有限元/边界积分方法在海面及其上方弹体目标电磁散射中的应用

本文将有限元/边界积分方法(FE/BIM)结合区域分解方法引入到粗糙海面及其上方目标 的电磁散射问题的研究中. 由于积分边界可以以任意形状设置在距模型表面任意远的距离处, 故本文采用共形人工边界结合区域分解建模方法截断模型的开放计算区域以减少求解未知量, 在截断区域内部采用有限元方法求解, 而计算区域的边界条件通过边界积分方程方法得到. 通过与矩量法获得的数值计算结果进行比较, 证明了该混合算法及模型处理方法的正确性, 进而研究了海面上方弹体目标的电磁散射特性, 并讨论了其双站散射系数随电磁波入射角度、目标高度、海面风速以及弹体尺寸的电磁散射特性变化情况. 本文结果可用于反演复杂背景下的目标信息及目标探测等领域.关键词：电磁散射粗糙海面目标有限元/边界积分方法

Electromagnetic scattering from missile target above sea surface with finite element/boundary integral method

In this work, the finite element/boundary integral method (FE/BIM) combined with the domain decomposition method is introduced to study the electromagnetic scattering from the target above the rough sea surface. As the integral boundary can be set at anywhere with an arbitrary shape, the conformal truncated boundary is built to reduce the unknowns of the computational region combined with the domain decomposition method. In the interior region, the finite element method is used to solve the problem, whereas the artificial boundary condition can be obtained by the boundary integral method. The strategy of hybrid FE/BIM and the modeling method are presented with their validity evaluated by the method of moment, then bistatic scattering properties of a missile above the sea surface are discussed, and their dependence upon different incident angles, target height, wind speed above the sea, and the size of the missile are discussed in detail. The information of targets and the target detection can be retrieved and analyzed by the results in this paper.
Keywords：electromagnetic scatteringrough sea surfacetargetFE/BIM