辅助方程-双向隐式差分法的电磁散射研究

Electromagnetic scattering using ADEs-ADI-FDTD method

在辅助差分方程(ADEs)的基础上结合交替隐式时域有限差分方法(ADI-FDTD),提出ADEs-ADI-FDTD方法用以计算色散媒质的电磁散射问题。由于三维ADI-FDTD方法的复杂性,在此采用了全分裂场形式的场量以简化完全匹配层(PML)吸收边界的处理及在连接边界处入射场的加入。针对Debye型色散媒质,利用极化强度辅助差分系列方程推导了ADEs-ADI-FDTD方法中电、磁场的迭代方程及其相关参数表达式,最后通过对色散媒质和各向同性等离子体等物体进行仿真计算,计算结果显示了本文算法在时间上的高效性和精确性。

This paper presents a novel method to simulate the electromagnetic scattering with Debye dispersion medium, which combines the alternative direction implicit-FDTD （ADI-FDTD） with auxiliary differential equations （ADEs）. The ADI technology here adopts the split matched layers （PML）, which can field equations, just as field in the perfectly lead the incident wave on the adjacent boundaries easily. Moreover, the update equations of electric and magnetic field components in this method are derived to the Debye medium. Finally examples are described to exhibit the high efficiency and accuracy of the proposed method compared with conventional FDTD.