A WCS-PSTD Method for Solving Electromagnetic Problems Both With Fine and Electrically Large Structures

A time domain method which is based on the hybrid implicit explicit difference technique and pseudospectral (PS) scheme is presented for solving 3D Maxwell´s equations. The maximum time-step size in this method is only determined by one spatial discretization and the spatial discretization only needs two cells per wavelength. The 3D formulations of this method are presented and the time stability condition is demonstrated. This method is mainly useful for the simulations of electromagnetic problems where both fine and electrically large structures are employed. Compared with the conventional finite-difference time-domain (FDTD) method and weakly conditionally stable (WCS)-FDTD method, this method has higher computational efficiency and less memory requirement, which is demonstrated through numerical examples.