Improved convolutional perfectly matched layer with auxiliary differential equation for the weakly conditionally stable finite‐difference time‐domain method

Abstract

On basis of the auxiliary differential equation, an improved convolutional perfectly matched layer (CPML) scheme has been proposed and applied to the three-dimensional weakly conditionally stable (WCS) finite-difference time-domain (FDTD) method. With this method, the maximum error is reduced effectively, and the absorption effect is more obvious. The simulation results show the proposed improvement scheme with more calculation accuracy than initial CPML under various Courant-Friedrich-Levy number (CFLN) conditions while ensuring similar calculation time and memory cost. Moreover, when CFLN is increased to eight, the calculation time is <30% of the traditional method, which proved the proposed method with more calculation efficiency.