Multi-Region Finite-Difference Time-Domain (MR-FDTD) Based on Domain-Optimal Green's Functions

A multi-region (MR-) finite-difference time-domain (FDTD) scheme for solving two-dimensional sparsely-populated problems based on domain-optimal Green's functions is proposed. The scheme uses a discrete Green's function (DGF) on the FDTD lattice to truncate the local sub-regions and thus reduces reflection error on the local boundary. A continuous Green's function (CGF) is implemented to pass the influence of external fields into each FDTD region which mitigates the numerical dispersion and anisotropy of standard FDTD. Numerical results will demonstrate the accuracy of this approach.