Novel approach for ISAR imaging of maneuvering targets

For the targets whose maneuverability is not too severe, the azimuth echoes in a range bin are modeled as quadratic phase signal after the translational motion compensation. The FrFT algorithm can obtain a focused image by motion parameter estimation and compensation. However, when a range cell contains more than one scatterer, the effects of sidelobes and interference terms will deteriorate the performance of FrFT method. To solve this problem, we add a selecting step for range cells in the imaging scheme. By selecting the dominant-scatterer range cells the estimation performance can be improved obviously. The effectiveness of the proposed method is illustrated and analyzed with simulations data.