On the modularized analysis method for ceramic‐filled waveguide cavity filters

Abstract

This article makes a systematic study on an analysis method called modularized analysis method (MAM) for both inline and cross-coupled ceramic-filled waveguide cavity filters (WCFs). Compared with full-wave numerical analysis method, equivalent circuit model method (ECMM) and mode-matching (MM) method, MAM achieves a good balance between accuracy and running speed. First, the network analysis principles of MAM through cumulative product of transfer matrices for inline WCFs and generalized connection method for cross-coupled WCFs are presented. Second, the determination of split planes in process of module decomposition, the key factor affecting MAM for ceramic-filled WCFs, is well examined. It is shown that setting split planes at chamfer ends is beneficial for improving the accuracy of MAM. Moreover, for cross-coupled ceramic-filled WCFs, an unequal-chamfer scheme needs to be adopted in order to set split planes correctly. Third, three analysis examples are given to verify the effectiveness of MAM for both inline and cross-coupled ceramic-filled WCFs. Finally, the practicability of MAM in design of crosscoupled ceramic-filled WCFs is demonstrated by combining it with space mapping algorithm.