Advanced Subgrid FD Technique for Modeling Waveguide Structures with Curved Conducting and Dielectric Boundaries

An efficient generalized finite difference (FD) algorithm is presented which incorporates the combination of a direct orthogonalization subgrid technique for regions of high field intensity, a locally conformal grid for modeling curved perfectly conducting bodies, and a modified contour-path integral FD method to deal with curved dielectric surfaces. The combined technique reduces CPU time and storage requirements. The flexibility of the method is demonstrated at the example of a lateral coax feed with dielectric coating. The theory is verified by available measurements.