Non-redundant synthesis of filters with dual-mode and triple-mode stepped impedance resonators

In this paper, the non-redundant synthesis of BPFs with dual-mode and triple-mode stepped impedance resonators is studied. Network models of the multi-mode-resonator filters and conventional parallel-coupled-line filters are shown to be equivalent. Non-redundant design procedure is proposed and design equations are then derived based on broadband approximate design procedure. Two design examples are given to show that the proposed design procedure is much simpler and yields responses just as good as those obtained by more tedious exact synthesis.