Analysis of waveguide discontinuity problems using PML substructure method

The waveguide is decomposed into several substructures in the longitudinal direction, and PML absorbing boundary is treated as one of them. The transverse section of the substructures is discretized with the finite element method, a precise integration method based on the Riccati equations is used for the longitudinal integration to generate the export stiffness matrices, and then the waveguide discontinuity problems are expected to be solved through the combination of the substructures. Numerical examples demonstrate that, the waveguide discontinuity problems can be effectively solved with this method, the disadvantage that the artificial boundary must be far away from the non-uniform region can be overcome, and the field near the non-uniform region can be worked out.