MINIATURE DUAL-MODE DUAL-BAND BANDPASS FILTER WITH IMPROVED PASSBANDS PERFORMANCE FOR 2.4/5.2 GHz WLAN APPLICATION

摘要

In this article, a miniature dual-mode dual-band bandpass filter (BPF) based on novel complementary center-stub-loaded stepped-impedance resonators has been presented. By loading an open stub at the center of stepped-impedance resonator, the center frequency of the fundamental even-mode could be independently controlled, whereas that of the fundamental odd-mode is fixed. A dual-mode dual-band BPF using complementary configuration is implemented with three transmission zeros. To validate the design and analysis, a prototype filter has been designed and fabricated with its two bands located at 2.4/5.2 GHz for WLAN. The measured performances show good agreements with those of the coupling matrix analysis and electromagnetic simulation.