An Explicit and Unconditionally Stable FDTD Method for Electromagnetic Analysis

In this paper, an explicit and unconditionally stable finite-difference time-domain (FDTD) method is developed for electromagnetic analysis. Its time step is not restricted by the space step, and its accuracy is ensured for the time step chosen based on accuracy. The strength of the conventional explicit FDTD is thus preserved in avoiding a system matrix solution, while the shortcoming of the conventional FDTD is eliminated in the time step's dependence on space step. Numerical experiments in both 2-D and 3-D simulations have demonstrated the performance of the proposed method in stability and efficiency without sacrificing accuracy.