An Efficient Algorithm for Surface Integral Equation Based on Mesh-Free Scheme

An efficient algorithm for solving surface integral equation based on mesh-free scheme is proposed. The surface current is represented by a set of shape functions instead of conventional Rao–Wilton–Glisson (RWG) basis functions in the method of moments (MoM). The shape functions are constructed on some distributed nodes without explicitly requiring continuity conditions. Unlike the RWG, the basis function in this letter is not reliant on the tessellation and can be used with nonconformal meshes. In addition, it can be used flexibly to mix different discretization scales of grids. Numerical results demonstrate that scattering from objects can be computed efficiently with the multilevel fast multipole method (MLFMM) combined with adaptive cross approximation (ACA).