JPS6048603A - Antenna system - Google Patents
Antenna systemInfo
- Publication number
- JPS6048603A JPS6048603A JP15631583A JP15631583A JPS6048603A JP S6048603 A JPS6048603 A JP S6048603A JP 15631583 A JP15631583 A JP 15631583A JP 15631583 A JP15631583 A JP 15631583A JP S6048603 A JPS6048603 A JP S6048603A
- Authority
- JP
- Japan
- Prior art keywords
- sub
- reflecting mirror
- mirror
- reflector
- main
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Granted
Links
Classifications
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01Q—ANTENNAS, i.e. RADIO AERIALS
- H01Q19/00—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic
- H01Q19/10—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces
- H01Q19/12—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces wherein the surfaces are concave
- H01Q19/17—Combinations of primary active antenna elements and units with secondary devices, e.g. with quasi-optical devices, for giving the antenna a desired directional characteristic using reflecting surfaces wherein the surfaces are concave the primary radiating source comprising two or more radiating elements
Landscapes
- Aerials With Secondary Devices (AREA)
- Variable-Direction Aerials And Aerial Arrays (AREA)
Abstract
Description
【発明の詳細な説明】
（技術分野）
本発明は一つのアンテナから複数のビームを独立に放射
できる複数ビームアンテナに関するものであって、例え
ば衛星通信の地球局アンテナとして複数の衛星と通信す
る場合に用いる開口面アンテナに関するものである。[Detailed Description of the Invention] (Technical Field) The present invention relates to a multiple beam antenna that can independently radiate multiple beams from one antenna, and for example, when communicating with multiple satellites as an earth station antenna for satellite communications. The present invention relates to an aperture antenna used for.
（背景技術）
従来、一枚の主反射鏡面から一次放射系の数え対応した
複数のビームを放射するアンテナとしては、それぞれの
目的に合わせて種々の形式が考えられている。一方、衛
星通信の地琴局アンテナとしては個々のビームのビーム
幅に比べ各ビーム相互の間隔が広くとれるアンテナ、言
い換えれば或ルーツのビームに着目した場合にはそのビ
ームを広い角度まで走査しても特性の劣化しないアンテ
ナが必要とされており、衛星の並ぶ面に垂直な軸に対し
て軸対称な構造を有するトーラスアンテナと呼ばれるア
ンテナが有効とされている。第１図に従来考えられてい
るトーラスアンテナの構成を示す。１および１′はそれ
ぞれ一次放射系として用いるホーン、２および２はそれ
ぞれホーン１および１′からの電波を反射する副反射鏡
、３はホーン１および１′からの電波に共通に用いる主
反射鏡、４は主反射鏡３０回転中心軸、５およびダはそ
れぞれホーン１および１′に対応する電波の進行方向を
示す。６は主反射鏡の母線であって略放物線となってお
り、主反射鏡３はこの母線６を回転中心軸４の回りに回
転して得られた曲面により構成される０また、副反射鏡
２およびガは主反射鏡から放射される電波の通路外に配
置され、電波通路を邪魔しないようになっている。本ア
ンテナの動作を送信を例に説明する。ホーン１から出た
電波は副反射鏡２に当り、主反射鏡３の方向に反射され
る。ここで、副反射鏡２は鏡面修整されており、単に電
波の進行方向を折り返すのみならず、主反射鏡がトーラ
ス鏡面であるが故に発生する位相歪を打ち消すように機
能する。副反射鏡２から主反射鏡３に向かった電波は主
反射鏡３で反射され、電波の進行方向５に向かう。同様
に、ホーン１′から出た電波は副反射鏡グ、主反射鏡３
と当り、電波の進行方向ダに向かう。ここで、主反射鏡
３は回転中心軸４に対して回転対称であることに着目す
ると、ホーン１と副反射鏡２の組合せがホーン１１と副
反射鏡／の組合せに対して回転中心軸４回りに回転対称
に配置されれば、ホーン１から出た電波とホーン１′か
ら出た電波とはその最終的な進行方向が異なることを除
き同様の動作をすることは明らかである。このため、主
反射鏡の大きさを十分にとれば、ビーム幅に比べて広い
ビーム相互の間隔を以って複数のビームを配置しても、
それぞれのビームの特性劣化のないアンテナを構成でき
る。これがトーラスアンテナの原理である。ところが、
実際上の要求はただ単にビーム相互の間隔が広くとれれ
ば良いというものではない。衛星が近接して置かれ、地
上からそれぞれの衛星を見込む角度が小さい場合には、
ビーム間隔がビーム幅に比べれば大きくとも、絶対角度
としては数度といった狭い間隔で配置しなければならな
い事態が生ずる。従来のトーラスアンテナではこのよう
な場合に欠点がある。即ち、ビーム間隔をどれだけ近接
できるかは回転中心軸からみた各副反射鏡間の角度をど
れだけ狭くできるかに係っており、ビーム間隔を狭くす
るには副反射鏡を近接して配置しなければならない。と
ころが、然るべき大きさの副反射鏡をそれぞれのビーム
に対して専用に用いているので、ビーム間隔を狭くしよ
うとしても、複数の副反射鏡が相互にぶつかるために、
ある程度以上ビーム間隔を狭くできないという欠点があ
った。このような問題は、副反射鏡径の選び方にもよる
が、概ねビーム間隔を数度以下にしよ５とした場合に起
こってくる。(Background Art) Conventionally, various types of antennas that radiate a plurality of beams corresponding to the primary radiation system from a single main reflecting mirror surface have been considered depending on the purpose. On the other hand, a geokin station antenna for satellite communication is an antenna that allows the spacing between each beam to be wider than the beam width of each individual beam, or in other words, when focusing on a certain root beam, it is possible to scan the beam over a wide angle. There is a need for an antenna whose characteristics do not deteriorate, and an antenna called a torus antenna, which has a structure that is axially symmetrical with respect to an axis perpendicular to the plane where the satellites are lined up, is considered effective. FIG. 1 shows the configuration of a conventional torus antenna. 1 and 1' are horns used as primary radiation systems, 2 and 2 are sub-reflectors that reflect radio waves from horns 1 and 1', respectively, and 3 is a main reflector that is commonly used for radio waves from horns 1 and 1'. , 4 indicates the central axis of rotation of the main reflecting mirror 30, and 5 and DA indicate the traveling directions of radio waves corresponding to the horns 1 and 1', respectively. Reference numeral 6 denotes the generatrix of the main reflecting mirror, which is approximately a parabola. 2 and moth are arranged outside the path of the radio waves emitted from the main reflecting mirror so as not to obstruct the path of the radio waves. The operation of this antenna will be explained using transmission as an example. Radio waves emitted from the horn 1 hit the sub-reflector 2 and are reflected in the direction of the main reflector 3. Here, the sub-reflector 2 has been mirror-finished, and functions not only to simply reflect the direction of propagation of radio waves, but also to cancel phase distortion that occurs because the main reflector is a torus mirror. The radio waves traveling from the sub-reflector 2 to the main reflector 3 are reflected by the main reflector 3 and are directed in the radio wave traveling direction 5. Similarly, the radio waves emitted from the horn 1' are sent to the sub-reflector 3 and the main reflector 3.
When it hits, it heads in the direction of the radio waves. Here, paying attention to the fact that the main reflecting mirror 3 is rotationally symmetrical with respect to the rotation center axis 4, the combination of the horn 1 and the sub-reflector 2 is rotationally symmetrical with respect to the rotation center axis 4. It is clear that if they are arranged rotationally symmetrically, the radio waves emitted from the horn 1 and the radio waves emitted from the horn 1' operate in the same way except that their final traveling directions are different. Therefore, if the main reflector is sufficiently large, even if multiple beams are arranged with a wide beam spacing compared to the beam width,
It is possible to construct an antenna without deterioration of the characteristics of each beam. This is the principle of a torus antenna. However,
A practical requirement is not simply that the beams be spaced widely apart. If the satellites are placed close together and the viewing angle of each satellite from the ground is small,
Even if the beam spacing is large compared to the beam width, a situation may arise where the beams must be arranged at narrow intervals of several degrees in terms of absolute angles. Conventional torus antennas have drawbacks in such cases. In other words, how close the beam spacing can be made depends on how narrow the angle between each sub-reflector seen from the rotation center axis can be.To narrow the beam spacing, it is necessary to place the sub-reflectors close together. Must. However, since a sub-reflector of an appropriate size is used exclusively for each beam, even if you try to narrow the beam spacing, the multiple sub-reflectors will collide with each other, resulting in
There was a drawback that the beam spacing could not be narrowed beyond a certain level. Such a problem depends on how the diameter of the sub-reflecting mirror is selected, but generally occurs when the beam spacing is set to 5 degrees or less.
（発明の目的ン
本発明は以上の欠点を改善することを目的とし、その特
徴は、主反射鏡、副反射鏡、および該副反射鏡に電波を
照射する一次放射系から成り、主反射鏡の鏡面形状、と
じて略放物線から成る母線を主反射鏡から放射される電
波の進行方向と略垂直で主反射鏡前方に位置した軸回り
に回転して得られるトーラス鏡面を用い、前記副反射鏡
を主反射鏡から放射される電波の通路外に配置したトー
ラスアンテナにおいて、前記副反射鏡形状としてトーラ
ス鏡面を用いると共に、主反射鏡を形成するトーラス鏡
面の回転中心軸と前記副反射鏡を形成するｌ・−ラス鏡
面の回転中心軸とを一致させると共に、−次放射系を前
記副反射鏡に比べ回転中心軸から遠くに配置したアンテ
ナ装置にある。(Objective of the Invention) The present invention aims to improve the above-mentioned drawbacks, and its characteristics include a main reflecting mirror, a sub-reflecting mirror, and a primary radiation system that irradiates radio waves to the sub-reflecting mirror. Using a torus mirror surface obtained by rotating a generatrix consisting of a substantially parabola around an axis located in front of the main reflector and approximately perpendicular to the direction of propagation of radio waves emitted from the main reflector, the sub-reflector In a torus antenna in which a mirror is placed outside the path of radio waves emitted from the main reflector, a torus mirror surface is used as the shape of the sub-reflector, and the rotation center axis of the torus mirror surface forming the main reflector is aligned with the sub-reflector. The antenna device is arranged such that the center axis of rotation of the l·-las mirror surface to be formed coincides with the center axis of rotation, and the -order radiation system is placed farther from the center axis of rotation than the sub-reflector.
舅、下、本発明を図面に基づいて詳細に説明する。The present invention will now be described in detail based on the drawings.
（発明の構成及び作用）
第２図は本発明の一実施例であって、７はホーン１およ
び１′から出たそれぞれの電波に対して共用する副反射
鏡であり、その鏡面形状は主反射鏡と同じくトーラス鏡
面となっている。即ち、副反射鏡の母線８を主反射鏡と
同じく回転中心軸４の回りに回転して得られる曲面でで
きている。本アンテナの動作を送信を例にとって説明す
る。ホーン１から出た電波は副反射鏡７に当り、主反射
鏡３の方向に反射され、更に主反射鏡３で反射されて電
波の進行方向５に向かう。同様に、ホーン１′から出た
電波も副反射鏡７、主反射鏡３と当り、電波の進行方向
ダに向かう。ここで、主反射鏡３および副反射鏡７が共
に回転中心軸４に対して回転対称であることに着目する
と、ホーン１がホーンｌ′に対して回転中心軸４回りに
回転対称に配置されれば、ホーン１から出た電波とホー
ン１１から出た電波とはその最終的な進行方向が異なる
ことを除き同様の動作をすることは明らかである。(Structure and operation of the invention) FIG. 2 shows an embodiment of the present invention, in which 7 is a sub-reflector commonly used for the radio waves emitted from the horns 1 and 1', and its mirror surface shape is the main one. Like the reflector, it has a torus mirror surface. That is, it is made of a curved surface obtained by rotating the generating line 8 of the sub-reflecting mirror around the rotation center axis 4 like the main reflecting mirror. The operation of this antenna will be explained using transmission as an example. The radio wave emitted from the horn 1 hits the sub-reflector 7, is reflected in the direction of the main reflector 3, is further reflected by the main reflector 3, and heads in the radio wave traveling direction 5. Similarly, the radio waves emitted from the horn 1' also hit the sub-reflector 7 and the main reflector 3, and are directed in the direction of propagation of the radio waves. Here, paying attention to the fact that both the main reflecting mirror 3 and the sub-reflecting mirror 7 are rotationally symmetrical about the rotational center axis 4, the horn 1 is arranged rotationally symmetrically about the rotational center axis 4 with respect to the horn l'. It is clear that the radio waves emitted from the horn 1 and the radio waves emitted from the horn 11 operate in the same way except that their final traveling directions are different.
従って、本発明は広い角度のビーム走査に対して特性劣
化なしに動作することが理解される。本発明においては
、従来のトーラスアンテナと異なり副反射鏡を共通に用
いており、各ビーム間のビーム間隔の限界はホーンがぶ
つかるか否かで決まることが理解される。ところが、ホ
ーンは副反射鏡に比べて回転中心軸から遠くに置くこと
ができる。Therefore, it is understood that the present invention operates without characteristic deterioration for beam scanning over a wide angle. In the present invention, unlike conventional torus antennas, a sub-reflector is commonly used, and it is understood that the limit of the beam spacing between each beam is determined by whether or not the horns collide. However, the horn can be placed farther from the rotation center axis than the sub-reflector.
従って、回転中心軸からの角度を一定とすればホーンの
配置は楽になり、逆にホーンが接触するまで近づければ
ビーム間隔は狭くすることができる。Therefore, if the angle from the rotation center axis is constant, the arrangement of the horns becomes easier, and conversely, if the horns are brought close together until they touch, the beam spacing can be narrowed.
以上、説明を簡単にするために二つのビームを例に述べ
たが、ビームの数は三つあるいはそれ以上であっても差
し支えない。ビーム数を増やすにはホーンの数を増やせ
ばよい。Although two beams have been described above as an example to simplify the explanation, the number of beams may be three or more. To increase the number of beams, simply increase the number of horns.
本発明において、主反射鏡の母線としては放物線、副反
射鏡の母線としては双曲線あるいは楕円等の二次曲線を
用いるばかりでなく、これ等を目的に応じて修整した曲
線の組合せを用いることができる。特に、ビームの並ん
だ面と垂直な面内での衛星の位置変動を追尾する等の目
的でビームを走査する場合には、双焦点反射鏡と呼ばれ
る反射鏡の断面曲線を用いることは、走査に伴う利得低
下を少なくする上で有効である。また、母線として高能
率修整鏡面の断面曲線を用いることは、アンテナ能率を
向上する上で有効である。双焦点反射鏡はそれぞれの焦
点位置に対して位相歪なくビームを集束することのでき
るもので、その設計法は種々研究されており、そのいず
れを用いても差し支えない。また、高能率修整鏡面の断
面曲線についても設計法は確立しており、当該分野の技
術者には容易に設計できる。In the present invention, it is possible to use not only a parabola as the generatrix of the main reflecting mirror and a quadratic curve such as a hyperbola or an ellipse as the generatrix of the sub-reflector, but also a combination of curves modified according to the purpose. can. In particular, when scanning a beam for the purpose of tracking positional fluctuations of a satellite in a plane perpendicular to the plane where the beams are lined up, it is difficult to use a cross-sectional curve of a reflector called a bifocal reflector. This is effective in reducing the decrease in gain associated with this. Furthermore, using a cross-sectional curve of a highly efficient modified mirror surface as a generating line is effective in improving antenna efficiency. A bifocal reflector is capable of focusing a beam without phase distortion at each focal position, and various design methods have been studied, and any of them may be used. Furthermore, a design method for the cross-sectional curve of a highly efficient modified mirror surface has been established, and can be easily designed by engineers in the field.
第３図は本発明の一実施例であって、ホーン１と集束反
射鏡９より成る一次放射系を示す斜視図である。該−次
放射系は第２図におけるホーン１または１′の代わりに
用いる。ここで、９は主反射鏡３および副反射鏡７で発
生する位相歪を打ち消すための集束反射鏡である。集束
反射鏡９を用いることにより、位相歪をなくし、アンテ
ナ開口能率を高くすることができる。集束反射鏡９の代
わりにレンズを用いても差し支えない。これら集束反射
鏡９またはレンズの設計は光路長一定の条件と呼ばれる
条件式を用いることにより簡単に行うことができる。FIG. 3 is a perspective view showing a primary radiation system comprising a horn 1 and a focusing reflector 9, which is an embodiment of the present invention. The -order radiation system is used in place of horn 1 or 1' in FIG. Here, 9 is a focusing reflector for canceling the phase distortion generated in the main reflector 3 and the sub-reflector 7. By using the focusing reflector 9, phase distortion can be eliminated and antenna aperture efficiency can be increased. A lens may be used instead of the focusing mirror 9. The design of these focusing mirrors 9 or lenses can be easily performed by using a conditional expression called a constant optical path length condition.
（発明の効果）
以上説明したように、本発明により、一枚の主反射鏡か
ら複数のビームの出るアンテナのビーム間隔を狭くでき
るので、これを衛星通信の地球局アンテナとして用いれ
ば衛星の位置が近接していても一台のアンテナで済むの
で、方式の経済化に寄与することカζできる。(Effects of the Invention) As explained above, according to the present invention, it is possible to narrow the beam spacing of an antenna that outputs multiple beams from one main reflecting mirror, so if this is used as an earth station antenna for satellite communication, the satellite position Since only one antenna is required even if the antennas are close to each other, it can contribute to making the system more economical.
第１図は従来のトーラスアンテナの斜視図、第２図は本
発明の一実施例を示す斜視図、第３図は本発明の一実施
例の一次放射系を示す斜視図である。
１．１１・・・ホーン ２，２′・・・副反射鏡３・・
・・・・主反射鏡 ４・・・・・・回転中心軸５．５′
・・・電波の進行方向 ６・・・・・・主反射鏡の母線
７・・・・・・副反射鏡 ８・・・・・・副反射鏡の母
線９・・・・・・集束反射鏡FIG. 1 is a perspective view of a conventional torus antenna, FIG. 2 is a perspective view showing an embodiment of the present invention, and FIG. 3 is a perspective view showing a primary radiation system of an embodiment of the present invention. 1.11...Horn 2,2'...Sub-reflector 3...
...Main reflecting mirror 4 ...Rotation center axis 5.5'
... Direction of radio wave travel 6 ... Generatrix of main reflector 7 ... Sub-reflector 8 ... Generatrix of sub-reflector 9 ... Focused reflection mirror
Claims (4)
照射する一次放射系から成り、主反射鏡の鏡面形状とし
て略放物線から成る母線を主反射鏡から放射される電波
の進行方向と略垂直で主反射鏡前方に位置した軸回りに
回転して得られるトーラス鏡面を用い、前記副反射鏡を
主反射鏡から放射される電波の通路外に配置したトーラ
スアンテナにおいて、前記副反射鏡形状としてトーラス
鏡面を用いると共に、主反射鏡を形成するトーラス鏡面
の回転中心軸と前記副反射鏡を形成するトーラス鏡面の
回転中心軸とを一致させると共に、−次放射系を前記副
反射鏡に比べ回転中心軸から遠くに配置したことを特徴
とするアンテナ装置。(1) Consisting of a main reflecting mirror, a sub-reflecting mirror, and a primary radiation system that irradiates radio waves to the sub-reflecting mirror, the radio waves radiated from the main reflecting mirror progress along a generatrix that is approximately a parabola as the mirror surface shape of the main reflecting mirror. In a torus antenna that uses a torus mirror surface obtained by rotating around an axis located in front of the main reflector and substantially perpendicular to the direction, the sub reflector is placed outside the path of radio waves radiated from the main reflector. A torus mirror surface is used as the reflecting mirror shape, and the center axis of rotation of the torus mirror surface forming the main reflecting mirror is made to coincide with the center axis of rotation of the torus mirror surface forming the sub reflecting mirror. An antenna device characterized by being placed farther from the rotation center axis than a mirror.
の母線として双焦点アンテナ鏡面の断面曲線としてめら
れる主反射鏡および副反射鏡の曲線形状をそれぞれ用い
たことを特徴とする特許請求範囲第１項に記載のアンテ
ナ装置。(2) A claim characterized in that the curved shapes of the main reflector and the sub-reflector, which can be seen as the cross-sectional curve of the bifocal antenna mirror surface, are used as the generatrix of the torus mirror surface forming the main reflector and the sub-reflector, respectively. The antenna device according to item 1.
の母線として高能率修整鏡面の断面曲線としてめられる
主反射鏡および副反射鏡の曲線形状をそれぞれ用いたこ
とを特徴とする特許請求範囲第１項に記載のアンテナ装
置。(3) The scope of the patent characterized in that the curved shapes of the main reflecting mirror and the sub-reflecting mirror, which can be seen as the cross-sectional curves of the highly efficient modified mirror surfaces, are used as the generatrix of the torus mirror surface forming the main reflecting mirror and the sub-reflecting mirror, respectively. The antenna device according to item 1.
を打ち消すように鏡面修整された少なくとも一枚以上の
反射鏡またはレンズを備えた一次放射系を用いることを
特徴とする特許請求の範囲第１項ないし第３項のいずれ
か一項に記載のアンテナ装置。(4) A primary radiation system comprising at least one reflecting mirror or lens whose surface has been mirror-finished so as to cancel phase distortion caused by the main reflecting mirror and the sub-reflecting mirror. The antenna device according to any one of Items 1 to 3.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15631583A JPS6048603A (en) | 1983-08-29 | 1983-08-29 | Antenna system |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP15631583A JPS6048603A (en) | 1983-08-29 | 1983-08-29 | Antenna system |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS6048603A true JPS6048603A (en) | 1985-03-16 |
| JPH053762B2 JPH053762B2 (en) | 1993-01-18 |
Family
ID=15625110
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP15631583A Granted JPS6048603A (en) | 1983-08-29 | 1983-08-29 | Antenna system |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS6048603A (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03191604A (en) * | 1989-12-20 | 1991-08-21 | Mitsubishi Electric Corp | Antenna equipment |
| WO2019170541A1 (en) * | 2018-03-05 | 2019-09-12 | Technische Universiteit Eindhoven | Extreme scanning focal-plane arrays using a double-reflector concept with uniform array illumination |
-
1983
- 1983-08-29 JP JP15631583A patent/JPS6048603A/en active Granted
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH03191604A (en) * | 1989-12-20 | 1991-08-21 | Mitsubishi Electric Corp | Antenna equipment |
| WO2019170541A1 (en) * | 2018-03-05 | 2019-09-12 | Technische Universiteit Eindhoven | Extreme scanning focal-plane arrays using a double-reflector concept with uniform array illumination |
Also Published As
| Publication number | Publication date |
|---|---|
| JPH053762B2 (en) | 1993-01-18 |
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