A Modified Dielectric Contrast based Integral Equation for 2D TE Scattering by Inhomogeneous Domains

TL;DR

This paper introduces a modified integral equation method for 2D TE scattering in inhomogeneous domains, improving numerical stability and accuracy through a new dielectric contrast definition and RWG basis functions.

Contribution

It proposes a novel formulation that reduces numerical challenges and enhances geometric conformity in TE scattering problems involving inhomogeneous media.

Findings

Accurate scattering field computations validated against analytical solutions.

Convergence improves with mesh refinement, demonstrating robustness.

Method effectively handles dielectric interfaces with tangential continuity.

Abstract

This work presents a modified domain integral equation approach for the forward problem of TE scattering, employing a modified definition of dielectric contrast and discretizing the electric field density using Rao-Wilton-Glisson (RWG) basis functions. The proposed formulation mitigates the numerical challenges introduced by the gradient-divergence operator in traditional electric field-based vector formulations. The use of RWG basis functions over triangular meshes enhances geometric conformity, ensures tangential continuity across dielectric interfaces, and facilitates the application of well known singularity extraction techniques for numerical accuracy. Validation through numerical experiments on a two-layered dielectric cylinder demonstrates excellent agreement between computed and analytical scattered fields. Convergence studies confirm improving solution accuracy with mesh refinement indicating robustness with respect to discretization without increasing the iterations.