EP0047203A1 - Über eine grosse Bandbreite abstimmbares Mikrowellenfilter mit einem dielektrischen Resonator - Google Patents

Über eine grosse Bandbreite abstimmbares Mikrowellenfilter mit einem dielektrischen Resonator Download PDF

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Publication number
EP0047203A1
EP0047203A1 EP81401319A EP81401319A EP0047203A1 EP 0047203 A1 EP0047203 A1 EP 0047203A1 EP 81401319 A EP81401319 A EP 81401319A EP 81401319 A EP81401319 A EP 81401319A EP 0047203 A1 EP0047203 A1 EP 0047203A1
Authority
EP
European Patent Office
Prior art keywords
filter
dielectric
resonator
elements
resonators
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
EP81401319A
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English (en)
French (fr)
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EP0047203B1 (de
Inventor
Jacques Delaballe
Jean Fouillet
Yves Le Nohaic
Alexandre Osias
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.)
Thales SA
Original Assignee
Thomson CSF SA
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.)
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Publication date
Application filed by Thomson CSF SA filed Critical Thomson CSF SA
Priority to AT81401319T priority Critical patent/ATE16659T1/de
Publication of EP0047203A1 publication Critical patent/EP0047203A1/de
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Publication of EP0047203B1 publication Critical patent/EP0047203B1/de
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    • 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
    • H01P1/207—Hollow waveguide filters
    • H01P1/208—Cascaded cavities; Cascaded resonators inside a hollow waveguide structure
    • H01P1/2084—Cascaded cavities; Cascaded resonators inside a hollow waveguide structure with dielectric resonators
    • H—ELECTRICITY
    • H01—ELECTRIC ELEMENTS
    • H01P—WAVEGUIDES; RESONATORS, LINES, OR OTHER DEVICES OF THE WAVEGUIDE TYPE
    • H01P7/00—Resonators of the waveguide type
    • H01P7/10—Dielectric resonators

Definitions

  • the invention relates to microwave filters and more particularly to a microwave filter, with dielectric resonator, tunable over a large bandwidth.
  • Microwave transmission equipment for example military equipment, increasingly has to work successively on several tuning frequencies.
  • civilian fixed frequency transmission equipment can also be produced from tunable standard elements, tuning to the fixed working frequency being determined on site by adjusting these tunable standard elements.
  • the realization of such tunable elements, in particular the microwave filters required the implementation of tuning techniques such that the filter keeps determined characteristics in a tuning bandwidth as large as possible to cover with a standard element. given, a frequency bandwidth, without the characteristics of the element being degraded in this tuning band, in particular the response curve of the filter, the overvoltage coefficient, the coupling etc ...
  • the subject of the invention is a microwave filter with dielectric resonator, tunable over a large bandwidth, which satisfies these conditions.
  • a microwave filter with dielectric resonator comprising a waveguide and at least one dielectric resonator coupled to the guide, is mainly characterized in that each resonator comprises a first element, made of dielectric material, fixed by relative to the guide and a second element, made of dielectric material, movable relative to the guide and having with the first a facing surface, the distance between these two surfaces being variable and allowing the tuning of the filter over a large bandwidth.
  • a microwave filter is calculated as a function of a certain number of parameters including the working frequency, the width of the transmission or cut-off band, depending on whether they are band-pass filters or tape cutter.
  • the bandwidth determines the number of poles of the filter, and this number determines the number of resonators arranged along the direction of propagation as well as their spacing.
  • the resonators can be made of a dielectric material with a high dielectric constant but whose dimensions are stable as a function of the temperature. If this were not the case, the characteristics would be highly dependent on the temperature; what to avoid as much as possible.
  • the material must be of high dielectric constant for the effect of the resonator to be sufficient while keeping the dimensions fairly small, which makes it possible to limit the bulk of the materials.
  • the tuning frequency is adjusted for each resonator by a dielectric element, of dimensions close to those of the fixed element facing it, arranged at a variable distance from the first, the assembly forming the resonator.
  • the displacement of this second element modifies the tuning frequency and makes it possible to cover a wide band.
  • Figures 1 and 2 show an embodiment of a notch filter according to the invention; respectively in top view, cover removed, and in section, cover finished.
  • the housing 1 contains a coaxial line 2.
  • An input plug 3 and an output plug, 4, are fixed to the housing, the coaxial line 2 being connected to these two plugs.
  • Each resonator comprises a fixed element 5, consisting of a dielectric patch, placed at a certain distance from the coaxial line (these fixed elements being the only ones visible on the first view) glued to the bottom of the housing on a pad or a support washer. such as 6.
  • movable dielectric elements 8 roughly similar to the first come opposite the fixed dielectric elements such as 5.
  • Adjustment supports such as 9, associated with nuts 10 , accessible on the outer face of the cover 7, make it possible to vary the depression of these mobile dielectric elements, and therefore the distance d between the fixed element 5, and the mobile element, 8 forming the resonator.
  • the adjustment supports can be of any kind, metallic, dielectric, since they do not influence the propagation in the line from which they are quite far apart.
  • Such a filter works in the following manner.
  • the input plug is directly connected to coaxial line 2, and excites the line in coaxial TEM mode.
  • the box is only used to position with respect to this line the resonators which disturb the field lines by the effect of the plug circuits brought in series on the transmission line: the coupling of the resonator to this coaxial line of characteristic impedance, Z , brings back to the tuning frequency f a stopper circuit and the circuit then behaves like an open circuit and brings an attenuation of amplitude A at this frequency f.
  • the cross section of the dielectric tuning pad can be equal to, less than or greater than that of the fixed pad, the sinking required for a given variation in the tuning frequency being adjustable.
  • the relative dimensions of these two elements are therefore not critical. Similarly, the axial alignment of these two elements does not have to be achieved with great precision.
  • the movable tuning element made of a dielectric material like the fixed element, has a great influence on the characteristics of the resonator thus produced with the fixed element and the mobile element.
  • the frequency variation that can be obtained is of the order of 10% of the central frequency of the strip for a short stroke, of the same order as the stroke of the metal screws in agreement with the prior devices for which the frequency variation could only be of the order of 1% of the central frequency.
  • FIG. 3 represents a bandpass microwave filter, tunable over a large bandwidth, according to the invention.
  • the filter is made with dielectric resonators, the number of which determines the number of poles of the filter, before a strong dielectric constant.
  • the propagation mode is a TM 11 mode, guided in the microwave circuit formed by a box provided with its cover.
  • the filter comprises a housing 10, an input dipole 30 and an output dipole 40. It also has resonators, four in the figure, consisting of a fixed dielectric element, and a movable dielectric element. The movable elements are carried by rods also made of dielectric material, 85, accessible outside the housing by adjustment screws 90, locked by nuts 100.
  • the input signal excites the magnetic dipole mode of the most dielectric resonator close to the entry line. Transmission is carried out step by step by coupling the magnetic field lines from a dielectric resonator to the next resonator by evanescent waves, up to the output line.
  • the coupling coefficient between two consecutive resonators is a function of the distance s which separates them.
  • each resonator is in practice made up of the fixed dielectric element 5, of the mobile dielectric element which faces it, 8, and of the dielectric support rod to which the latter is linked.
  • the tuning frequency of this resonator depends of the distance d which separates the facing elements.
  • the electric field existing in the interval between the two cylinders of dielectric material is all the greater as the ratio . (D being the diameter of the cylinders and h their height) is large.
  • the variation in the tuning frequency will be all the greater the lower the height of the movable cylinder.
  • the variation in tuning frequency with respect to the center frequency of the tuning band can be of the order of 10% to 15%.
  • the dimensions of the dielectric material elements and the spacing of the resonators are chosen so that the overvoltage coefficient remains high. Thus should, if possible, vary between 0.3 and 1.
  • the dielectric material chosen to constitute the resonators has as large a dielectric constant as possible, the limitation being generally imposed by the temperature resistance, so that the resonators can have such a small volume as possible taking into account the required performance (high working frequencies in the 3.8 to 4.2 GHz and 6.4 to 7.1 GHz frequency bands).
  • the variation in tuning frequency with respect to the central frequency of the band need not always be of the order of 10%.
  • this variation of the tuning frequency does not have to exceed 5%, it is possible to very significantly reduce the bandwidth variations due to modifications of the tuning frequency, for this the dielectric constant of the moving elements is chosen between 15 and 20 and no longer of the order of 40, on the other hand the dielectric constant of the fixed elements remains of the order of 40; thus the disturbance brought into the electromagnetic field around the fixed elements of the resonators by the approach of the mobile elements is reduced.
  • each resonator then comprises a fixed dielectric element and a mobile dielectric element separated by a variable distance to modify the tuning frequency.

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EP81401319A 1980-08-29 1981-08-19 Über eine grosse Bandbreite abstimmbares Mikrowellenfilter mit einem dielektrischen Resonator Expired EP0047203B1 (de)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AT81401319T ATE16659T1 (de) 1980-08-29 1981-08-19 Ueber eine grosse bandbreite abstimmbares mikrowellenfilter mit einem dielektrischen resonator.

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR8018771 1980-08-29
FR8018771A FR2489605A1 (fr) 1980-08-29 1980-08-29 Filtre hyperfrequence a resonateur dielectrique, accordable dans une grande largeur de bande, et circuit comportant un tel filtre

Publications (2)

Publication Number Publication Date
EP0047203A1 true EP0047203A1 (de) 1982-03-10
EP0047203B1 EP0047203B1 (de) 1985-11-21

Family

ID=9245503

Family Applications (1)

Application Number Title Priority Date Filing Date
EP81401319A Expired EP0047203B1 (de) 1980-08-29 1981-08-19 Über eine grosse Bandbreite abstimmbares Mikrowellenfilter mit einem dielektrischen Resonator

Country Status (6)

Country Link
US (1) US4459570A (de)
EP (1) EP0047203B1 (de)
JP (1) JPS5776901A (de)
AT (1) ATE16659T1 (de)
DE (1) DE3172989D1 (de)
FR (1) FR2489605A1 (de)

Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2546340A1 (fr) * 1983-05-20 1984-11-23 Thomson Csf Filtre hyperfrequence coupe-bande accordable, de type coaxial, a resonateurs dielectriques
EP0346806A1 (de) * 1988-06-17 1989-12-20 Alcatel Telspace Bandpassfilter mit dielektrischen Resonatoren
CN111384538B (zh) * 2018-12-29 2021-12-24 华为技术有限公司 一种滤波器及基站

Families Citing this family (29)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2539565A1 (fr) * 1983-01-19 1984-07-20 Thomson Csf Filtre hyperfrequence accordable, a resonateurs dielectriques en mode tm010
JPS59198003A (ja) * 1983-04-26 1984-11-09 Nec Corp 誘電体共振器を使用した共振回路
US4618836A (en) * 1984-12-24 1986-10-21 Motorola, Inc. Wide band dielectric resonator oscillator having temperature compensation
JPS61280104A (ja) * 1985-06-05 1986-12-10 Murata Mfg Co Ltd 誘電体共振器装置
FR2583597A1 (fr) * 1985-06-13 1986-12-19 Alcatel Thomson Faisceaux Filtre passe-bande hyperfrequences en mode evanescent
US5283462A (en) * 1991-11-04 1994-02-01 Motorola, Inc. Integrated distributed inductive-capacitive network
JPH05145311A (ja) * 1992-04-24 1993-06-11 Murata Mfg Co Ltd 誘電体共振器装置
IT1264648B1 (it) * 1993-07-02 1996-10-04 Sits Soc It Telecom Siemens Risonatore sintonizzzabile per oscillatori e filtri alle microonde
US6147577A (en) * 1998-01-15 2000-11-14 K&L Microwave, Inc. Tunable ceramic filters
SE512513C2 (sv) 1998-06-18 2000-03-27 Allgon Ab Anordning för avstämning av en dialektrisk resonator
US6559740B1 (en) 2001-12-18 2003-05-06 Delta Microwave, Inc. Tunable, cross-coupled, bandpass filter
US7310031B2 (en) 2002-09-17 2007-12-18 M/A-Com, Inc. Dielectric resonators and circuits made therefrom
US7057480B2 (en) * 2002-09-17 2006-06-06 M/A-Com, Inc. Cross-coupled dielectric resonator circuit
US20040257176A1 (en) * 2003-05-07 2004-12-23 Pance Kristi Dhimiter Mounting mechanism for high performance dielectric resonator circuits
US20050200437A1 (en) * 2004-03-12 2005-09-15 M/A-Com, Inc. Method and mechanism for tuning dielectric resonator circuits
US7088203B2 (en) * 2004-04-27 2006-08-08 M/A-Com, Inc. Slotted dielectric resonators and circuits with slotted dielectric resonators
US7388457B2 (en) 2005-01-20 2008-06-17 M/A-Com, Inc. Dielectric resonator with variable diameter through hole and filter with such dielectric resonators
US7583164B2 (en) * 2005-09-27 2009-09-01 Kristi Dhimiter Pance Dielectric resonators with axial gaps and circuits with such dielectric resonators
US7352264B2 (en) * 2005-10-24 2008-04-01 M/A-Com, Inc. Electronically tunable dielectric resonator circuits
US7705694B2 (en) * 2006-01-12 2010-04-27 Cobham Defense Electronic Systems Corporation Rotatable elliptical dielectric resonators and circuits with such dielectric resonators
US7719391B2 (en) * 2006-06-21 2010-05-18 Cobham Defense Electronic Systems Corporation Dielectric resonator circuits
US20080272860A1 (en) * 2007-05-01 2008-11-06 M/A-Com, Inc. Tunable Dielectric Resonator Circuit
US7456712B1 (en) * 2007-05-02 2008-11-25 Cobham Defense Electronics Corporation Cross coupling tuning apparatus for dielectric resonator circuit
FR2994029B1 (fr) * 2012-07-27 2014-07-25 Thales Sa Filtre accordable en frequence a resonateur dielectrique
JP6006079B2 (ja) * 2012-10-23 2016-10-12 Ｎｅｃエンジニアリング株式会社 チューナブル帯域通過フィルタ
WO2017006516A1 (ja) * 2015-07-07 2017-01-12 日本電気株式会社 帯域通過フィルタ及びその制御方法
CN105489989B (zh) * 2015-12-24 2018-06-26 中国电子科技集团公司第五十四研究所 一种大功率波导电调滤波器
US10613254B2 (en) 2017-05-24 2020-04-07 Uchicago Argonne, Llc Ultrathin, polarization-independent, achromatic metalens for focusing visible light
US10324314B2 (en) * 2017-05-24 2019-06-18 Uchicago Argonne, Llc Ultra-flat optical device with high transmission efficiency

Citations (1)

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FR2355403A1 (fr) * 1976-06-14 1978-01-13 Murata Manufacturing Co Filtre electrique de branchement

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US3475642A (en) * 1966-08-10 1969-10-28 Research Corp Microwave slow wave dielectric structure and electron tube utilizing same
CA921692A (en) * 1969-12-11 1973-02-27 F. Rendle David Microwave devices
JPS5416151A (en) * 1977-07-06 1979-02-06 Murata Manufacturing Co Filter for coaxial line

Patent Citations (1)

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Publication number Priority date Publication date Assignee Title
FR2355403A1 (fr) * 1976-06-14 1978-01-13 Murata Manufacturing Co Filtre electrique de branchement

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
IEEE MTT-S International Microwave Symposium, 21-23 Juin 1977, San Diego New York, US J.K. PLOURDE et al.: "Microwave Dielectric Resonator Filters Utilizing Ba2Ti9o20 Ceramics", pages 290-293 * en entier * *
IEEE Transactions on Microwave Theory and Techniques, Vol. MTT-27 No. 3, Mars 1979 New York, US M.W. POSPIESZALSKI: "Cylindrical Dielectric Resonators and their Applications in TEM line Microwave Circuits", pages 233-238 * en entier * *
PATENT ABSTRACTS OF JAPAN, Vol. 4, No. 14, 31 Janvier 1980 page 131, E-169 & JP-A-54 154 960 (Nippon Denki K.K.) 06-12-1979 *

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2546340A1 (fr) * 1983-05-20 1984-11-23 Thomson Csf Filtre hyperfrequence coupe-bande accordable, de type coaxial, a resonateurs dielectriques
US4620168A (en) * 1983-05-20 1986-10-28 Thomson Csf Coaxial type tunable hyperfrequency elimination band filter comprising of dielectric resonators
EP0346806A1 (de) * 1988-06-17 1989-12-20 Alcatel Telspace Bandpassfilter mit dielektrischen Resonatoren
FR2633118A1 (fr) * 1988-06-17 1989-12-22 Alcatel Thomson Faisceaux Filtre passe-bande a resonateurs dielectriques
CN111384538B (zh) * 2018-12-29 2021-12-24 华为技术有限公司 一种滤波器及基站

Also Published As

Publication number Publication date
FR2489605B1 (de) 1984-05-04
FR2489605A1 (fr) 1982-03-05
EP0047203B1 (de) 1985-11-21
ATE16659T1 (de) 1985-12-15
US4459570A (en) 1984-07-10
DE3172989D1 (en) 1986-01-02
JPS5776901A (en) 1982-05-14

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