Unified solution of various dielectric-loaded ridge waveguides with a mixed spectral-domain method

A mixed spectral-domain method is developed and applied to the analysis of various dielectric-loaded ridge waveguides. Magnetic surface currents at apertures are identified as unknowns in auxiliary structures. Spectral Green´s functions are formulated for these structures using the spectral immittance approach. Mixing different spectral domains existing on the two sides of an aperture in a spectral Galerkin approach then leads to the characteristic equations required for the dispersion analysis. The simplicity and numerical efficiency of the conventional spectral-domain immittance approach, which cannot be applied directly to the present structures, are maintained. Representative results are obtained to illustrate the application of the method