UWB bandpass filter with wide notch using hybrid microstrip/CPW scheme, defected microstrip array, and defected corner scheme

In this paper, a compact ultra-wideband (UWB) bandpass filter with a wide notch base on the hybrid microstrip/coplanar waveguide (CPW) scheme, defected microstrip array (DMA), and defected corner scheme (DCS) is proposed. First, the UWB operation is employed using the hybrid microstrip/CPW scheme. Secondly, the DMA is introduced to achieve the wide notch in the UWB passband, which could cancel the interferences (i.e., the total 5-GHz band WLAN signals). Thirdly, the DCS embedded in the CPW is introduced to further improve the UWB passband flatness and return loss level. Then, a filter is implemented, which has the merits of good UWB frequency responses, a wide notch with 3-dB bandwidth from 5.1 up to 5.9 GHz, and a compact size.