Divison of Imaging Intervals and Selection of Optimum Imgaging Time for Ship ISAR Imaging Based on Measured Data

In this paper an Inverse Synthetic Aperture Radar (ISAR) imaging algorithm for ship targets based on the division of imaging intervals and the selection of optimum time is proposed. The relative motion of a ship on the ocean wave can be broken into three components, namely pith, roll and yaw, which makes the Doppler frequency vary with the slow time. So during the whole slow time the echoes are not linear frequency modulation (LFM) signals any more. Under this condition the division of the imaging intervals and the selection of the optimum imaging time during the considered imaging interval are of great importance for ISAR imaging of ship targets. The imaging results of the measured data demonstrate the effectiveness of the proposed approach.