JPH0738523B2 - Low pass filter - Google Patents
Low pass filterInfo
- Publication number
- JPH0738523B2 JPH0738523B2 JP26670289A JP26670289A JPH0738523B2 JP H0738523 B2 JPH0738523 B2 JP H0738523B2 JP 26670289 A JP26670289 A JP 26670289A JP 26670289 A JP26670289 A JP 26670289A JP H0738523 B2 JPH0738523 B2 JP H0738523B2
- Authority
- JP
- Japan
- Prior art keywords
- pass filter
- conductor
- portions
- wide
- low
- 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 - Fee Related
Links
Landscapes
- Control Of Motors That Do Not Use Commutators (AREA)
Description
【発明の詳細な説明】 〔産業上の利用分野〕 この発明は、主としてVHF帯、UHF帯及びマイクロ波帯で
用いられる低域通過フィルタに関するものである。TECHNICAL FIELD The present invention relates to a low-pass filter mainly used in the VHF band, the UHF band and the microwave band.
第４図は例えばマイクロウエーブ フィルターズ、イン
ピーダンス−マッチング ネットワークス，アンド カ
プリング ストラクチャズ（MICROWAVE FILTERS, IMPED
ANCE-MATCHING NHTWORKS,AND COUPLING STRUCTURES）P
P.365-380,1964年マグロウヒル（McGraw-Hill）に示さ
れた従来の低域通過フィルタを示す一部を切欠いた斜視
図であり、図において、１は円筒状を成す外導体、２は
外導体１の中心軸に沿って配された内導体、３は内導体
２の３個所に設けられた円板状の内導体、４は内導体３
と外導体１との間に介在された誘電体リング、５は内導
体２と外導体１とから構成される同軸線路の高インピー
ダンス部、６は内導体３と外導体１と誘電体リング４と
から構成される同軸線路の低インピーダンス部、７は入
出力端の内導体、８は入出力端の外導体である。Fig. 4 shows, for example, microwave filters, impedance-matching networks, and coupling structures (MICROWAVE FILTERS, IMPED).
ANCE-MATCHING NHTWORKS, AND COUPLING STRUCTURES) P
P.365-380, 1964 is a partially cutaway perspective view showing a conventional low-pass filter shown in McGraw-Hill, in which 1 is a cylindrical outer conductor and 2 is a cylindrical outer conductor. Inner conductors 3 arranged along the central axis of the outer conductor 1, 3 are disc-shaped inner conductors provided at three positions of the inner conductor 2, and 4 are inner conductors 3.
A dielectric ring 5 interposed between the outer conductor 1 and the outer conductor 1 is a high impedance portion of a coaxial line composed of the inner conductor 2 and the outer conductor 1, and 6 is an inner conductor 3, the outer conductor 1, and a dielectric ring 4. Is a low impedance part of the coaxial line, 7 is an inner conductor at the input / output end, and 8 is an outer conductor at the input / output end.
次に動作について説明する。Next, the operation will be described.
内導体３は、同じ長さの誘電体リング４を外導体３との
間に挟み込むことによって接触により固定されている。
高インピーダンス部５は、内導体２の直径が小さく内導
体２と外導体１との間隔が広いため、高インピーダンス
となっている。一方、低インピーダンス部６は、内導体
３の直径が大きく内導体３と外導体１との間隔が狭い
上、内導体３と外導体１との間に誘電体リング４が挿入
されているため、低インピーダンスとなっている。The inner conductor 3 is fixed by contact by sandwiching a dielectric ring 4 having the same length between the inner conductor 3 and the outer conductor 3.
The high impedance portion 5 has high impedance because the diameter of the inner conductor 2 is small and the distance between the inner conductor 2 and the outer conductor 1 is wide. On the other hand, in the low impedance portion 6, the inner conductor 3 has a large diameter and the distance between the inner conductor 3 and the outer conductor 1 is narrow, and the dielectric ring 4 is inserted between the inner conductor 3 and the outer conductor 1. , Has a low impedance.
第４図に示される従来の低域通過フィルタは、第５図の
低域通過フィルタの等価回路で表わされる。第５図にお
いてL1〜L5はインダクタンスであり、第４図の高インピ
ーダンス部５に対応する。これらのインダクタンスL1〜
L5は、内導体２の長さと外導体１に対する直径の比によ
って大きさが決定される。また、C1〜C4はキャパシタン
スであり、第４図の低インピーダンス部６に対応する。
これらのキャパシタンスC1〜４は、内導体３の長さと外
導体１に対する直径の比および誘電体リング４の誘電率
によって大きさが決定される。The conventional low pass filter shown in FIG. 4 is represented by an equivalent circuit of the low pass filter shown in FIG. In FIG. 5, L 1 to L 5 are inductances and correspond to the high impedance part 5 in FIG. These inductances L 1 ~
The size of L 5 is determined by the ratio of the length of the inner conductor 2 to the diameter of the outer conductor 1. Further, C 1 to C 4 are capacitances and correspond to the low impedance portion 6 in FIG.
These capacitances C 1 to 4 are sized by the ratio of the length of the inner conductor 3 to the diameter of the outer conductor 1 and the dielectric constant of the dielectric ring 4.
以上のように第４図に示される従来の低域通過フィルタ
は、直列のインダクタンスとして働く高インピーダンス
部５と並列のサセプタンスとして働く低インピーダンス
部６とが交互に接続されており、第５図の低域通過フィ
ルタの等価回路で表わされるので、低域通過フィルタの
機能を有する。As described above, in the conventional low-pass filter shown in FIG. 4, the high-impedance portion 5 that acts as a series inductance and the low-impedance portion 6 that acts as a susceptance in parallel are alternately connected. Since it is represented by an equivalent circuit of a low pass filter, it has the function of a low pass filter.
従来の低域通過フィルタは以上のように構成されている
ので、高インピーダンス部５と低インピーダンス部６と
が交互に直線状に並べられた構成であり、かつ、誘電体
の形状が複雑であった。一般に誘電率の大きなセラミッ
ク材は硬くリング形状などの加工が難しいため、このよ
うな材料を誘電体リング４として利用することができ
ず、このため、低インピーダンス部６を長くする必要が
あり、この結果フィルタ全体の長さも長くなるという問
題点があった。また、互いに隣接する低インピーダンス
部６の間隔が広いため、２つの低インピーダンス部６間
の静電容量によるキャパシタンスを利用して有極特性を
得ることが難しいという問題点があった。さらに、内導
体2,3と外導体１とが同心円状に配置される必要がある
ため、寸法精度のばらつきにより安定した品質のものが
得にくいなどの課題があった。Since the conventional low-pass filter is configured as described above, the high-impedance portion 5 and the low-impedance portion 6 are alternately arranged in a straight line, and the shape of the dielectric is complicated. It was Generally, since a ceramic material having a large dielectric constant is hard and difficult to be processed into a ring shape or the like, such a material cannot be used as the dielectric ring 4. Therefore, it is necessary to lengthen the low impedance portion 6. As a result, there is a problem that the length of the entire filter becomes long. Further, there is a problem that it is difficult to obtain polar characteristics by utilizing the capacitance due to the electrostatic capacitance between the two low impedance portions 6 because the distance between the low impedance portions 6 adjacent to each other is wide. Further, since the inner conductors 2 and 3 and the outer conductor 1 need to be arranged concentrically, there is a problem that it is difficult to obtain stable quality due to variation in dimensional accuracy.
この発明は上記のような課題を解消するためになされた
もので、小形で寸法精度が良く安定した品質のものが得
易く、また、有極特性による急峻な帯域外減衰性を有す
る低域通過フィルタを得ることを目的とする。The present invention has been made in order to solve the above problems, and it is easy to obtain a small size with good dimensional accuracy and stable quality, and a low-pass filter having steep out-of-band attenuation due to polar characteristics. The purpose is to get a filter.
この発明に係る低域通過フィルタは、平行に配置された
外導体の相互間のほぼ中間に、幅狭部と幅広部とが交互
に直列接続されて構成され、かつ、上記幅広部が一直線
に並ぶように蛇行して配置された内導体を設け、上記幅
広部と上記外導体との間に誘電体棒を挿入すると共に、
隣接する上記幅広部を相互に結合が生じるように接近し
て配置したものである。The low-pass filter according to the present invention is configured such that a narrow portion and a wide portion are alternately connected in series at approximately the middle between outer conductors arranged in parallel, and the wide portion is in a straight line. Providing an inner conductor arranged in a meandering manner so as to line up, while inserting a dielectric rod between the wide portion and the outer conductor,
Adjacent wide portions are arranged close to each other so that they are coupled to each other.
この発明における内導体は、蛇行して配置されているの
で、フィルタの長さが短くなり、また、一直線上に並ぶ
幅広部と外導体との間に挿入される誘電体棒が共通とな
り、簡単な構造となるため、高誘電率のセラミック材を
用いて幅広部を短くでき、フィルタが小形になる。ま
た、隣接する幅広部が接近しているので、相互の結合容
量により有極特性が得られ、帯域外減衰特性が急峻にな
る。さらに、内導体を誘電体基板上にエッチングにより
形成できるので、寸法精度の良い安定した品質の物が得
られる。Since the inner conductor according to the present invention is arranged in a meandering manner, the length of the filter is shortened, and the dielectric rod inserted between the wide portion and the outer conductor aligned in a straight line is common, which is easy. With such a structure, the wide portion can be shortened by using a ceramic material having a high dielectric constant, and the filter can be downsized. Further, since the adjacent wide portions are close to each other, a polar characteristic is obtained due to mutual coupling capacitance, and the out-of-band attenuation characteristic becomes steep. Furthermore, since the inner conductor can be formed on the dielectric substrate by etching, a product with good dimensional accuracy and stable quality can be obtained.
以下、この発明の一実施例を図について説明する。 An embodiment of the present invention will be described below with reference to the drawings.
第１図及び第２図において、10は直方体の筐体状を成す
外導体であって、内導体12を間にして平行な導体部分を
有する。11は外導体10の内部を中央から２つに仕切るよ
うに設けられた誘電体から成る基板、12は基板11の両面
に対向して蛇行するパターンにエッチングにより形成さ
れた箔状の内導体で、それぞれ複数個の幅広部12aと幅
狭部12b,12cとから構成されている。幅広部12aはその４
個が互いに近接して略一直線上に配列され、幅狭部12b
はその３個が幅広部12aを電気的に直列に接続するよう
に設けられ、それぞれ２個所で直角に屈曲形成されてい
る。また、幅狭部12cは両端の幅広部12aから導出されて
いる。In FIGS. 1 and 2, reference numeral 10 denotes an outer conductor having a rectangular parallelepiped housing shape and having parallel conductor portions with an inner conductor 12 interposed therebetween. Reference numeral 11 denotes a substrate made of a dielectric material provided so as to divide the inside of the outer conductor 10 into two parts from the center, and 12 denotes a foil-shaped inner conductor formed by etching in a meandering pattern facing both surfaces of the substrate 11. Each is composed of a plurality of wide portions 12a and narrow portions 12b and 12c. Wide part 12a is part 4
The individual pieces are arranged close to each other in a substantially straight line, and the narrow portion 12b
Three of them are provided so as to electrically connect the wide portions 12a in series, and each of them is bent and formed at two right angles. The narrow portion 12c is led out from the wide portions 12a at both ends.
13は基板１の両面の幅広部12aと外導体10の内面との間
に介在された誘電体棒、14,15は外導体10に設けられた
入出力端子で、それぞれ上記幅狭部12cと接続されてい
る。５は幅狭部12b,12cと外導体10とから構成される高
インピーダンス部、６は幅広部12aと外導体10と誘電体
棒13とから構成される低インピーダンス部である。Reference numeral 13 is a dielectric rod interposed between the wide portions 12a on both sides of the substrate 1 and the inner surface of the outer conductor 10, and 14 and 15 are input / output terminals provided on the outer conductor 10, which are respectively the narrow portions 12c. It is connected. Reference numeral 5 is a high impedance portion composed of the narrow portions 12b and 12c and the outer conductor 10, and 6 is a low impedance portion composed of the wide portion 12a, the outer conductor 10 and the dielectric rod 13.
次に動作について説明する。Next, the operation will be described.
第１図に示す低域通過フィルタは第３図に示す低域通過
フィルタの等価回路で表わされる。第３図において、L1
〜L5はインダクタンスであり、高インピーダンス部５に
対応し、幅狭部12b,12cの線路幅によって大きさが決定
される。C1〜C4はキャパシタンスであり、低インピーダ
ンス部６に対応し、幅広部12aの線路幅および誘電体棒1
3の誘電率によって大きさが決定される。また、Cp2〜Cp
4は極を得るためのキャパシタンスであり、隣接する低
インピーダンス部６間の結合容量に対応し、隣接する幅
広部12a間の距離によって大きさが決定される。The low pass filter shown in FIG. 1 is represented by an equivalent circuit of the low pass filter shown in FIG. In FIG. 3, L 1
˜L 5 is an inductance, which corresponds to the high impedance portion 5, and its size is determined by the line widths of the narrow portions 12b and 12c. C 1 to C 4 are capacitances, which correspond to the low impedance portion 6, line width of the wide portion 12a and the dielectric rod 1
The size is determined by the dielectric constant of 3. Also, Cp 2 ~ Cp
Reference numeral 4 denotes a capacitance for obtaining a pole, which corresponds to the coupling capacitance between the adjacent low impedance portions 6 and whose size is determined by the distance between the adjacent wide portions 12a.
以上のように、第１図のフィルタは従来の場合と同様に
低域通過フィルタの機能を有する。As described above, the filter of FIG. 1 has the function of a low pass filter as in the conventional case.
インダクタンスLi（ｉ＝1,2……）とキャパシタンスCpi
とは、共振周波数 の並列共振回路を構成する。このため、フィルタの通過
特性はf0に減衰極を生じる。従って、このf0を阻止帯域
の適当な位置に選ぶことにより急峻な帯域外減衰特性が
得られる。Inductance Li (i = 1,2 ...) and capacitance Cpi
Is the resonance frequency To form a parallel resonant circuit. Therefore, the pass characteristic of the filter has an attenuation pole at f 0 . Therefore, a steep out-of-band attenuation characteristic can be obtained by selecting this f 0 at an appropriate position in the stop band.
また、誘電体棒13は形状が単純なため、材料に高誘電率
のセラミック材を使用でき、フィルタのしゃ断周波数を
低くできるとともに、低インピーダンス部６を短くでき
る。Further, since the dielectric rod 13 has a simple shape, a ceramic material having a high dielectric constant can be used as a material, the cutoff frequency of the filter can be lowered, and the low impedance portion 6 can be shortened.
なお、上記実施例では、高インピーダンス部５と低イン
ピーダンス部６の数の合計が９個の場合を示したが、２
〜８個あるいは10個以上でもよく、上記実施例と同様の
効果を奏する。In the above embodiment, the total number of the high impedance portions 5 and the low impedance portions 6 is nine, but 2
8 to 10 or more may be provided, and the same effect as that of the above embodiment is obtained.
また、上記実施例では、内導体12の幅狭部12b,12cと幅
広部12aが入出力端のどちらの側からも幅狭部−幅広部
の順に接続された場合について示したが、両側とも幅広
部−幅狭部の順あるいは片側のみ幅広部−幅狭部の順に
接続された場合でもよく、上記実施例と同様の効果を奏
する。Further, in the above embodiment, the narrow portions 12b, 12c and the wide portion 12a of the inner conductor 12 have been described as being connected in order of the narrow portion-the wide portion from either side of the input / output end, but on both sides. The wide portion-narrow portion may be connected in this order, or only one side may be connected in the order of the wide portion-narrow portion, and the same effect as that of the above-described embodiment is obtained.
以上のようにこの発明によれば、低域通過フィルタの内
導体を、幅狭部と幅広部とを交互に直列接続して構成
し、かつ、上記幅広部が一直線上に並ぶように幅狭部を
屈曲形成して配置し、上記幅広部と外導体との間に隙間
なく誘電体棒を挿入すると共に、隣接する上記幅広部を
相互に結合が生じるように接近して配置するように構成
したので、小型で寸法精度が良く、安定した品質が得ら
れるとともに幅広部間の静電容量を利用して有極特性を
実現することができ、帯域外減衰特性の急峻なものが得
られる等の効果がある。As described above, according to the present invention, the inner conductor of the low-pass filter is configured by alternately connecting the narrow portions and the wide portions in series, and the narrow portions are arranged so that the wide portions are aligned. The bent portions are arranged in a bent manner, the dielectric rod is inserted between the wide portion and the outer conductor without a gap, and the adjacent wide portions are arranged close to each other so that mutual coupling occurs. As a result, the size is small, the dimensional accuracy is good, stable quality is obtained, and the polar characteristics can be realized by using the capacitance between the wide parts, and a steep out-of-band attenuation characteristic can be obtained. Has the effect of.
第１図はこの発明の一実施例による低域通過フィルタを
示す一部切欠いた斜視図、第２図は第１図のII-II線断
面図、第３図は同フィルタの等価回路図、第４図は従来
の低域通過フィルタを示す一部切欠いた斜視図、第５図
は同フィルタの等価回路図である。 10は外導体、12は内導体、12aは幅広部、12b,12cは幅狭
部、13は誘電体棒、５は高インピーダンス部、６は低イ
ンピーダンス部。 なお、図中、同一符号は同一または相当部分を示す。FIG. 1 is a partially cutaway perspective view showing a low-pass filter according to an embodiment of the present invention, FIG. 2 is a sectional view taken along line II-II of FIG. 1, and FIG. 3 is an equivalent circuit diagram of the filter. FIG. 4 is a partially cutaway perspective view showing a conventional low pass filter, and FIG. 5 is an equivalent circuit diagram of the filter. 10 is an outer conductor, 12 is an inner conductor, 12a is a wide portion, 12b and 12c are narrow portions, 13 is a dielectric rod, 5 is a high impedance portion, and 6 is a low impedance portion. In the drawings, the same reference numerals indicate the same or corresponding parts.
───────────────────────────────────────────────────── フロントページの続き (72)発明者 川浦 義治 東京都千代田区内幸町１丁目１番６号 日 本電信電話株式会社内 (72)発明者 宮▲崎▼ 守泰 神奈川県鎌倉市大船５丁目１番１号 三菱 電機株式会社情報電子研究所内 (72)発明者 浅尾 英喜 神奈川県鎌倉市大船５丁目１番１号 三菱 電機株式会社情報電子研究所内 (72)発明者 石田 修己 神奈川県鎌倉市大船５丁目１番１号 三菱 電機株式会社情報電子研究所内 (56)参考文献 特開 昭62−196902（ＪＰ，Ａ) 特開 昭54−94258（ＪＰ，Ａ) 特開 昭58−73201（ＪＰ，Ａ) 実開 昭64−28001（ＪＰ，Ｕ) 実開 昭57−39103（ＪＰ，Ｕ) ─────────────────────────────────────────────────── ─── Continuation of front page (72) Yoshiharu Kawaura 1-6, Uchisaiwaicho, Chiyoda-ku, Tokyo Nihon Telegraph and Telephone Corp. No. 1 Mitsubishi Electric Corporation Information & Electronics Laboratory (72) Inventor Hideki Asao 5-1-1 Ofuna, Kamakura City, Kanagawa Prefecture Mitsubishi Electric Corporation Information & Electronics Laboratory (72) Inventor Shumi Ishida Ofuna, Kamakura, Kanagawa Prefecture 5-1-1, Information Technology Laboratory, Mitsubishi Electric Corporation (56) Reference JP-A-62-196902 (JP, A) JP-A-54-94258 (JP, A) JP-A-58-73201 (JP, A) Actual opening Sho 64-28001 (JP, U) Actual opening Sho 57-39103 (JP, U)
Claims (1)
互間の略中央部に蛇行して配された内導体の一部を構成
し、互いに近接して略一直線上に配された複数個の幅広
部と、上記内導体の他部を構成し上記複数個の幅広部を
電気的に直列接続する屈曲形成された複数個の幅狭部
と、上記複数個の幅広部と上記外導体との間に介在する
誘電体棒とを備えた低域通過フィルタ。1. An outer conductor arranged in parallel and a part of an inner conductor arranged meandering in a substantially central portion between the outer conductors, and arranged in close proximity to each other in a substantially straight line. A plurality of wide portions, a plurality of bent narrow portions that constitute another portion of the inner conductor and electrically connect the plurality of wide portions in series, the plurality of wide portions and the outer portion. A low-pass filter having a dielectric rod interposed between a conductor and the conductor.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP26670289A JPH0738523B2 (en) | 1989-10-13 | 1989-10-13 | Low pass filter |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP26670289A JPH0738523B2 (en) | 1989-10-13 | 1989-10-13 | Low pass filter |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| JPH03128501A JPH03128501A (en) | 1991-05-31 |
| JPH0738523B2 true JPH0738523B2 (en) | 1995-04-26 |
Family
ID=17434496
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP26670289A Expired - Fee Related JPH0738523B2 (en) | 1989-10-13 | 1989-10-13 | Low pass filter |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPH0738523B2 (en) |
Families Citing this family (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP3610861B2 (en) | 2000-01-31 | 2005-01-19 | 三菱電機株式会社 | Low pass filter |
| US7437187B1 (en) * | 2000-10-30 | 2008-10-14 | Conductus, Inc. | Superconductive filter with capacitive patches providing reduced cross-coupling |
| US8508318B2 (en) | 2007-03-16 | 2013-08-13 | Nec Corporation | Transmission line filter |
| JP4913217B2 (en) * | 2010-01-05 | 2012-04-11 | 島田理化工業株式会社 | Low pass filter |
-
1989
- 1989-10-13 JP JP26670289A patent/JPH0738523B2/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| JPH03128501A (en) | 1991-05-31 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1146068C (en) | Balanced dielectric filter | |
| JP4710174B2 (en) | Balanced LC filter | |
| US6529102B2 (en) | LC filter circuit and laminated type LC filter | |
| GB2308747A (en) | LC resonant device | |
| JPS61262301A (en) | Ceramic filter and wireless tranceiver using the same | |
| JPH0481891B2 (en) | ||
| JPH0666569B2 (en) | Radial and axial power dividers and combiners | |
| JPH06501604A (en) | Multistage monolithic ceramic bandstop filter with isolated filter stages | |
| JPH0738523B2 (en) | Low pass filter | |
| US5216394A (en) | Dielectric multi-line resonator including a coupling conductor line mainly inductively coupled to a resonator conductor line | |
| JPS5826842B2 (en) | interdigital filter | |
| JP3603826B2 (en) | Spiral line assembly element, resonator, filter, duplexer and high frequency circuit device | |
| JP2630387B2 (en) | Dielectric filter | |
| JP2721626B2 (en) | Multilayer dielectric filter | |
| JP3595715B2 (en) | Balanced dielectric filter | |
| JP2830638B2 (en) | Resonator | |
| EP0568370B1 (en) | Dielectric filter device | |
| JPS6230402A (en) | Band elimination filter | |
| JPH04220001A (en) | Dielectric filter | |
| JP2806682B2 (en) | Multilayer dielectric filter | |
| JPH05243810A (en) | Layered type dielectric filter | |
| JP3193101B2 (en) | Multilayer dielectric filter | |
| JPH03205903A (en) | Polar type low-pass filter | |
| JPH0758511A (en) | Dielectric filter | |
| JPH0535601Y2 (en) |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| LAPS | Cancellation because of no payment of annual fees |