Comparative study between branch-waveguide directional couplers and broad-wall slot couplers

A generalized scattering matrix of the generalized two-port discontinuity is proposed for use in the analysis, design, and optimization of four-port waveguide directional couplers. The proposed analysis method can consider symmetrical and asymmetrical structures without any geometrical restriction. Agreement with experimental data is excellent. A comparative study of the reflection and coupling performance between branch-waveguide directional couplers and broad wall slot couplers is presented. It is shown that by using branch-waveguide directional couplers a flat coupling can be achieved over a wider bandwidth