JPH0642612B2 - Free-standing primary radiator for reflector antenna - Google Patents
Free-standing primary radiator for reflector antennaInfo
- Publication number
- JPH0642612B2 JPH0642612B2 JP63035340A JP3534088A JPH0642612B2 JP H0642612 B2 JPH0642612 B2 JP H0642612B2 JP 63035340 A JP63035340 A JP 63035340A JP 3534088 A JP3534088 A JP 3534088A JP H0642612 B2 JPH0642612 B2 JP H0642612B2
- Authority
- JP
- Japan
- Prior art keywords
- primary radiator
- cap
- reflector
- waveguide
- reflecting mirror
- 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.)
- Expired - Lifetime
Links
Landscapes
- Aerials With Secondary Devices (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 本発明は、反射鏡アンテナの一次放射器として用いられ
る自立型一次放射器に関する。TECHNICAL FIELD The present invention relates to a self-standing primary radiator used as a primary radiator of a reflector antenna.
一般に自立型一次放射器１は、第３図に示すように小口
径の主反射鏡２を含むアンテナの一次放射器として用い
られており、電波は給電用導波管３の開口部４に取り付
けられたキャップ状反射部５から反射して主反射鏡２に
放射する構造となっている。反射部５を均一な樹脂でで
きたキャップ固定用カバー６等で導波管３に固定するこ
とにより、カセグレンアンテナなどの副反射鏡を、金属
性支柱で固定した反射鏡アンテナに比較して支柱からの
散乱や副反射鏡のブロッキングによる放射界への悪影響
を小さくすることができる。Generally, the self-standing primary radiator 1 is used as a primary radiator of an antenna including a small-diameter main reflecting mirror 2 as shown in FIG. 3, and radio waves are attached to an opening 4 of a power feeding waveguide 3. It has a structure in which it is reflected from the cap-shaped reflecting portion 5 and emitted to the main reflecting mirror 2. By fixing the reflection part 5 to the waveguide 3 with a cap fixing cover 6 made of a uniform resin, a sub-reflecting mirror such as a Cassegrain antenna is supported as compared with a reflecting mirror antenna fixed by a metal supporting column. It is possible to reduce the adverse effect on the radiation field due to scattering from light and blocking of the subreflector.
なお、従来の自立型一次放射器に関するものとして、例
えば特公昭58−21847号公報が挙げられる。As a conventional self-standing primary radiator, for example, Japanese Patent Publication No. 58-21847 can be cited.
〔発明が解決しようとする課題〕 従来の自立型一次放射器は、第２図に示すように、給電
用導波管３の開口部４に、キャップ状反射部５を取り付
けた構造となっている。[Problems to be Solved by the Invention] As shown in FIG. 2, a conventional self-standing primary radiator has a structure in which a cap-shaped reflecting portion 5 is attached to an opening 4 of a feeding waveguide 3. There is.
第３図に示すように、この一次放射器１を、主反射鏡２
の中央に設置し、キャップ状の反射部から、主反射鏡２
に向って電波を放射する反射鏡アンテナを構成すること
ができる。As shown in FIG. 3, the primary radiator 1 is connected to the main reflecting mirror 2
Installed in the center of the
It is possible to configure a reflector antenna that radiates radio waves toward.
しかし、上記反射部は、壁面電流の回り込み等により、
後方に不要な放射界を生じる。このため、反射鏡アンテ
ナを構成した場合、主反射鏡から反射して正面方向に向
かう放射界に、一次放射器からの不要な放射界が影響を
与え、全体の放射パターンの一部のレベルに落ち込みが
生じる等、パターンが乱れるという問題があった。However, the above-mentioned reflection part, due to the sneak of wall current,
An unnecessary radiation field is generated behind. For this reason, when a reflector antenna is configured, the unwanted radiation field from the primary radiator affects the radiation field reflected from the main reflecting mirror and traveling in the front direction, and the radiation field at a part of the overall radiation pattern is affected. There is a problem that the pattern is disturbed such as a drop.
本発明の課題は、反射鏡アンテナを構成する場合、放射
パターンの一部にレベルの落ち込み等によって生じるパ
ターンの乱れを小さくすることにある。An object of the present invention is to reduce the disturbance of the pattern caused by a drop in the level of a part of the radiation pattern when the reflector antenna is constructed.
上記課題を解決するため本発明は、反射鏡アンテナの一
次放射器として用いられる導波管の開口部にキャップ状
の反射部を取り付けた構造の自立型一次放射器におい
て、キャップの外周に円筒状のみぞを設けた。In order to solve the above problems, the present invention relates to a self-standing primary radiator having a structure in which a cap-shaped reflector is attached to an opening of a waveguide used as a primary radiator of a reflector antenna, in which a cylindrical shape is provided around the outer periphery of the cap. I provided a groove.
自立型一次放射器から後方に放射される不要な放射界の
波源のひとつに、キャップ状の反射部の外周にまわり込
む壁面電流がある。この壁面電流を小さくするために、
キャップ状の反射部の外周に円筒状のぞみを装荷する。One of the unnecessary radiation field sources radiated backward from the self-supporting primary radiator is the wall current that wraps around the outer periphery of the cap-shaped reflector. In order to reduce this wall current,
A cylindrical nose is loaded on the outer periphery of the cap-shaped reflector.
みぞの深さは、自由空間波長の1/4程度とし、みぞの幅
を自由空間波長に対して充分小さくとると、このみぞの
表面インピーダンスは非常に大きくなる。給電用導波管
を伝搬してきた電磁波は、キャップ状の反射部で反射す
るとき、壁面電流がキャップの外側にまわり込みにくく
なり、反射部後方に放射される不要な放射界が小さくな
る。このため反射鏡に取り付けた場合、アンテナの放射
パターンの乱れが小さくなるような一次放射器が得られ
る。If the depth of the groove is about 1/4 of the free space wavelength and the width of the groove is sufficiently small with respect to the free space wavelength, the surface impedance of this groove becomes very large. When the electromagnetic wave propagating through the power feeding waveguide is reflected by the cap-shaped reflector, the wall current is less likely to wrap around the outside of the cap, and an unnecessary radiation field radiated behind the reflector is reduced. Therefore, when it is attached to a reflecting mirror, a primary radiator is obtained in which the disturbance of the radiation pattern of the antenna is reduced.
以下第１図に、反射鏡アンテナの放射器として使用する
自立型一次放射器の一実施例を示す。FIG. 1 shows an embodiment of a self-standing primary radiator used as a radiator of a reflector antenna.
給電用の導波管として円形導波管３を用い、この導波管
の開口部４に、キャップ状反射部５を取り付けている。
円形導波管内を伝搬してきた電磁波は、この反射部５で
反射して、一次放射器の正面方向（中心軸方向）７に放
射する。反射部５は、中央にV.S.W.R.を良好に保つため
の整合部８を設け、反射部の外周には、壁面電流の回り
込みを抑えるための円筒状の溝９を設けている。A circular waveguide 3 is used as a power feeding waveguide, and a cap-shaped reflecting portion 5 is attached to an opening 4 of this waveguide.
The electromagnetic wave propagating in the circular waveguide is reflected by the reflecting portion 5 and radiated in the front direction (center axis direction) 7 of the primary radiator. The reflector 5 is provided with a matching portion 8 for maintaining a good VSWR in the center, and a cylindrical groove 9 is provided on the outer periphery of the reflector 5 for suppressing the sneak of wall surface current.
溝の深さを自由空間波長の1/4程度、溝の幅を1/15程度
とすれば、表面のインピーダンスは非常に大きくなり、
反射部の内壁から外壁に向かう電流が小さくなる。この
ため、反射部の開口から後方に向かう不要な放射界の量
を小さく抑えることができる。If the depth of the groove is about 1/4 of the free space wavelength and the width of the groove is about 1/15, the impedance of the surface becomes very large,
The current flowing from the inner wall to the outer wall of the reflecting portion becomes small. For this reason, it is possible to reduce the amount of unnecessary radiation field that goes rearward from the opening of the reflecting portion.
本発明によれば、反射鏡アンテナの一次放射器として用
いられる導波管の開口部にキャップ状の反射部を取り付
けた自立型の一次放射器において、反射部の外周に円筒
状の溝を設け反射部の開口から後方に放射される不要な
放射界の量を小さくすることができ、反射鏡アンテナの
放射パターンの乱れが小さくなるような一次放射器を構
成することができる。According to the present invention, in a self-standing primary radiator in which a cap-shaped reflector is attached to the opening of a waveguide used as the primary radiator of a reflector antenna, a cylindrical groove is provided on the outer periphery of the reflector. It is possible to reduce the amount of unnecessary radiation field radiated rearward from the opening of the reflecting portion, and to configure a primary radiator that reduces disturbance of the radiation pattern of the reflector antenna.
第１図は本発明の一実施例の自立型一次放射器を示し、
(a)はキャップ状反射部の正面図、(b)は縦断面である。 第２図は従来の自立型一次放射器の縦断面図、第３図は
主反射鏡の中心軸上に自立型一次放射器を取り付けた構
造の従来型開口面アンテナの概略図である。 １…自立型一次放射器 ２…主反射鏡 ３…給電用導波管 ４…導波管の開口部 ５…キャップ状反射部 ６…キャップ固定用カバー ７…自立型一次放射器の正面方向 ８…V.S.W.R.整合部 ９…円筒状の溝 １０…自立型一次放射器の後方。FIG. 1 shows a free-standing primary radiator according to an embodiment of the present invention,
(a) is a front view of the cap-shaped reflecting portion, and (b) is a vertical section. FIG. 2 is a vertical cross-sectional view of a conventional self-standing primary radiator, and FIG. 3 is a schematic view of a conventional aperture antenna having a structure in which the self-standing primary radiator is mounted on the central axis of the main reflecting mirror. DESCRIPTION OF SYMBOLS 1 ... Self-standing primary radiator 2 ... Main reflecting mirror 3 ... Feeding waveguide 4 ... Waveguide opening 5 ... Cap-shaped reflecting portion 6 ... Cap fixing cover 7 ... Self-standing primary radiator front direction 8 … VSWR matching part 9… Cylindrical groove 10… Behind self-standing primary radiator.
Claims (1)
アンテナの一次放射器として用いられる給電用導波管
と、該導波管の開口部に対抗して設けられたキャップ状
の反射部とを具えた自立型一次放射器において、前記キ
ャップ状の反射部の内壁にかつ外周に前記導波管と同一
向きで、該反射部の表面のインピーダンスが大きくなっ
て反射部の内壁から外壁に向かう電流が小さくなるよう
な円筒状のみぞを設け、前記円筒状のみぞをもって前記
反射部の整合部側の開口から該反射部の後方に向かう不
要な放射界の量を抑えてなることを特徴とする反射鏡ア
ンテナの一次放射器。1. A main reflecting mirror, a feeding waveguide provided on the main reflecting mirror and used as a primary radiator of a reflecting mirror antenna, and a cap-like member provided so as to oppose an opening of the waveguide. In a self-supporting primary radiator having a reflection part of, the inner wall of the reflection part is formed by increasing the impedance of the surface of the reflection part in the same direction as the waveguide on the inner wall of the cap-shaped reflection part and on the outer circumference. A cylindrical groove is provided so that the current flowing from the reflector to the outer wall is small, and the cylindrical groove suppresses the amount of unnecessary radiation field from the opening on the matching portion side of the reflecting portion toward the rear of the reflecting portion. A primary radiator of a reflector antenna, which is characterized in that
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63035340A JPH0642612B2 (en) | 1988-02-19 | 1988-02-19 | Free-standing primary radiator for reflector antenna |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP63035340A JPH0642612B2 (en) | 1988-02-19 | 1988-02-19 | Free-standing primary radiator for reflector antenna |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH01212102A JPH01212102A (en) | 1989-08-25 |
| JPH0642612B2 true JPH0642612B2 (en) | 1994-06-01 |
Family
ID=12439125
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP63035340A Expired - Lifetime JPH0642612B2 (en) | 1988-02-19 | 1988-02-19 | Free-standing primary radiator for reflector antenna |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0642612B2 (en) |
Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP5854888B2 (en) * | 2011-08-29 | 2016-02-09 | 三菱電機株式会社 | Primary radiator and antenna device |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5934163Y2 (en) * | 1976-10-12 | 1984-09-21 | 八木アンテナ株式会社 | Primary radiator for parabolic antenna |
| JPS5739603A (en) * | 1980-08-21 | 1982-03-04 | Toshiba Corp | Effective area antenna |
| JPS62202605A (en) * | 1986-02-28 | 1987-09-07 | Nec Corp | Primary radiator for reflection mirror antenna |
-
1988
- 1988-02-19 JP JP63035340A patent/JPH0642612B2/en not_active Expired - Lifetime
Also Published As
| Publication number | Publication date |
|---|---|
| JPH01212102A (en) | 1989-08-25 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| EXPY | Cancellation because of completion of term |