An efficient method is proposed in this paper to reconstruct the shape of a two-dimensional perfectly electrically conducting (PEC) target using limited scattered information. Based on the physical optics approximation, a Fourier transform relation has been obtained between the PEC target and the scattered fields. In theory, all scattered-field data are required for the reconstruction in the whole angle range (from 0 to 2π) and in the whole frequency range (from 0 to ∞). However, such data are impossible in practical applications. In this paper, we have discussed the influence of limited frequencies and limited incident angles on the imaging, where a Pade interpolation technique has been developed to obtain the scattered information in the whole angle range from limited-angle information. In order to overcome the ill-posed problem in the interpolation, the Tikhonov regularization has been used. Reconstruction examples are given to validate the efficiency of the proposed approach.
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