一种SAR/GMTI系统距离模糊杂波抑制方法

Range ambiguous clutter suppression for the SAR/GMTI system based on the frequency diverse array

针对星载广域高分合成孔径雷达地面运动目标检测系统脉冲重复频率较高时存在的距离模糊问题,提出了一种基于频率分集阵列的距离模糊杂波抑制方法.该方法利用各距离模糊区回波在发射空间频率域上相互分离的特点,设计一组滤波器分别提取各模糊区的动目标和杂波回波,并利用多个接收通道进行数字波束形成对各个距离模糊区分别完成杂波抑制.实验结果表明,该方法充分利用了系统通道数目资源,减弱了各模糊区杂波非均匀性的影响,实现了动目标回波无模糊重建,从而有效拓展了检测区域面积.

A range ambiguous clutter suppression approach based on frequency diverse array configuration is proposed to handle the range ambiguity of the space borne wide-swath high-resolution synthetic aperture radar ground moving target indication （SAR/GMTI） system with a high pulse repetition frequency. Since echoes from different ambiguous range regions are separable in the transmit spatial frequency domain, a filter bank is employed to extract echoes from each region, and then the transmit beam forming is implemented to suppress the clutter in each range region. Simulation results demonstrate that, by making full use of the limited channels, the proposed method could weaken the influence of heterogeneous clutter in each region and reconstruct moving target signals without range ambiguity, so as to expand the detection region evidently.