volume | PIER Journals

Abstract

Generalized cross-coupled filters require implementation of both positive and negative cross-coupled elements. A positive element frequently uses inductive coupling, while a negative one uses capacitive coupling. Traditional methods for realizing capacitive couplings, which are difficult to adjust in practice, have included the use of capacitive probes in coaxial cavity. And this kind of n-order cross-coupled filters without the coupling between input and output ports can only produce 2-n transmission zeros at most. In this paper, we present a convenient method for capacitive coupling. Based on the method a four-order cross-coupled filter is realized, and the measured results match well with the theoretical prediction. Especially, there are three transmission zeros near the pass band.

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Dr. Jin-Song Zhan

Dr. Jia-Li Wang