A New Synthesis for Tri-band Filtering Power Dividers Applying Equal-Ripple Level

A new synthesis method for designing tri-band filtering power dividers (TBFPDs) is presented in this paper. Based on the existing frequency transformation method, the bandwidth control of the bands is increased, so that the designed TBFPD has a more flexible bands and a wider bandwidth. For validation, a third-order TBFPD working at three independent bands is designed. Wider bandwidth, lower insertion loss and better isolation is attained so as to successfully validate the correctness of the proposed design theory.