Title (en)

Inline waveguide filter with up to two out-of-band transmission zeros

Title (de)

Inline-Mikrowellenfiler mit bis zu zwei Übertragungsnullstellen ausserhalb des Bandes.

Title (fr)

Filtre micro-onde en ligne possèdant jusqu'à deux zéros de transmission hors la bande passante.

Publication

EP 1564835 A1 20050817 (EN)

Application

EP 04425096 A 20040216

Priority

EP 04425096 A 20040216

Abstract (en)

An inline microwave filter implemented by means of a metallic hollow body having a given number N of resonant cavities separated to each other by coupling means, such as capacitive/inductive irises and/or inductive posts, arranged to obtain a given N<th> order Chebyshev frequency response. Two input/output waveguide ports are coupled to the respective ending resonant cavities in a manner that at least one waveguide port is also directly coupled to another resonant cavity adjacent to the ending one, to obtain an extra transmission zero outside the passband of the filter. The distance of the extra transmission zero from the corresponding limit of the passband increases with the offset of the waveguide from the midline between the coupled cavities. In a first embodiment of the filter a capacitive iris delimits the adjacent resonant cavities coupled to the waveguide port, to obtain an extra transmission zero in the lower out-of-band frequency range. In a second embodiment of the filter an inductive iris delimits the adjacent resonant cavities coupled to the waveguide port, to obtain an extra transmission zero in the higher out-of-band frequency range. In a third embodiment of the filter a capacitive iris and an inductive one delimit the adjacent resonant cavities respectively coupled to each waveguide port, to obtain two extra transmission zeros in the out-of-band frequency ranges at the two sides of the passband. In a fourth embodiment of the filter two capacitive irises delimit the adjacent resonant cavities respectively coupled to each waveguide port, to obtain two extra transmission zeros in the lower out-of-band frequency range. In a fifth embodiment of the filter two inductive irises delimit the adjacent resonant cavities respectively coupled to each waveguide port, to obtain two extra transmission zeros in the higher out-of-band frequency range. (fig. 10) <IMAGE>

IPC 1-7

H01P 1/208

IPC 8 full level

H01P 1/208 (2006.01)

CPC (source: EP)

H01P 1/208 (2013.01)

Citation (applicant)

• US 6304160 B1 20011016 - LOI KEITH N [US], et al
• G.L.MATTHAEI; L. YONG; E. M. T. JONES: "Microwave Filters, Impedance-Matching Networks, and Coupling Structures", 1980, ARTECH HOUSE BOOKS
• N. MARCUVITZ: "Waveguide Handbook", 1951, MCGRAW-HILL BOOK COMPANY
• R. E. COLLIN: "Foundation for Microwave Engineering", 1992, MCGRAW-HILL
• JAN KOCBACH; KJETIL FOLGERO: "Design procedure for waveguide filters with cross-couplings", PROC. 2002 IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM
• UWE ROSENBERG; SMAIN AMARI; JENS BORNEMANN: "Inline waveguide filters with arbitrarily located attenuation poles", PROC. 2002 ASIA PACIFIC MICROWAVE CONF., November 2002 (2002-11-01), pages 229 - 232

Citation (search report)

• [XY] US 6304160 B1 20011016 - LOI KEITH N [US], et al
• [A] GB 1304970 A 19730131
• [Y] GUGUEN C ET AL INSTITUTE OF ELECTRICAL AND ELECTRONICS ENGINEERS: "Inductive iris band-pass filter integrating floating inserts for pseudo-elliptic response", 2003 IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM DIGEST.(IMS 2003). PHILADELPHIA, PA, JUNE 8 - 13, 2003, IEEE MTT-S INTERNATIONAL MICROWAVE SYMPOSIUM, NEW YORK, NY : IEEE, US, vol. VOL. 3 OF 3, 8 June 2003 (2003-06-08), pages 945 - 948, XP010645061, ISBN: 0-7803-7695-1
• [A] PARK J-S ET AL: "A NOVEL WAVEGUIDE BANDPASS FILTERS WITH AN ASYMMETRICAL ATTENUATION POLE", 31ST EUROPEAN MICROWAVE CONFERENCE PROCEEDINGS. LONDON, SEPT. 25 - 27, 2001, PROCEEDINGS OF THE EUROPEAN MICROWAVE CONFERENCE, LONDON : CMP, GB, vol. VOL. 1 OF 3 CONF. 31, 25 September 2001 (2001-09-25), pages 323 - 326, XP001044806, ISBN: 0-86213-148-0

Designated contracting state (EPC)

AT BE BG CH CY CZ DE DK EE ES FI FR GB GR HU IE IT LI LU MC NL PT RO SE SI SK TR

DOCDB simple family (publication)

EP 1564835 A1 20050817; EP 1564835 B1 20100414; AT E464670 T1 20100415; DE 602004026535 D1 20100527

DOCDB simple family (application)

EP 04425096 A 20040216; AT 04425096 T 20040216; DE 602004026535 T 20040216