在机载合成孔径雷达(SAR)动目标检测中,由于地面慢速运动目标速度较小,因此很容易被地面强主瓣杂波淹没而检测不到。文中针对地面慢速运动目标的运动特点,提出基于分数阶傅里叶变换(Frft)的DPCA鄄CFAR 联合检测的方法,在采用天线相位中心偏置(DPCA)技术进行杂波抑制的基础上进行恒虚警(CFAR)处理,从而检测到运动目标,并且根据DPCA 对消后的信号幅度和CFAR 检测门限推导了最小可检测速度,说明了提出的算法对慢速运动目标的检测性能,并进一步采用Frft 方法估计出目标速度,最后通过仿真对算法的有效性进行了验证。

In airborne SAR moving target detection, ground slow moving target's speed is small, so it's easy to be submerged by ground strong main lobe clutter and undetectable. In this paper, according to the characteristics of the movement of ground slow moving targets, a DPCA-CFAR joint detection method based on Frft is proposed. After using DPCA to achieve clutter suppression, CFAR processing is made to detect the moving targets. And according to the signal amplitude after DPCA and CFAR detection threshold, the minimum detectable velocity is inferred to show the performance of this proposed algorithm for slow moving targets detection. Further Frft is used to estimate the target speed. Finally the effectiveness of the algorithm is verified by simulation.

TN957