Design and analysis of a multiple notched UWB-BPF based on microstrip-to-CPW transition

The manuscript presents a broadside coupled ultra-wideband (UWB) bandpass filter with quasi-elliptic response having multiple transmission zeros (TZs) in/out of the UWB spectrum. Developed on a low cost substrate (FR4), the basic geometry consists of a short-circuited co-planar waveguide (CPW) in ground coupled to the back-to-back arranged microstrip lines on the top. This broadband balun architecture leads to a 3rd order bandpass filter (BPF) with good quasi-elliptic frequency characteristics. Later, split ring resonators (SRRs) and folded SRRs (FSRRs) are placed adjacent to the input/output (I/O) feeding lines to develop the multiple in/out band TZs. The proposed structure is fabricated and measured for its frequency characteristics. The notched-BPF occupies an area of 21.6 x 16 mm(2).

Automated summary

This manuscript presents a low-cost ultra-wideband bandpass filter with quasi-elliptic response and multiple transmission zeros. The filter is based on a broadside coupled architecture and demonstrates good frequency characteristics.