基于GPU加速FDTD算法的掠入射下一维大尺度粗糙面电磁散射研究

In this paper, the graphic processor unit (GPU) implementation of the finite-difference time domain (FDTD) algorithm is presented to investigate the electromagnetic (EM) scattering from one dimensional (1-D) large scale exponential rough soil surface with low grazing incident angle. The FDTD lattices are truncated by uniaxial perfectly matched layer (UPML), in which the finite-difference equations are carried out for the total computation domain. Using Compute Unified Device Architecture (CUDA) technology, significant speedup ratios are achieved for different incident frequencies, which demonstrates the efficiency of GPU accelerated the FDTD method. The validation of our method is verified by comparing the numerical results with these obtained by CPU, which shows favorable agreements. Furthermore, our parallel implementation is employed to study the impact of the incident angle on EM scattering from 1-D soil surface, especially under low grazing incidence. Finally, the influences of the characteristic parameters of correlation length and root mean square (rms) height on bistatic scattering coefficient of 1-D large scale rough surface with low grazing incidence are also analyzed and discussed in detail.