A General Scheme for the Discontinuous Galerkin Time-Domain Modeling and S-Parameter Extraction of Inhomogeneous Waveports

A general numerical scheme is proposed for the waveport modeling and scattering-parameter (S-parameter) extraction of inhomogeneous waveports with the discontinuous Galerkin time-domain method. In this scheme, the waveports are truncated with perfectly matched layers with a hybrid mesh automatically extruded from the mesh of the physical device to be simulated. The waveports are then excited by a total-field/scattered-field technique, with which the incident and scattered waves can be obtained for an accurate calculation of the S-parameters. A novel eigenmode solver is also developed to calculate the required modal profiles for the eigenmodes in both homogeneous and inhomogeneous waveports. Special attention is paid to the S-parameter extraction for evanescent modes, which has been a difficult task for time-domain simulations. Numerical examples are given to validate the proposed numerical scheme.