An Efficient Asymptotic Closed-Form Dyadic Green's Function for Grounded Double-Layered Anisotropic Uniaxial Material Slabs

Abstract

An efficient asymptotic closed-form dyadic Green's function for the grounded double-layered anisotropic uniaxial geometry is developed. The large parameter of this asymptotic development is directly proportional to the lateral separation between the source and observation points. However the asymptotic solution remains accurate even for very small (a few tenths of a wavelength) lateral separation of the source and field points. Thus, the use of the asymptotic approximation of the Green's function can lead to a very efficient moment method (MM) solution for the current on the scatterer within the anisotropic unaxial substrates. Moreover, the asymptotic closed form dyadic Green's function has been cast in such a form that the physical behavior of the electromagnetic fields due to anisotropy of the medium reveals itself through a simple mathematical parameters. Thus, the physical understanding of the interaction of the spatially confined source with a grounded anisotropic (uniaxial) double-layered slab is gr...