Abstract:In view of unsteadily flying, the helicopter brings about great errors to moving targets imaging, especially SAR imaging of moving ship. So this paper shows an effective method based on an idea that uses motion compensation, general second-step keystone transform twice and at the same time, finds an isolated point and adopts WVD transform to estimate Doppler parameters for removing range walk and curvature. And what is more, the detailed deductions are given in this paper.Finally, the SAR image of moving ship is acquired in the azimuth frequency field. The simulation results of three moving point-targets and the imaging result of real ship data confirme this method.