Yang Xiaoqi, Huo Kai, Su Jianwei, Zhang Xinyu, Jiang Weidong
Graduate School, National University of Defense Technology, Changsha 410073, China.
College of Electronic Science and Technology, National University of Defense Technology, Changsha 410073, China.
Sensors (Basel). 2020 Mar 14;20(6):1635. doi: 10.3390/s20061635.
Traditional constant false alarm rate (CFAR) methods have shown their potential for foreign object debris (FOD) indication. However, the performance of these methods would deteriorate under the complex clutter background in airport scenes. This paper presents a threshold-improved approach based on the cell-averaging clutter-map (CA-CM-) CFAR and tests it on a millimeter-wave (MMW) radar system. Clutter cases are first classified with variability indexes (VIs). In homogeneous background, the threshold is calculated by the student-t-distributed test statistic; under the discontinuous clutter conditions, the threshold is modified according to current VI conditions, in order to address the performance decrease caused by extended clutter edges. Experimental results verify that the chosen targets can be indicated by the t-distributed threshold in homogeneous background. Moreover, effective detection of the obscured targets could also be achieved with significant detectability improvement at extended clutter edges.
传统的恒虚警率（CFAR）方法已显示出其在检测外来物碎片（FOD）方面的潜力。然而，在机场场景的复杂杂波背景下，这些方法的性能会变差。本文提出了一种基于单元平均杂波图（CA-CM-）CFAR的阈值改进方法，并在毫米波（MMW）雷达系统上进行了测试。首先用变异性指标（VI）对杂波情况进行分类。在均匀背景下，阈值由学生t分布检验统计量计算得出；在不连续杂波条件下，根据当前VI条件修改阈值，以解决由扩展杂波边缘导致的性能下降问题。实验结果验证了在均匀背景下，所选目标可以由t分布阈值指示出来。此外，在扩展杂波边缘处，还能有效检测被遮挡的目标，显著提高检测能力。
