NESA-VIE for Electromagnetic Analysis of Inhomogeneous Dielectrics

In this paper, we propose a nested equivalent source approximation-volume integral equation (NESA-VIE) algorithm for matrix low-rank compression to analyze the electromagnetic scattering problem of inhomogeneous dielectrics. Unlike SIE, VIE introduces the dielectric contrast to reflect the difference of dielectric constants in different parts of the object, so it can be used to model and analyze inhomogeneous dielectrics. In the framework of NESA, the original volume integral matrix equation is now decomposed into the product of the radiation matrix ‘V’ of the RWG -to-SWG interaction, the translation matrix ‘D’ and the receiving matrix ‘U’ of the SWG-to-RWG interaction, thus reducing the memory and computation. The construction of ‘U’ and ‘V’ mentioned above is modified to compress VIE rather than SIE in the original NESA. Numerical results of RCS calculation show the correctness of the proposed method.