并行时域电场积分方程方法在动态海面二维电磁散射中的应用

采用并行时域电场积分方程方法对动态海面的二维瞬态散射特性进行研究。为了保证该方法的后期稳定性,时间基函数和空间基函数采用二阶B样条基函数和三角基函数,矩阵元素采用时间维度精确解析、空间奇异部分精确解析进行计算;为了减少对无限海面进行截断带来的边缘效应,入射波采用锥形调制高斯脉冲;结合信息传递接口(MPI)技术和稀疏矩阵压缩存储技术,对不同时刻的海面进行瞬态散射分析。大量的数值算例证明了该方法在计算动态海面的二维瞬态散射问题时的正确性,还可以保证后期的稳定性,提高计算效率,减少对计算机内存需求。

Application of parallel time domain electric field integral equation to two-dimensional electromagnetic scattering from time-evolving ocean surfaces

In this paper, a parallel time domain electric field integral equation is applied to numerical simulation of two-dimensional electromagnetic scattering from time-evolving ocean surfaces. The proper choice of temporal basis functions and precise evaluations of matrix elements are used to overcome the late-time instability. Quadratic B-spline function is employed as the temporal basis function, while triangle function is employed as the spatial basis function. The matrix elements are precisely evaluated with analytical formulae for time integrals terms and singular terms. The tapered modulated Gaussian pulse is used to reduce the edge effects resulted from cutting down the infinite sea surfaces. A scheme of message passing interface and compressed storage of sparse matrix are adopted to improve the computational efficiency and reduce the computational storage requirement. Numerical results demonstrate that the method proposed is accurate and efficient for analyzing transient scattering from time-evolving ocean surfaces.