Surface integral equation using numerical green's function of anisotropic inhomogeneous media

Surface integral equation (SIE) leveraging the analytic homogeneous-medium Green's function is only suitable for investigating piecewise homogeneous objects. In this paper, we demonstrate that by taking advantage of numerical Green's function (NGF), SIE methods can be extended to model arbitrarily inhomogeneous and anisotropic media. In our scheme, NGFs of complicated media are computed with differential equation (DE) methods where the domain can be truncated by arbitrary boundary conditions. Electromagnetic scatterings of anisotropic geometries are simulated to validate the proposed scheme, where NGFs are obtained by the finite element method (FEM).