A Novel Six-Port Three-Way Filtering Splitter-Combiner Network Using a Lattice of Coupled Resonators Realized in Ridge Waveguides

This paper presents a novel three-way nine-pole compact cross-coupled resonator network that simultaneously realizes a filtering function and a three-way splitter or combiner function. These functionalities find application in beam forming networks and in solid-state high-power amplifier designs. The novel six port device uses a lattice of nine resonators arranged in three rows to realize the filtering and coupling functions at once. Coupling matrix formulation for the lattice network enables the synthesis of the integrated filtering and combining functions. Among the possible implementations, physical realization in ridge waveguide technology offers an attractive option with its compact cross-section and wide bandwidth single mode operation. The proposed design helps in integrating more functional blocks in a smaller number of modules and reduces component counts and system complexity. A prototype design was fabricated and tested demonstrating good results without any tuning.