一种降低内存的时域散射计算方法——RPSTD

A Memory-Reduced Time Domain Method of Simulating Electromagnetic Scattering——RPSTD

提出一种降低内存的时域伪谱法——RPSTD。PSTD方法基于Maxwell旋度方程,应用FFT(FastFou rierTransform)算法近似表示空间导数。由于FFT具有高阶精度,理论上每个波长只需划分两个网格即可计算目标的宽带电磁散射特性。为进一步减少存储量,RPSTD方法在PSTD方法的基础上,在Maxwell旋度方程两边取散度,将PSTD方法存储空间6个场分量减缩为存储4个独立的场分量,而其他两个场分量可由4个独立的场分量导出。将RPSTD用于二维散射计算,结果表明RPSTD的计算精度与PSTD相当。

This paper presents a memory-reduced method reduced pseudo-spectral time domain （RPSTD）. The method is based on Maxwell＇ s equations and FFT is used to take spatial derivatives of the field components approximately. Due to the high accuracy in the spatial derivatives, PSTD requires a smaller number of unknowns （ even two cells in a wavelength） to solve wide-band scattering problems. To reduce the memory requirements, one takes divergence of both sides of Maxwell＇ s equations and only four independent components per cell are stored in the whole domain . The other two components can be obtained from the four independent components. Considering two-dimensional scattering case, as an example, the result of RPSTD equal to the PSTD.