天基分布式雷达GMTI方法

A New GMTI Method of Space-Based Distributed Radar

小卫星分布式雷达具有很多优点,但由于平台速度高、天线面积小、超稀疏分布,给信号处理带来了近场、宽带、混合基线等问题.本文针对地面慢速目标检测(GM T I)提出一种非同时采样空时自适应处理方法,能够有效缓解近场、方位去相关等问题,并提出两种提高GM T I性能的方法,新方法对复杂地形的适应性大大提高,仿真结果证实了方法的有效性.

To obtain the ability of ground moving target indication （GMTI） with acceptable minimal detectable velocity （MDV） ,the distributed radar carried by a cluster of small satellites is a promising option. However the signal processing is a real challenge due to the difficulties of near field observation,wide band observation and phase coupling which are brought by the three-dimensional sparse distribution of the antennas. This paper studies these difficulties and proposes a new space-time adaptive processing （STAP） method. Using non-simultaneous space-time samples, the new method weakens the difficulties of near field and wide band observation effectively. Then two methods are proposed to improve the applicability for complex terrain. One method splits each receiving aperture into several subarrays and the other adjusts the PRF. Both can improve the signal-to-clutter-and-noise ratio （SCNR） evidently. Simulations show the validity of these methods.