Solution of 2D scattering from large inhomogeneous dielectric cylinders with shifted frequency internal equivalence principle

Abstract

Radiation and scattering problems involving dielectric objects can be formulated by using surface integral equation (SIE) methods or volume integral (VIE) equation methods. SIE methods employ unknown currents that reside on the surface of the geometry and are employed to formulate problems involving homogeneous bodies. VIE methods, on the other hand, employ unknown current densities that are distributed inside the geometry and allow problems involving inhomogeneous bodies to be solved. Numerical solution to these problems start with the discretization of the integral equations by a method of moments (MoM) scheme. Discretized integral equations are then converted into matrix equations which are solved to obtain unknown current coefficients. Number of elements in these matrix equations are closely related to the electrical size of the problem. Since VIE methods use voluminous currents, matrix sizes can quickly become very large. Usually these computationally intensive operations are required in multiple frequencies covering a bandwidth. In this case, lengthy solution process needs to be repeated for each frequency of interest.