分布式小卫星SAR系统地面运动目标检测方法

Ground Moving Target Indication for Distributed Small Satellite SAR Systems

本文研究了分布式小卫星SAR系统的地面运动目标检测(GMTI)方法,并解决了小天线带来的距离/多普勒模糊,以及超稀疏阵带来的高旁瓣问题.本文方法的主要思想是利用空时自适应处理(STAP)把地面运动目标谱与杂波谱分离开,然后再利用SAR成像处理对分离开的地面运动目标谱进行聚焦.针对超稀疏阵的高旁瓣模糊问题,提出通过导向扫描空时平面来克服盲速影响.

This paper investigates the approaches to ground moving target indication （GMTI） for distributed small satellite SAR systems. In particular, we focus on the processing approaches to resolving the range/Doppler aliasing caused by the small antennas of small SAR systems and the high sidelobes arising from the highly sparse satellite array. The key idea of this paper is to extract the space-time spectra of ground moving targets from the space-time plane by using a space-time adaptive processing （STAP） algorithm. Then conventional SAR imaging processing can be used to fully focus the extracted space-time spectra of ground moving targets. To overcome the “blind velocities” caused by the high sidelobes, an approach is suggested to scan the whole space-time plane with the array steering vector is suggested.