EP0250858A2 - Microwave filter with multiple coupled cavity resonators - Google Patents

Microwave filter with multiple coupled cavity resonators Download PDF

Info

Publication number
EP0250858A2
EP0250858A2 EP87107534A EP87107534A EP0250858A2 EP 0250858 A2 EP0250858 A2 EP 0250858A2 EP 87107534 A EP87107534 A EP 87107534A EP 87107534 A EP87107534 A EP 87107534A EP 0250858 A2 EP0250858 A2 EP 0250858A2
Authority
EP
European Patent Office
Prior art keywords
cavity
cavity resonators
resonators
microwave filter
coupling
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
EP87107534A
Other languages
German (de)
French (fr)
Other versions
EP0250858A3 (en
EP0250858B1 (en
Inventor
Uwe Dipl.-Ing. Rosenberg
Dieter Dipl.-Ing. Wolk
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.)
Bosch Telecom GmbH
Original Assignee
ANT Nachrichtentechnik GmbH
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 ANT Nachrichtentechnik GmbH filed Critical ANT Nachrichtentechnik GmbH
Publication of EP0250858A2 publication Critical patent/EP0250858A2/en
Publication of EP0250858A3 publication Critical patent/EP0250858A3/en
Application granted granted Critical
Publication of EP0250858B1 publication Critical patent/EP0250858B1/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

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
    • H01P1/207—Hollow waveguide filters
    • H01P1/208—Cascaded cavities; Cascaded resonators inside a hollow waveguide structure

Definitions

  • the present invention relates to a microwave filter which has a plurality of cavity resonators which are coupled to one another via coupling openings in their side walls running parallel to the direction of wave propagation.
  • Such a microwave filter is known from DE-OS 26 43 094. With this microwave filter, all coupled cylindrical cavity resonators are operated in TE 011 wave mode in order to achieve the highest possible filter quality.
  • the cavity resonators of the known microwave filter are assembled in a rather complicated constellation, so that in order to achieve an elliptical filter characteristic, in addition to the couplings of the cavity resonators lined up in the energy flow direction, positive or negative overcouplings between other cavity resonators can also be realized.
  • the invention is based on the object of specifying a microwave filter of the type mentioned at the outset, which consists of a simple, space-saving cavity construction which allows a large number of couplings between the individual cavity resonators.
  • the cavity resonator constellation according to the invention leads to a space-saving, compact microwave filter.
  • FIG. 1 shows a microwave filter which consists of six cylindrical cavity resonators H1 ... H6 with round cross sections.
  • the cavity resonators are arranged in the manner of the densest cylinder packing, each cavity resonating with its side wall adjoining the side walls of several other cavity resonators.
  • This constellation of the cavity resonators H1 ... H6 results in the greatest possible number of mutual side wall contacts.
  • Coupling openings e.g. holes, slots
  • FIG. 1 shows a slightly modified constellation of the cavity resonators H1 ... H6 compared to the embodiment shown in FIG. 2.
  • the arrangement of the cavity resonators in the manner of the densest cylinder packing allows a large number of variations in the composition of the cavity resonators to be coupled together.
  • a microwave filter which is constructed in accordance with the type described, can be expanded with little effort to include additional cavity resonators to form a more complex filter structure.
  • the above-mentioned secondary couplings between adjacent cavity resonators, but not consecutive in the energy flow direction, can be implemented either as positive or as negative couplings.
  • 3 is intended to illustrate how two adjacent cavity resonators can be coupled either positively or negatively.
  • the TE 011 wave mode exists in one of the two adjacent cavity resonators, of which FIG. 3 shows a longitudinal section parallel to the wave propagation direction z
  • the TE 012 wave mode exists in the other cavity resonator.
  • the magnetic field lines of the TE 011 and TE 012 wave modes are parallel to each other in the same direction.
  • a coupling opening K1 arranged there enables a positive coupling between the cavity resonators.
  • the magnetic field lines of the TE 011 and TE 012 wave modes run in opposite directions.
  • a coupling opening K2 there in the side wall enables negative coupling.

Landscapes

  • Control Of Motors That Do Not Use Commutators (AREA)

Abstract

Bei einem Mikrowellenfilter, das mehrere Hohlraumresonatoren (H1 ... H6) besitzt, die über Koppelöffnungen in ihren parallel zur Wellenausbreitungsrichtung verlaufenden Seitenwandungen miteinander gekoppelt sind, daß alle das Filter bildenden Hohlraumresonatoren nach Art einer dichtesten Zylinderpackung angeordnet sind, so daß jeder einzelne Hohlraumresonator mit einer größtmöglichen Zahl der vorhandenen Hohlraumresonatoren in Berührung steht und jeder Hohlraumresonator mit jedem seiner benachbarten Hohlraumresonatoren in den Seitenwandungs-Berührungszonen gekoppelt werden kann (Fig. 1).In the case of a microwave filter which has a plurality of cavity resonators (H1 ... H6) which are coupled to one another via coupling openings in their side walls running parallel to the direction of wave propagation, that all the cavity resonators forming the filter are arranged in the manner of a densest cylinder packing, so that each individual cavity resonator is included the largest possible number of existing cavity resonators is in contact and each cavity resonator can be coupled to each of its adjacent cavity resonators in the side wall contact zones (FIG. 1).

Description

Die vorliegende Erfindung betrifft ein Mikrowellenfilter, das mehrere Hohlraumresonatoren besitzt, die über Koppel­öffnungen in ihren parallel zur Wellenausbreitungsrich­tung verlaufenden Seitenwandungen miteinander gekoppelt sind.The present invention relates to a microwave filter which has a plurality of cavity resonators which are coupled to one another via coupling openings in their side walls running parallel to the direction of wave propagation.

Ein derartiges Mikrowellenfilter ist aus der DE-OS 26 43 094 bekannt. Bei diesem Mikrowellenfilter sind alle miteinander gekoppelten zylindrischen Hohlraumresonatoren im TE 011 Wel­lenmode betrieben, um eine möglichst hohe Filtergüte zu er­reichen. Die Hohlraumresonatoren des bekannten Mikrowellen­filters sind in einer recht komplizierten Konstellation zu­sammengefügt, damit zur Erzielung einer elliptischen Filter­charakteristik neben den Kopplungen der in Energieflußrich­tung aneinandergereihten Hohlraumresonatoren zusätzlich noch positive oder negative Überkopplungen zwischen anderen Hohl­raumresonatoren realisiert werden können.Such a microwave filter is known from DE-OS 26 43 094. With this microwave filter, all coupled cylindrical cavity resonators are operated in TE 011 wave mode in order to achieve the highest possible filter quality. The cavity resonators of the known microwave filter are assembled in a rather complicated constellation, so that in order to achieve an elliptical filter characteristic, in addition to the couplings of the cavity resonators lined up in the energy flow direction, positive or negative overcouplings between other cavity resonators can also be realized.

Der Erfindung liegt nun die Aufgabe zugrunde, ein Mikrowel­lenfilter der eingangs genannten Art anzugeben, das aus ei­ner einfachen, platzsparenden Hohlraumresonator-Konstruk­tion besteht, die eine möglichst große Vielzahl von Kopplun­gen zwischen den einzelnen Hohlraumresonatoren zuläßt.The invention is based on the object of specifying a microwave filter of the type mentioned at the outset, which consists of a simple, space-saving cavity construction which allows a large number of couplings between the individual cavity resonators.

Erfindungsgemäß wird diese Aufgabe durch die im Kennzeichen des Anspruchs 1 angegebenen Merkmale gelöst.According to the invention, this object is achieved by the features specified in the characterizing part of claim 1.

Zweckmäßige Ausführungen der Erfindung gehen aus den Unter­ansprüchen hervor.Appropriate embodiments of the invention emerge from the subclaims.

Durch die Anordnung der Hohlraumresonatoren nach Art einer dichtesten Zylinderpackung gibt es eine größtmögliche Zahl von Berührungszonen, die für Kopplungen ausnutzbar sind. Außerdem führt die Hohlraumresonatorkonstellation nach der /erfindung zu einem raumsparenden kompakten Mikrowellenfil­ter.Due to the arrangement of the cavity resonators in the manner of the densest cylinder packing, there is the greatest possible number of contact zones that can be used for couplings. In addition, the cavity resonator constellation according to the invention leads to a space-saving, compact microwave filter.

An Hand von in der Zeichnung dargestellten Ausführungsbei­spielen wird nachfolgend die Erfindung näher beschrieben.

  • Fig. 1 und 2 zeigen zwei verschiedene Konstellationen von Hohlraumresonatoren und
  • Fig. 3 zeigt Wellenmoden, die in den Hohlraumresona­toren existieren.
The invention is described in more detail below on the basis of exemplary embodiments shown in the drawing.
  • 1 and 2 show two different constellations of cavity resonators and
  • Fig. 3 shows wave modes that exist in the cavity resonators.

Der Fig. 1 ist ein Mikrowellenfilter zu entnehmen, das aus sechs zylindrischen Hohlraumresonatoren H1 ... H6 mit run­den Querschnitten besteht. Die Hohlraumresonatoren sind nach Art einer dichtesten Zylinderpackung angeordnet, wo­bei jeder Hohlraumresonator mit seiner Seitenwand an die Seitenwände mehrerer anderer Hohlraumresonatoren angrenzt. Durch diese Konstellation der Hohlraumresonatoren H1 ... H6 entsteht eine größtmögliche Zahl von gegenseitigen Seiten­wandungs-Berührungen. Über Koppelöffnungen (z.B. Löcher, Schlitze) in den Seitenwandungs-Berührungszonen kann nun eine Vielzahl von elektromagnetischen Kopplungen zwischen benachbarten Hohlraumresonatoren realisiert werden.1 shows a microwave filter which consists of six cylindrical cavity resonators H1 ... H6 with round cross sections. The cavity resonators are arranged in the manner of the densest cylinder packing, each cavity resonating with its side wall adjoining the side walls of several other cavity resonators. This constellation of the cavity resonators H1 ... H6 results in the greatest possible number of mutual side wall contacts. Coupling openings (e.g. holes, slots) in the side wall contact zones can now be used to implement a large number of electromagnetic couplings between adjacent cavity resonators.

Beim in Fig. 1 dargestellten Ausführungsbeispiel bestehen Kopplungen (mit dem Symbol gekennzeichnet in den Sei­tenwandungs-Berührungszonen zwischen den in Energiefluß­richtung angeordneten Hohlraumresonatoren H1 ... H6, be­ginnend mit dem einen Signaleingang E aufweisenden Hohl­ raumresonator H6. Außer diesen Haptkopplungen der in Ener­gieflußrichtung aneinandergereihten Hohlraumresonatoren gibt es zusätzlich noch Nebenkopplungen (mit dem Symbol x gekennzeichnet) zwischen dem zentralen Hohlraumresonator H1 und den ihm benachbarten Hohlraumresonatoren H3, H4, H5 und H6.In the embodiment shown in FIG. 1 there are couplings (marked with the symbol in the side wall contact zones between the cavity resonators H1 ... H6 arranged in the energy flow direction, starting with the cavity having a signal input E. room resonator H6. In addition to these haptic couplings of the cavity resonators lined up in the energy flow direction, there are also additional couplings (marked with the symbol x) between the central cavity resonator H1 and the cavity resonators H3, H4, H5 and H6 adjacent to it.

Eine gegenüber dem in Fig. 1 dargestellten Ausführungsbei­spiel leicht abgewandelte Konstellation der Hohlraumreso­natoren H1 ... H6 zeigt die Fig. 2. Hier sind Nebenkopplun­gen zwischen einem zentral angeordneten Hohlraumresonator H4 und dessen nicht in Energieflußrichtung benachbarten Hohlraumresonatoren H1, H2 und H6 und eine Nebenkopplung zwischen dem Signaleingangs-Hohlraumresonator H1 und dem Signalausgangs-Hohlraumresonator H6 eingerichtet.1 shows a slightly modified constellation of the cavity resonators H1 ... H6 compared to the embodiment shown in FIG. 2. Here there are secondary couplings between a centrally arranged cavity resonator H4 and its cavity resonators H1, H2 and H6, which are not adjacent in the energy flow direction, and a secondary coupling between the signal input cavity H1 and the signal output cavity H6.

Die Anordnung der Hohlraumresonatoren nach Art einer dich­testen Zylinderpackung läßt eine große Vielzahl von Varia­tionen bei der Zusammenstellung der miteinander zu koppeln­den Hohlraumresonatoren zu. Außerdem kann ein Mikrowellen­filter, das nach der beschriebenen Art aufgebaut ist, mit wenig Aufwand um zusätzliche Hohlraumresonatoren zu einer komplexeren Filterstruktur erweitert werden.The arrangement of the cavity resonators in the manner of the densest cylinder packing allows a large number of variations in the composition of the cavity resonators to be coupled together. In addition, a microwave filter, which is constructed in accordance with the type described, can be expanded with little effort to include additional cavity resonators to form a more complex filter structure.

Die oben angesprochenen Nebenkopplungen zwischen benachbar­ten, aber nicht in Energieflußrichtung aufeinanderfolgenden Hohlraumresonatoren können entweder als positive oder als negative Kopplungen realisiert werden. An Hand der Fig. 3 soll verdeutlicht werden, wie zwei benachbarte Hohlraumre­sonatoren entweder positiv oder negativ gekoppelt werden können. Dazu ist in einem der beiden benachbarten Hohlraum­resonatoren, von denen die Fig. 3 einen Längsschnitt parallel zur Wellenausbreitungsrichtung z zeigt, der TE 011-Wellen­mode und in dem anderen Hohlraumresonator der TE 012-Wellen­mode existent. In einem Bereich der beiden mit ihren Seiten­wandungen aneinandergrenzenden Hohlraumresonatoren verlau­ fen die magnetischen Feldlinien des TE 011- und des TE 012-­Wellenmodes in gleiche Richtung parallel zueinander. Eine dort angeordnete Koppelöffnung K1 ermöglicht eine positive Kopplung zwischen den Hohlraumresonatoren. In einem anderen Bereich der beiden Hohlraumresonatoren verlaufen die magne­tischen Feldlinien des TE 011- und des TE 012-Wellenmodes in entgegengesetzte Richtungen. Eine dort in der Seitenwan­dung vorhandene Koppelöffnung K2 ermöglicht eine negative Kopplung.The above-mentioned secondary couplings between adjacent cavity resonators, but not consecutive in the energy flow direction, can be implemented either as positive or as negative couplings. 3 is intended to illustrate how two adjacent cavity resonators can be coupled either positively or negatively. For this purpose, the TE 011 wave mode exists in one of the two adjacent cavity resonators, of which FIG. 3 shows a longitudinal section parallel to the wave propagation direction z, and the TE 012 wave mode exists in the other cavity resonator. In a region of the two cavity resonators adjoining one another with their side walls, leave it blue The magnetic field lines of the TE 011 and TE 012 wave modes are parallel to each other in the same direction. A coupling opening K1 arranged there enables a positive coupling between the cavity resonators. In another area of the two cavity resonators, the magnetic field lines of the TE 011 and TE 012 wave modes run in opposite directions. A coupling opening K2 there in the side wall enables negative coupling.

Würde man z.B. ein Mikrowellenfilter gemäß Fig. 1 mit po­sitiven Hauptkopplungen der in Energieflußrichtung aneinan­dergereihten Hohlraumresonatoren H1 ... H6 und mit nega­tiven Nebenkopplungen zwischen den Hohlraumresonatoren H1, H4 und den Hohlraumresonatoren H1, H6 verwirklichen, so erhielte man eine elliptische Filtercharakteristik mit 2 Paar echten Nullstellen sechster Ordnung mit einer Filtergüte von 15.000 bei 12 GHz.Would you e.g. 1 with positive main couplings of the cavity resonators H1 ... H6 lined up in the energy flow direction and with negative secondary couplings between the cavity resonators H1, H4 and the cavity resonators H1, H6, this would give an elliptical filter characteristic with 2 pairs of real sixth order zeros with a filter quality of 15,000 at 12 GHz.

Claims (4)

1. Mikrowellenfilter, das mehrere Hohlraumresonatoren be­sitzt, die über Koppelöffnungen in ihren parallel zur Wellenausbreitungsrichtung verlaufenden Seitenwandun­gen miteinander gekoppelt sind, dadurch gekennzeichnet, daß alle das Filter bildenden Hohlraumresonatoren (H1 ... H6) nach Art einer dichtesten Zylinderpackung angeordnet sind, so daß jeder einzelne Hohlraumresona­tor mit einer größtmöglichen Zahl der vorhandenen Hohl­raumresonatoren in Berührung steht und jeder Hohlraum­resonator mit jedem seiner benachbarten Hohlraumresona­toren in den Seitenwandungs-Berührungszonen gekoppelt werden kann.1. Microwave filter, which has a plurality of cavity resonators which are coupled to one another via coupling openings in their side walls running parallel to the direction of wave propagation, characterized in that all the cavity resonators (H1 ... H6) forming the filter are arranged in the manner of a densest cylinder packing, so that each individual cavity resonates with the largest possible number of existing cavity resonators and each cavity resonator can be coupled to each of its adjacent cavity resonators in the side wall contact zones. 2. Mikrowellenfilter nach Anspruch 1, dadurch gekennzeich­net, daß in einem oder mehreren der Hohlraumresonatoren ein Wellenmode existiert, dessen Feldverlauf so orien­tiert ist, daß er mit einem in benachbarten Hohlraumre­sonatoren existierenden anderen Wellenmode entweder eine positive Kopplung eingeht, wenn die Kopplung (K1) an ei­ner Stelle in den sich berührenden Seitenwandungen er­folgt, wo die Feldlinien beider Wellenmoden in gleiche Richtung verlaufen, oder eine negative Kopplung eingeht, wenn die Kopplung (K2) an einer Stelle erfolgt, wo die Feldlinien der beiden Wellenmoden in entgegengesetzte Richtungen verlaufen.2. Microwave filter according to claim 1, characterized in that in one or more of the cavity resonators there is a wave mode, the field profile of which is oriented so that it enters into a positive coupling with an existing wave resonator in adjacent cavity either when the coupling (K1) is on a place in the touching side walls where the field lines of both wave modes run in the same direction, or a negative coupling occurs if the coupling (K2) takes place at a point where the field lines of the two wave modes run in opposite directions. 3. Mikrowellenfilter nach Anspruch 2, dadurch gekennzeich­net, daß der eine Wellenmode vom Typ TE 011 und der andere Wellenmode vom Typ TE 012 ist.3. Microwave filter according to claim 2, characterized in that the one wave mode of the type TE 011 and the other wave mode of the type TE 012. 4. Mikrowellenfilter nach einer der vorhergehenden Ansprüche, dadurch gekennzeichnet, daß alle in Energieflußrichtung zwischen einem Signaleingangs-Hohlraumresonator (H1) und einem Signalausgangs-Hohlraumresonator (H6) aufeinander­folgenden Hohlraumresonatoren (H2 ... H5) positiv mit­einander gekoppelt sind und daß zwischen benachbarten Hohlraumresonatoren, die nicht in Energieflußrichtung direkt aufeinanderfolgen, negative Kopplungen beste­hen.4. Microwave filter according to one of the preceding claims, characterized in that all in the energy flow direction between a signal input cavity (H1) and a signal output cavity (H6) successive cavity resonators (H2 ... H5) are positively coupled and that there are negative couplings between adjacent cavity resonators that do not follow each other directly in the energy flow direction.
EP87107534A 1986-06-25 1987-05-23 Microwave filter with multiple coupled cavity resonators Expired - Lifetime EP0250858B1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
DE3621298 1986-06-25
DE19863621298 DE3621298A1 (en) 1986-06-25 1986-06-25 MICROWAVE FILTER WITH MULTIPLE-COUPLED HOMELINE RESONATORS

Publications (3)

Publication Number Publication Date
EP0250858A2 true EP0250858A2 (en) 1988-01-07
EP0250858A3 EP0250858A3 (en) 1988-12-07
EP0250858B1 EP0250858B1 (en) 1993-07-14

Family

ID=6303681

Family Applications (1)

Application Number Title Priority Date Filing Date
EP87107534A Expired - Lifetime EP0250858B1 (en) 1986-06-25 1987-05-23 Microwave filter with multiple coupled cavity resonators

Country Status (4)

Country Link
US (1) US4772863A (en)
EP (1) EP0250858B1 (en)
CA (1) CA1271533A (en)
DE (2) DE3621298A1 (en)

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0752732A1 (en) * 1995-07-04 1997-01-08 Robert Bosch Gmbh Microwave filter

Families Citing this family (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19523220A1 (en) * 1995-06-27 1997-01-02 Bosch Gmbh Robert Microwave filter
FR2742262B1 (en) 1995-12-12 1998-01-09 Alcatel Telspace PSEUDO-ELLIPTICAL FILTER IN THE MILLIMETER FIELD CARRIED OUT IN WAVEGUIDE TECHNOLOGY
US5936490A (en) 1996-08-06 1999-08-10 K&L Microwave Inc. Bandpass filter
US6101300A (en) * 1997-06-09 2000-08-08 Massachusetts Institute Of Technology High efficiency channel drop filter with absorption induced on/off switching and modulation
US6130969A (en) * 1997-06-09 2000-10-10 Massachusetts Institute Of Technology High efficiency channel drop filter
SE510960C2 (en) * 1997-11-21 1999-07-12 Ericsson Telefon Ab L M waveguide
US6337610B1 (en) 1999-11-22 2002-01-08 Comsat Corporation Asymmetric response bandpass filter having resonators with minimum couplings
JP3839410B2 (en) * 2003-02-12 2006-11-01 Ｔｄｋ株式会社 Filter and resonator arrangement method
DE10361809A1 (en) * 2003-12-30 2005-07-28 Tesat-Spacecom Gmbh & Co. Kg Topology for dielectric filter e.g. for satellite communications, has resonators in rows with one row displaced from next row by half spacing of resonators
EP2043518A1 (en) 2006-07-21 2009-04-08 Anaxsys Technology Limited Gas sensor
AU2009235239A1 (en) 2008-04-10 2009-10-15 Anaxsys Technology Ltd Gas sensor

Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2285729A1 (en) * 1974-09-18 1976-04-16 Labo Cent Telecommunicat Linear phase microwave filter - using pairs of circular resonant cavities electrically coupled and supplied by rectangular waveguide
JPS5986902A (en) * 1982-11-10 1984-05-19 Mitsubishi Electric Corp Band pass filter

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3969692A (en) * 1975-09-24 1976-07-13 Communications Satellite Corporation (Comsat) Generalized waveguide bandpass filters
US4453146A (en) * 1982-09-27 1984-06-05 Ford Aerospace & Communications Corporation Dual-mode dielectric loaded cavity filter with nonadjacent mode couplings

Patent Citations (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
FR2285729A1 (en) * 1974-09-18 1976-04-16 Labo Cent Telecommunicat Linear phase microwave filter - using pairs of circular resonant cavities electrically coupled and supplied by rectangular waveguide
JPS5986902A (en) * 1982-11-10 1984-05-19 Mitsubishi Electric Corp Band pass filter

Non-Patent Citations (3)

* Cited by examiner, † Cited by third party
Title
1978 IEEE INTERNATIONAL SYMPOSIUM ON CIRCUITS AND SYSTEMS PROCEEDINGS, New York, 17.-19. Mai 1978, Seiten 790-793, IEEE, New York, US; K.A. ZAKI et al.: "Sensitivity analysis of multi-coupled cavity filters" *
IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, Band MTT-24, Nr. 10, Oktober 1976, Seiten 640-648; A.E. ATIA et al.: "General TE011-mode waveguide bandpass filters" *
PATENT ABSTRACTS OF JAPAN, Band 8, Nr. 198 (E-265)[1635], 11. September 1984; & JP-A-59 86 902 (MITSUBISHI DENKI K.K.) 19-05-1984 *

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0752732A1 (en) * 1995-07-04 1997-01-08 Robert Bosch Gmbh Microwave filter

Also Published As

Publication number Publication date
DE3786495D1 (en) 1993-08-19
EP0250858A3 (en) 1988-12-07
DE3621298A1 (en) 1988-01-07
US4772863A (en) 1988-09-20
EP0250858B1 (en) 1993-07-14
CA1271533A (en) 1990-07-10

Similar Documents

Publication Publication Date Title
EP0250858A2 (en) Microwave filter with multiple coupled cavity resonators
DE2801071A1 (en) CHAMBER FOR ATTENUATING SOUND ENERGY IN A CHANNEL THROUGH A GAS FLOW
DE2802795A1 (en) ACOUSTIC SURFACE WAVE RESONATOR
DE2643094A1 (en) GENERALIZED WAVE GUIDE BANDPASS FILTER
DE60011245T2 (en) HOLLOW FILTERS WITH ASYMMETRICALLY GROOVED RESONATORS
EP0751579B1 (en) Microwavefilter
EP0250857B1 (en) Microwave filter
DE2855285C2 (en)
DE10034338C2 (en) Multipole cascading quadruple bandpass filter based on dielectric dual-mode resonators
DE2640210C3 (en) Filter for very short electromagnetic waves
EP0525416B1 (en) Microwave filter
DE1942909A1 (en) Filter for very short electromagnetic waves
DE102019109638A1 (en) Control cabinet arrangement with a control cabinet frame and a multi-pole contact protection module mounted on a mounting plate
DE1942867A1 (en) Filter for very short electromagnetic waves
DE19623144A1 (en) Microwave filter, consisting of several coaxial resonators
DE2242535C3 (en) Filter for very short electromagnetic waves
DE19504396C2 (en) Housing for a resonator
DE4014541C2 (en)
DE2032597A1 (en) Microwave filter filter system
DE4014542C2 (en)
DE4116755A1 (en) Microwave filter providing mode coupling between non-adjacent cavities - saves vol. and wt. with fewer cavities for transfer of modes not corresp. to circuit resonances
DE4318593C2 (en) Cavity resonator
DE2738613B2 (en) Filter circuit consisting of concentrated switching elements for the range of meter and decimeter waves
EP1320193A2 (en) Resonator filter cascade
DE3445399A1 (en) Septum polarisation filter

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A2

Designated state(s): DE FR GB IT

PUAL Search report despatched

Free format text: ORIGINAL CODE: 0009013

AK Designated contracting states

Kind code of ref document: A3

Designated state(s): DE FR GB IT

17P Request for examination filed

Effective date: 19890118

17Q First examination report despatched

Effective date: 19910903

GRAA (expected) grant

Free format text: ORIGINAL CODE: 0009210

AK Designated contracting states

Kind code of ref document: B1

Designated state(s): DE FR GB IT

ITF It: translation for a ep patent filed

Owner name: BARZANO' E ZANARDO MILANO S.P.A.

GBT Gb: translation of ep patent filed (gb section 77(6)(a)/1977)

Effective date: 19930713

REF Corresponds to:

Ref document number: 3786495

Country of ref document: DE

Date of ref document: 19930819

ET Fr: translation filed
PLBE No opposition filed within time limit

Free format text: ORIGINAL CODE: 0009261

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: NO OPPOSITION FILED WITHIN TIME LIMIT

26N No opposition filed
PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: DE

Payment date: 19940915

Year of fee payment: 8

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: GB

Payment date: 19950426

Year of fee payment: 9

PGFP Annual fee paid to national office [announced via postgrant information from national office to epo]

Ref country code: FR

Payment date: 19950512

Year of fee payment: 9

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: DE

Effective date: 19960201

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: GB

Effective date: 19960523

GBPC Gb: european patent ceased through non-payment of renewal fee

Effective date: 19960523

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: FR

Effective date: 19970131

REG Reference to a national code

Ref country code: FR

Ref legal event code: ST

PG25 Lapsed in a contracting state [announced via postgrant information from national office to epo]

Ref country code: IT

Free format text: LAPSE BECAUSE OF NON-PAYMENT OF DUE FEES

Effective date: 20050523