JPH08330809A - Band pass filter - Google Patents

Band pass filter

Info

Publication number
JPH08330809A
JPH08330809A JP15270395A JP15270395A JPH08330809A JP H08330809 A JPH08330809 A JP H08330809A JP 15270395 A JP15270395 A JP 15270395A JP 15270395 A JP15270395 A JP 15270395A JP H08330809 A JPH08330809 A JP H08330809A
Authority
JP
Japan
Prior art keywords
mode
resonator
resonators
pass filter
side walls
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
Application number
JP15270395A
Other languages
Japanese (ja)
Other versions
JP2596401B2 (en
Inventor
Hisashi Sujikai
久 筋誡
Kazuo Haginuma
一夫 萩沼
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
NEC Corp
Original Assignee
NEC Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by NEC Corp filed Critical NEC Corp
Priority to JP15270395A priority Critical patent/JP2596401B2/en
Publication of JPH08330809A publication Critical patent/JPH08330809A/en
Application granted granted Critical
Publication of JP2596401B2 publication Critical patent/JP2596401B2/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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Abstract

PURPOSE: To provide the band pass filter of high capacity and a low loss, which suppresses an unnecessary TE mode. CONSTITUTION: In the band pass filter where input/output waveguides 15 and 16 are connected with the plural square cavity resonators 11-14 of a TE103 mode through connection holes 17 provided at the center of partition walls 18, adjacent resonators 12 and 13 are arranged so that side walls become common, the side walls are set to be mutual partition walls 19 and a connection hole 20 is provided in the center of the side walls so as to connect them. The magnetic field of TE10n (n = even), which is generated in the resonator 12 of an input-side, operates in such a way that the magnetic fields are excited in the resonators 13 of an output-side. Since the connection hole 20 is parallel to the direction of the magnetic fields, the phases of the magnetic fields appear as opposite. Thus, they compensate each other, and they are not excited in the resonators 13 of the output-side.

Description

【発明の詳細な説明】Detailed Description of the Invention

【0001】[0001]

【産業上の利用分野】本発明はマイクロ波通信装置に使
用される立体回路に関し、特にマイクロ波帯のTE103
モード帯域通過濾波器の不要モードを抑制する構造に関
する。
BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a three-dimensional circuit used in a microwave communication device, and more particularly to a microwave-type TE 103.
The present invention relates to a structure for suppressing unnecessary modes in a mode bandpass filter.

【0002】[0002]

【従来の技術】マイクロ波帯分波装置等に使用されるT
103モード導波管型帯域通過濾波器においては、使用
するモード以外の不要モードの共振による帯域特性劣化
を考慮することが必要である。
2. Description of the Related Art T used in microwave band splitters and the like
In the E 103 mode waveguide band pass filter, it is necessary to consider the band characteristic deterioration due to the resonance of unnecessary modes other than the mode to be used.

【0003】TEomnモード方形導波管を有する導波管
型帯域濾波器においては、容量を高くして低損失にする
ため、TE103モード方形導波管共振器がよく使用され
る。TE103モード方形導波管共振器内部において、T
103モード共振を発生させ、それらを順次結合してゆ
くことによって、濾波器を構成する。一方、共振器内部
には同時にn=3以外のTE10nモードも存在し、順次
結合して、出力端子に伝達される。
In a waveguide bandpass filter having a TE omn mode rectangular waveguide, a TE 103 mode rectangular waveguide resonator is often used because of its high capacitance and low loss. In the TE 103 mode rectangular waveguide resonator, T
A filter is constructed by generating E103 mode resonances and sequentially coupling them. On the other hand, TE 10n modes other than n = 3 also exist inside the resonator at the same time, and are sequentially coupled and transmitted to the output terminal.

【0004】従来のTE103モード方形導波管共振器を
用いた帯域濾波器の構造は、図4に示すようなものであ
る。図4において1〜4はTE103モード方形導波管共
振器、5は入力導波管、6は出力導波管であり、これら
は入力側から出力側に向けて直線的に連結され、各隔壁
7、7の中央部分に形成された結合孔8、8で相互に結
合されている。調整ネジ9、9は、各共振器1〜4の共
振周波数及び結合量を微調整するためのものである。
[0004] structure of a conventional bandpass filter using the TE 103 mode rectangular waveguide resonator is as shown in FIG. In FIG. 4, 1 to 4 are TE 103 mode rectangular waveguide resonators, 5 is an input waveguide, and 6 is an output waveguide, which are linearly connected from the input side to the output side. The partition walls 7 and 7 are coupled to each other by coupling holes 8 and 8 formed in the central portions of the partitions. The adjusting screws 9 and 9 are for finely adjusting the resonance frequency and the coupling amount of each of the resonators 1 to 4.

【0005】このような帯域濾波器における各共振器の
結合部における磁界分布を図5に示す。共振器2内に励
起されたTEモードの磁界は、隔壁7の中央部分に設け
た結合孔8を介して、それと隣接する共振器3内に、図
に示すように磁界を励起させる。その結果、図4に示し
た帯域通過濾波器は、各共振器間で所望のTE103モー
ド以外のTE10nモード(n=1, 2,... : n≠3)の結合も
生じるため、減衰特性は第6図に示すようなものにな
る。
FIG. 5 shows a magnetic field distribution at a coupling portion of each resonator in such a bandpass filter. The TE-mode magnetic field excited in the resonator 2 excites the magnetic field in the adjacent resonator 3 through the coupling hole 8 provided in the central portion of the partition wall 7 as shown in the figure. As a result, the band-pass filter shown in FIG. 4 also causes coupling of TE 10n modes (n = 1, 2,...: N ≠ 3) other than the desired TE 103 mode between the resonators. The attenuation characteristics are as shown in FIG.

【0006】[0006]

【発明が解決しようとする課題】このように従来のTE
103モード方形導波管共振器を用いた帯域濾波器は、容
量が高く低損失であるという長所がある一方で、図6に
示すようなTE10n(n≠3)の不要モード共振が生じる
という欠点があった。
As described above, the conventional TE
A bandpass filter using a 103- mode rectangular waveguide resonator has the advantage of high capacity and low loss, but also generates unwanted mode resonance of TE 10n (n ≠ 3) as shown in FIG. There were drawbacks.

【0007】また、円形TEomnモード帯域通過濾波器
の不要モードを抑制する方法としては、結合部付近に設
けた結合調整ネジをバランス良く調整することにより、
不要共振モードを抑制するもの(特開昭62−5530
号公報)や、一部の共振器の空胴部直径を他の空胴部直
径と異ならせることにより、不要共振モードの基本共振
モードへの接近を抑え帯域特性劣化を改善するもの(特
開昭58−187001号)がある。
As a method of suppressing unnecessary modes of the circular TE omn mode band-pass filter, a coupling adjusting screw provided near the coupling portion is adjusted in a well-balanced manner.
A device that suppresses an unnecessary resonance mode (Japanese Unexamined Patent Publication No.
Japanese Patent Application Laid-Open No. H11-15095) and a method in which the cavity diameter of some of the resonators is made different from the diameter of the other cavity, thereby suppressing the unnecessary resonance mode from approaching the basic resonance mode and improving the band characteristic deterioration (Japanese Patent Application Laid-Open (JP-A) no. 58-187001).

【0008】しかしながら、これらは円形TEomnモー
ド帯域通過濾波器におけるものであって、それとは磁界
分布が異なる方形TEomnモード帯域通過濾波器に応用
することができず、方形TEomnモード帯域通過濾波器
においては、不要共振モードの抑制が十分に図られてい
なかった。
However, these are those in the circular TE OMN mode band-pass filter, can not field distribution is applied to different rectangular TE OMN mode band-pass filter to that, rectangular TE OMN mode band-pass filter In such a case, the suppression of the unnecessary resonance mode was not sufficiently achieved.

【0009】本発明は、方形TE103モード導波管共振
器を有する帯域通過濾波器において、不要モード共振の
うち、TE10n(n=偶数)モード共振を抑制すること
ができる帯域通過濾波器の提供を目的とする。
The present invention is directed to a band-pass filter having a rectangular TE 103 mode waveguide resonator, which is capable of suppressing TE 10n (n = even number) mode resonance among unnecessary mode resonances. For the purpose of providing.

【0010】[0010]

【課題を解決するための手段】上記目的を達成するため
本発明は、入出力導波管と、複数個のTE103モードの
方形導波管空胴共振器を、それらの隔壁の中央部に設け
られた結合孔を介して結合させた帯域通過濾波器におい
て、隣接する何れかの前記方形導波管空胴共振器同士を
側壁が共通になるように配置して該側壁を相互の隔壁と
なし、該側壁の中央に結合孔を設けて相互に結合する構
成としてある。
In order to achieve the above object, the present invention provides an input / output waveguide and a plurality of TE 103 mode rectangular waveguide cavity resonators in the central portions of their partitions. In a bandpass filter coupled through a provided coupling hole, any one of the adjacent rectangular waveguide cavity resonators is arranged so that the sidewalls are common, and the sidewalls are mutually partition walls. None, a coupling hole is provided in the center of the side wall to couple them to each other.

【0011】また本発明は、前記方形導波管空胴共振器
がn個(nは、偶数)の場合に、端からn/2番目の前
記方形導波管空胴共振器同士を側壁が共通になるように
配置して該側壁を相互の隔壁となし、該側壁の中央に結
合孔を設けて相互に結合する構成としてある。
Further, according to the present invention, when the number of the rectangular waveguide cavity resonators is n (n is an even number), the side walls form the n / 2-th rectangular waveguide cavity resonators from the end. The sidewalls are arranged so as to be common to each other and serve as partitions, and a coupling hole is provided at the center of the sidewall to be coupled to each other.

【0012】[0012]

【作用】側壁を隔壁として結合された共振器の該結合部
において、入力側の共振器内で発生するTE10n(n=
偶数)の結合部付近の磁界分布は、図2のようになる。
すなわち、入力側の共振器内で発生するTE10n(n=
偶数)の磁界は、出力側の共振器内にそれぞれ磁界を励
起させるように作用するが、その結合孔が電界方向と平
行の平面上に設けられているため、これら磁界は相互に
位相が逆となって表われ、その結果互いに打ち消し合
い、TE10n(n=偶数)モードは、出力側の共振器内
に励起されなくなる。
In the coupled portion of the resonator coupled with the side wall as the partition wall, TE 10n (n = n
The magnetic field distribution near the (even) coupling portion is as shown in FIG.
That is, TE 10n generated in the resonator on the input side (n =
(Even number) magnetic field acts to excite each magnetic field in the resonator on the output side, but since the coupling holes are provided on the plane parallel to the electric field direction, these magnetic fields have mutually opposite phases. As a result, they cancel each other out, and the TE 10n (n = even) mode is no longer excited in the resonator on the output side.

【0013】[0013]

【実施例】以下、本発明の一実施例について図面を参照
して説明する。第1図は本発明に基づいて構成された帯
域通過濾波器の一実施例を示す側面図である。実施例に
おいて帯域通過濾波器は、図4に示した従来のものと同
様に、4つのTE103モード方形導波管共振器(以下、
共振器)11、12、13、14、入力導波管15及び
出力導波管16を入力側から出力側に結合させて構成さ
れるものである。ここで、入力導波管15と共振器1
1、共振器11と共振器12、共振器13と共振器1
4、及び共振器14と出力導波管16は、従来と同様
に、直線的に配置、連結され、各隔壁17の中央に設け
た結合孔18を介して相互に結合されている。
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a side view showing an embodiment of a bandpass filter constructed according to the present invention. In the embodiment, the band-pass filter is composed of four TE 103 mode rectangular waveguide resonators (hereinafter, referred to as the conventional one shown in FIG. 4).
The resonators 11, 12, 13, and 14, the input waveguide 15 and the output waveguide 16 are coupled from the input side to the output side. Here, the input waveguide 15 and the resonator 1
1, resonator 11 and resonator 12, resonator 13 and resonator 1
4, the resonator 14 and the output waveguide 16 are linearly arranged and connected in the same manner as in the related art, and are mutually connected via a coupling hole 18 provided at the center of each partition 17.

【0014】一方、共振器12と共振器13は、並列に
配置され、その側壁を相互の隔壁19として物理的に連
結されている。そしてこの隔壁19の中央に設けた結合
孔20を介して相互に電磁気的に結合されている。すな
わち、共振器12と共振器13とを結合する結合孔20
は、共振器12内に励起される電界方向と平行の平面上
に形成されることとなる。
On the other hand, the resonator 12 and the resonator 13 are arranged in parallel, and their side walls are physically connected to each other as partition walls 19. Then, they are electromagnetically coupled to each other through a coupling hole 20 provided at the center of the partition wall 19. That is, the coupling hole 20 for coupling the resonator 12 and the resonator 13
Are formed on a plane parallel to the direction of the electric field excited in the resonator 12.

【0015】なお、各共振器11〜14、入出力導波管
15、16及びこれらの結合孔18、20には、調整ネ
ジ21が設けられ、各共振器11〜14の共振周波数及
び結合量を微調整する。
An adjusting screw 21 is provided in each of the resonators 11 to 14, the input / output waveguides 15 and 16 and the coupling holes 18 and 20, and the resonance frequency and the coupling amount of each of the resonators 11 to 14 are set. Fine-tune.

【0016】次に、本帯域通過導波管の動作について説
明する。図1において、入力導波管15に入力された電
磁波は、結合孔17を介して共振器11、共振器12へ
と結合し伝搬する。この場合の磁界分布は、図5に示し
た従来のものと同様である。
Next, the operation of the bandpass waveguide will be described. In FIG. 1, the electromagnetic wave input to the input waveguide 15 is coupled to the resonators 11 and 12 via the coupling holes 17 and propagates. The magnetic field distribution in this case is similar to the conventional one shown in FIG.

【0017】しかしながら、共振器12と共振器13と
のTE10n(n=偶数)の場合の結合部付近の磁界分布
は図2のようになる。すなわち、共振器12と共振器1
3との結合は、電界方向と平行の平面となる隔壁19に
設けられた結合孔20によって行われるが、出力側の共
振器13の結合部付近で発生する磁界は、共振器12内
の磁界30によって励起された磁界32と、共振器12
内の磁界31によって励起された磁界33であり、それ
らは図2に示すように位相が互いに逆相になる。これに
より、磁界32と磁界33とは互いに相殺され、TE
10n(n=偶数)モードは共振器13に励起されなくな
り、出力側に伝達されない。そして、共振器13に励起
されたTEモードだけが、共振器14、出力導波管16
へと伝搬する。
However, the magnetic field distribution near the coupling portion in the case of TE 10n (n = even number) between the resonators 12 and 13 is as shown in FIG. That is, the resonator 12 and the resonator 1
3 is formed by a coupling hole 20 provided in a partition wall 19 which is a plane parallel to the direction of the electric field. The magnetic field generated near the coupling portion of the resonator 13 on the output side is the magnetic field in the resonator 12. The magnetic field 32 excited by 30 and the resonator 12
The magnetic field 33 is excited by the magnetic field 31 in the inside, and these phases are opposite to each other as shown in FIG. As a result, the magnetic field 32 and the magnetic field 33 cancel each other out, and TE
The 10n (n = even) mode is not excited by the resonator 13 and is not transmitted to the output side. Then, only the TE mode excited in the resonator 13 is generated by the resonator 14 and the output waveguide 16
Propagate to.

【0018】この結果、図1の構造を有する帯域通過濾
波器の減衰特性は、図3に示すようなものとなり、全体
として、不要なTE10n(n=偶数)モードの共振を抑
制することができる。
As a result, the attenuation characteristic of the band-pass filter having the structure shown in FIG. 1 is as shown in FIG. 3, and the unnecessary TE 10n (n = even number) mode resonance can be suppressed as a whole. it can.

【0019】なお、上記実施例では、n個の共振器のう
ち、端からn/2番目のものの側壁が共通になるように
配置し、結合したが、何れの位置における隣り合う共振
器同士を結合しても同様の効果が得られる。
In the above embodiment, among the n resonators, the side walls of the n / 2th resonator from the end are arranged and connected in common, but at any position, adjacent resonators may be connected to each other. Similar effects can be obtained by combining them.

【0020】[0020]

【発明の効果】以上説明したように本発明によれば、隣
接する何れかの方形導波管空胴共振器同士を側壁が共通
になるように配置して該側壁を相互の隔壁となし、該側
壁の中央に結合孔を設けて相互に結合することにより、
該結合孔を通して結合される際にTE10nモードのう
ち、n=偶数のものについて相殺が起こり、不要TEモ
ードを抑制することができるようになる。したがって、
高容量、低損失の帯域通過濾波器を実現することができ
る。
As described above, according to the present invention, any adjacent rectangular waveguide cavity resonators are arranged so that their side walls are common to each other, and the side walls serve as mutual barriers. By forming a coupling hole in the center of the side wall and coupling them to each other,
At the time of coupling through the coupling holes, n = even ones of the TE 10n modes cancel each other, so that unnecessary TE modes can be suppressed. Therefore,
A high-capacity, low-loss bandpass filter can be realized.

【図面の簡単な説明】[Brief description of drawings]

【図1】本発明帯域通過濾波器の一実施例を示す側面図
である。
FIG. 1 is a side view showing an embodiment of a bandpass filter of the present invention.

【図2】本発明の作用を説明する図1の結合部における
の磁界分布を示す図である。
FIG. 2 is a diagram illustrating the magnetic field distribution in the coupling portion of FIG. 1 for explaining the operation of the present invention.

【図3】本発明による帯域通過濾波器の減衰特性を示す
図である。
FIG. 3 is a diagram showing an attenuation characteristic of a bandpass filter according to the present invention.

【図4】従来の帯域通過濾波器の一例を示す側面図であ
る。
FIG. 4 is a side view showing an example of a conventional band-pass filter.

【図5】従来の帯域通過濾波器の結合部における磁界分
布を示す図である。
FIG. 5 is a diagram showing a magnetic field distribution at a coupling portion of a conventional band-pass filter.

【図6】従来の帯域通過濾波器の減衰特性を示す図であ
る。
FIG. 6 is a diagram showing an attenuation characteristic of a conventional bandpass filter.

【符号の説明】[Explanation of symbols]

11〜14 TE103モード方形導波管共振器 15 入力導波管 16 出力導波管 17、19 隔壁 18、20 結合孔 21 調整ネジ 30〜33 結合部におけるTE10n(n=偶数)モー
ドの磁界
11 to 14 TE 103 mode rectangular waveguide resonator 15 input waveguide 16 output waveguide 17, 19 partition wall 18, 20 coupling hole 21 adjusting screw 30 to 33 TE 10n at the junction (n = even number) mode magnetic field

Claims (2)

【特許請求の範囲】[Claims] 【請求項1】 入出力導波管と、複数個のTE103モー
ドの方形導波管空胴共振器を、それらの隔壁の中央部に
設けられた結合孔を介して結合させた帯域通過濾波器に
おいて、 隣接する何れかの前記方形導波管空胴共振器同士を側壁
が共通になるように配置して該側壁を相互の隔壁とな
し、該側壁の中央に結合孔を設けて相互に結合すること
を特徴とする帯域通過濾波器。
1. A band-pass filter in which an input / output waveguide and a plurality of TE 103 mode rectangular waveguide cavities are coupled through a coupling hole provided at the center of the partition wall. In the device, any one of the adjacent rectangular waveguide cavity resonators is arranged such that the side walls are common, and the side walls are formed as mutual partition walls. A bandpass filter characterized by combining.
【請求項2】 前記方形導波管空胴共振器がn個(n
は、偶数)の場合に、端からn/2番目の前記方形導波
管空胴共振器同士を側壁が共通になるように配置して該
側壁を相互の隔壁となし、該側壁の中央に結合孔を設け
て相互に結合することを特徴とする請求項1記載の帯域
通過濾波器。
2. The number of the rectangular waveguide cavity resonators is n (n
In the case of (even number), the n / 2-th rectangular waveguide cavity resonators from the end are arranged so that the side walls are common, and the side walls are formed as mutual partition walls. 2. The band-pass filter according to claim 1, wherein a coupling hole is provided and coupled to each other.
JP15270395A 1995-05-26 1995-05-26 Bandpass filter Expired - Lifetime JP2596401B2 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
JP15270395A JP2596401B2 (en) 1995-05-26 1995-05-26 Bandpass filter

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
JP15270395A JP2596401B2 (en) 1995-05-26 1995-05-26 Bandpass filter

Publications (2)

Publication Number Publication Date
JPH08330809A true JPH08330809A (en) 1996-12-13
JP2596401B2 JP2596401B2 (en) 1997-04-02

Family

ID=15546306

Family Applications (1)

Application Number Title Priority Date Filing Date
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Country Status (1)

Country Link
JP (1) JP2596401B2 (en)

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009194624A (en) * 2008-02-14 2009-08-27 Nec Corp Band-pass filter, manufacturing method of the filter, and conductor plate used for the filter
WO2009133713A1 (en) * 2008-05-01 2009-11-05 パナソニック株式会社 High-frequency filter device
JP2013106114A (en) * 2011-11-11 2013-05-30 Japan Radio Co Ltd Waveguide band-pass filter
JP2022518379A (en) * 2019-01-08 2022-03-15 ケーエムダブリュ・インコーポレーテッド Waveguide filter
US11955680B2 (en) 2019-01-08 2024-04-09 Kmw Inc. Waveguide filter

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2009194624A (en) * 2008-02-14 2009-08-27 Nec Corp Band-pass filter, manufacturing method of the filter, and conductor plate used for the filter
WO2009133713A1 (en) * 2008-05-01 2009-11-05 パナソニック株式会社 High-frequency filter device
JP2013106114A (en) * 2011-11-11 2013-05-30 Japan Radio Co Ltd Waveguide band-pass filter
JP2022518379A (en) * 2019-01-08 2022-03-15 ケーエムダブリュ・インコーポレーテッド Waveguide filter
US11955680B2 (en) 2019-01-08 2024-04-09 Kmw Inc. Waveguide filter

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