The NUFFT-based algorithm for 3-D near-field ISAR imaging

This paper presents a new three-dimensional (3-D) near-field synthetic aperture imaging technique based on the nonuniform fast Fourier transformation (NUFFT). A 3-D ISAR image can be obtained by processing coherently the backscattered fields as a function of the frequency and two rotation angles about axes which are mutually orthogonal. Comparisons of the NUFFT-based technique and the Cartesian tomography-based technique are demonstrated by means of numerical simulations. The simulation results demonstrate the proposed algorithm has the advantage of better reconstruction accuracy compared to the Cartesian tomography-based method.