A diagonal split-cell model for the high-order symplectic FDTD scheme

Abstract — A high-order symplectic FDTD (SFDTD) scheme using the diagonal split-cell model is presented to analyze electromagnetic scattering of the curved three-dimensional perfectly conducting objects. One the one hand, for the undistorted cells, the fourth-order accurate spatial difference is employed. On the other hand, for the completely distorted cells, the treatment of the curved surfaces is based on the diagonal split-cell model. Finally, for the partially distorted cells, the interpolation strategy is proposed to keep the field components continuous. The numerical experiments suggest that the diagonal SFDTD scheme can obtain more accurate results than both the staircased SFDTD scheme and the traditional diagonal FDTD method. Furthermore, in view of the high numerical stability, the improved symplectic scheme does not need to decrease time increment to comply with the stability criterion. DOI: 10.2529/PIERS060903035033 1