A Spatial Variant Phase Compensation Algorithm for Bistatic ISAR Imaging of Maneuvering Targets Based on Optimal Parameter Estimation

When imaging a maneuvering target with complex three-dimensional (3-D) non-uniform rotational motion, the traditional range Doppler (RD) algorithm for bistatic inverse synthetic aperture radar (Bi-ISAR) will fail due to the presence of phase errors. Moreover, due to the time-varying property of the imaging projection plane (IPP), the phase errors are two-dimensional (2-D) spatial variant. In order to deal with these problems, we propose a spatial variant phase compensation (SVPC) method based on parametric minimun entropy optimization to compensate for the 2-D spatial variant phase errors. The main contribution of the proposed method is to give an accurate expression of the 2-D spatial variant model and optimally compensate the 2-D spatial variant phase errors in the Bi-ISAR configuration. Simulation results verify the effectiveness of the proposed algorithm.