another pattern of the meander run 20 is formed at the lowermost portion. Was arranged, but as shown in FIG. 3A, the seat 2 is arranged at the top,
As shown in FIGS. 3 (b) and 3 (c), the same performance as that of the embodiment of FIG.
The present invention is not particularly limited to the stacking order of the embodiment of FIG.

[0014]

According to the first aspect of the present invention, three layers having the same meander line pattern are laminated and one layer having another meander line pattern is laminated. The conversion function can be improved by suppressing the reflection between the patterns of the meander line and the meander line, and in particular, a circular / linear polarization converter with little performance degradation when combined with a planar antenna can be realized, resulting in a wide range of applications such as satellite broadcasting There is an effect that it is possible to realize an extremely high-performance planar antenna applicable to.

According to a second aspect of the present invention, in the first aspect of the present invention, a sheet-like material having a foam material or a space portion and an ultrathin sheet having a meander line are laminated. It can be easily manufactured by simply laminating the ultra-thin sheet on which the pattern of the line is formed through the foamed sheet, so there is no need to use a special manufacturing method,
Further, there is an effect that the cost becomes low.

[Brief description of drawings]

FIG. 1 is an exploded perspective view of an embodiment of the present invention.

FIG. 2 is a sectional view of the same.

FIG. 3A is a sectional view of another embodiment of the present invention.
(B) is sectional drawing of other Example of this invention. (C) is sectional drawing of other Examples of this invention.

[Explanation of symbols]

 1 sheet 2 sheet 3 insulating sheet 10 meander line 20 meander line

Claims (2)

[Claims] 1. A circular / linearly polarized wave polarizer which is combined with a linearly polarized plane antenna and is formed by laminating multiple layers having a meandering line pattern having a polarization conversion function. A circular / linear polarization converter comprising: three layers having the same meander line pattern formed thereon and one layer having another meander line pattern formed thereon. 2. The circular / linear polarized wave according to claim 1, wherein a foamed material or a sheet-shaped material having a space portion and an ultrathin sheet having a meander line are sequentially laminated. converter.