Tunable Embedded Notch Structure for UWB bandpass filter

A reconfigurable ultra-wideband (UWB) bandpass filter (BPF) with tunable notch band for UWB system is presented in this paper. The UWB BPF adopts the proposed stub-loaded multiple-mode resonator (MMR) structure and RF-MEMS switched capacitor network which is used for electronic tuning. The filter is printed on a Roger's RT/Duriod 6010 substrate with the dimensions of 10 mm × 10 mm × 1.2 mm and relative dielectric constant of 10.8. The key parameters were analyzed, simulated and optimized by using the high frequency structure EM simulator, thereby getting concrete dimension of the filter. The simulated results demonstrate that the bandwidth of the UWB BPF is from 3.1 GHz to 10.6 GHz and the centre frequency of notch band is tuned from 5.5 GHz to 6.5 GHz with four tuning states which are 5.7 GHz, 6.1 GHz, 6.3 GHz and 6.5 GHz respectively.