Design of a miniaturized microstrip dual-mode dual-band bandpass filter

Abstract

A miniaturized microstrip dual-mode dual-band bandpass filter is presented in this article. The filter is constructed by two slow-wave dual-mode resonators and two feed lines. To excite dual-mode response, each dual-mode resonator is coupled by an L-shape feed line. To realize multiple transmission zeroes outside the two passbands, parasitic coupling between two feed lines are also introduced. With these considerations, the proposed dual-mode dual-band filter has the properties of compact size, high selectivity, and two transmission poles inside each passband. Demonstrator filter is designed and validated with good agreement between the full-wave electromagnetic simulations and measurements. Copyright © 2011 Wiley Periodicals, Inc.