Efficient Analysis of Metallic and Dielectric Posts in Parallel-Plate Waveguide Structures

A mode-matching method is proposed for the accurate and fast analysis of structures composed by metallic and dielectric posts in a parallel-plate waveguide environment. The incident and scattered fields on each post are expressed with a cylindrical mode expansion. After enforcing the appropriate boundary conditions, a set of matrix equations is derived. The corresponding solution are the coefficients of the field vector expansion. The method is validated with several examples found in the literature and compared with the results obtained with the commercial software Ansys HFSS. The proposed method can be used for a very fast electromagnetic analysis of substrate integrated waveguides and substrate integrated slab waveguides.