Small-Size Waveguide Diplexer Based on E-Plane Quasi-Planar Filters

Abstract

We propose a new small-size version of a waveguide diplexer based on quasi-planar filters with E-plane ridge sections and inductive diaphragms on a single metal inset made of a thin foil. The diplexer contains an E-plane waveguide bifurcation and a matching stepwise transition. The effective hybrid method, which is based on the Galerkin method allowing for the field singularity at the edges, the mode matching method, and the generalized scattering matrix method, has been developed for electrodynamic analysis of the given class of diplexers. We present characteristics of the optimized version of the design of a centimeter-wave diplexer, whose length is approximately 1.5 times shorter compared with known counerparts.