High-order Nystrom solution for electromagnetic scattering by multiscale objects based on combined field integral equation

Electromagnetic (EM) interactions with multiscale objects widely exist in practice and high-order accuracy of solutions for the problem is very desirable for accurate analysis. The combined field integral equation (CFIE) is used to describe the problem in the integral equation approach since it can remove the internal resonance problem. The Nystrom method is a robust solver for EM integral equations, but its high-order scheme is less extensively studied. This work aims at the multiscale EM problems and develops a high-order Nystrom method (HONM) to solve the governing CFIE. The accurate evaluation of hypersingular and near-hypersingular integrals is a key in the HONM and new formulations are developed for multiscale structures based on Green's theorem. Numerical examples for EM scattering by multiscale conducting objects are provided to illustrate the approach and good results are acquired.