A Method for Fast and Reliable Analysis and Optimization of Side-Coupled Cavity Filters and Multiplexers

This paper presents an efficient segmentation method of a filter made up of side-coupled cavities that use a reduced complexity model. The model is built by using the reactance matrix of only three parallel waveguides, either coaxial or hollow, coupled via apertures among them. This allows building the databases necessary for fast and reliable analysis and optimization of very complex filters and multiplexers. The method was used to design a low-cost eight-channel coaxial-cavity input multiplexer.