Alavikia Babak, Ramahi Omar M
Department of Electrical and Computer Engineering, University of Waterloo, Waterloo, Ontario, Canada.
J Opt Soc Am A Opt Image Sci Vis. 2011 Dec 1;28(12):2510-8. doi: 10.1364/JOSAA.28.002510.
This work presents a novel finite-element solution to the problem of scattering from a finite and an infinite array of cylindrical objects with arbitrary shapes and materials over perfectly conducting ground planes. The formulation is based on using the surface integral equation with Green's function of the first or second kind as a boundary constraint. The solution region is divided into interior regions containing the cylindrical objects and the region exterior to all the objects. The finite-element formulation is applied inside the interior regions to derive a linear system of equations associated with nodal field values. Using two-boundary formulation, the surface integral equation is then applied at the truncation boundary as a boundary constraint to connect nodes on the boundaries to interior nodes. The technique presented here is highly efficient in terms of computing resources, versatile, and accurate in comparison with previously published methods. The near and far fields are generated for a finite and an infinite array of objects. While the surface integral equation in combination with the finite-element method was applied before to the problem of scattering from objects in free space, the application of the method to the important problem of scattering from objects above infinite flat ground planes is presented here for the first time, to our knowledge.
本文提出了一种新颖的有限元解决方案，用于解决在理想导电接地平面上，由任意形状和材料的有限和无限圆柱阵列引起的散射问题。该公式基于使用具有第一类或第二类格林函数的表面积分方程作为边界约束。求解区域分为包含圆柱物体的内部区域和所有物体外部的区域。在内部区域应用有限元公式，以导出与节点场值相关的线性方程组。使用双边界公式，然后将表面积分方程应用于截断边界作为边界约束，以将边界上的节点与内部节点连接起来。与先前发表的方法相比，本文提出的技术在计算资源方面效率很高，通用性强且准确。针对有限和无限物体阵列生成了近场和远场。虽然表面积分方程与有限元方法的组合以前曾应用于自由空间中物体的散射问题，但据我们所知，本文首次将该方法应用于无限平坦接地平面上方物体散射的重要问题。
