Circular Resonator Based Compact Ultra- Wideband Bandpass and Notched Filters with Rejection of 5-6 GHz Band

Abstract — In this paper, a circular ultra wideband (UWB) bandpass filter and notch filter using microstrip with wide passband, low insertion and return loss are presented. The proposed bandpass filter covers the UWB indoor mask range from 3.1GHz to 10.6GHz. The filter has a circular plate resonator with interdigital coupling has been designed to act as bandpass filter with passband of 8.25 GHz. The notch filter is proposed using four open stub structure in the bandpass structure. The notch filter is derived from the bandpass filer, the notch filter is designed to introduce notch in the frequency range from (5-6) GHz. The designed filters are successfully simulated by electromagnetic simulator, IE3D. The filters exhibit low insertion loss over the desired passband, and a good out-of-band performance