Electromagnetic Scattering by a Homogeneous Chiral Obstacle: Boundary Integral Equations and Low-Chirality Approximations

Time-harmonic electromagnetic waves are scattered by a homogeneous chiral obstacle. The corresponding transmission problem is reduced to a pair of coupled integral equations over S, where S is the interface between the obstacle and the surrounding medium. This is done using a generalization of the Stratton–Chu representation that is valid for chiral media. The integral equations obtained are a generalization of those obtained by Müller for a homogeneous dielectric obstacle. Finally, we develop approximations for low-chirality obstacles. These approximations can be computed using simple modifications to existing codes for solving Müller’s equations.