A Locally-Implicit Leap-Frog DGTD Method for ITBC Modeling

This paper develops a locally-implicit leap-frog discontinuous Galerkin time-domain (LILF-DGTD) method to model impedance transmission boundary condition (ITBC) in a complex medium. In the governing equation corresponding to Ampere's law, the implicit time integration is implemented for element pairs adjacent to ITBC surfaces, while in the governing equation related to Faraday's law, the conventional explicit scheme is employed. Furthermore, the scenario where the ITBC adjacent to the anisotropic medium is considered. Numerical results demonstrate the stability and accuracy of LILF-DGTD compared with traditional leap-frog DGTD and finite element method (FEM).