We present a computational approach to the imaging of a two-dimensional (2D) embedded perfectly conducting cylinder by the asynchronous particle swarm optimization (APSO). An embedded conducting cylinder of unknown shape scatters the incident transverse magnetic (TM) wave in a half space while 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 inverse problem is solved by an optimization approach and the global searching scheme, the asynchronous particle swarm optimization is then employed to search the parameter space. This method is tested by several numerical examples, and it is found that the performance of the APSO is robust for reconstructing the perfectly conducting cylinder. Numerical simulations show that even when the measured scattered fields are contaminated with Gaussian noise, the quality of the reconstructed results obtained by the APSO algorithm is very good.
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