NOVEL QUAD-BAND FILTER WITH HIGH FREQUENCY RATIO AND CONTROLLABLE BANDWIDTHS USING SLHSIRs AND SLQSIRs

摘要

This article presents a quad-band bandpass filter (QBBPF) using a set of stub-loaded half-wavelength step impedance resonators operated at the second and third passbands (2.4/3.5 GHz) and a set of stub-loaded quarter-wavelength step impedance resonators operated at the first and fourth passbands (1.3/5.8 GHz), and the frequency ratio is 4.46 times. Furthermore, all the frequencies and bandwidths can be adjusted. Finally, the proposed filter is designed and fabricated. The measured results are in good agreement with the full-wave simulation results. (C) 2014 Wiley Periodicals, Inc.