EP0250857B1 - Microwave filter - Google Patents
Microwave filter Download PDFInfo
- Publication number
- EP0250857B1 EP0250857B1 EP87107533A EP87107533A EP0250857B1 EP 0250857 B1 EP0250857 B1 EP 0250857B1 EP 87107533 A EP87107533 A EP 87107533A EP 87107533 A EP87107533 A EP 87107533A EP 0250857 B1 EP0250857 B1 EP 0250857B1
- Authority
- EP
- European Patent Office
- Prior art keywords
- mode
- cavity
- coupling
- cavity resonator
- coupled
- 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 - Lifetime
Links
- 230000008878 coupling Effects 0.000 claims description 36
- 238000010168 coupling process Methods 0.000 claims description 36
- 238000005859 coupling reaction Methods 0.000 claims description 36
- 230000010287 polarization Effects 0.000 description 3
- 238000000034 method Methods 0.000 description 2
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
- H01P1/2082—Cascaded cavities; Cascaded resonators inside a hollow waveguide structure with multimode resonators
Definitions
- the present invention relates to a microwave filter, consisting of at least two cavity resonators, in each of which at least one TE or TM wave mode exists, with a coupling between the wave modes of both cavity resonators taking place via a coupling aperture present between two adjacent cavity resonators.
- Such a microwave filter is known, for example, from DE-PS 21 22 337 or the IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. MIT-32, No. 11, Nov. 1984, pp. 1449-1454.
- the resonance circuits of the microwave filters on which this is based are realized by TE and / or TM wave modes which resonate in the individual cavity resonators.
- the characteristic of such a microwave filter depends on which orthogonally polarized wave modes exist in the individual cavity resonators and which of these wave modes are coupled to one another. Couplings between the wave modes existing in each individual cavity resonator and couplings between wave modes in different cavity resonators come into question. Cross-cavity resonance wave mode couplings take place via coupling apertures with coupling openings therein.
- the invention is based on the object of specifying a microwave filter of the type mentioned at the outset which, compared to the prior art, offers further possibilities for realizing filter characteristics.
- the microwave filter shown in FIG. 1 consists of two cylindrical cavity resonators HR1 and HR2, of which the first cavity resonator HR1 has an input E for coupling in a microwave signal and the second cavity resonator HR2 has an output A for coupling out a signal.
- the various known possibilities of coupling and decoupling microwave signals will not be discussed in more detail here.
- the direction of the E field lines of the TE11n wave mode shown in FIG. 2b corresponds to its direction of polarization.
- Fig. 2a shows the TMO1p wave mode. Its E field lines run in the direction of wave propagation, the direction of polarization (see arrow R5) of this TMO1p wave mode.
- each individual cavity resonator can be formed by discontinuity coupling elements, e.g. Tuning screws, which are embedded in the cavity wall in a known manner, are coupled.
- Couplings of the wave modes of one cavity resonator HR1 with wave modes of the other cavity resonator HR2 take place via a coupling diaphragm KB arranged between the two adjacent cavity resonators.
- a slot-shaped coupling opening K1 is arranged off-center in the coupling aperture KB. This coupling opening is located at a point where the magnetic field lines or components of the TE11n wave mode of the resonance circuit R1 in the first cavity HR1 and the magnetic field lines of the TMO1p wave mode of the resonance circuit R5 in the second cavity HR2 run parallel to one another. Thus, these two wave modes are coupled via the coupling opening K1.
- the TE11n wave mode of the resonance circuit R1 of the first cavity resonator HR1 is also polarized with the same TE11n wave mode of the resonant circuit R4 coupled in the second cavity HR2.
- a coupling between the TE11n wave mode of the resonance circuit R2 in the first cavity resonator HR1 and the TMO1p wave mode of the resonance circuit R5 and also the TE11n -Wave mode of the resonant circuit R3 in the second cavity HR2 can be effected.
- a very simple coupling opening structure can be used to achieve a large number of couplings between differently designed or differently polarized wave modes of adjacent cavity resonators.
- the choice of the dimensioning and the position of the coupling opening determine the frequency at which a wave mode coupling takes place and the degree of coupling.
- the microwave filter consisted of only two cavity resonators.
- filters can also be constructed from more than just two cavity resonators, with one (single-mode) two (dual-mode) or three wave modes (triple-mode) existing in each individual cavity resonator, which can be coupled to one another depending on the desired filter characteristic.
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Description
Die vorliegende Erfindung betrifft ein Mikrowellenfilter, bestehend aus mindestens zwei Hohlraumresonatoren, in denen jeweils mindestens ein TE- oder TM-Wellenmode existiert, wobei über eine zwischen zwei benachbarten Hohlraumresonatoren vorhandene Koppelblende eine Kopplung zwischen den Wellenmoden beider Hohlraumresonatoren erfolgt.The present invention relates to a microwave filter, consisting of at least two cavity resonators, in each of which at least one TE or TM wave mode exists, with a coupling between the wave modes of both cavity resonators taking place via a coupling aperture present between two adjacent cavity resonators.
Ein derartiges Mikrowellenfilter ist z.B. aus der DE-PS 21 22 337 oder der IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. MIT-32, No. 11, Nov. 1984, S. 1449-1454 bekannt. Die Resonanzkreise der hier zugrunde liegenden Mikrowellenfilter sind durch TE- und/oder TM-Wellenmoden realisiert, die in den einzelnen Hohlraumresonatoren in Resonanz schwingen. Die Charakteristik eines solchen Mikrowellenfilters hängt davon ab, welche orthogonal zueinander polarisierten Wellenmoden in den einzelnen Hohlraumresonatoren existieren und welche dieser Wellenmoden miteinander gekoppelt sind. Dabei kommen Kopplungen zwischen den in jedem einzelnen Hohlraumresonatoren existierenden Wellenmoden und Kopplungen zwischen Wellenmoden in verschiedenen Hohlraumresonatoren in Frage. Hohlraumresonator übergreifende Wellenmode-Kopplungen erfolgen über Koppelblenden mit darin vorhandenen Koppelöffnungen.Such a microwave filter is known, for example, from DE-PS 21 22 337 or the IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, VOL. MIT-32, No. 11, Nov. 1984, pp. 1449-1454. The resonance circuits of the microwave filters on which this is based are realized by TE and / or TM wave modes which resonate in the individual cavity resonators. The characteristic of such a microwave filter depends on which orthogonally polarized wave modes exist in the individual cavity resonators and which of these wave modes are coupled to one another. Couplings between the wave modes existing in each individual cavity resonator and couplings between wave modes in different cavity resonators come into question. Cross-cavity resonance wave mode couplings take place via coupling apertures with coupling openings therein.
Die Erfindung geht von der Aufgabe aus, ein Mikrowellenfilter der eingangs genannten Art anzugeben, das gegenüber dem Stand der Technik weitere Möglichkeiten bietet zur Realisierung von Filtercharakteristika.The invention is based on the object of specifying a microwave filter of the type mentioned at the outset which, compared to the prior art, offers further possibilities for realizing filter characteristics.
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.
Bei den aus der DE-PS 21 22 337 bzw. aus der IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES hervorgehenden Mikrowellenfiltern finden Hohlraumresonator übergreifende Kopplungen nur zwischen gleichpolarisierten TE-Wellenmoden bzw. zwischen gleichpolarisierten TM-Wellenmoden statt. Eine Vielzahl weiterer Filtercharakteristika läßt sich realisieren, wenn wie beim Anmeldungsgegenstand auch TM-Wellenmoden in einem Hohlraumresonator mit TE-Wellenmoden eines anderen Hohlraumresonators gekoppelt werden.In the case of the microwave filters resulting from DE-PS 21 22 337 or from the IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, cross-cavity resonance couplings only take place between equally polarized TE wave modes or between equally polarized TM wave modes. A large number of further filter characteristics can be realized if, as in the subject of the application, TM wave modes in one cavity resonator are coupled with TE wave modes of another cavity resonator.
An Hand eines in der Zeichnung dargestellten Ausführungsbeispiels soll nun die Erfindung näher erläutert werden.
- Fig 1
- zeigt ein Mikrowellenfilter mit zwei Hohlraumresonatoren und
- Fig. 2a, 2b
- zeigen einen TMO1p- und einen TE11n-Wellenmode.
- Fig. 1
- shows a microwave filter with two resonators and
- 2a, 2b
- show a TMO1p and a TE11n wave mode.
Das in Fig. 1 dargestellte Mikrowellenfilter besteht aus zwei zylindrischen Hohlraumresonatoren HR1 und HR2, von denen der erste Hohlraumresonator HR1 einen Eingang E zum Einkoppeln eines Mikrowellensignals und der zweite Hohlraumresonator HR2 einen Ausgang A zum Auskoppeln eines Signals besitzt. Auf die verschiedensten bekannten Möglichkeiten, Mikrowellensignale ein- und auszukoppeln, soll hier nicht näher eingegangen werden.The microwave filter shown in FIG. 1 consists of two cylindrical cavity resonators HR1 and HR2, of which the first cavity resonator HR1 has an input E for coupling in a microwave signal and the second cavity resonator HR2 has an output A for coupling out a signal. The various known possibilities of coupling and decoupling microwave signals will not be discussed in more detail here.
Das dargestellte Mikrowellenfilter besitzt insgesamt fünf Resonanzkreise R1 ... R5, von denen die Resonanzkreise R1 und R2 im ersten Hohlraumresonator HR1 und die Resonanzkreise R3 und R4 im zweiten Hohlraumresonator HR2 durch TE11n-Wellenmoden (n=1, 2, 3 ...) realisiert sind, welche die durch die Pfeile in Fig. 1 angedeutete Polarisationsrichtungen haben. Der Verlaufsrichtung der E-Feldlinien des in Fig. 2b dargestellten TE11n-Wellenmodes entspricht seiner Polarisationsrichtung. Der fünfte Resonanzkreis R5 des filters ist durch einen TMO1p-Wellenmodus (p = 0, 1, 2 ...) realisiert, der orthogonal zu den TE11n-Wellenmoden polarisiert ist. Den TMO1p-Wellenmode zeigt die Fig. 2a. Seine E-Feldlinien verlaufen in Wellenausbreitungsrichtung, der Polarisationsrichtung (s. Pfeil R5) dieses TMO1p-Wellenmodes.The microwave filter shown has a total of five resonance circuits R1 ... R5, of which the resonance circuits R1 and R2 in the first cavity HR1 and the resonance circuits R3 and R4 in the second cavity HR2 by TE11n wave modes (n = 1, 2, 3 ...) are realized, which have the polarization directions indicated by the arrows in FIG. 1. The direction of the E field lines of the TE11n wave mode shown in FIG. 2b corresponds to its direction of polarization. The fifth resonant circuit R5 of the filter is implemented by a TMO1p wave mode (p = 0, 1, 2 ...), which is polarized orthogonally to the TE11n wave modes. Fig. 2a shows the TMO1p wave mode. Its E field lines run in the direction of wave propagation, the direction of polarization (see arrow R5) of this TMO1p wave mode.
Die in jedem einzelnen Hohlraumresonator vorhandenen orthogonal zueinander polarisierten Wellenmoden können durch Diskontinuitätskoppelglieder, z.B. Abstimmschrauben, welche in bekannter Weise indie Hohlraumwand eingelassen sind, gekoppelt werden.The wave modes which are orthogonally polarized with respect to one another in each individual cavity resonator can be formed by discontinuity coupling elements, e.g. Tuning screws, which are embedded in the cavity wall in a known manner, are coupled.
Kopplungen der Wellenmoden des einen Hohlraumresonators HR1 mit Wellenmoden des anderen Hohlraumresonators HR2 finden über eine zwischen den beiden benachbarten Hohlraumresonatoren angeordnete Koppelblende KB statt. In der Koppelblende KB ist außermittig eine schlitzförmige Koppelöffnung K1 angeordnet. Und zwar liegt diese Koppelöffnung an einer Stelle, wo die magnetischen Feldlinien bzw. Komponenten des TE11n-Wellenmodes des Resonanzkreises R1 im ersten Hohlraumresonator HR1 und die magnetischen Feldlinien des TMO1p-Wellenmodes des Resonanzkreises R5 im zweiten Hohlraumresonator HR2 parallel zueinander verlaufen. Somit erfolgt über die Koppelöffnung K1 eine Kopplung dieser beiden Wellenmoden. Durch die so angeordnete Koppelöffnung K1 wird außerdem der TE11n-Wellenmode des Resonanzkreises R1 des ersten Hohlraumresonators HR1 noch mit dem gleichpolarisierten TE11n-Wellenmode des Resonanzkreises R4 im zweiten Hohlraumresonator HR2 gekoppelt.Couplings of the wave modes of one cavity resonator HR1 with wave modes of the other cavity resonator HR2 take place via a coupling diaphragm KB arranged between the two adjacent cavity resonators. A slot-shaped coupling opening K1 is arranged off-center in the coupling aperture KB. This coupling opening is located at a point where the magnetic field lines or components of the TE11n wave mode of the resonance circuit R1 in the first cavity HR1 and the magnetic field lines of the TMO1p wave mode of the resonance circuit R5 in the second cavity HR2 run parallel to one another. Thus, these two wave modes are coupled via the coupling opening K1. Through the coupling opening K1 thus arranged, the TE11n wave mode of the resonance circuit R1 of the first cavity resonator HR1 is also polarized with the same TE11n wave mode of the resonant circuit R4 coupled in the second cavity HR2.
Desgleichen kann über eine weitere außermittig der Koppelblende KB angeordnete Koppelöffnung K2, die gegenüber der Koppelblende K1 um 90° verschoben ist, eine Kopplung zwischen dem TE11n-Wellenmode des Resonanzkreises R2 im ersten Hohlraumresonator HR1 und dem TMO1p-Wellenmode des Resonanzkreises R5 und auch dem TE11n-Wellenmode des Resonanzkreises R3 im zweiten Hohlraumresonator HR2 bewirkt werden. Wie die vorangehenden Ausführungen zeigen, erreicht man also mit einer sehr einfachen Koppelöffnungsstruktur eine große Vielzahl von Kopplungen zwischen verschieden gearteten bzw. unterschiedlich polarisierten Wellenmoden benachbarter Hohlraumresonatoren.Likewise, via a further coupling opening K2 arranged off-center of the coupling aperture KB, which is shifted by 90 ° with respect to the coupling aperture K1, a coupling between the TE11n wave mode of the resonance circuit R2 in the first cavity resonator HR1 and the TMO1p wave mode of the resonance circuit R5 and also the TE11n -Wave mode of the resonant circuit R3 in the second cavity HR2 can be effected. As the preceding explanations show, a very simple coupling opening structure can be used to achieve a large number of couplings between differently designed or differently polarized wave modes of adjacent cavity resonators.
Von der Wahl der Dimensionierung und der Lage der Koppelöffnung hängt es ab, bei welcher Frequenz eine Wellenmoden-Kopplung stattfindet und wie groß der Kopplungsgrad ist.The choice of the dimensioning and the position of the coupling opening determine the frequency at which a wave mode coupling takes place and the degree of coupling.
Beim vorangehend beschriebenen Ausführungsbeipiel bestand das Mikrowellenfilter aus nur zwei Hohlraumresonatoren. Natürlich können auch Filter aus mehr als nur zwei Hohlraumresonatoren aufgebaut werden, wobei in jedem einzelnen Hohlraumresonator ein (single-mode) zwei (dual-mode) oder drei Wellenmoden (triple-mode) existieren, die je nach gewünschter Filtercharakteristik miteinander zu koppeln sind.In the exemplary embodiment described above, the microwave filter consisted of only two cavity resonators. Of course, filters can also be constructed from more than just two cavity resonators, with one (single-mode) two (dual-mode) or three wave modes (triple-mode) existing in each individual cavity resonator, which can be coupled to one another depending on the desired filter characteristic.
Claims (4)
- A microwave filter composed of at least two cavity resonators in each of which there exists at least one TE or TM mode, with the modes of the two cavity resonators being coupled by means of a coupling aperture disposed between two adjacent cavity resonators, characterized in that a TE mode in one of the two adjacent cavity resonators (HR1, HR2) is coupled with a TM mode in the other cavity resonator.
- A microwave filter according to claim 1, characterized in that at least one coupling iris (K1, K2) is disposed in the coupling aperture at a location where the magnetic field lines of the TE mode and of the TM mode are approximately parallel to one another in the plane of the aperture.
- A microwave filter according to one of the preceding claims, characterized in that the TE mode in the one cavity resonator (HR1) is also coupled, by way of the coupling iris (K1, K2) in the coupling aperture (KB), with the TE mode polarized in the same direction and existing in the other cavity resonator (HR2) in addition to the TM mode.
- A microwave filter according to one of the preceding claims, characterized in that two mutually orthogonally polarized TE modes (R1, R2) exist in one of the two cavity resonators (HR1, HR2) and two likewise mutually orthogonally polarized TE modes (R3, R4) exist in the other cavity resonator as well as a TM mode type (R5) which is orthogonally polarized with respect to both said TE modes; the first TE mode (R1) of the one cavity resonator (HR1) is coupled, via a first coupling iris (K1) in the coupling aperture (KB), with the identically polarized TE mode (R4) and with the TM mode (R5) of the other cavity resonator (HR2) and the second TE mode (R2) of the one cavity resonator (HR1) is coupled, via a second coupling iris (K2), with the identically polarized TE mode (R3) and with the TM mode (R5) of the other cavity resonator (HR2).
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DE3621299 | 1986-06-25 | ||
| DE19863621299 DE3621299A1 (en) | 1986-06-25 | 1986-06-25 | MICROWAVE FILTER |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| EP0250857A2 EP0250857A2 (en) | 1988-01-07 |
| EP0250857A3 EP0250857A3 (en) | 1988-12-07 |
| EP0250857B1 true EP0250857B1 (en) | 1992-07-15 |
Family
ID=6303682
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP87107533A Expired - Lifetime EP0250857B1 (en) | 1986-06-25 | 1987-05-23 | Microwave filter |
Country Status (4)
| Country | Link |
|---|---|
| US (1) | US4734665A (en) |
| EP (1) | EP0250857B1 (en) |
| CA (1) | CA1271532A (en) |
| DE (2) | DE3621299A1 (en) |
Families Citing this family (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5012211A (en) * | 1987-09-02 | 1991-04-30 | Hughes Aircraft Company | Low-loss wide-band microwave filter |
| FR2675952B1 (en) * | 1991-04-29 | 1993-10-22 | Alcatel Telspace | MICROWAVE FILTER WITH ONE OR MORE RESONANT CAVITIES. |
| US5254963A (en) * | 1991-09-25 | 1993-10-19 | Comsat | Microwave filter with a wide spurious-free band-stop response |
| DE19523220A1 (en) * | 1995-06-27 | 1997-01-02 | Bosch Gmbh Robert | Microwave filter |
| IT1284353B1 (en) * | 1996-01-30 | 1998-05-18 | Cselt Centro Studi Lab Telecom | MULTIMODAL CAVITY FOR WAVE GUIDE FILTERS. |
| IT1284354B1 (en) * | 1996-01-30 | 1998-05-18 | Cselt Centro Studi Lab Telecom | MULTIMODAL CAVITY FOR WAVE GUIDE FILTERS. |
| US5774030A (en) * | 1997-03-31 | 1998-06-30 | Hughes Electronics Corporation | Parallel axis cylindrical microwave filter |
| US7982561B2 (en) * | 2008-09-05 | 2011-07-19 | Harris Corporation | Resonator system for an RF power amplifier output circuit |
| US8665039B2 (en) | 2010-09-20 | 2014-03-04 | Com Dev International Ltd. | Dual mode cavity filter assembly operating in a TE22N mode |
| CN112436260A (en) * | 2020-11-25 | 2021-03-02 | 苏州灿勤通讯技术有限公司 | Novel TE mode dielectric resonator |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3697898A (en) * | 1970-05-08 | 1972-10-10 | Communications Satellite Corp | Plural cavity bandpass waveguide filter |
| US3646481A (en) * | 1971-03-12 | 1972-02-29 | Bell Telephone Labor Inc | Waveguide mode transducer |
| US4129840A (en) * | 1977-06-28 | 1978-12-12 | Rca Corporation | Array of directional filters |
-
1986
- 1986-06-25 DE DE19863621299 patent/DE3621299A1/en not_active Withdrawn
-
1987
- 1987-05-23 EP EP87107533A patent/EP0250857B1/en not_active Expired - Lifetime
- 1987-05-23 DE DE8787107533T patent/DE3780367D1/en not_active Expired - Lifetime
- 1987-06-23 US US07/065,566 patent/US4734665A/en not_active Expired - Fee Related
- 1987-06-23 CA CA000540336A patent/CA1271532A/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| CA1271532A (en) | 1990-07-10 |
| DE3621299A1 (en) | 1988-01-07 |
| EP0250857A2 (en) | 1988-01-07 |
| EP0250857A3 (en) | 1988-12-07 |
| US4734665A (en) | 1988-03-29 |
| DE3780367D1 (en) | 1992-08-20 |
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