Electromagnetic inverse scattering of rotating axisymmetric objects

The electromagnetic inverse scattering problem for rotating axisymmetric objects is studied. A modification of a previously proposed two-step algorithm is adopted to obtain the first solutions to the problems of interest. In the first step, the forward solver is employed assuming zero rotating speed and the geometric and dielectric parameters are reconstructed by minimizing the cost function. In the second step, the values from the first step are used to determine the rotating speed. Numerical results for this type of inverse problems are provided for the first time by considering test cases with rotating homogeneous sphere and torus. The two-step algorithm is compared against the general inversion algorithm that relies on global optimization considering all unknown variables simultaneously. It is demonstrated that the proposed algorithm outperforms the general inversion procedure for all speeds of practical interest. The results are analyzed for noisy data in the near-field and far-field.