交替隐式时域有限差分分析有耗介质电磁波传播

针对电磁波在有耗介质中的传播特点,提出了改进的交替方向隐式时域有限差分(ADI-FDTD)算法来研究电磁波在有耗介质中的传播特性。改进后的算法可改善传统ADI-FDTD为提高计算效率导致的计算精度下降的缺点。证明了算法的无条件稳定性,并分析了算法的数值色散。通过算例对比验证了算法的有效性和对计算精度的改善。将算法应用到金属球体在空气中、地面上方和海平面上方的电磁散射分析中,仿真结果表明:介质损耗在一定程度增大电磁散射的同时,会加大电磁散射的震荡。

Electromagnetic wave propagation in loss media based on ADI-FDTD

Aiming at the propagation characteristics of electromagnetic waves in loss media, a modified alternative direction implicit finite difference time domain (ADI-FDTD) method is proposed to solve the problem. The modified method can improve the disadvantage of the traditional ADI-FDTD method, which improves the computational effeciency on the cost of accuracy. The unconditional stability of the algorithm is proved, while the numerical dispersion is also analyzed. The algorithm is validated effectively, and it could also improve computational accuracy, which has been proved by examples comparison. The algorithm is applied to analyze the scattering of a metal sphere in air, on the bottom of ground and sea. The simulation shows that the amplitude and oscillation of the scattering increase in the loss media.