Design of A Commensurate Line Bandpass Filter with Generalized Chebyshev Response

In this paper, a commensurate line bandpass filter (BPF) is designed and tested. This BPF consists of three sections of transmission line and a short-circuited coupled line, all of which have the same electrical length. It can not only achieve good return loss, but also feature good frequency selectivity. The impedance of the transmission line sections and the coupled line can be derived by the proposed synthesis method. The experimental results verify our proposed BPF.