关键词: 逆合成孔径雷达, 低信噪比, Keystone变换

Abstract:

In the process of the ISAR data with a low input SNR when the target is flying smoothly, the conventional motion compensation method is no longer valid. In this paper, a new motion compensation method based on the Keystone transformation is proposed for dealing with the data with a low input SNR. The Keystone transformation is used to eliminate the effects of linear range alignment caused by the radial velocity of the target. By coherently accumulating the adjacent range profiles, the SNR is increased so that the envelope correlation and PGA algorithms can be applied to compensate the high order radial motion. The simulation results show that, for the process of the data with a low input SNR, the performance of the method proposed in this paper is better than that of the classical method, so that it is possible to increase the radar range at which targets can be imaged.

Key words: inverse synthetic aperture radar, low SNR, Keystone transformation