Volume 39, Issue 3 (May 2011)
Time Domain Inverse Scattering for a Homogenous Dielectric Cylinder by Asynchronous Particle Swarm Optimization
In this paper, we propose a time domain inverse scattering technique for reconstructing the electromagnetic properties of a homogeneous dielectric cylinder based on the finite difference time domain method and the asynchronous particle swarm optimization (APSO). The homogeneous dielectric cylinder with unknown electromagnetic properties is illuminated by transverse magnetic pulse and the scattered field is recorded outside. By minimizing the discrepancy between the measured and estimated scattered field data, the location, shape, and permittivity of the dielectric cylinder are reconstructed. The inverse problem is resolved by an optimization approach and the global searching scheme APSO is then employed to search the parameter space. A set of representative numerical results is presented for demonstrating that the proposed approach is able to efficiently reconstruct the electromagnetic properties of the homogeneous dielectric scatterer even when the initial guess is far away from the exact one. In addition, the effects of Gaussian noises on imaging reconstruction are also investigated.