JPS58103202A - Dielectric filter - Google Patents
Dielectric filterInfo
- Publication number
- JPS58103202A JPS58103202A JP20146381A JP20146381A JPS58103202A JP S58103202 A JPS58103202 A JP S58103202A JP 20146381 A JP20146381 A JP 20146381A JP 20146381 A JP20146381 A JP 20146381A JP S58103202 A JPS58103202 A JP S58103202A
- Authority
- JP
- Japan
- Prior art keywords
- conductors
- conductor
- dielectric
- filter
- plate
- 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
- H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
- H01P1/00—Auxiliary devices
- H01P1/20—Frequency-selective devices, e.g. filters
- H01P1/201—Filters for transverse electromagnetic waves
- H01P1/205—Comb or interdigital filters; Cascaded coaxial cavities
Landscapes
- Physics & Mathematics (AREA)
- Electromagnetism (AREA)
- Control Of Motors That Do Not Use Commutators (AREA)
Abstract
Description
【発明の詳細な説明】
（１）発明の技術分野
本発明はマイクロ波帯に用いられる誘電体フィルタに関
するものである。DETAILED DESCRIPTION OF THE INVENTION (1) Technical Field of the Invention The present invention relates to a dielectric filter used in the microwave band.
（２）技術の背景
マイクロ波無線装置等に使用される誘電体フィルタとし
て外導体となる筐体内に納められた誘電体内にフィルタ
特性に対応′した所定の間隔で共振用導体（内導体）を
配置した同軸型フィルタは公知である。このような同軸
型フィルタは車載、や携帯等の移動無線装置に使用する
には大型で重く。(2) Background of the technology As a dielectric filter used in microwave radio equipment, etc., resonant conductors (inner conductors) are placed at predetermined intervals corresponding to the filter characteristics within a dielectric body that is housed in a housing and serves as an outer conductor. The arranged coaxial filter is well known. Such coaxial filters are too large and heavy to be used in mobile radio devices such as vehicles and portable devices.
また焼結体である誘電体に高精度で内導体用の孔加工を
しなければならず製造が容易ではない。このような点を
改良するため誘電体表面に複数の共振用導体を設は孔加
工を不要としたマイクロストリップライン型フィルタが
開発されている。このようなマイクロストリップライン
型フィルタにおいてもさらに々おその小型、軽量化が要
望されている。In addition, holes for the inner conductor must be formed with high precision in the dielectric material, which is a sintered body, which is not easy to manufacture. In order to improve this point, a microstrip line type filter has been developed in which a plurality of resonant conductors are provided on the dielectric surface, eliminating the need for hole processing. There is also a demand for such microstripline filters to be even smaller and lighter.
（３）従来技術と問題点
第１図に従来のマイクロストリップライン型の四分の一
波長誘電体フィルタを２段で構成した場合の例を示す。(3) Prior Art and Problems FIG. 1 shows an example of a conventional microstrip line type quarter-wavelength dielectric filter configured in two stages.
誘電体板ｌの表面に２本の共振用導体３および入出力用
結合線路４が設けられる。Two resonance conductors 3 and an input/output coupling line 4 are provided on the surface of the dielectric plate l.
誘電体板１の薬面および下面はアース用導体２で覆われ
る。各共振用導体３は共振波長の四分の一波長の奇数倍
で共振する長さに形成される。各共振用導体３の下端部
はアース用導体２へ短絡し。The top and bottom surfaces of the dielectric plate 1 are covered with a grounding conductor 2. Each resonant conductor 3 is formed to have a length that resonates at an odd multiple of a quarter wavelength of the resonant wavelength. The lower end of each resonance conductor 3 is short-circuited to the ground conductor 2.
上端は開放端部である。このような誘電体フィルタにお
いては、要求されるフィルタ特性に応じて両共振用導体
３間の距離が定まり、従って各共振用導体３Ｖｉこの形
状の１までは相互に近づけることはできず各共振用導体
間の空間が一デッドスペースとなって誘電体フィルタ全
体の容積をこれ以上小さくすることはできない。The top end is an open end. In such a dielectric filter, the distance between both resonance conductors 3 is determined depending on the required filter characteristics, and therefore each resonance conductor 3Vi of this shape cannot be brought close to each other, and each resonance conductor 3Vi has this shape. The space between the conductors becomes a dead space, making it impossible to further reduce the overall volume of the dielectric filter.
（４）発明の目的
本発明は上記の点に鑑みなされたものであって、共振用
導体の形状を変えることによ、って要求されるフィルタ
特性を保持したまま共振用導体同士を近づけ鹸電体表面
上のデッドスペースを減少可能としこれによって誘電体
フィルタの形状を小型化することを目的とする。(4) Purpose of the Invention The present invention has been made in view of the above-mentioned points. By changing the shape of the resonant conductors, the resonant conductors can be brought closer to each other while maintaining the required filter characteristics. It is an object of the present invention to reduce the dead space on the surface of an electric body, thereby reducing the size of a dielectric filter.
（５）発明の構成
この目的を達成するため本発明に係る誘電体フィルタは
誘電体板の一表面上に複数の並列配着した共振用導体お
よび入出力用結合線路を有し。(5) Structure of the Invention In order to achieve this object, the dielectric filter according to the present invention has a plurality of resonance conductors and input/output coupling lines arranged in parallel on one surface of a dielectric plate.
その反対表面上をアース用導体で覆い、上記各共振用導
体の一端を上記アース用導体に接続する短絡端部とし、
他端を開放端部とした誘電体フィルタにおいて、上記共
振用導体の形状をその開放端部が短絡端部方向に折返さ
れて屈曲した形状としている。The opposite surface is covered with a grounding conductor, and one end of each of the resonance conductors is used as a short-circuit end connected to the grounding conductor,
In the dielectric filter with the other end being an open end, the resonance conductor has a shape in which the open end is folded back and bent in the direction of the short-circuited end.
（６） 発明の実施例
第２図は本発明に係る四分の一波長銹電体フィルタの斜
視図であ・る。誘電体板１１の表面上に４２つの共振用
導体１３および２つの入出力用結合線路１４．１４が設
けられる。誘電体板１１の裏面および下面はアース用導
体１２で覆われる。共振用導体１３の開放端部は下端の
アース用導体との短絡端部方向に折曲されて屈曲した形
状である。(6) Embodiment of the Invention FIG. 2 is a perspective view of a quarter-wavelength electric filter according to the present invention. On the surface of the dielectric plate 11, 42 resonance conductors 13 and two input/output coupling lines 14, 14 are provided. The back and lower surfaces of the dielectric plate 11 are covered with a grounding conductor 12. The open end of the resonance conductor 13 is bent in the direction of the short-circuited end with the grounding conductor at the lower end.
四分の一旦共振用導体においては短絡端部で磁界が最大
となり、開放端部で電界が最大となる。In a quarter-resonant conductor, the magnetic field is maximum at the shorted end, and the electric field is maximum at the open end.
図の左側の入出力用結合線路１４は先端が短絡されてい
るため主に磁界に基〈共振用導体との電磁的結合（カッ
プリング）により外部配線とフィルタとのインピダンス
特性を整合させるような位置。The input/output coupling line 14 on the left side of the figure is short-circuited at the tip, so it is mainly based on the magnetic field. position.
形状に配設される。一方、右側の入出力用端子１４１は
共振用導体１３の開放端部に近接するため主に電界に基
く共振用導体との電磁的結合により外部配線とフィルタ
とのインビダンス特性を整合させるよう々位置、形状に
配設される。フィルタの通過周波数帯域のロスを少くし
特性を向上させるために共振用導体１３は高周波電流が
十分流れるような厚さをもたせることが望ましい。この
ため、誘電体板上に一旦共振用導体の形状の導体パター
ンを密着形成しこの導体パターン上にこれと同形状の金
属板をハンダ接合あるいは導電性ペースト等により接着
して共振用導体１３を形成することが望ましい。導体パ
ターンを形成するには誘電体板を無電解メッキ処理後所
望形状にエツチングを行う方法あるいは所望形状の導体
パターンを誘電体板上にそ着させて形成することができ
る。arranged in a shape. On the other hand, since the input/output terminal 141 on the right side is close to the open end of the resonance conductor 13, the impedance characteristics of the external wiring and the filter are matched mainly through electromagnetic coupling with the resonance conductor based on the electric field. Arranged in position and shape. In order to reduce the loss in the pass frequency band of the filter and improve the characteristics, it is desirable that the resonant conductor 13 has a thickness that allows a sufficient high frequency current to flow therethrough. For this purpose, a conductor pattern in the shape of a resonant conductor is first closely formed on a dielectric plate, and a metal plate having the same shape is bonded onto this conductor pattern by soldering or conductive paste to form the resonant conductor 13. It is desirable to form. The conductor pattern can be formed by etching the dielectric plate into a desired shape after electroless plating, or by depositing a conductor pattern in the desired shape on the dielectric plate.
第３図に本発明の別の実施例を示す。この例においては
、共振用導体１３を形成し念誘電体板１１の表面を別の
誘電体板口」で覆っている。この別の誘電体板１１ｍの
外表面はアース用導体１２ｍで覆われ、各誘電体板１１
．１１ｍのアース用導体１２．１２ａ同士は電気的に接
続される。この別の誘電体板目」は誘電体板１１の共振
用導体１３と同一形状の共振用導体をこれと対向してそ
の表面上に形成してもよいし、又はこのような共振用導
体を具備しないものであってもよい。FIG. 3 shows another embodiment of the invention. In this example, a resonance conductor 13 is formed and the surface of the dielectric plate 11 is covered with another dielectric plate opening. The outer surface of this other dielectric plate 11m is covered with a grounding conductor 12m, and each dielectric plate 11
．． The 11 m long grounding conductors 12.12a are electrically connected to each other. This other dielectric plate may be formed by forming a resonant conductor having the same shape as the resonant conductor 13 of the dielectric plate 11 on its surface opposite to the resonant conductor 13, or by forming such a resonant conductor on its surface. It may not be provided.
（７）発明の詳細
な説明したように１本発明に係る誘電体フィルタにおい
ては、開放端部を短絡端部方向に屈曲させた形状の共振
用導体を並列して誘電体板表面上に形成している。即ち
、隣接する共振用導体の開放端部と短絡端部とが接近し
て配置され磁界の強い部分と電界の強い部分とが接近す
る。従って、第１図に示した真直形状の共振用導体に比
べ共振用導体同士のカップルが弱くなり＠１図のものと
同一のフィルタ特性を得ようとすれば共振用導体同土間
距離を近づけなければならない。このため共振用導体間
のデッドスペースが減少し、また共振用導体の高さが低
くなるため誘電体板の形状を小さくすることができ誘電
体フィルタの小型＠線化が達成される。実験例を示せば
、共振用導体の長さ１９ｍ、厚さ０．８鰭、−電体板寸
法２Ｘ３Ｘ３．５ｍ＋、フイに夕体積約２．６ＣＣの第
１図に示す従来形状の誘電体フィルタと同じ伝送特性の
本発明に係る誘電体フィルタにおいては、共振用導体の
長さ１９ｍｍ、厚さ０．８ｍｓ、誘電体板寸法１、Ｉ
Ｘ ３．Ｉ Ｘ ３．５胴、フィルタ体積的１．４ ｃ
ｃであった。(7) As described in detail of the invention, in the dielectric filter according to the present invention, resonant conductors each having an open end bent toward a short-circuited end are formed in parallel on the surface of a dielectric plate. are doing. That is, the open ends and short-circuited ends of adjacent resonant conductors are arranged close to each other, and the portions where the magnetic field is strong and the portions where the electric field is strong are close to each other. Therefore, the coupling between the resonant conductors is weaker than with the straight resonant conductors shown in Figure 1, and in order to obtain the same filter characteristics as in Figure 1, the distance between the resonant conductors and the ground must be made closer. Must be. Therefore, the dead space between the resonant conductors is reduced, and the height of the resonant conductors is lowered, so that the shape of the dielectric plate can be made smaller, and the dielectric filter can be made smaller and more compact. To give an example of an experiment, a dielectric filter of the conventional shape shown in Fig. 1 has a resonant conductor length of 19 m, a fin thickness of 0.8 m, an electric board size of 2 x 3 x 3.5 m +, and a fin volume of about 2.6 cc. In the dielectric filter according to the present invention having the same transmission characteristics, the length of the resonance conductor is 19 mm, the thickness is 0.8 ms, the dielectric plate size is 1,
X 3. I x 3.5 cylinder, filter volume 1.4 c
It was c.
本発明に係る誘電体フィルタにおいて誘電体板上に一旦
薄膜導体パｒ−ンをメッキあるいは印刷等により密着し
て形成しこの上に金属板を重ねることにより共振用導体
を形成すればフィルタ通過帯域での伝送ロスの少い誘電
体フィルタが得られる。In the dielectric filter according to the present invention, once a thin film conductor pattern is formed on the dielectric plate by plating or printing, and a resonant conductor is formed by overlaying a metal plate on top of the thin film conductor pattern, the filter pass band is A dielectric filter with low transmission loss can be obtained.
本発明に係る誘電体フィルタにおいて、誘電体夕通過帯
域以外の周波数の減衰特性を向上させることができる。In the dielectric filter according to the present invention, it is possible to improve the attenuation characteristics of frequencies other than the dielectric passband.
第１図は従来の誘電体フィルタの斜視図、第２図および
第３図は各々本発明に係る誘電体フィルタの各別の例を
示す斜視図である。
１１・・・誘電体板、１２・・・アース用導体、１３・
・・共振用導体、 １４．１４’・・・入出力用結合線
路。
特許出願人
富士通株式会社
特許出願代理人
弁理士 青 木 朗
弁理士西舘和之
弁理士 内 １）幸 男
弁理士 山 口 昭 之
第１図
第２図
第３図
１FIG. 1 is a perspective view of a conventional dielectric filter, and FIGS. 2 and 3 are perspective views showing different examples of the dielectric filter according to the present invention. 11... Dielectric plate, 12... Grounding conductor, 13...
...Resonance conductor, 14.14'...Input/output coupling line. Patent applicant Fujitsu Limited Patent agent Akira Aoki Patent attorney Kazuyuki Nishidate Patent attorney 1) Yukio Patent attorney Akiyuki Yamaguchi Figure 1 Figure 2 Figure 3 Figure 1
Claims (1)
体および入出力用結合線路を有し、その反対表面上をア
ース用導体で覆い、上記各共振用導体の一端を上記アー
ス用導体に接続する短絡端部とし、他端を開放端部とし
た誘電体フィルタにおいて、上記共振用導体の形状をそ
の開放端部が短絡端部方向に折返されて屈曲した形状と
したことを特徴とする誘電体フィルタ。 ２、特許請求の範囲第１項記載の誘、電体フィルタにお
いて、−表面をアース用導体で覆った別の誘電体板をそ
のアース用導体側表面との反対側衣゛面を上記共振用導
体を形成した誘電体板の共振用導体側表面に対面させて
接合したことを特徴とするＢ電体フィルタ。[Claims] ] A plurality of resonant conductors and input/output coupling lines are arranged in parallel on one surface of a dielectric plate, and the opposite surface is covered with a grounding conductor, and each of the resonant conductors is In a dielectric filter in which one end is a short-circuited end connected to the ground conductor and the other end is an open end, the shape of the resonance conductor is such that the open end is bent in the direction of the short-circuited end. A dielectric filter characterized by: 2. In the dielectric filter according to claim 1, - another dielectric plate whose surface is covered with a grounding conductor is provided with a coating surface on the opposite side of the grounding conductor side for the resonance. A B electric filter characterized in that a dielectric plate on which a conductor is formed is bonded so as to face the surface on the resonance conductor side.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20146381A JPS58103202A (en) | 1981-12-16 | 1981-12-16 | Dielectric filter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP20146381A JPS58103202A (en) | 1981-12-16 | 1981-12-16 | Dielectric filter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPS58103202A true JPS58103202A (en) | 1983-06-20 |
| JPS638641B2 JPS638641B2 (en) | 1988-02-24 |
Family
ID=16441501
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP20146381A Granted JPS58103202A (en) | 1981-12-16 | 1981-12-16 | Dielectric filter |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS58103202A (en) |
Cited By (17)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS6062202A (en) * | 1983-09-13 | 1985-04-10 | Murata Mfg Co Ltd | Filter using dielectric and its manufacture |
| US4625185A (en) * | 1983-03-17 | 1986-11-25 | Telettra, Telefonia Elettronica E Radio S.P.A. | Resonant circuit for the extraction of the clock frequency oscillation from the data flow |
| JPS6324701A (en) * | 1986-07-16 | 1988-02-02 | Murata Mfg Co Ltd | Distrubuted constant line device |
| JPS6485403A (en) * | 1987-09-28 | 1989-03-30 | Uniden Kk | Dielectric resonator |
| JPH0231501A (en) * | 1988-07-21 | 1990-02-01 | Matsushita Electric Ind Co Ltd | Dielectric resonator and apparatus using thereof |
| JPH02106701U (en) * | 1989-02-10 | 1990-08-24 | ||
| JPH0468901A (en) * | 1990-07-09 | 1992-03-04 | Matsushita Electric Ind Co Ltd | Microwave strip line resonator |
| JPH04306002A (en) * | 1991-02-15 | 1992-10-28 | Murata Mfg Co Ltd | Band pass filter |
| JPH04306001A (en) * | 1991-02-15 | 1992-10-28 | Murata Mfg Co Ltd | Resonator |
| JPH04306004A (en) * | 1991-02-15 | 1992-10-28 | Murata Mfg Co Ltd | Band pass filter |
| EP0510971A2 (en) * | 1991-04-24 | 1992-10-28 | Matsushita Electric Industrial Co., Ltd. | Dielectric filter |
| JPH04306003A (en) * | 1991-02-15 | 1992-10-28 | Murata Mfg Co Ltd | Band pass filter |
| JPH04306005A (en) * | 1991-02-15 | 1992-10-28 | Murata Mfg Co Ltd | Band pass filter |
| JPH066104A (en) * | 1992-06-22 | 1994-01-14 | Murata Mfg Co Ltd | Band pass filter |
| US5446430A (en) * | 1991-11-12 | 1995-08-29 | Fuji Electrochemical Co., Ltd. | Folded strip line type dielectric resonator and multilayer dielectric filter using the same |
| JP2003273603A (en) * | 2002-03-13 | 2003-09-26 | Kyocera Corp | Laminated strip line filter |
| WO2023139901A1 (en) * | 2022-01-19 | 2023-07-27 | 株式会社村田製作所 | Filter device |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5299750A (en) * | 1976-02-18 | 1977-08-22 | Toshiba Corp | Zone filter |
| JPS56163304U (en) * | 1980-04-30 | 1981-12-04 |
-
1981
- 1981-12-16 JP JP20146381A patent/JPS58103202A/en active Granted
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS5299750A (en) * | 1976-02-18 | 1977-08-22 | Toshiba Corp | Zone filter |
| JPS56163304U (en) * | 1980-04-30 | 1981-12-04 |
Cited By (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4625185A (en) * | 1983-03-17 | 1986-11-25 | Telettra, Telefonia Elettronica E Radio S.P.A. | Resonant circuit for the extraction of the clock frequency oscillation from the data flow |
| JPS6062202A (en) * | 1983-09-13 | 1985-04-10 | Murata Mfg Co Ltd | Filter using dielectric and its manufacture |
| JPH0315841B2 (en) * | 1983-09-13 | 1991-03-04 | Murata Manufacturing Co | |
| JPS6324701A (en) * | 1986-07-16 | 1988-02-02 | Murata Mfg Co Ltd | Distrubuted constant line device |
| JPS6485403A (en) * | 1987-09-28 | 1989-03-30 | Uniden Kk | Dielectric resonator |
| JPH0231501A (en) * | 1988-07-21 | 1990-02-01 | Matsushita Electric Ind Co Ltd | Dielectric resonator and apparatus using thereof |
| JPH02106701U (en) * | 1989-02-10 | 1990-08-24 | ||
| JPH0468901A (en) * | 1990-07-09 | 1992-03-04 | Matsushita Electric Ind Co Ltd | Microwave strip line resonator |
| JPH04306004A (en) * | 1991-02-15 | 1992-10-28 | Murata Mfg Co Ltd | Band pass filter |
| JPH04306001A (en) * | 1991-02-15 | 1992-10-28 | Murata Mfg Co Ltd | Resonator |
| JPH04306002A (en) * | 1991-02-15 | 1992-10-28 | Murata Mfg Co Ltd | Band pass filter |
| JPH04306003A (en) * | 1991-02-15 | 1992-10-28 | Murata Mfg Co Ltd | Band pass filter |
| JPH04306005A (en) * | 1991-02-15 | 1992-10-28 | Murata Mfg Co Ltd | Band pass filter |
| EP0510971A2 (en) * | 1991-04-24 | 1992-10-28 | Matsushita Electric Industrial Co., Ltd. | Dielectric filter |
| US5323128A (en) * | 1991-04-24 | 1994-06-21 | Matsushita Electric Industrial Co., Ltd. | Dielectric filter having inter-resonator coupling including both magnetic and electric coupling |
| US5396201A (en) * | 1991-04-24 | 1995-03-07 | Matsushita Electric Industrial Co., Ltd. | Dielectric filter having inter-resonator coupling including both magnetic and electric coupling |
| US5446430A (en) * | 1991-11-12 | 1995-08-29 | Fuji Electrochemical Co., Ltd. | Folded strip line type dielectric resonator and multilayer dielectric filter using the same |
| JPH066104A (en) * | 1992-06-22 | 1994-01-14 | Murata Mfg Co Ltd | Band pass filter |
| JP2003273603A (en) * | 2002-03-13 | 2003-09-26 | Kyocera Corp | Laminated strip line filter |
| WO2023139901A1 (en) * | 2022-01-19 | 2023-07-27 | 株式会社村田製作所 | Filter device |
Also Published As
| Publication number | Publication date |
|---|---|
| JPS638641B2 (en) | 1988-02-24 |
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