JP3846585B2

JP3846585B2 - Waveguide bend, waveguide plate and high frequency device

Info

Publication number: JP3846585B2
Application number: JP2002333035A
Authority: JP
Inventors: 拓也鈴木; 努田牧
Original assignee: Mitsubishi Electric Corp
Current assignee: Mitsubishi Electric Corp
Priority date: 2002-11-18
Filing date: 2002-11-18
Publication date: 2006-11-15
Anticipated expiration: 2022-11-18
Also published as: JP2004172688A

Description

【０００１】
【発明の属する技術分野】
この発明は、導波管ベンドに関し、特にマイクロ波帯及びミリ波帯等の導波管給電回路、導波管を用いて信号の送受信を行う高周波モジュールなどに用いる導波管回路に関するものである。
【０００２】
【従来の技術】
従来の導波管ベンドは、互いに管軸方向が異なる導波管の接続部において、導波管内の電磁波の伝搬方向を曲げ、方向に沿って不要な反射を生じさせることなくスムーズに伝搬させるために、導波管を所望の角度で曲げ形成し、その曲げ部の外側内面を階段状のステップ面を形成している（例えば特許文献１参照）。
【０００３】
また、上記と同等の効果を得られるように曲げ部の外側内面をテーパ状に形成したものもある（例えば、非特許文献１）。
【０００４】
しかしながら、上記のような導波管曲げ部のステップ面は、導波管の管軸に対して並行及び垂直な面を交互に連続させた複数段の階段面を切削する必要があり、高い加工精度が要求される。上記のような回路をマイクロ波帯、ミリ波帯で作る場合は、その波長が小さくなっていくため、これに伴い導波管およびステップ面の寸法も小さくなってくる。
例えば、Ｗバンド（７５ＧＨｚ〜１１０ＧＨｚ）での導波管寸法は、２．５４ｍｍ×１．２７ｍｍ（ＷＲ−１０）となり、この周波数帯における導波管ステップ面は、１．２７ｍｍを複数段に分割した微小な階段面（例えば、３段の場合、０．３ｍｍ〜０．４ｍｍ）に切削する高精度な加工が必要になる。
【０００５】
また、２枚の導体板を用いて、切削加工などにより一方の導体板に水平方向へ伝送する単一あるいは複数の導波管溝を形成し、上記導体板およびもう一方の導体板に導波管溝の両端から上下面方向に伝送する導波管を形成して、これらの２枚の導体版を張り合わせて、一方の導波管から他方の導波管へ高周波信号を伝える導波管プレートにおいて、上記各々の水平方向と上下面方向の導波管が直交するコーナー部へ上記の導波管ベンドを構成しようとした場合、ステップ面は導波管溝を形成した導体板へ形成する必要がある。
この場合、一方のコーナー部へステップ面を形成することは可能であるが、上下面方向に導波管を有する側のコーナー部に対しては、導波管溝を形成した側からステップ面の加工は不可能であり、かつ反対側からの加工は上下面方向に形成した導波管内を通して切削加工となるため、非常に精度が要求され、加工が困難である。
【０００６】
さらに、上記のような複数の導波管をより安価に形成するための加工方法として、従来から使われている射出成型などが考えられるが、当該構造のように導波管の内壁から突出したステップ面の加工は、抜き構造のみ形成可能な射出成型では成型不可能である。
【０００７】
【特許文献１】
特開平９−２４６８０１号公報（第２−４頁、第１図）
【非特許文献１】
GEORGE L.RAGAN,"MICROWAVE TRANSMISSION CIRCUITS",
1948 McGRAW-HILL,p203-207
【０００８】
【発明が解決しようとする課題】
従来の導波管ベンドは、以上のように構成されており、必要な電気特性を得るために、各導波管曲げ部のステップ面の加工に対して機械的に非常に高い加工精度、面精度が要求されていたため、加工費が非常に高価であるという問題があった。また、導波管ベンドとして導波管内壁を突出させる構成となっているために、低コスト化が期待できる射出成型などの加工方法を採用できないという加工上の制約も多かった。
【０００９】
この発明は、上記のような問題点を解決するために成されたものであり、広帯域な周波数範囲に渡って低損失で、位相変化の少ない良好な通過特性など、必要な電気特性確保のために要求される機械加工精度や製造コストを大幅に低減させることができ、かつ当該構造によって受ける加工上の制約を無くすことが可能な構造を持つ導波管ベンドを得ることを目的とする。
【００１０】
【課題を解決するための手段】
上記の目的を達成するために、この発明に係る導波管ベンドは、導波管内の電磁波の伝搬方向を進行方向から異なる管軸方向に変換する導波管コーナー部において、管軸方向が異なる導波管のいずれか一方、あるいは双方のコーナーから外側に向けて、当該いずれか一方、あるいは双方の導波管と連通すると共に、所望の波長の電磁波を伝搬させる際に、前記導波管コーナー部内かつ反射が生じない位置に電気的短絡面を形成させるキャビティを有したものである。
【００１１】
また、この発明に係る導波管プレートは、２枚の導体板を用いて上下面方向から水平方向に高周波信号を伝送させるために形成した単一あるいは複数の導波管を有し、上記各々の導波管コーナー部に面方向か水平方向に形成された導波管のどちらか一方、あるいは双方のコーナーから外側に向けて当該いずれか一方、あるいは双方の導波管と連通するとともに、所望の波長の電磁波を伝搬させる際に、前記導波管コーナー部内かつ反射が生じない位置に電気的短絡面を形成させるキャビティを有したものである。
【００１２】
また、この発明に係る高周波装置は、上記導波管プレートを搭載し、導波管プレートとの間で入力もしくは出力されるミリ波やマイクロ波等の高周波信号を送信または受信する手段を備えたものである。
【００１３】
【発明の実施の形態】
実施の形態１．
図１は、この発明の実施の形態１を示す導波管ベンドの斜視図である。図において、導波管１と導波管２は管軸が直交しており、２つの導波管接続部において、導波管のいずれか一方、あるいは双方のコーナー部外側導体壁端面を延長させてキャビティ５を形成している。また、図２（ａ）〜（ｄ）は、切削加工などにより、２つの金属板４ａ，４ｂ内に形成した導波管及び導波管ベンドをＨ面の中心で切断した各種形態による断面図、図３（ａ）は図２の断面詳細図を示しており、切削加工などにより金属板４ａ，４ｂに導波管１，２を形成し、導波管接続部において、導波管のいずれか一方、あるいは双方のコーナー部外側導体壁端面６を延長させて形成したキャビティ５を形成している。また、図３（ｂ）では導波管コーナー部に励振される電界（定在波）の分布を示している。図中の導波管１と２は直角（管軸が直交となるように）に曲げを形成した例を示している。
【００１４】
次に動作について説明する。一般に曲折した導波管接続部では、伝送系のインピーダンスに対して不整合となる直列インダクタンスと並列容量が付加されるために反射が生じる。この導波管曲げ部の外側内面を図３のＣ−Ｃ部に示すように、導波管寸法に対して適当な寸法Ｌｃを持つ１段あるいは複数段のステップ面３を形成し、その導体壁面（電気的な短絡面）の位置を変化させ、伝送系のインピーダンスに対して反射の生じないような直列インダクタンスと並列容量を持たせることにより、導波管内を伝送する広帯域な周波数範囲にわたって反射を抑制し、かつ低損失で位相変化の少ない導波管伝送系を形成することが可能である。
【００１５】
図１及び図２（ａ）〜（ｄ）において、導波管１および２の接続部において、導波管のどちらか一方、あるいは双方のコーナー部外側導体壁端面６を延長させて形成したキャビティ５，５ａ〜５ｄを設けているが、上記キャビティ５，５ａ〜５ｄはいずれも上記のステップ面と等価的な役割を果たしている。
すなわち、図３（ｂ）において、マイクロ波、ミリ波などの電磁波は伝送系において導波管内波長の１／２の周期で一定の分布（定在波分布）を示すため、キャビティ５は導体壁端面６を短絡面とし、この位置からキャビティ内の管内波長の１／２ごとに仮想的な電気的短絡面を形成する。
【００１６】
図３（ａ）のキャビティ寸法（導波管１の内壁端面からキャビティ導体端面６までの距離Ｌ）は、この仮想的な電気的短絡面が上記のステップ面で形成した短絡面Ｃ−Ｃ（導波管１の内壁端面から距離Ｌｃだけ突出した位置）と同等となるように選ばれており、キャビティ内の管内波長の１／２の長さからＬｃ分だけ短い長さとなっている。このため、キャビティ５によって導波管曲げ部ではステップ面と等価な直列インダクタンスと並列容量が得られ、導波管１から導波管２へ伝搬する電磁波の方向を曲げ、所望信号帯域内では不要な反射を生じさせることなく、スムーズに電磁波を伝搬させることができる。
【００１７】
キャビティ寸法は上記Ｌが最小の長さとなるが、Ｌに管内波長の１／２の整数倍を加えた場合も同様に短絡面が形成されるため、ほぼ同等の特性が得られる。
また、キャビティ形状は、図３では金属板４ａ側にのみ直方体のキャビティ５を形成する例を示しているが、図２（ａ）〜（ｄ）の５ａ〜５ｄに示すようにキャビティ形状は、仮想的な電気的短絡面が図中のＣ−Ｃ部と等価になるように選ばれれば、どのような形状であっても良い。
【００１８】
さらに、図においてはＥ面の導波管ベンドを用いた構成を示しているが、Ｈ面の導波管ベンドを構成する場合も仮想的な電気的短絡面となる寸法を持つキャビティを構成により実現可能である。
【００１９】
上記のような導波管ベンド構成とすることで、導波管モードとして伝送する広帯域な周波数範囲にわたって反射を抑圧することが可能であり、低損失で、位相変化の少ない導波管伝送系を形成することができる。
【００２０】
また、上記導波管ベンドは従来の導波管曲げ部のステップ面のように、微小で複雑な構造をしていないため、高精度な切削加工が不要である。
【００２１】
さらに、２つの金属板４ａ，４ｂを用いて導波路を形成する場合、それぞれに金属板に成形する導波管はすべて抜き構造となっているため、プレス加工や射出成型による製造も可能であり、大幅な製造コストの低減が期待できる。
【００２２】
実施の形態２．
図４は、この発明の実施の形態２を示す導波管プレートの斜視図である。図５は、図４のＤ−Ｄ部における導波管プレートの断面図である。図において、導波管プレート４ａ，４ｂは上下面方向にマイクロ波帯及びミリ波帯等の各周波数帯の高周波信号を導波管モードで伝送する導波管１ａ，１ｂおよび水平方向に伝送する導波管２が複数設けられており、例えば、同一平面内に複数の導波管を持つ高周波デバイス１０と平面アンテナ１１とをそれぞれ導波管接続するインタフェースとして用いられ、各々のプレートに設けられた対向する複数の導波管間との高周波信号を伝送させる。
【００２３】
なお、図５においては、高周波デバイスと平面アンテナとの接続例を示しているが、高周波モジュール同士、あるいは高周波モジュールと導波管治具などの一部となる導波管接続構造としても用いることが可能である。この際、互いに管軸方向が異なる導波管１ａ及び導波管２、導波管１ｂおよび導波管２を接続し、所望信号帯域内では不要な反射を生じさせることなく、スムーズに電磁波を伝搬させるため、その曲げ部の外側内面にテーパ面７および、キャビティ５ａ，５ｂが設けられている。
【００２４】
キャビティ５ａ，５ｂは、実施の形態１で示した図１〜図３の導波管ベンドと同様にキャビティ端を短絡面とし、この位置から自由空間波長の１／２ごとに仮想的な電気的短絡面を形成する。
キャビティ寸法は、この仮想的な電気的短絡面が導波管曲げ部のステップ面と同等となるように選ばれており、キャビティによって導波管曲げ部ではステップ面と等価な直列インダクタンスと並列容量が得られるため、導波管１から導波管２へ伝搬する電磁波の方向を曲げ、導波管モードとして伝送する広帯域な周波数範囲にわたって反射を抑圧し、低損失で、位相変化の少ない導波管伝送系を形成することができる。
【００２５】
また、複数の導波管伝送系を同一平面内に構成することで、一括して伝送線路の加工・成型が可能であるため、大幅な製造コストの低減が可能である。
【００２６】
さらに、上記キャビティを用いた導波管ベンド構成により機械加工精度の要求を大幅に緩和させることができ、ダイカスト成型やプレス加工などの安価な加工法で良好な電気特性を得る導波管プレートを製造することも可能である。
【００２７】
実施の形態３．
この発明の実施の形態３では、実施の形態２の導波管プレートとの間で、入力もしくは出力されるミリ波やマイクロ波等の高周波電波を、送信または受信する高周波装置について述べる。この高周波装置として、例えばミリ波帯のＲＦ信号を送信し、周囲からの反射波を受信することによって周囲に存在する物体までの距離や方向を計測するミリ波レーダや、マイクロ波の通信信号を送信する送信機或いはマイクロ波の通信信号を受信する受信機を備えたマイクロ波通信装置や、ミリ波帯の送信ビームを走査し、受信波から画像を生成して、周囲に存在する物体のビデオ画像を得るミリ波画像装置等がある。
【００２８】
図５に示した導波管プレートにおいて、高周波のＲＦ信号を入出力する入出力端子１ａ，１ｂ，２を、平面アンテナ１１や高周波デバイス１０等に接続する。特に、ミリ波帯（３０ＧＨｚ〜３００ＧＨｚ）などの伝送損失が問題となる周波数帯においては、上記のように複数の導波管を有する導波管プレートを小型・集積化された高周波パッケージから平面アンテナなどの外部インタフェースとして活用することで、高周波パッケージ内の伝送線路として通常用いられるマイクロストリップ線路やトリプレート線路などの平面線路に比べて、大幅な線路損失の低減を図ることが可能であり、アレイ（送受信チャネルの複数化）化やモジュール構造の多彩化に大きく貢献できる。
また、機械加工精度の要求が緩和されるために、従来の機械加工品に比べて、高周波装置全体として低コストな装置を構成することが可能である。
【００２９】
【発明の効果】
この発明によれば、導波管内の電磁波の伝搬方向を進行方向から異なる管軸方向に変換する導波管コーナー部において、管軸方向が異なる導波管のいずれか一方、あるいは双方のコーナーから外側に向けて、当該いずれか一方、あるいは双方の導波管と連通すると共に、所望の波長の電磁波を伝搬させる際に、前記導波管コーナー部内かつ反射が生じない位置に電気的短絡面を形成させるキャビティを有したことにより、広帯域な周波数範囲にわたって低損失で、位相変化の少ない良好な通過特性を持つと共に、機械加工精度や製造コストを大幅に低減可能な導波管ベンドを得ることができる。
【図面の簡単な説明】
【図１】この発明の実施の形態１を示す導波管ベンドの斜視図である。
【図２】この発明の実施の形態１を示す導波管ベンドの断面図である。
【図３】この発明の実施の形態１を示す導波管ベンドの断面詳細図およびコーナー部の電界（定在波）分布である。
【図４】この発明の実施の形態２を示す導波管プレートの斜視図である。
【図５】この発明の実施の形態２を示す導波管プレートの斜視図である。
【符号の説明】
１，１ａ，１ｂ上下面方向に進行する導波管、
２導波管１，１ａ，１ｂに管軸が直交する導波管、３階段状のステップ面、
４ａ，４ｂ各導波管を形成するための金属板、
５，５ａ〜５ｄキャビティ、６キャビティ５の導体壁端面、７テーパ面、
１０マイクロ波・ミリ波帯の高周波デバイス、
１１マイクロ波・ミリ波帯の平面アンテナ。[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a waveguide bend, and more particularly, to a waveguide feeding circuit in a microwave band and a millimeter wave band, and a waveguide circuit used in a high-frequency module that transmits and receives signals using a waveguide. .
[0002]
[Prior art]
In conventional waveguide bends, the propagation direction of electromagnetic waves in the waveguide is bent at the connection part of the waveguides with different tube axis directions, and smoothly propagates without causing unnecessary reflection along the direction. Further, the waveguide is bent at a desired angle, and a stepped step surface is formed on the outer inner surface of the bent portion (see, for example, Patent Document 1).
[0003]
In addition, there is one in which the outer inner surface of the bent portion is formed in a tapered shape so as to obtain the same effect as described above (for example, Non-Patent Document 1).
[0004]
However, the step surface of the waveguide bending section as described above needs to cut a plurality of stepped surfaces in which planes parallel and perpendicular to the tube axis of the waveguide are alternately continued, which is highly processed. Precision is required. When the circuit as described above is made in the microwave band and the millimeter wave band, the wavelength becomes smaller, and accordingly, the dimensions of the waveguide and the step surface also become smaller.
For example, the waveguide size in the W band (75 GHz to 110 GHz) is 2.54 mm × 1.27 mm (WR-10), and the waveguide step surface in this frequency band is 1.27 mm divided into multiple stages. Therefore, it is necessary to perform high-accuracy machining to cut the fine step surface (for example, 0.3 mm to 0.4 mm in the case of three steps).
[0005]
In addition, by using two conductor plates, a single or a plurality of waveguide grooves that transmit in the horizontal direction are formed in one conductor plate by cutting or the like, and guided to the conductor plate and the other conductor plate. A waveguide plate that transmits a high-frequency signal from one waveguide to the other by forming a waveguide that transmits in the vertical direction from both ends of the tube groove, and laminating these two conductor plates In step 1, the step surface must be formed on the conductor plate in which the waveguide groove is formed when trying to construct the waveguide bend at the corner where the horizontal and vertical waveguides are orthogonal to each other. There is.
In this case, it is possible to form a step surface on one corner, but for the corner on the side having the waveguide in the vertical direction, the step surface is formed from the side where the waveguide groove is formed. Processing is impossible, and processing from the opposite side is performed by cutting through the waveguide formed in the upper and lower surface directions, so that very high accuracy is required and processing is difficult.
[0006]
Further, as a processing method for forming a plurality of waveguides as described above at a low cost, conventionally used injection molding or the like is conceivable, but it protrudes from the inner wall of the waveguide as in the structure. The processing of the step surface cannot be performed by injection molding that can form only a punched structure.
[0007]
[Patent Document 1]
JP-A-9-246801 (page 2-4, FIG. 1)
[Non-Patent Document 1]
GEORGE L.RAGAN, "MICROWAVE TRANSMISSION CIRCUITS",
1948 McGRAW-HILL, p203-207
[0008]
[Problems to be solved by the invention]
The conventional waveguide bend is configured as described above, and in order to obtain the required electrical characteristics, the machining accuracy and surface are extremely high mechanically with respect to the step surface of each waveguide bending portion. Since the accuracy was required, there was a problem that the processing cost was very expensive. In addition, since the waveguide inner wall protrudes as a waveguide bend, there are many processing restrictions that a processing method such as injection molding that can be expected to reduce the cost cannot be adopted.
[0009]
The present invention has been made to solve the above-described problems, in order to ensure necessary electrical characteristics such as good pass characteristics with low loss and little phase change over a wide frequency range. It is an object of the present invention to obtain a waveguide bend having a structure that can greatly reduce the machining accuracy and manufacturing cost required for the above-described structure and can eliminate the processing restrictions imposed by the structure.
[0010]
[Means for Solving the Problems]
In order to achieve the above object, the waveguide bend according to the present invention is different in the tube axis direction at the waveguide corner that converts the propagation direction of the electromagnetic wave in the waveguide from the traveling direction to a different tube axis direction. The waveguide corner communicates with either one or both of the waveguides outward from the corners of either or both of the waveguides and propagates electromagnetic waves of a desired wavelength. It has a cavity that forms an electrical short-circuit surface in a position where no reflection occurs .
[0011]
The waveguide plate according to the present invention has a single or a plurality of waveguides formed to transmit a high-frequency signal from the upper and lower surface directions to the horizontal direction using two conductor plates. Either one of the waveguides formed in the surface direction or the horizontal direction at the waveguide corner of the waveguide, or both of the waveguides from the corners to the outside, and communicates with the one or both of the waveguides. When an electromagnetic wave having a wavelength of 1 is propagated, a cavity for forming an electrical short-circuit surface at a position where no reflection occurs in the waveguide corner portion is provided.
[0012]
The high-frequency device according to the present invention includes means for transmitting or receiving a high-frequency signal such as a millimeter wave or a microwave that is input to or output from the waveguide plate. Is.
[0013]
DETAILED DESCRIPTION OF THE INVENTION
Embodiment 1 FIG.
FIG. 1 is a perspective view of a waveguide bend showing Embodiment 1 of the present invention. In the figure, the waveguide axes of the waveguide 1 and the waveguide 2 are orthogonal to each other, and one of the waveguides or both corners of the outer conductor wall end surfaces of the waveguides are extended at the two waveguide connection portions. Thus, the cavity 5 is formed. 2A to 2D are cross-sectional views of various forms in which a waveguide and a waveguide bend formed in the two metal plates 4a and 4b are cut at the center of the H plane by cutting or the like. 3A is a detailed cross-sectional view of FIG. 2, in which the waveguides 1 and 2 are formed on the metal plates 4a and 4b by cutting or the like. A cavity 5 formed by extending one or both corner outer conductor wall end faces 6 is formed. FIG. 3B shows the distribution of the electric field (standing wave) excited at the waveguide corner. Waveguides 1 and 2 in the figure show an example in which bending is formed at right angles (so that the tube axes are orthogonal).
[0014]
Next, the operation will be described. In general, a bent waveguide connection part is reflected due to the addition of series inductance and parallel capacitance that are mismatched to the impedance of the transmission system. As shown in the CC section of FIG. 3, the outer surface of the bent portion of the waveguide is formed with one or more step surfaces 3 having an appropriate dimension Lc with respect to the waveguide dimensions, and the conductor Reflection over a wide frequency range of transmission in the waveguide by changing the position of the wall (electrical short-circuited surface) and providing a series inductance and parallel capacitance that do not cause reflection to the transmission system impedance. It is possible to form a waveguide transmission system with low loss and little phase change.
[0015]
1 and 2 (a) to 2 (d), a cavity formed by extending one or both corner outer conductor wall end faces 6 of the waveguide at the connection portion between the waveguides 1 and 2. 5, 5a to 5d are provided, and the cavities 5 and 5a to 5d all play an equivalent role to the step surface.
That is, in FIG. 3B, electromagnetic waves such as microwaves and millimeter waves have a constant distribution (standing wave distribution) with a period of ½ of the wavelength in the waveguide in the transmission system. The end face 6 is used as a short-circuited face, and a virtual electrical short-circuited face is formed for each half of the in-tube wavelength in the cavity from this position.
[0016]
The cavity dimension (distance L from the inner wall end face of the waveguide 1 to the cavity conductor end face 6) in FIG. 3A is the short-circuit plane C-C (this virtual electric short-circuit plane formed by the above-described step plane). It is selected so as to be equivalent to a position protruding from the inner wall end face of the waveguide 1 by a distance Lc), and is shorter by a length corresponding to Lc from a length of ½ of the in-tube wavelength in the cavity. For this reason, the cavity 5 provides a series inductance equivalent to the step surface and a parallel capacitance at the waveguide bending portion, and the direction of the electromagnetic wave propagating from the waveguide 1 to the waveguide 2 is bent, and is not required within the desired signal band. Electromagnetic waves can be propagated smoothly without causing excessive reflection.
[0017]
As for the cavity size, L is the minimum length, but when L is added to an integral multiple of ½ of the guide wavelength, a short-circuit plane is formed in the same manner, so that substantially the same characteristics can be obtained.
Moreover, although the cavity shape has shown the example which forms the rectangular parallelepiped cavity 5 only in the metal plate 4a side in FIG. 3, as shown to 5a-5d of Fig.2 (a)-(d), a cavity shape is shown as follows. Any shape may be used as long as the virtual electrical short-circuit surface is selected to be equivalent to the CC portion in the figure.
[0018]
Furthermore, the figure shows a configuration using an E-plane waveguide bend, but even when an H-plane waveguide bend is configured, a cavity having a dimension that becomes a virtual electrical short-circuit plane is configured depending on the configuration. It is feasible.
[0019]
By adopting the waveguide bend configuration as described above, it is possible to suppress reflection over a wide frequency range to be transmitted as a waveguide mode, and to achieve a waveguide transmission system with low loss and little phase change. Can be formed.
[0020]
Further, since the waveguide bend does not have a minute and complicated structure like the step surface of the conventional waveguide bending portion, highly accurate cutting is not required.
[0021]
Furthermore, when the waveguide is formed by using the two metal plates 4a and 4b, all the waveguides formed on the metal plate have a punched structure, so that they can be manufactured by pressing or injection molding. A significant reduction in manufacturing costs can be expected.
[0022]
Embodiment 2. FIG.
FIG. 4 is a perspective view of a waveguide plate showing Embodiment 2 of the present invention. FIG. 5 is a cross-sectional view of the waveguide plate taken along the line DD in FIG. In the figure, waveguide plates 4a and 4b transmit in the horizontal direction the waveguides 1a and 1b that transmit high-frequency signals in each frequency band such as the microwave band and the millimeter wave band in the waveguide mode in the vertical direction. A plurality of waveguides 2 are provided. For example, the waveguide 2 is used as an interface for waveguide connection between the high-frequency device 10 having a plurality of waveguides and the planar antenna 11 in the same plane, and is provided on each plate. A high-frequency signal is transmitted between a plurality of opposing waveguides.
[0023]
In addition, although the example of a connection of a high frequency device and a planar antenna is shown in FIG. 5, it is used also as a waveguide connection structure used as a part of high frequency modules or a part of a high frequency module and a waveguide jig, etc. Is possible. At this time, the waveguide 1a and the waveguide 2 and the waveguide 1b and the waveguide 2 having different tube axis directions are connected to each other, and electromagnetic waves can be smoothly generated without causing unnecessary reflection within the desired signal band. In order to propagate, a tapered surface 7 and cavities 5a and 5b are provided on the outer inner surface of the bent portion.
[0024]
The cavities 5a and 5b have a short-circuited surface at the cavity end in the same manner as in the waveguide bends of FIGS. 1 to 3 shown in the first embodiment. Form a short-circuit plane.
The cavity dimensions are selected so that this virtual electrical short-circuit plane is equivalent to the step surface of the waveguide bend, and the series inductance and parallel capacitance equivalent to the step surface at the waveguide bend are determined by the cavity. Therefore, the direction of the electromagnetic wave propagating from the waveguide 1 to the waveguide 2 is bent, the reflection is suppressed over a wide frequency range transmitted as the waveguide mode, and the waveguide has low loss and little phase change. A tube transmission system can be formed.
[0025]
In addition, since a plurality of waveguide transmission systems are configured in the same plane, transmission lines can be processed and molded all at once, so that the manufacturing cost can be greatly reduced.
[0026]
Furthermore, the waveguide bend configuration using the above-mentioned cavity can greatly ease the requirements of machining accuracy, and a waveguide plate that obtains good electrical characteristics by an inexpensive processing method such as die casting or pressing. It is also possible to manufacture.
[0027]
Embodiment 3 FIG.
In the third embodiment of the present invention, a high-frequency device that transmits or receives high-frequency radio waves such as millimeter waves and microwaves that are input to or output from the waveguide plate of the second embodiment will be described. As this high-frequency device, for example, a millimeter-wave radar that transmits an RF signal in the millimeter wave band and receives a reflected wave from the surroundings to measure the distance and direction to an object existing in the surroundings, or a microwave communication signal A microwave communication device equipped with a transmitter to transmit or a receiver to receive a microwave communication signal, or a video of an object existing in the surroundings by scanning a transmission beam in the millimeter wave band and generating an image from the received wave There are millimeter wave imaging devices that obtain images.
[0028]
In the waveguide plate shown in FIG. 5, input / output terminals 1a, 1b, and 2 for inputting and outputting a high-frequency RF signal are connected to the planar antenna 11, the high-frequency device 10, and the like. In particular, in a frequency band where transmission loss is a problem, such as a millimeter wave band (30 GHz to 300 GHz), a waveguide plate having a plurality of waveguides as described above is reduced from a compact and integrated high-frequency package to a planar antenna. By using this as an external interface, it is possible to significantly reduce line loss compared to planar lines such as microstrip lines and triplate lines that are normally used as transmission lines in high-frequency packages. This greatly contributes to the increase in the number of transmission / reception channels and the diversification of the module structure.
In addition, since the demand for machining accuracy is relaxed, it is possible to configure a low-cost device as a whole high-frequency device compared to conventional machined products.
[0029]
【The invention's effect】
According to the present invention, in the waveguide corner portion that converts the propagation direction of the electromagnetic wave in the waveguide from the traveling direction to a different tube axis direction, from either one of the waveguides having different tube axis directions or both corners. An electrical short-circuit surface is provided in the waveguide corner and at a position where no reflection occurs when an electromagnetic wave having a desired wavelength is propagated while communicating with one or both of the waveguides toward the outside. By having a cavity to be formed, it is possible to obtain a waveguide bend that has low loss over a wide frequency range, good phase characteristics with little phase change, and can greatly reduce machining accuracy and manufacturing cost. it can.
[Brief description of the drawings]
FIG. 1 is a perspective view of a waveguide bend showing Embodiment 1 of the present invention.
FIG. 2 is a cross-sectional view of a waveguide bend showing Embodiment 1 of the present invention.
FIG. 3 is a detailed cross-sectional view of a waveguide bend and an electric field (standing wave) distribution at a corner portion according to Embodiment 1 of the present invention.
FIG. 4 is a perspective view of a waveguide plate showing Embodiment 2 of the present invention.
FIG. 5 is a perspective view of a waveguide plate showing Embodiment 2 of the present invention.
[Explanation of symbols]
1, 1a, 1b Waveguides traveling in the upper and lower direction,
2 Waveguides whose tube axes are orthogonal to the waveguides 1, 1a and 1b, 3 stepped step surfaces,
4a, 4b Metal plates for forming each waveguide,
5, 5a-5d cavity, 6 conductor wall end face of cavity 5, 7 taper surface,
10 Microwave and millimeter wave high frequency devices,
11 Planar antenna of microwave and millimeter wave band.

Claims

The propagation direction of the electromagnetic wave in the waveguide, the E-plane waveguide corners into a waveguide of the orthogonal direction from the traveling direction of the waveguide,
The outer wall surface of the waveguide in the traveling direction at the waveguide corner is equivalent,
An electromagnetic wave having a wavelength in the desired signal tube is located at a position parallel to the long side of the waveguide in the traveling direction from the approximate center of the waveguide corner to the outer wall surface of the waveguide in the orthogonal direction. In order to form a virtual electrical short circuit that does not reflect when propagating
It extends in a direction orthogonal to the outer wall surface of the waveguide in the traveling direction, is connected to the waveguide with the same width as the waveguide in the orthogonal direction, and is substantially half of the waveguide in the orthogonal direction. Formed by a waveguide having a height, and a conductor wall that short-circuits the waveguide provided at a position where the distance from the electrical short-circuit surface is ½ of a desired signal tube wavelength λ g ,
A waveguide bend characterized by having a cavity.

In the E- plane waveguide corner that converts the propagation direction of electromagnetic waves in the waveguide from the waveguide in the traveling direction to the waveguide in the orthogonal direction ,
The outer wall surface of the waveguide in the orthogonal direction at the waveguide corner is equivalently,
An electromagnetic wave having a wavelength in a desired signal tube is located at a position so as to be positioned on a plane parallel to the long side of the waveguide in the orthogonal direction from the approximate center of the waveguide corner to the outer wall surface of the waveguide in the traveling direction. In order to form a virtual electrical short circuit that does not reflect when propagating
It extends in a direction orthogonal to the outer wall surface of the waveguide in the orthogonal direction, is connected to the waveguide with the same width as the waveguide in the traveling direction, and is substantially half of the waveguide in the traveling direction. Formed by a waveguide having a height, and a conductor wall that short-circuits the waveguide provided at a position where the distance from the electrical short-circuit surface is ½ of a desired signal tube wavelength λ g ,
A waveguide bend characterized by having a cavity.

In the E- plane waveguide corner that converts the propagation direction of electromagnetic waves in the waveguide from the waveguide in the traveling direction to the waveguide in the orthogonal direction ,
A cavity projecting in a direction perpendicular to the outer wall surface of the waveguide in the traveling direction and provided to communicate with the waveguide with the same width as the waveguide in the orthogonal direction,
Reflection occurs when an electromagnetic wave having a desired signal tube wavelength is propagated from the approximate center of the waveguide corner portion to the outer wall surface of the waveguide in the orthogonal direction parallel to the long side of the waveguide in the traveling direction. Not to form a virtual electrical short circuit,
The distance from the electrical short-circuit plane parallel to the electrical short-circuit plane and from the electrical short-circuit plane toward the outer wall surface of the waveguide in the traveling direction is ½ of the desired signal tube wavelength λ g , And a first surface having a height equal to a distance from an outer wall surface of the waveguide in the orthogonal direction to a substantially center of the waveguide corner portion,
A second surface on the same plane as the outer wall surface of the waveguide in the orthogonal direction and orthogonal to the first surface;
And a third surface perpendicular to and in contact with the outer wall surface of the waveguide in the traveling direction,
A conductor wall surface having a rectangular parallelepiped shape configured with
A waveguide bend characterized by having a cavity .

In the E- plane waveguide corner that converts the propagation direction of electromagnetic waves in the waveguide from the waveguide in the traveling direction to the waveguide in the orthogonal direction ,
A cavity projecting in a direction perpendicular to the outer wall surface of the waveguide in the orthogonal direction and provided to communicate with the waveguide with the same width as the waveguide in the traveling direction,
Reflection occurs when an electromagnetic wave having a desired signal tube wavelength is propagated from the approximate center of the waveguide corner to the outer wall surface of the waveguide in the traveling direction in parallel with the long waveguide side in the orthogonal direction. Not to form a virtual electrical short circuit,
The distance from the electrical short-circuit plane parallel to the electrical short-circuit plane and from the electrical short-circuit plane toward the outer wall surface of the waveguide in the orthogonal direction is ½ of the desired signal tube wavelength λ g , And a first surface having a height equal to a distance from an outer wall surface of the waveguide in the traveling direction to a substantially center of the waveguide corner portion;
A second surface on the same plane as the outer wall surface of the waveguide in the traveling direction and perpendicular to the first surface;
And a third surface that is orthogonal to the outer wall surface of the waveguide in the orthogonal direction and is orthogonal to and in contact with the first surface;
A conductor wall surface having a rectangular parallelepiped shape configured with
A waveguide bend characterized by having a cavity .

In the E- plane waveguide corner that converts the propagation direction of electromagnetic waves in the waveguide from the waveguide in the traveling direction to the waveguide in the orthogonal direction ,
A cavity provided so as to project in a direction orthogonal to the outer wall surface of the waveguide in both the traveling direction and the orthogonal direction, and to communicate with each waveguide with the same width as each waveguide. ,
Reflection occurs when an electromagnetic wave having a desired signal tube wavelength is propagated from the approximate center of the waveguide corner portion to the outer wall surface of the waveguide in the orthogonal direction parallel to the long side of the waveguide in the traveling direction. A position where a virtual first electrical short-circuit surface is not formed and which extends from the substantial center of the waveguide corner portion to the outer wall surface of the waveguide in the traveling direction in parallel with the long side of the waveguide in the orthogonal direction In addition, in order to form a virtual second electrical short-circuit surface in which reflection does not occur when propagating an electromagnetic wave having a desired signal tube wavelength,
A distance parallel to the first electrical short-circuit surface and from the first electrical short-circuit surface toward the outer wall surface of the waveguide in the traveling direction is ½ of the desired signal tube wavelength λ g ; A first surface having a height equal to a distance from an outer wall surface of the waveguide in the orthogonal direction to a substantial center of the waveguide corner portion;
A distance parallel to the second electrical short-circuit surface and from the second electrical short-circuit surface toward the outer wall surface of the waveguide in the orthogonal direction is ½ of the desired signal tube wavelength λg, and A second surface having a height equal to the distance from the outer wall surface of the waveguide in the traveling direction to the approximate center of the waveguide corner portion;
A third surface perpendicular to and in contact with the first wall and perpendicular to the outer wall surface of the waveguide in the traveling direction;
And a fourth surface that is orthogonal to the outer wall surface of the waveguide in the orthogonal direction and is orthogonal to and in contact with the second surface;
A conductor wall surface having a rectangular parallelepiped shape or a cubic shape configured to include
A waveguide bend characterized by having a cavity .

Using two conductor plates, one or a plurality of waveguide grooves that transmit in the horizontal direction are formed in one conductor plate, and the conductor plate and the other conductor plate are formed from both ends of the waveguide groove. A waveguide that transmits in the direction of the upper and lower surfaces is formed, the two conductor plates are bonded to each other, waveguide ports at different positions on the upper and lower surfaces, and a high-frequency signal transmitted through the waveguide groove. In the tube plate
A waveguide plate comprising the cavity according to any one of claims 1 to 5 at a corner portion of an E- plane waveguide.

The waveguide plate according to claim 6 , wherein the waveguide plate is made by injection molding or press working.

A means for transmitting or receiving a high-frequency signal such as a millimeter wave or microwave input or output between the waveguide plates, wherein the waveguide plate according to claim 6 or 7 is mounted. A high-frequency device characterized by that.