Study On The Ground Moving Target Detection And Parameter Estimation For Airborne Squint Synthetic Aperture Radar

In recent years, squint synthetic aperture radar (SAR) has become one of hot points inSAR research, because of the flexibility of beam pointing, it can revisit the hotspotsrepeatedly, and make real-time reconnaissance and combat in military. Ground movingtarget indication (GMTI) is one of the main functions of radar, in the fast-changingmodern war, through monitoring the mass moving targets that exist in the battlefield, hasan important strategic significance. So study the signature of ground moving target forairborne squint SAR, and how to detect the ground moving targets effectively, has a wideapplication prospects.In this paper, the topic of moving target detection and parameters estimation forairborne squint SAR is studied, on the foundation of the former research, put forwardsome new ideas of moving targets detection and parameter estimation, the main contentsare as follows:Firstly, based on the echo signal model of moving targets for squint SAR, derives theimage signature of the ground moving targets after the processing of Range-Doppler (RD)algorithm, including the geometry correction, the offsets and defocusing in both range andazimuth direction. The research results are especially significant for moving targetsdetection and parameters estimation in squint mode SAR.Secondly, based on the single channel SAR system, studies a moving targetsdetection method, which uses sub-aperture to realize. First, analyzes the principle of usingsub-aperture to detect moving targets in squint SAR mode, and derives the theoryprocesses. On the basis of realization of clutter suppression, a new parameters estimationmethod is then put forward. In addition, by stacking the moving targets that have beendetected, we can obtain the imaging trajectory of moving targets in airborne squint SAR.Finally, based on the multi-channel SAR system, studies a method of dual-channelmoving target detection, which on the basis of clutter suppression interferometry (CSI) ofside looking SAR, the echo signal of dual-channel squint SAR is built firstly, then, derivesthe principle of this moving targets detection method in detail, and the detection flow chart is given. Theoretical analysis and computer simulation show that this technology candetect the moving targets efficiently.