Integral Equations for the Scattering by a Three Dimensional Inhomogeneous Chiral Body

Abstract

Integral equations are obtained for the electromagnetic (EM) scattering by an inhomogeneous, isotropic, three dimensional chiral body. The chiral body is assumed to be in free space, and it can be attached to a perfect electric conducting (PEC) body. The integral equations are obtained with the help of vector-dyadic identities and the free space dyadic Green's function. These equations are expressed in terms of a volume integral with the electric field as the unknown and surface integrals where the tangential components of the electric field and its curl are the unknowns. The integral equations are then transformed into a linear system of simultaneous equations by means of the moment method technique. Expressions for the scattered field in the far-zone are also obtained by replacing the dyadic Green's function and its curl with their large argument approximations. Furthermore, closed form expressions are obtained for the fields and dipole moments induced inside an electrically small, homogeneous chiral sphere where it is assumed that the fields are constant. Finally, closed form expressions and numerical results for the fields scattered by the small chiral sphere and its bistatic echo area are also obtained.