A Stable Mixed TDFEM Based on Filtering Spatial Unstable Modes

The time step of the traditional mixed time-domain finite element method (TM-TDFEM) based on E-B co-simulation is small due to the fine features, which causes tremendous number of steps for time marching, increases rounding errors and raises computational costs. In this paper, a stable mixed TDFEM (SMTDFEM) is implemented, which can reach unconditional stability by introducing the filtering spatial unstable modes method. Numerical results illustrate the accuracy and efficiency of the proposed method.