Coaxial narrowband filters using a versatile suspended resonator

In this paper, two four-pole filters at X-band are presented, both designs use a coaxial quarter wavelength resonator suspended in air by short circuits between the coaxial center and outer conductor. Different couplings between suspended resonators have been used to obtain a Chebyshev and a quasi-e...

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Detalles Bibliográficos
Autores: IGNACIO LLAMAS GARRO, ALONSO CORONA CHAVEZ
Tipo de recurso: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2011
País:México
Institución:Instituto Nacional de Astrofísica, Óptica y Electrónica
Repositorio:Repositorio Institucional del INAOE
Idioma:inglés
OAI Identifier:oai:inaoe.repositorioinstitucional.mx:1009/1694
Acceso en línea:http://inaoe.repositorioinstitucional.mx/jspui/handle/1009/1694
Access Level:acceso abierto
Palabra clave:info:eu-repo/classification/cti/1
info:eu-repo/classification/cti/22
info:eu-repo/classification/cti/2203
Descripción
Sumario:In this paper, two four-pole filters at X-band are presented, both designs use a coaxial quarter wavelength resonator suspended in air by short circuits between the coaxial center and outer conductor. Different couplings between suspended resonators have been used to obtain a Chebyshev and a quasi-elliptic response. The Chebyshev filter was designed to have a 9.2 GHz centre frequency with a 4% fractional bandwidth. The second design is a quasi-elliptic filter composed of two vertically stacked rectangular coaxial lines, where one pair of resonators is placed on the lower coaxial line and another pair is located on the upper line. Coupling between coaxial lines is achieved through an iris in the common coaxial ground plane. The quasi-elliptic filter has been designed to have a centre frequency of 9.1 GHz with a 4% fractional bandwidth. Two transmission zeros located at the sides of the passband have been successfully achieved with the proposed filter topology. Experimental results for both designs are presented, where a good agreement with simulations has been obtained.