Electromagnetic transverse electric-wave inverse scattering of a conductor by the genetic algorithm

The genetic algorithm is used to reconstruct the shape of a perfectly conducting cylinder illuminated by transverse electric (TE) waves. A cylinder of unknown shape scatters the incident TE wave in a free space and the scattered field is recorded outside. Based on the boundary condition and the measured scattered field, a set of nonlinear integral equations is derived and the imaging problem is reformulated into an optimization problem. The genetic algorithm is then employed to find out the global extreme solution of the cost function. Numerical results demonstrated that the genetic algorithm can tackle the inverse problem of a larger scatterer. Even when the electrical dimension of the scatterer exceeds one wave-length and the initial guess is far from the exact one, good reconstruction was obtained. In such a case, gradient-based methods often get stuck in a local extreme. In addition, the effect of Gaussian noise on the reconstruction results is investigated.