EP1791212B1 - Mikrowellenfilter mit einem Kapazitivkopplungselement - Google Patents

Mikrowellenfilter mit einem Kapazitivkopplungselement Download PDF

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Publication number
EP1791212B1
EP1791212B1 EP20050025887 EP05025887A EP1791212B1 EP 1791212 B1 EP1791212 B1 EP 1791212B1 EP 20050025887 EP20050025887 EP 20050025887 EP 05025887 A EP05025887 A EP 05025887A EP 1791212 B1 EP1791212 B1 EP 1791212B1
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EP
European Patent Office
Prior art keywords
opening
coupling element
bore
resonators
cylindrical body
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Not-in-force
Application number
EP20050025887
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English (en)
French (fr)
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EP1791212A1 (de
Inventor
Ramon Sobrido
Stefan Burger
Michael Höft
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.)
Panasonic Corp
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Panasonic Corp
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Publication date
Application filed by Panasonic Corp filed Critical Panasonic Corp
Priority to EP20050025887 priority Critical patent/EP1791212B1/de
Priority to DE200560015461 priority patent/DE602005015461D1/de
Publication of EP1791212A1 publication Critical patent/EP1791212A1/de
Application granted granted Critical
Publication of EP1791212B1 publication Critical patent/EP1791212B1/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
    • H01P1/201—Filters for transverse electromagnetic waves
    • H01P1/205—Comb or interdigital filters; Cascaded coaxial cavities
    • H01P1/2053—Comb or interdigital filters; Cascaded coaxial cavities the coaxial cavity resonators being disposed parall to each other

Definitions

  • the present invention relates to a microwave filter comprising a plurality of coaxial resonators, at least two adjacent coaxial resonators being electrically coupled by a capacitive coupling element having an elongated portion and, at each end thereof, an enlarged diameter portion, the elongated portion being held by a dielectric mounting element which is placed in an opening cut out from an end of the wall separating the cavities of the two resonators, the elongated portion of the capacitive coupling element projecting into both cavities, wherein the dielectric mounting has a bore for holding at least part of the elongated portion of the coupling element, wherein the dielectric mounting, with the coupling element inserted into the bore, is received in the coupling opening which is of complementary shape to the dielectric mounting to engage the latter along its length in a press-fitting manner between two opposing side walls of the coupling opening.
  • the microwave region of the electromagnetic spectrum finds widespread use in various fields of technology. Exemplary applications include wireless communication systems, such as mobile communication and satellite communication systems, as well as navigation and radar technology.
  • the growing number of microwave applications increases the possibility of interference occurring within a system or between different systems. Therefore, the microwave region is divided into a plurality of distinct frequency bands.
  • microwave filters are utilized to perform band-pass and band reject functions during transmission and/or reception. Accordingly, the filters are used to separate the different frequency bands and to discriminate between wanted and unwanted signal frequencies so that the quality of the received and of the transmitted signals is largely governed by the characteristics of the filters. Commonly, the filters have to provide for a small bandwidth and a high filter quality.
  • microwave filters include a plurality of resonators which are coupled together in various configurations.
  • Each resonator usually comprises a space contained within a closed or substantially closed conducting surface. Upon suitable external excitation, an oscillating electromagnetic field may be maintained within this space or cavity.
  • the resonators exhibit marked resonance effects and are characterized by the respective resonant frequency and band-width.
  • coaxial resonator One particular type of resonator regularly used to build microwave filters is known as coaxial resonator.
  • This resonator structure is short-circuited at one end and open circuited at the other end, i.e. comprises a housing defining a cavity and having a longitudinal axis, and a coaxial inner conductor electrically connected to the housing at only one end.
  • the housing comprises a base, from which the inner conductor extends upwardly, and a side wall extending upwardly from the base, and in a certain distance above the open end of the inner conductor, the housing is enclosed by a cover so that a gap exists between one end of the inner conductor and the inner surface of the cover.
  • Such coaxial resonators are also referred to as combline resonators, and can essentially be regarded as a section of coaxial transmission line that is short-circuited at one end and capacitively loaded (open) at the other end.
  • Microwave energy may be coupled into the cavity by a magnetic loop antenna located near the inner conductor at the short-circuited end of the transmission line.
  • the free space between the top of the inner conductor and the cover is referred to as the capacitive gap.
  • the easiest way to achieve coupling between the resonators is the provision of a larger aperture in the wall between adjacent resonators which leads to magnetic coupling between these resonators. Therefore, the main way of coupling between the resonators is preferably realized as magnetic coupling. Nevertheless, there are also applications in which besides magnetic coupling also electric coupling is helpful. Such cross-coupling is helpful for improvement of the filter characteristic.
  • the required electric coupling between two coaxial resonators is achieved by provision of a capacitive coupling element which may comprise an elongated portion or pin.
  • the coupling element is held in a dielectric mounting to avoid contact with the conductive walls of the cavities.
  • the mounting is placed in an opening cut out from an end of the side wall separating the two adjacent resonators.
  • the elongated portion or pin extends into both cavities and provides an electric coupling.
  • Such arrangement is for example described in EP 0 525 416 B1 .
  • the coupling element is provided with enlarged diameter end portions or disks at both ends of the elongated pin portion.
  • Such coupling elements are for example disclosed in DE 21 61 792 A1 on which the preamble of claim 1 is based.
  • Document DE 26 40 210 A1 discloses a microwave filter comprising the feature of the preamble of claim 1.
  • the dielectric mounting is of essentially cubic shape with a groove on each side wall, each groove being shaped for receiving one of the two side walls of the coupling opening. In this manner the dielectric mounting is held in a fixed orientation in the coupling opening in engagement with its side walls.
  • the dielectric mounting of the coupling element is a cylindrical body formed in one piece of elastic material, the bore being perpendicular to its longitudinal axis.
  • the cylindrical body has a cut leading from one of its end faces to the bore and merging with the bore.
  • the elongated portion of the coupling member may be pressed into and slid through the cut.
  • the cut is enlarged to a gap by elastic deformation of the cylindrical body.
  • the cylindrical mounting body with the coupling element inserted into the bore, is received in the coupling opening in the side wall separating the two resonators to be coupled.
  • This coupling opening is of complementary shape to the cylindrical body so that it may receive the cylindrical body in a press'-fitting manner.
  • the opposing surfaces of the cut-out opening in the side wall thus have the shape of cylinder surface segments.
  • the cylindrical body is closely fitting into this cylinder segment opening. Due to the press-fit of the cylindrical body in the cylinder segment opening, the opposing portions of the cylinder adjacent to the cut are pressed together so that the coupling element is secured in the bore.
  • the cover of the microwave filter which covers the resonator cavities has an opening in the area in which the free end face of the cylindrical body in the coupling opening is situated. This allows to engage the cylindrical body, while the cover of the microwave filter is in its closed stage, and to vary capacitive coupling strength by slightly turning the cylindrical body in its seat as described above.
  • the cylindrical mounting body may for example be made of PTFE (polytetrafluor ethylene), polyethylene, FEP (fluorinated ethylene-propylene), or PEEK (polyether etherketone).
  • the mounting body is simple to manufacture, because it may be cut from a rod to the desired length, whereafter the bore is formed and a cut is applied running from one of the end faces to the bore.
  • Figure 1 shows a perspective view of a portion of a microwave filter comprising a plurality of coaxial resonators, one of the resonator cavities being indicated by 1 and its inner conductor by 2.
  • Each resonator comprises an essentially circular cavity.
  • the main couplings between the coaxial resonators are achieved by large apertures 3 or cut-outs in the side walls between adjacent cavities.
  • the electric coupling arrangement of the microwave filter of the present invention is achieved by a cylindrical mounting body 7 which has a bore 9 through the cylinder body extending perpendicular to the cylinder axis. This bore 9 is dimensioned to receive the elongated or pin portion 5 of a capacitive coupling element 6.
  • the cylindrical mounting body 7 further has a cut 8 which leads from one of its end faces and merges into the bore 9. This allows that, by stretching away the two cylinder portions separated by the cut, a gap is formed which is sufficiently large to allow the pin portion 5 of the coupling element 6 to be slid through the cut 8 into the bore 9, whereafter the elastic deformation forming the gap is released and the cut is closed.
  • the mounting body 7 with the inserted coupling element 6 is fitted into the coupling opening 10 which is cut out from the upper end of the side wall separating the adjacent cavities to be coupled.
  • the opposing surfaces of the cut-out in the side walls are adapted to conform to the surface of the cylindrical mounting body 7 and are dimensioned to receive this cylindrical mounting body 7 in a press fitting manner. This ensures that the capacitive coupling element 6 is securely held in place once the mounting is in its press-fitting seat in the coupling opening 10.
  • This state is shown in Figure 2 .
  • the cylindrical shape of the mounting body 7 together with the cylinder segment shape of the opposing surfaces of the opening 10 with complementary shape provides for a press-fitting seat of the mounting body 7. Nevertheless, it is possible to turn the mounting body 7 inside the opening 10 in order to alter the direction of the coupling element 6. Since this also alters the locations of the enlarged diameter coupling disks 4, the capacitive coupling strength may be altered. This can also be achieved if the cover (not shown) is already closed and fixed, if an opening is provided in the cover in the area over the mounting body 7.
  • a further advantage of the cylindrical mounting body 7 is that it can be received in openings which are formed in side walls of different thicknesses.
  • a side wall of greater thickness a larger part of the cylinder surface is surrounded by the opposing surfaces of the opening in the side wall, whereas in thinner side walls only a relatively small part of the cylinder surface is engaged by the opposing surfaces of the opening, whereas the radius of curvature of the opposing surfaces of the opening in the side wall is always the same and equal to the radius of the cylinder.

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  • Physics & Mathematics (AREA)
  • Electromagnetism (AREA)
  • Control Of Motors That Do Not Use Commutators (AREA)

Claims (3)

  1. Mikrowellenfilter mit einer Mehrzahl von Koaxialresonatoren, wobei wenigstens zwei benachbarte Koaxialresonatoren durch ein kapazitives Kopplungselement (6) elektrisch gekoppelt sind, das einen länglichen Bereich (5) und an jedem seiner Enden einen Endbereich (4) mit vergrößertem Durchmesser aufweist, wobei der längliche Bereich von einem dielektrischen Träger (7) gehalten wird, der in einer Kopplungsöffnung (10) platziert ist, die von einem Ende aus aus einer die Hohlräume der beiden Resonatoren trennenden Seitenwand herausgeschnitten ist, wobei der längliche Bereich des kapazitiven Kopplungselements in beide Hohlräume hinein vorsteht, wobei der dielektrische Träger eine Bohrung (9) zum Halten wenigstens eines Teils des länglichen Bereichs (5) des Kopplungselements (6) aufweist, wobei der dielektrische Träger (7) mit dem in die Bohrung (9) eingesetzten Kopplungselement (6) in der Kopplungsöffnung (10) aufgenommen ist, die eine zu dem dielektrischen Träger komplementäre Form hat, um den letzteren entlang seiner Länge im Presssitz zwischen den beiden gegenüberliegenden Seitenwänden der Kopplungsöffnung einzufassen, dadurch gekennzeichnet, dass der dielektrische Träger (7) ein Stück Kunststoffmaterial mit einer zylindrischen Körperform ist, wobei die Bohrung (9) senkrecht zur Zylinderachse liegt, und dass der zylindrische Körper einen Einschnitt (8) hat, der von seiner Endflächen zu der Bohrung führt und sich in die Bohrung (9) öffnet, wobei der längliche Bereich durch den Einschnitt (8) in die Bohrung (9) eingeführt ist.
  2. Mikrowellenfilter nach Anspruch 1, dadurch gekennzeichnet, dass der die Resonatoren abdeckende Deckel in dem Bereich der Öffnung (10) zwischen den beiden elektrisch gekoppelten Resonatoren eine Öffnung hat, die es ermöglicht, an der Endfläche des zylindrischen Körpers (7) anzugreifen, um den zylindrischen Körper in seinem Sitz in der Öffnung um seine Längsachse zu drehen, um dadurch die von dem kapazitiven Kopplungselement bewirkte kapazitive Kopplungsstärke zu modifizieren.
  3. Mikrowellenfilter nach Anspruch 1 oder 2, dadurch gekennzeichnet, dass der zylindrische Körper aus einem elastischen Material hergestellt ist, das aus der Gruppe bestehend aus PTFE (Polytetrafluorethylen), Polyethylen, FEP (Fluorethylenpropylen), PEEK (Polyehteretherketon) ausgewählt ist.
EP20050025887 2005-11-28 2005-11-28 Mikrowellenfilter mit einem Kapazitivkopplungselement Not-in-force EP1791212B1 (de)

Priority Applications (2)

Application Number Priority Date Filing Date Title
EP20050025887 EP1791212B1 (de) 2005-11-28 2005-11-28 Mikrowellenfilter mit einem Kapazitivkopplungselement
DE200560015461 DE602005015461D1 (de) 2005-11-28 2005-11-28 Mikrowellenfilter mit einem Kapazitivkopplungselement

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
EP20050025887 EP1791212B1 (de) 2005-11-28 2005-11-28 Mikrowellenfilter mit einem Kapazitivkopplungselement

Publications (2)

Publication Number Publication Date
EP1791212A1 EP1791212A1 (de) 2007-05-30
EP1791212B1 true EP1791212B1 (de) 2009-07-15

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DE (1) DE602005015461D1 (de)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102460825A (zh) * 2009-06-18 2012-05-16 Ace技术株式会社 交叉耦合调节装置以及包括该装置的rf腔体滤波器
CN104078730A (zh) * 2013-03-29 2014-10-01 国基电子（上海）有限公司 空腔滤波器

Families Citing this family (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2229707A4 (de) * 2007-12-13 2011-01-19 Triasx Pty Ltd Mikrowellenfilter
EP2421085A1 (de) * 2010-08-19 2012-02-22 Alcatel Lucent Filter für Funkfrequenzsignale
EP2429026B1 (de) * 2010-09-10 2018-11-28 Alcatel Lucent Filter für Funkfrequenzsignale
CN103296359B (zh) * 2012-02-29 2017-05-24 深圳光启创新技术有限公司 一种滤波器
EP3079200B1 (de) 2013-12-30 2019-04-24 Huawei Technologies Co., Ltd. Resonator, filter, duplexer, multiplexer und kommunikationsvorrichtung
CN108550964B (zh) * 2018-05-09 2024-04-16 广东通宇通讯股份有限公司 一种基于容性交叉耦合飞杆的陶瓷介质波导滤波器
WO2022019041A1 (ja) * 2020-07-22 2022-01-27 株式会社村田製作所 バンドパスフィルタおよびそれを備える高周波フロントエンド回路

Family Cites Families (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2640210C3 (de) * 1976-09-07 1979-05-03 Siemens Ag, 1000 Berlin Und 8000 Muenchen Filter für sehr kurze elektromagnetische Wellen
US4453146A (en) * 1982-09-27 1984-06-05 Ford Aerospace & Communications Corporation Dual-mode dielectric loaded cavity filter with nonadjacent mode couplings
JPH0750842B2 (ja) * 1988-06-02 1995-05-31 日本電気株式会社 高周波結合器
EP0525416B1 (de) 1991-07-29 1995-10-18 ANT Nachrichtentechnik GmbH Mikrowellenfilter
US5608363A (en) * 1994-04-01 1997-03-04 Com Dev Ltd. Folded single mode dielectric resonator filter with cross couplings between non-sequential adjacent resonators and cross diagonal couplings between non-sequential contiguous resonators
IL112465A0 (en) 1995-01-27 1996-01-31 Israel State Microwave band pass filter

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102460825A (zh) * 2009-06-18 2012-05-16 Ace技术株式会社 交叉耦合调节装置以及包括该装置的rf腔体滤波器
CN102460825B (zh) * 2009-06-18 2014-07-23 Ace技术株式会社 交叉耦合调节装置以及包括该装置的rf腔体滤波器
CN104078730A (zh) * 2013-03-29 2014-10-01 国基电子（上海）有限公司 空腔滤波器
CN104078730B (zh) * 2013-03-29 2017-04-26 国基电子（上海）有限公司 空腔滤波器

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Publication number Publication date
DE602005015461D1 (de) 2009-08-27
EP1791212A1 (de) 2007-05-30

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