Analysis of waveguide discontinuities using edge elements in a hybrid modematching/finite elements approach

A mode matching (MM)/finite element method (FEM) for the analysis of wavegu ide discontinuities is presented. The hybrid approach described combines th e computational efficiency of the modal analysis with the versatility and f lexibility of FEM and enables us to accurately model arbitrary cross sectio n waveguides, where modal expansions cannot be derived analytically. The pr oposed procedure is based on the edge element expansion of the transverse f ield components for the direct calculation of the coupling integrals involv ed in the MM formulation. Numerical and experimental results are presented to show the validity and the accuracy of the method.