A NOVEL CROSSED SLOTTED PATCH DUAL-MODE BANDPASS FILTER WITH TWO TRANSMISSION ZEROS

摘要

This article presents a miniaturized dual-mode bandpass filter (BPF) with two transmission zeros and low insertion-loss using crossed slotted patch resonator. The BPF is mainly formed by a λ/2 patch resonator which is a pair of crossed slots with unequal widths is embedded in the center. By tuning the perturbation element, which resulted from the unequal slot widths along the diagonal, two resonant modes are excited and a pair of transmission zeros are generated to improve the selectivity of the BPF performance. The proposed filter at center frequency (f{sub}0) of 1.55 GHz has very good measured characteristics including the bandwidth of 1.49-1.62 GHz (3-dB fractional bandwidth of 8.4%), low insertion loss of 1.74×0.35 dB. The measured filter performance is in good agreement with the simulated response.