A Comprehensive Analysis of Quasiplanar Waveguides for Millimeter-Wave Application

Quasiplanar waveguides are analyzed which consist of a thin, partially metallized dielectric substrate inserted in the E-plane of a rectangular waveguide. Several slots or strips in symmetric or non-symmetric positions are allowed on each substrate surface. The analysis is based on a simplified formulation of the spectral domain immittance matrix followed by a Galerkin´s method. The analysis has been extended to include the computation of higher order propagating and evanescent modes as well as the characteristic impedances of the dominant modes. Numerical results are presented for various configurations with strips or slots on one or both air-dielectric interfaces illustrating the flexibility of the applied method.