A tunable ultra-wideband band-stop filter based on EBG structures using MEMS technology

An ultra-wideband (UWB) band-stop filter (BSF) is presented using novel design to tune the resonant frequency by micro-electromechanical systems' (MEMS) switch, based on electromagnetic band-gap (EBG) and coplanar-waveguide (CPW) structures. The model of the compact BSF is cascaded by three EBG resonators. The BSF is operated from 15 to 20 GHz with good stop rejection and sharp roll off frequency. Its stop rejection levels are -30 dB in both the lower and upper stopband, and return loss is less than 0.5 dB in the stop-band. A tunable BSF is designed by tuning the frequency using a folded MEMS switch. The center frequency of stop-band of BSF is changed from 5 to 15 GHz, by tuning the switch height of MEMS switch.