Efficient Modeling of Open Structures Using Nonuniform Leapfrog ADI-FDTD

The perfectly matched layer (PML) using the split-field formulation has been implemented in a recently developed leapfrog alternating-direction-implicit finite-difference time-domain method (leapfrog ADI-FDTD) for efficient modeling of open structures. To further enhance computational efficiency and modeling accuracy, a nonuniform numerical grid is incorporated in the proposed formulations. Numerical simulations of a 2-D TE wave in an open region and an electromagnetic band-gap Y-power splitter are performed to verify the implementation with the PML. The results show that with the proposed method, CPU time savings can be up to 50% of that of a conventional ADI-FDTD.