Multibranch Curvilinear Rao–Wilton–Glisson Basis Functions for Electromagnetic Scattering From Perfect Electric Conducting Targets

A multibranch curvilinear Rao–Wilton–Glisson (MB-CRWG) basis function is proposed to solve surface integral equations with nonconformal curvilinear meshes. The derivation of the MB-CRWG basis function is given. The structure of the MB-CRWG basis function can be divided into positive and negative parts. The positive part is one curvilinear triangular patch, and the negative part is composed of several curvilinear triangular patches. The MB-CRWG can conveniently connect two surfaces discretized with curvilinear triangular patches of different sizes. Numerical examples of the electromagnetic scattering from multiscale perfect electrically conducting targets are given to demonstrate the effectiveness of the proposed basis function.