JPH03191604A - Antenna equipment - Google Patents
Antenna equipmentInfo
- Publication number
- JPH03191604A JPH03191604A JP33222189A JP33222189A JPH03191604A JP H03191604 A JPH03191604 A JP H03191604A JP 33222189 A JP33222189 A JP 33222189A JP 33222189 A JP33222189 A JP 33222189A JP H03191604 A JPH03191604 A JP H03191604A
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- mirror
- reflecting mirror
- sub
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- 230000005855 radiation Effects 0.000 abstract description 8
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- 230000007423 decrease Effects 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 1
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Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
この発明は、アンテナ装置に関し、特に回線の信鯨性を
向上する等のために２つの衛星に同時にアクセスする衛
星通信地球局に用いられるものに関するものである。[Detailed Description of the Invention] [Industrial Application Field] This invention relates to an antenna device, and in particular to an antenna device used in a satellite communication earth station that accesses two satellites simultaneously in order to improve the reliability of the line. It is related to.
第４図は、例えば昭和６３年に発行された“電子情報通
信学会アンテナ・伝播研究会研究会資料（Ａ−Ｐ８８−
１５１）”に示された従来のアンテナ装置を示す概略構
成図であり、図において、１は主反射鏡、２は副反射鏡
、３ａ、３ｂは２つの衛星に対応してそれぞれ設けられ
た給電部、４ａ、４ｂは複数枚の反射鏡から上記給電部
を構成する集束ビーム給電系、５は上記給電部を構成す
る一次放射器、６は２つの衛星の方向である。ここで、
主反射鏡ｌ及び副反射鏡２はそれぞれ放物線及び楕円を
軸り、の回りに回転して得られるトーラス鏡面である。Figure 4 shows, for example, "IEICE Antenna and Propagation Study Group Materials (A-P88-
151)" is a schematic configuration diagram showing the conventional antenna device shown in "151)", in which 1 is a main reflector, 2 is a sub-reflector, and 3a and 3b are power feeders provided corresponding to two satellites, respectively. 4a and 4b are a focused beam feeding system comprising a plurality of reflecting mirrors, 5 is a primary radiator forming the feeding section, and 6 is the direction of the two satellites.Here,
The main reflecting mirror 1 and the sub-reflecting mirror 2 are torus mirror surfaces obtained by rotating around a parabola and an ellipse, respectively.
また、第５図は、例えば“昭和５７年度電子通信学会総
合全国大会（講演番号６８７）予稿集”に示された従来
のアンテナ装置を示す概略構成図であり、図において、
１は主反射鏡、２ａ、２ｂは副反射鏡、３ａ、３ｂは２
つの衛星それぞれに対応して設けられた給電部、４ａ、
４ｂは複数枚の反射鏡から上記給電部を構成する集束ビ
ーム給電系、５ａ、５ｂは上記給電部を構成する一次放
射器、６ａ、５ｂは２つの衛星の方向である。なお、主
反射鏡１は点ＰＣを曲率中心とする球面鏡である。Further, FIG. 5 is a schematic configuration diagram showing a conventional antenna device shown in, for example, the 1981 National Institute of Electronics and Communication Engineers General Conference (Lecture No. 687) Proceedings, and in the figure,
1 is the main reflecting mirror, 2a and 2b are the sub-reflecting mirrors, 3a and 3b are 2
A power feeding unit provided corresponding to each of the two satellites, 4a,
Reference numeral 4b indicates a focused beam feeding system that constitutes the above-mentioned power feeding section from a plurality of reflecting mirrors, 5a and 5b indicate primary radiators that constitute the above-mentioned feeding section, and 6a and 5b indicate the directions of the two satellites. Note that the main reflecting mirror 1 is a spherical mirror whose center of curvature is the point PC.
次に動作について説明する。第４図において、給電部３
ａに設けられた一次放射器５ａから放射された電波は、
集束ビーム給電系４ａ、副反射鏡２、主反射鏡１で反射
された後、一方の衛星方向６ａに放射される。同様に、
給電部３ｂに設けられた一次放射器５ｂから放射された
電波は、集束ビーム給電系４ｂ、副反射鏡２．主反射鏡
１で反射された後、一方の衛星方向６ｂに放射される。Next, the operation will be explained. In Fig. 4, the power supply section 3
The radio waves radiated from the primary radiator 5a provided at
After being reflected by the focused beam feeding system 4a, the sub-reflector 2, and the main reflector 1, it is radiated toward one of the satellites 6a. Similarly,
Radio waves radiated from the primary radiator 5b provided in the power feeding section 3b are transmitted to a focused beam feeding system 4b, a sub-reflector 2. After being reflected by the main reflecting mirror 1, it is radiated toward one satellite direction 6b.
従って、このアンテナ装置を用いると、６ａ、６ｂの２
つの衛星方向に独立に電波を放射するために、２つの衛
星に同時にアクセスできる。Therefore, if this antenna device is used, two of 6a and 6b
Two satellites can be accessed simultaneously in order to radiate radio waves independently in the directions of two satellites.
また、第５図において、給電部３ａに設けられた一次放
射器５ａから放射された電波は、集束ビーム給電系４ａ
、副反射鏡２ａ、主反射鏡１で反射された後、一方の衛
星方向６ａに放射される。In addition, in FIG. 5, the radio waves radiated from the primary radiator 5a provided in the power feeding section 3a are transmitted to the focused beam feeding system 4a.
, the sub-reflector 2a, and the main reflector 1, and then radiated in one direction toward the satellite 6a.
同様に、給電部３ｂに設けられた一次放射器５ｂから放
射された電波は、集束ビーム給電系４ｂ。Similarly, the radio waves radiated from the primary radiator 5b provided in the power supply section 3b are transmitted to the focused beam power supply system 4b.
副反射鏡２ｂ、主反射鏡１で反射された後、もう一方の
衛星方向６ｂに放射される。従って、このアンテナ装置
を用いると、６ａ、６ｂの２つの衛星方向に独立に電波
を放射するために、２つの衛星を同時にアクセスできる
。After being reflected by the sub-reflector 2b and the main reflector 1, it is radiated in the other satellite direction 6b. Therefore, by using this antenna device, two satellites can be accessed simultaneously in order to independently radiate radio waves in the directions of the two satellites 6a and 6b.
第３図は２つの衛星方向６ａ、６ｂを説明する図である
０図において、ξ軸、η軸はそれぞれＡｚｉｍｕｔｈ方
向、Ｅｌｅｖａｔｉｏｎ方向の角度を表わす座標系、ξ
。、η。はそれぞれ２つの衛星の中心の方向を表わすξ
、η座標系であり、６ａ、６ｂは２つの衛星の方向、７
は静止衛星に対する追尾範囲を表わす、８は衛星のドリ
フトによる軌跡であり、９ａ、９ｂはアンテナ装置の衛
星に対する追尾範囲を表す、１０は２つの衛星の追尾範
囲９ａ、９ｂを含む追尾範囲を表わす、またαはη軸と
衛星軌道面７とのなす角度、θ１は２つの衛星方向６ａ
と６ｂとの分離角度、θ９はそれぞれ２つの衛星のドリ
フト角度である。FIG. 3 is a diagram illustrating two satellite directions 6a and 6b. In FIG.
. ,η. ξ represents the direction of the center of the two satellites, respectively
, η coordinate system, 6a, 6b are the directions of the two satellites, 7
represents the tracking range for the geostationary satellite, 8 is the trajectory due to the drift of the satellite, 9a and 9b represent the tracking range for the satellite of the antenna device, and 10 represents the tracking range including the tracking ranges 9a and 9b for the two satellites. , α is the angle between the η axis and the satellite orbital plane 7, and θ1 is the direction of the two satellites 6a.
and 6b, and θ9 are the drift angles of the two satellites, respectively.
従来のアンテナ装置は以上のように構成されているので
、第４図の従来例では、衛星のドリフト角度θ１が大き
い場合には収差を生じ、アンテナの利得が低下したり、
サイドローブレベルが上昇するなどの問題があった。Since the conventional antenna device is configured as described above, in the conventional example shown in FIG. 4, when the drift angle θ1 of the satellite is large, aberrations occur and the antenna gain decreases.
There were problems such as an increase in the sidelobe level.
また、第５図の従来例では、第４図の従来例のような問
題点はないが、２つの衛星の追尾範囲９ａ、９ｂを含む
追尾範囲１０に対応して主反射鏡１の利用範囲が変わる
ので、主反射鏡１の寸法が大きくなるという問題があっ
た。Furthermore, although the conventional example shown in FIG. 5 does not have the same problems as the conventional example shown in FIG. Since the angle changes, there is a problem that the dimensions of the main reflecting mirror 1 become large.
この発明は、上記のような問題点を解消するためになさ
れたもので、位置変動の大きい衛星を追尾するアンテナ
装置において、主反射鏡１の寸法を小さくでき、収差に
よるアンテナの利得低下やサイドロープレベルの上昇な
どの放射特性の劣化のないアンテナ装置を得ることを目
的とする。This invention was made to solve the above-mentioned problems, and in an antenna device that tracks a satellite with large positional fluctuations, it is possible to reduce the size of the main reflector 1, and it is possible to reduce the antenna gain due to aberration and side It is an object of the present invention to obtain an antenna device that does not cause deterioration of radiation characteristics such as an increase in rope level.
この発明に係るアンテナ装置は、主反射鏡、副反射鏡及
び２組の給電部から構成し、上記主反射鏡及び上記副反
射鏡はそれぞれ同一面内にある鏡面曲線をある回転軸の
回りに回転して得られる曲面からなり、上記鏡面曲線は
２つの異なる方向から入射した平面波が上記主反射鏡及
び副反射鏡上の鏡面曲線により順次反射されて、それぞ
れ異なる２つの焦点Ｆ１及びＦ２に集束させるように、
各々の鏡面の位置及び法線方向を設定し、上記２組の給
電部を上記回転軸の回りに回転させる機構を設けたもの
である。The antenna device according to the present invention is composed of a main reflecting mirror, a sub-reflecting mirror, and two sets of power feeding parts, and the main reflecting mirror and the sub-reflecting mirror rotate mirror curves in the same plane around a certain rotation axis. It consists of a curved surface obtained by rotation, and the mirror curve is such that plane waves incident from two different directions are sequentially reflected by the mirror curves on the main reflecting mirror and the sub-reflecting mirror, and are focused on two different focal points F1 and F2, respectively. as if to let
A mechanism is provided that sets the position and normal direction of each mirror surface and rotates the two sets of power feeding units about the rotation axis.
この発明におけるアンテナ装置は、上記主反射鏡及び上
記副反射鏡をそれぞれ同一面内にある鏡面白線をある回
転軸の回りに回転して得られる曲面から構成し、上記鏡
面曲線を２つの異なる方向から入射した平面波が上記主
反射鏡及び副反射鏡上の鏡面曲線により順次反射されて
、それぞれ異なる２つの焦点Ｆ、及びＦ８に集束させる
ように各々の鏡面の位置及び法線方向を設定し、上記２
組の給電部を上記回転軸の回りに回転する機構を設ける
ようにしたので、衛星を追尾するときに生じる収差がな
くなり、収差によるアンテナの利得低下やサイドローブ
レベルの上昇などの放射特性の劣化のないアンテナ装置
を得ることができる。In the antenna device of the present invention, each of the main reflecting mirror and the sub-reflecting mirror is configured with a curved surface obtained by rotating mirror plane lines in the same plane around a certain rotation axis, and the mirror plane curve is rotated in two different directions. The position and normal direction of each mirror surface are set so that the plane wave incident on the main reflecting mirror and the sub-reflecting mirror are sequentially reflected by the mirror curves on the main reflecting mirror and the sub-reflecting mirror and focused on two different focal points F and F8, respectively, Above 2
Since a mechanism is provided to rotate the power supply section of the set around the rotation axis, aberrations that occur when tracking a satellite are eliminated, and deterioration of radiation characteristics such as a decrease in antenna gain and an increase in sidelobe levels due to aberrations is avoided. It is possible to obtain an antenna device without.
以下、この発明の一実施例を図について説明する。 An embodiment of the present invention will be described below with reference to the drawings.
第１図は本発明の一実施例によるアンテナ装置を示し、
図において、１は主反射鏡、２は副反射鏡、３ａ、３ｂ
は給電部、４．５はそれぞれ給電部を構成する反射鏡と
一次放射器、６は衛星の方向を表わしている。４ａは衛
星の方向６ａから入射した平面波が主反射＠１．副反射
鏡２により順次反射され、−次放射器５ａに集束するよ
うに構成された反射鏡である。４ｂは衛星の方向６ｂか
ら入射した平面波が主反射鏡ｌ、副反射鏡２により順次
反射され、−次放射器５ｂに集束するように構成された
反射鏡である。FIG. 1 shows an antenna device according to an embodiment of the present invention,
In the figure, 1 is the main reflecting mirror, 2 is the sub-reflecting mirror, 3a, 3b
4.5 represents a reflecting mirror and a primary radiator which constitute the power feeding section, and 6 represents the direction of the satellite. 4a, the plane wave incident from the direction 6a of the satellite is the main reflection @1. This is a reflecting mirror configured to be sequentially reflected by the sub-reflecting mirror 2 and focused on the -order radiator 5a. Reference numeral 4b denotes a reflecting mirror configured such that a plane wave incident from the direction 6b of the satellite is sequentially reflected by the main reflecting mirror 1 and the sub-reflecting mirror 2, and focused on the -order radiator 5b.
第１図において、−次放射器５ａから放射された電波は
反射鏡４ａで反射された後、副反射鏡２゜主反射鏡１に
より順次反射され、一方の衛星方向６ａに波面収差のな
い状態で放射される。同様に、−次放射器５ｂから放射
された電波は反射鏡４ｂで反射された後、副反射鏡２．
主反射ａｌｌにより順次反射され、もう一方の衛星方向
６ｂに波面収差のない状態で放射される。主反射鏡１及
び副反射鏡２はそれぞれ同一面内にある鏡面曲線Ｍ −
ｒ Ｍ ｔＭ、及びＳ−＋Ｓ＋ Ｓ−ｔを直線りの回り
に回転して得られる曲面から構成され、給電部３ａ及び
３ｂはそれぞれ独立に直線りの回りに回転するので、ア
ンテナの放射ビームの方向は直線りを通り、かつ直線り
の回りに回転する。即ち、給電部３が直線りの回りに回
転したとき、アンテナの放射ビームの方向は波面収差の
ない状態でコニカル状に変化する。一方、衛星の位置は
地球の中心から一定の距離を保ちながら南北方向に変動
するので、地上から見える衛星の位置変動の軌跡はわず
かながら円弧状になる。従って、衛星を追尾するには、
上記コニカル状に放射ビーム方向が変化するアンテナ装
置が有利である。In FIG. 1, the radio waves emitted from the -order radiator 5a are reflected by the reflector 4a, and then sequentially reflected by the sub-reflector 2 and the main reflector 1, so that there is no wavefront aberration in one satellite direction 6a. radiated by. Similarly, the radio waves emitted from the -order radiator 5b are reflected by the reflecting mirror 4b, and then reflected by the sub-reflecting mirror 2.
The light is sequentially reflected by the main reflection all and radiated in the direction of the other satellite 6b without wavefront aberration. The main reflecting mirror 1 and the sub-reflecting mirror 2 each have a mirror curve M − in the same plane.
It is composed of a curved surface obtained by rotating r M tM and S-+S+ S-t around a straight line, and since the feeding parts 3a and 3b each rotate around a straight line independently, the radiation beam of the antenna The direction is a straight line and rotation around the straight line. That is, when the feeding section 3 rotates around a straight line, the direction of the radiation beam of the antenna changes conically without wavefront aberration. On the other hand, since the satellite's position changes in the north-south direction while maintaining a constant distance from the center of the earth, the trajectory of the satellite's position change as seen from the ground forms a slight arc. Therefore, to track a satellite,
An antenna arrangement in which the radiation beam direction changes conically is advantageous.
第２図は給電部３の回転移動に伴う主反射鏡１の利用範
囲の変化の比較を示す図である。第２図（ａ）は第３図
に示したように主反射鏡１が球面鏡の場合を示す、第２
図（ロ）は第１図に示したこの発明の実施例の場合を示
す、この発明の実施例によれば、給電部３の直線りの回
りの回転移動に伴う主反射鏡ｌの利用範囲は一次元的に
変化する。一方、第３図のように主反射鏡１が球面鏡の
場合は給電部３の点ＰＣの回りの回転移動に伴う主反射
＠１の利用範囲は、二次元的に変化する。従って、この
実施例によれば主反射鏡ｌの利用範囲の小さいアンテナ
装置が得られるので、例えば従来４ＧＨｚ帯で直径２０
ｍの主反射鏡ｌを必要としたものが、第２図（ａ）、
（ｂ）から分かるように約半分に小型化でき、小型の地
球局アンテナが得られることになる。FIG. 2 is a diagram showing a comparison of changes in the usage range of the main reflecting mirror 1 due to the rotational movement of the power feeding section 3. In FIG. FIG. 2(a) shows the case where the main reflecting mirror 1 is a spherical mirror as shown in FIG.
Figure (B) shows the case of the embodiment of the present invention shown in FIG. changes in one dimension. On the other hand, when the main reflecting mirror 1 is a spherical mirror as shown in FIG. 3, the usage range of the main reflection @1 changes two-dimensionally as the power feeding section 3 rotates around the point PC. Therefore, according to this embodiment, it is possible to obtain an antenna device in which the usable range of the main reflector l is small.
Figure 2(a) shows the one that requires main reflector l of m.
As can be seen from (b), the size can be reduced to about half, resulting in a compact earth station antenna.
以上のように、この発明に係るアンテナ装置によれば、
主反射鏡、副反射鏡及び２組の給電部から構成され、上
記主反射鏡及び上記副反射鏡はそれぞれ同一面内にある
鏡面曲線をある回転軸の回りに回転して得られる曲面か
らなり、上記鏡面曲線は２つの異なる方向から入射した
平面波が上記主反射鏡及び副反射鏡上の鏡面曲線により
順次反射されて、それぞれ異なる２つの焦点Ｆｌ及びＦ
。As described above, according to the antenna device according to the present invention,
It consists of a main reflecting mirror, a sub-reflecting mirror, and two sets of power supply parts, and each of the main reflecting mirror and the sub-reflecting mirror consists of a curved surface obtained by rotating a mirror curved line in the same plane around a certain rotation axis. , the mirror curve is formed by plane waves incident from two different directions being sequentially reflected by the mirror curves on the main reflecting mirror and the sub reflecting mirror, resulting in two different focal points Fl and F, respectively.
.
に集束し、上記２組の給電部を上記回転軸の回りに回転
させる機構を設けたので、上記主反射鏡の寸法が小さ（
、また大きく位置変動する２つの衛星を同時かつ独立に
追尾する場合に収差が発生せず、利得低下やサイドロー
ブレベルの上昇などの性能劣化のないアンテナ装置が得
られる効果がある。Since a mechanism is provided to rotate the two sets of power feeding parts around the rotation axis, the size of the main reflecting mirror is small (
Furthermore, when simultaneously and independently tracking two satellites whose positions fluctuate greatly, no aberrations occur, and an antenna device without performance deterioration such as a decrease in gain or an increase in sidelobe level can be obtained.
第１図はこの発明の一実施例によるアンテナ装置を示す
概略構成図、第２図は主反射鏡の利用領域の比較を説明
するための図、第３図は２つの衛星の方向を説明する図
、第４図及び第５図は従来のこの種のアンテナ装置を示
す概略構成図である。
図において、１は主反射鏡、２は副反射鏡、３は２つの
衛星それぞれに対応して設けた給電部、４は複数枚の反
射鏡から上記給電部を構成する集束ビーム給電系、５は
上記給電部を構成する一次放射器、６は２つの衛星の方
向、７は静止衛星軌道面、８は衛星の位置変動軌跡、９
．１０は衛星の追尾範囲である。
なお図中同一符号は同−又は相当部分を示す。FIG. 1 is a schematic configuration diagram showing an antenna device according to an embodiment of the present invention, FIG. 2 is a diagram for explaining a comparison of the usage areas of the main reflector, and FIG. 3 is a diagram for explaining the directions of two satellites. 4 and 5 are schematic configuration diagrams showing a conventional antenna device of this type. In the figure, 1 is a main reflecting mirror, 2 is a sub-reflecting mirror, 3 is a power feeding section provided corresponding to each of the two satellites, 4 is a focused beam feeding system that constitutes the above feeding section from a plurality of reflecting mirrors, and 5 is the primary radiator constituting the above-mentioned power feeding section, 6 is the direction of the two satellites, 7 is the geostationary satellite orbit plane, 8 is the position fluctuation trajectory of the satellite, 9
．． 10 is the tracking range of the satellite. Note that the same reference numerals in the figures indicate the same or equivalent parts.
Claims (3)
され、２つの衛星に同時かつ独立にアクセスできるアン
テナ装置において、 上記主反射鏡及び上記副反射鏡は、それぞれ同一面内に
ある鏡面曲線をある回転軸の回りに回転して得られる曲
面からなり、 かつ、２つの異なる方向から入射した平面波が上記主反
射鏡及び副反射鏡上の上記鏡面曲線により順次反射され
て、それぞれ異なる２つの焦点に集束するように上記主
反射鏡及び副反射鏡の鏡面曲線を定めたことを特徴とす
るアンテナ装置。(1) In an antenna device that is composed of a main reflector, a sub-reflector, and two sets of power feeding parts and can access two satellites simultaneously and independently, the main reflector and the sub-reflector are each in the same plane. It consists of a curved surface obtained by rotating a mirror curve located in An antenna device characterized in that mirror curves of the main reflecting mirror and the sub-reflecting mirror are determined so as to focus on two different focal points.
束ビーム給電系から構成され、ある回転軸の回りに回転
する機構を上記各給電部に設けたことを特徴とする請求
項１記載のアンテナ装置。(2) A claim characterized in that each power feeding section is constituted by a focused beam feeding system consisting of a primary radiator and one reflecting mirror, and each of the power feeding sections is provided with a mechanism that rotates around a certain rotation axis. 1. The antenna device according to 1.
る集束ビーム給電系から構成され、ある回転軸の回りに
回転する機構を一部の反射鏡に設けたことを特徴とする
請求項１記載のアンテナ装置。(3) Each feeding section is composed of a focused beam feeding system consisting of a primary radiator and one or more reflecting mirrors, and some of the reflecting mirrors are provided with a mechanism to rotate around a certain rotation axis. The antenna device according to claim 1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1332221A JPH07118609B2 (en) | 1989-12-20 | 1989-12-20 | Antenna device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP1332221A JPH07118609B2 (en) | 1989-12-20 | 1989-12-20 | Antenna device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03191604A true JPH03191604A (en) | 1991-08-21 |
| JPH07118609B2 JPH07118609B2 (en) | 1995-12-18 |
Family
ID=18252528
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP1332221A Expired - Fee Related JPH07118609B2 (en) | 1989-12-20 | 1989-12-20 | Antenna device |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH07118609B2 (en) |
Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6048603A (en) * | 1983-08-29 | 1985-03-16 | Nippon Telegr & Teleph Corp <Ntt> | Antenna system |
-
1989
- 1989-12-20 JP JP1332221A patent/JPH07118609B2/en not_active Expired - Fee Related
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6048603A (en) * | 1983-08-29 | 1985-03-16 | Nippon Telegr & Teleph Corp <Ntt> | Antenna system |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH07118609B2 (en) | 1995-12-18 |
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