Parameter Estimation of Ground Moving Targets Based on SKT-DLVT Processing

It is well known that the motion of a ground moving target may induce the range cell migration, spectrum spread and velocity ambiguity during the imaging time, which makes the image smeared. To eliminate the influence of these factors on image focusing, a novel method for parameter estimation of ground moving targets, known as SKT-DLVT, is proposed in this paper. In this method, the segmental keystone transform (SKT) is used to correct the range walk of targets simultaneously, and a new transform, namely, Doppler Lv's transform (LVT) is applied on the azimuth signal to estimate the parameters. Theoretical analysis confirms that no interpolation is needed for the proposed method and the targets can be well focused within limited searching range of the ambiguity number. The proposed method is capable of obtaining the accurate parameter estimates efficiently in the low signal-to-noise ratio (SNR) scenario with low computational burden and memory cost, making it suitable to be applied in memory-limited and real-time processing systems. The effectiveness of the proposed method is demonstrated by both simulated and real data.