An effective method for electromagnetic scattering from a coated object partially buried in a dielectric rough surface

An effective method combined with finite element method (FEM) and boundary integral method (BIM) is presented in this paper to study the composite electromagnetic scattering from a 2-D coated object partially buried in a 1-D dielectric rough surface. The field within the coated object is modelled by FEM, while the coupling field between the object and rough surface is considered by BIM. The fields inside and outside the object are coupled together via boundary conditions on the boundary of the object. Since the boundary of the object is divided by the rough surface into two parts with different electromagnetic properties, the boundary conditions on the object are more complicated. A detailed derivation of the FEM-BIM formula for the composite model is given in this paper. Our numerical code is validated by the method of moments (MoM), and several numerical simulations are conducted to discuss the scattering characteristics.