Some studies on the effect of resolution with different ISAR imaging techniques

Inverse synthetic aperture radar (ISAR) imaging is used to produce high resolution images of moving targets from long distances which is used for automatic target recognition. Although the principle is same for a ship target on the sea and that of flying target in the sky, the former usually have more complex motions than the latter which makes the motion compensation very difficult [1]. However the change in phase chirp rate caused by complex motions of ship will deteriorate the azimuth focusing quality. In this paper, imaging of a target is shown for different ISAR techniques like Range Doppler, Range instantaneous Doppler and Range instantaneous chirp. The paper is organized as follows. In Section-I, an Introduction to ISAR imaging of ship target with motions is given. In Section-II the imaging techniques of the target with motion is given with necessary mathematical expressions. In Section-Ill the simulation results are shown. In Section IV finally the conclusion is explained.