COMPACT WIDE UPPER-STOPBAND BPF USING OPEN STUB LOADED DUALMODE RESONATOR

摘要

A novel compact bandpass filter (BPF) with good in band and wide upper-stopband performances is realized using open stub loaded dual-mode resonator. The resonator generates two operating modes in the desired band and the even-mode resonance frequency can be flexibly controlled by the disc-shaped open stub at central plane, whereas the odd-mode one is fixed. By simply adjusting the dimension of the disc-shaped open stub, the even resonant mode falls down and works together with the odd mode to form a BPF. Two other pairs of open stubs are mainly applied to suppress the high harmonic resonant modes and obtain good match, respectively. Experimental results of the fabricated filter show good agreement with the simulated results.