Media type: E-Article Title: A triple‐mode bandpass filter using a modified circular patch resonator Contributor: Serrano, Ariana L. C.; Correra, Fatima Salete imprint: Wiley, 2009 Published in: Microwave and Optical Technology Letters Language: English DOI: 10.1002/mop.23950 ISSN: 0895-2477; 1098-2760 Keywords: Electrical and Electronic Engineering ; Condensed Matter Physics ; Atomic and Molecular Physics, and Optics ; Electronic, Optical and Magnetic Materials Origination: Footnote: Description: <jats:title>Abstract</jats:title><jats:p>This article presents a triple‐mode bandpass filter using a modified circular patch resonator. Etched slots in the resonator split the <jats:italic>TM</jats:italic><jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/tex2gif-stack-1.gif" xlink:title="urn:x-wiley:08952477:media:MOP23950:tex2gif-stack-1" /> degenerate fundamental modes and also perturb the <jats:italic>TM</jats:italic><jats:inline-graphic xmlns:xlink="http://www.w3.org/1999/xlink" xlink:href="graphic/tex2gif-stack-2.gif" xlink:title="urn:x-wiley:08952477:media:MOP23950:tex2gif-stack-2" /> mode, approximating their resonant frequencies to form a third‐order bandpass filter. A 2.42 GHz centered filter was designed and fabricated. Experimental results showed a fractional bandwidth of 29%, return loss better than 16 dB, insertion loss of 0.5 dB, and good second harmonic band rejection. The filter exhibited a size reduction of 51% compared with a filter using an unperturbed circular patch resonator at the same frequency. © 2008 Wiley Periodicals, Inc. Microwave Opt Technol Lett 51: 178–182, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.23950</jats:p>