EP1538692A1 - Filtre en guide rectangulaire à pôles extraits - Google Patents
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- EP1538692A1 EP1538692A1 EP03293113A EP03293113A EP1538692A1 EP 1538692 A1 EP1538692 A1 EP 1538692A1 EP 03293113 A EP03293113 A EP 03293113A EP 03293113 A EP03293113 A EP 03293113A EP 1538692 A1 EP1538692 A1 EP 1538692A1
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- 230000005540 biological transmission Effects 0.000 claims abstract description 49
- 238000012546 transfer Methods 0.000 claims abstract description 17
- 230000001939 inductive effect Effects 0.000 claims abstract description 8
- 210000000554 iris Anatomy 0.000 claims description 8
- 230000008859 change Effects 0.000 claims description 4
- 230000008878 coupling Effects 0.000 abstract description 3
- 238000010168 coupling process Methods 0.000 abstract description 3
- 238000005859 coupling reaction Methods 0.000 abstract description 3
- 230000004044 response Effects 0.000 description 11
- 230000015572 biosynthetic process Effects 0.000 description 10
- 238000003786 synthesis reaction Methods 0.000 description 10
- 238000000034 method Methods 0.000 description 9
- 238000003780 insertion Methods 0.000 description 6
- 230000037431 insertion Effects 0.000 description 6
- 230000008901 benefit Effects 0.000 description 3
- 239000003990 capacitor Substances 0.000 description 3
- 238000004519 manufacturing process Methods 0.000 description 3
- 230000008569 process Effects 0.000 description 3
- 230000035945 sensitivity Effects 0.000 description 3
- 238000004088 simulation Methods 0.000 description 3
- 238000010276 construction Methods 0.000 description 2
- 238000006880 cross-coupling reaction Methods 0.000 description 2
- 238000013461 design Methods 0.000 description 2
- 230000009466 transformation Effects 0.000 description 2
- 239000000919 ceramic Substances 0.000 description 1
- 238000012512 characterization method Methods 0.000 description 1
- 238000012940 design transfer Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000011156 evaluation Methods 0.000 description 1
- 230000001747 exhibiting effect Effects 0.000 description 1
- 238000000605 extraction Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 230000007246 mechanism Effects 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
- 230000009897 systematic effect Effects 0.000 description 1
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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
- H01P1/209—Hollow waveguide filters comprising one or more branching arms or cavities wholly outside the main waveguide
Definitions
- the present invention relates to a new structure for high-power and low insertion losses microwave filters with symmetrical or asymmetrical transfer function response to implement in rectangular waveguide H-plane configuration.
- the present invention seeks to overcome or reduce one or more of the above problems by means of an electric transmission structure for implementing a transfer function of N degree that can incorporate finite real-frequency transmission zeros, the structure comprising: a main rectangular waveguide without change in height (H-plane configuration) wherein the body of the structure comprises a plurality of resonant cavities placed adjacent to each other and connected with inductive irises and at least one cavity with a double electrical behaviour, i.e. operating as a resonant cavity in transmission at central frequency of the passband and simultaneously introducing a controlled transmission zero out of the passband.
- H-plane configuration wherein the body of the structure comprises a plurality of resonant cavities placed adjacent to each other and connected with inductive irises and at least one cavity with a double electrical behaviour, i.e. operating as a resonant cavity in transmission at central frequency of the passband and simultaneously introducing a controlled transmission zero out of the passband.
- a further object of the present invention is to provide a new structure for cavity filters assuring a drastic reduction in mass and volume in comparison with the all-pole transfer functions with the same rejection specification.
- Another object of this invention is to provide a new cavity arrangement with a double controlled electrical behaviour that allows to introduce transmission zeros at finite real frequencies.
- Yet another object of the invention is a synthesis technique for the synthesis of N-degree filters with N-transmission zeros at real frequencies by means of extracted poles.
- an electric transmission structure in rectangular waveguide for implementing a transfer function with transmission zeros at finite real frequencies.
- This structure comprises a plurality of resonant cavities placed adjacent to each other with inductive irises between adjacent cavities, and at least one cavity with a double controlled electrical behaviour connected to the "classical" resonant cavities by means of inductive irises.
- the structure according to the invention has the advantage of allowing the filter to be mechanized in a simple and very compact construction without slots or critical dimensions to ensure a high RF power handling capability, increasing the multipactor margin in space applications. In addition, the cost and the manufacturing dimensional tolerance sensitivity are reduced. This construction allows using large cavities to increase the Q in order to maintain low insertion losses at high frequencies.
- a further advantage of the invention is that fine adjustment of all elements, i.e., cavities and coupling between them, is possible by means of tuning screws. These are not part of the structure but elements to compensate for the mechanical tolerances.
- the first task is to generate the transfer function that in the more general case can be always expressed as the ratio of two finite-degree polynomials with complex coefficients (from here on, the degree of the transfer function is the degree of the numerator polynomial).
- the evaluation of this mathematical response must fit with the out of band rejection specifications and the return losses in the passband.
- the next step is to synthesize a low-pass prototype network, i.e., to obtain the values of the electrical components such as capacitors, inductors, admittance/impedance inverters, frequency invariant reactances/susceptances and transmission lines.
- the response of this electrical network must be the same as that of the mathematical transfer function.
- band pass filters a transformation is necessary to translate the low-pass response to the considered frequency band. Equally important, since mechanical structure is the rectangular waveguide, a one-to-one correspondence between the electrical circuit elements and the physical resonant cavities and irises is necessary.
- FIG. 1 shows as an example, the low pass prototype of a 3th degree network with 3 transmission zeros in the real frequency axis, wherein ⁇ 1, ⁇ 2, ⁇ 3, ⁇ 4 and ⁇ 5 represent electrical lengths corresponding to transmission lines, K is an admittance inverter, 1 is a unity inverter, L1, L2, and L3 are inductors, and jX1, jX2, and jX3 are frequency invariant reactances.
- FIG. 2 shows another example, the low pass prototype of a 4th degree network with 2 transmission zeros in the real frequency axis, wherein ⁇ 1, ⁇ 2, ⁇ 3 and ⁇ 4 represent electrical length corresponding to transmission lines, C1 and C2 are capacitors, L1 and L2 are inductors, jX1 and jX2 are frequency invariant reactances and jB1 and jB2 are frequency invariant susceptances.
- FIG. 3 shows the equivalent rectangular wave guide H-plane structure to implement the network corresponding to FIG. 2, wherein ⁇ 2* and ⁇ 3* represent electrical length corresponding to transmission lines, K1, K2 and K3 are admittance inverters, C1 and C4 are the equivalent circuit elements of the cavities with double electrical behaviour, C2 and C3 are the equivalent circuit elements of the classical resonant cavities.
- FIG. 4 is a view of an exemplary rectangular waveguide realization of the network shown in FIG. 3 according to the invention. 1 and 2 are the input and output of the structure respectively. C1 and C4 are cavities with double electrical behaviour. C2 and C3 are resonant cavities. K1, K2 and K3 are inductive irises for coupling adjacent cavities.
- FIG. 5 is a perspective representation of a cross section along the line VV of the rectangular waveguide of FIG. 4 wherein the position of the cavities can be clearly observed.
- this structure is composed by two different types of resonant cavities; C2 and C3 are two inductive coupled (shunt reactive iris K2) transmission cavities.
- C1 and C4 are a new structure having a double controlled electrical behaviour; each one operates as a resonant cavity in transmission at central frequency of the passband and simultaneously introduces a controlled transmission zero out of the band.
- C1 and C4 are inductive coupled to C2 and C3 by means of shunt reactive irises K1 and K3 respectively. Therefore, it is possible to guarantee the required return losses and at the same time to introduce a transmission zero in the desired position. If the rectangular waveguide elements are correctly dimensioned the electrical response of the structure will be very similar to that predicted by the mathematical filtering function. However, in the synthesis process an attention will be paid to the circuital values, in order to obtain the most adequate results because of the mechanical constraints.
- cavities with double behaviour can therefore be obtained by way electromagnetic simulation in conjunction with optimisation of their structure. This simulation can provide different dimensions depending on the requirements of the design in each particular case.
- these double behaviour cavities C1 and C4 are shown to represent an extension to a side of the filter structure, clearly being different from the rest of the cavities, e.g. C2 and C3.
- the cavities with double behaviour may adopt a variety of structures, for example instead of being extended to a side of the waveguide, i.e. having a width larger than the general width of the waveguide structure as shown in figures 4 and 5, they could have a width being smaller than the general width of the rectangular waveguide (not shown).
- minimum phase networks like the one shown above, is more desirable because element-value sensitivity is less and network complexity is reduced. If cross-couplings are employed, the designer does not have specific control over the positions of the zeros because there is not a one to one correspondence between zeros and cross-couplings. For this reason such kind of structures are very sensitive and difficult to adjust. However, by implementing the extracted-pole technique every transmission zero, is controlled independently. This is a very important asset from the engineering point of view in order to minimize the sensitivity of the network for mass production.
- the synthesis technique is based on a systematic process to extract the (attenuation) poles.
- the transmission zeros on the imaginary axis of the complex plane are asymmetrically disposed, it is necessary to extract them individually.
- the synthesis process is composed by two different steps.
- the initial part of the synthesis procedure is carried out in terms of the transfer function of the filter and includes several extraction cycles (as many as finite real transmission zeros) in order to extract the finite poles, each cycle comprising the steps of determining the phase lengths of the unity inverters, the residue of every pole (shunt series resonator), the capacitors and the invariant shunt reactances to cope with the asynchronously tuned network.
- the synthesis procedure improves further to transform the prototype network into the equivalent rectangular waveguide structure arrangement according to the invention.
- the transformation converts the phase lengths of the transmission lines into an admittance inverter plus a new phase length, as shown in FIG.3.
- Figure 6 illustrates a simulation of the electromagnetic response of the waveguide structure wherein curve A represents insertion loss and curve B represents return loss.
- Filters obtained according to the invention can be connected in arrangements so as to provide a multiplexing or demultiplexing network. Examples of such connections are by connecting a plurality of filters by rectangular waveguides sections and tee's (connection devices in the form of T, known in the art) the height of each is equal to that of the rectangular waveguide of the filters, i.e. in H-plane configuration.
- An alternative connection is obtained by means of transmission line sections and tee's, and in particular said transmission line sections can be coaxial.
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Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP03293113A EP1538692A1 (fr) | 2003-12-05 | 2003-12-08 | Filtre en guide rectangulaire à pôles extraits |
Applications Claiming Priority (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP03293107 | 2003-12-05 | ||
| EP03293107.3A EP1566856A1 (fr) | 2003-12-05 | Filtre en guide rectangulaire à pôles extraits | |
| EP03293113A EP1538692A1 (fr) | 2003-12-05 | 2003-12-08 | Filtre en guide rectangulaire à pôles extraits |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| EP1538692A1 true EP1538692A1 (fr) | 2005-06-08 |
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Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| EP03293113A Ceased EP1538692A1 (fr) | 2003-12-05 | 2003-12-08 | Filtre en guide rectangulaire à pôles extraits |
Country Status (1)
| Country | Link |
|---|---|
| EP (1) | EP1538692A1 (fr) |
Cited By (16)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| WO2007039360A1 (fr) | 2005-09-30 | 2007-04-12 | Ericsson Ab | Filtre éliminateur de bande de guide d'onde |
| CN103117438A (zh) * | 2013-03-04 | 2013-05-22 | 电子科技大学 | 太赫兹波导腔体滤波器 |
| CN103326093A (zh) * | 2013-04-19 | 2013-09-25 | 上海大学 | 新型交叉耦合基片集成波导带通滤波器 |
| RU2517397C1 (ru) * | 2013-01-09 | 2014-05-27 | Алексей Валентинович Палицин | Волноводный фильтр верхних частот |
| RU2583062C1 (ru) * | 2015-04-13 | 2016-05-10 | Алексей Валентинович Палицин | Волноводный фильтр нижних частот |
| CN105896008A (zh) * | 2016-04-27 | 2016-08-24 | 南京邮电大学 | 一种在高频和低频均含有传输零点的紧凑型带通滤波器 |
| US9515362B2 (en) | 2010-08-25 | 2016-12-06 | Commscope Technologies Llc | Tunable bandpass filter |
| CN109713414A (zh) * | 2019-03-01 | 2019-05-03 | 江苏德是和通信科技有限公司 | 一种有限传输零点位置可调的调频带通滤波器 |
| CN109713412A (zh) * | 2018-12-20 | 2019-05-03 | 常州机电职业技术学院 | 一种可调谐e面切割h面波导带通滤波器及其设计方法 |
| CN109755704A (zh) * | 2019-01-09 | 2019-05-14 | 内蒙古大学 | 低结构深宽比的双模矩形波导滤波器及其多阶滤波器件 |
| CN110767965A (zh) * | 2019-11-01 | 2020-02-07 | 南京工程学院 | 一种具有快速滚降特性的太赫兹全波段波导带通滤波器 |
| CN110896163A (zh) * | 2019-11-19 | 2020-03-20 | 摩比科技（深圳）有限公司 | 可实现单个带外传输零点的介质波导滤波器 |
| CN112599949A (zh) * | 2020-12-24 | 2021-04-02 | 京信射频技术(广州)有限公司 | 介质滤波器及其滤波回路 |
| CN113036343A (zh) * | 2019-12-25 | 2021-06-25 | 深圳市大富科技股份有限公司 | 一种通信设备及其滤波器 |
| CN113675562A (zh) * | 2020-05-14 | 2021-11-19 | 大富科技(安徽)股份有限公司 | 一种滤波器及通信设备 |
| CN119764822A (zh) * | 2024-11-28 | 2025-04-04 | 东南大学 | 一种波导阵列天线以及一种加载石英的太赫兹缝隙波导滤波天线 |
Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6096090A (en) * | 1997-02-20 | 2000-08-01 | Agence Spatiale Europeenne | Method of designing an electrical filter and filter thus obtained |
| GB2359197A (en) * | 1999-12-11 | 2001-08-15 | Bsc Filters Ltd | Enhanced performance waveguide diplexers |
| US20020024410A1 (en) * | 2000-06-05 | 2002-02-28 | Marco Guglielmi | Dual-mode microwave filter |
| DE10208666A1 (de) * | 2002-02-28 | 2003-09-04 | Marconi Comm Gmbh | Bandpassfilter mit parallelen Signalwegen |
-
2003
- 2003-12-08 EP EP03293113A patent/EP1538692A1/fr not_active Ceased
Patent Citations (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6096090A (en) * | 1997-02-20 | 2000-08-01 | Agence Spatiale Europeenne | Method of designing an electrical filter and filter thus obtained |
| GB2359197A (en) * | 1999-12-11 | 2001-08-15 | Bsc Filters Ltd | Enhanced performance waveguide diplexers |
| US20020024410A1 (en) * | 2000-06-05 | 2002-02-28 | Marco Guglielmi | Dual-mode microwave filter |
| DE10208666A1 (de) * | 2002-02-28 | 2003-09-04 | Marconi Comm Gmbh | Bandpassfilter mit parallelen Signalwegen |
Non-Patent Citations (2)
| Title |
|---|
| GUGLIELMI M ET AL: "IMPLEMENTING TRANSMISSION ZEROS IN INDUCTIVE-WINDOW BANDPASS FILTERS", IEEE TRANSACTIONS ON MICROWAVE THEORY AND TECHNIQUES, IEEE INC. NEW YORK, US, vol. 43, no. 8, 1 August 1995 (1995-08-01), pages 1911 - 1915, XP000523076, ISSN: 0018-9480 * |
| HIDALGO-CARPINTERO, I.; PADILLA-CRUZ, M.J.: "Moderate bandwidth filter for multiplexer applications", MICROWAVE CONFERENCE, 2003. 33RD EUROPEAN, vol. 33, no. 3, 7 October 2003 (2003-10-07) - 9 October 2003 (2003-10-09), Munich, pages 1243 - 1246, XP002273345 * |
Cited By (21)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US7786828B2 (en) | 2005-09-30 | 2010-08-31 | Ericsson Ab | Waveguide bandstop filter |
| CN101317299B (zh) * | 2005-09-30 | 2013-01-16 | 爱立信股份有限公司 | 波导带阻滤波器 |
| WO2007039360A1 (fr) | 2005-09-30 | 2007-04-12 | Ericsson Ab | Filtre éliminateur de bande de guide d'onde |
| US9515362B2 (en) | 2010-08-25 | 2016-12-06 | Commscope Technologies Llc | Tunable bandpass filter |
| RU2517397C1 (ru) * | 2013-01-09 | 2014-05-27 | Алексей Валентинович Палицин | Волноводный фильтр верхних частот |
| CN103117438A (zh) * | 2013-03-04 | 2013-05-22 | 电子科技大学 | 太赫兹波导腔体滤波器 |
| CN103326093A (zh) * | 2013-04-19 | 2013-09-25 | 上海大学 | 新型交叉耦合基片集成波导带通滤波器 |
| RU2583062C1 (ru) * | 2015-04-13 | 2016-05-10 | Алексей Валентинович Палицин | Волноводный фильтр нижних частот |
| CN105896008A (zh) * | 2016-04-27 | 2016-08-24 | 南京邮电大学 | 一种在高频和低频均含有传输零点的紧凑型带通滤波器 |
| CN105896008B (zh) * | 2016-04-27 | 2018-09-25 | 南京邮电大学 | 一种在高频和低频均含有传输零点的紧凑型带通滤波器 |
| CN109713412B (zh) * | 2018-12-20 | 2024-03-29 | 常州机电职业技术学院 | 一种可调谐e面切割h面波导带通滤波器及其设计方法 |
| CN109713412A (zh) * | 2018-12-20 | 2019-05-03 | 常州机电职业技术学院 | 一种可调谐e面切割h面波导带通滤波器及其设计方法 |
| CN109755704A (zh) * | 2019-01-09 | 2019-05-14 | 内蒙古大学 | 低结构深宽比的双模矩形波导滤波器及其多阶滤波器件 |
| CN109713414A (zh) * | 2019-03-01 | 2019-05-03 | 江苏德是和通信科技有限公司 | 一种有限传输零点位置可调的调频带通滤波器 |
| CN109713414B (zh) * | 2019-03-01 | 2023-11-21 | 江苏德是和通信科技有限公司 | 一种有限传输零点位置可调的调频带通滤波器 |
| CN110767965A (zh) * | 2019-11-01 | 2020-02-07 | 南京工程学院 | 一种具有快速滚降特性的太赫兹全波段波导带通滤波器 |
| CN110896163A (zh) * | 2019-11-19 | 2020-03-20 | 摩比科技（深圳）有限公司 | 可实现单个带外传输零点的介质波导滤波器 |
| CN113036343A (zh) * | 2019-12-25 | 2021-06-25 | 深圳市大富科技股份有限公司 | 一种通信设备及其滤波器 |
| CN113675562A (zh) * | 2020-05-14 | 2021-11-19 | 大富科技(安徽)股份有限公司 | 一种滤波器及通信设备 |
| CN112599949A (zh) * | 2020-12-24 | 2021-04-02 | 京信射频技术(广州)有限公司 | 介质滤波器及其滤波回路 |
| CN119764822A (zh) * | 2024-11-28 | 2025-04-04 | 东南大学 | 一种波导阵列天线以及一种加载石英的太赫兹缝隙波导滤波天线 |
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