Design of dual-band filter using defected split-ring resonator combined with interdigital capacitor

A novel type of dual-band microstrip structure and its equivalent circuit are investigated, which is composed of defected split-ring resonator and interdigital capacitor. The influence of design parameters on the frequency characteristics is discussed, then a dual-band microstrip filter, which has two passbands of 1.8–2.5 GHz and 5.5–5.9 GHz with a transmission zero, is designed and fabricated. © 2007 Wiley Periodicals, Inc. Microwave Opt Technol Lett 49: 2104–2106, 2007; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/mop.22673