Analysis, design, and sensitivity study of substrate integrated waveguide circuits by using equivalent circuit models

The design of complex substrate integrated waveguide (SIW) circuits requires the use of sophisticated full-wave simulation tools. When the complexity of the circuit increases, the computational effort required for the analysis and especially for the optimization of complex SIW circuits becomes prohibitive. For this reason the use of equivalent circuit models is very beneficial. This paper presents the derivation of parametric and multimodal equivalent circuit models of SIW discontinuities, based on the boundary integral-resonant mode expansion (BI-RME) method. To proof the validity of the models, the use of these equivalent circuits for the modeling and design of some SIW circuits, as well as for fast sensitivity study, is presented.