Moving Target Detection with Modified Logarithm Background Subtraction and Its Application to the GF-3 Spotlight Mode
Moving Target Detection with Modified Logarithm Background Subtraction and Its Application to the GF-3 Spotlight Mode
复制标题
修正对数背景扣除运动目标检测及其在GF-3聚光模式中的应用
DOI：
10.3390/rs11101190
复制
发表时间：
2019
期刊：
影响因子：
5
通讯作者：
Lin Yun
中科院分区：
文献类型：
--
作者：
Shen Wenjie;Hong Wen;Han Bing;Wang Yanping;Lin Yun
星载聚束式合成孔径雷达模式以其高分辨率的特点备受关注，但利用该模式进行运动目标检测的研究较少。针对高分三号聚束合成孔径雷达(SLC)图像，提出了一种基于图像序列的改进对数背景差法检测地面运动目标。最初的对数背景差分方法是我们团队为机载合成孔径雷达设计的。它使用子孔径图像序列生成背景图像，然后利用图像序列减去背景来检测运动目标。将原算法应用于星载聚束式合成孔径雷达数据时，会出现较高的虚警问题。针对星载情况下目标的低信噪比造成的高虚警问题，提出了几点改进措施。首先，为了保留大部分的运动目标特征，采用低门限恒虚警率(CFAR)检测器进行粗检测。其次，针对粗检测中运动目标特征密度高于虚警的特点，采用改进的基于密度的spatial-clustering-of-applications-with-noise)聚类方法减少虚警。第三，由于真实的运动目标特征具有动态特性，利用卡尔曼跟踪器剔除残留的误检测。用实际数据对该方法进行了验证，结果也证明了该方法在高分三号和其他星载系统中的可行性。
Spaceborne spotlight SAR mode has drawn attention due to its high-resolution capability, however, the studies about moving target detection with this mode are less. The paper proposes an image sequence-based method entitled modified logarithm background subtraction to detect ground moving targets with Gaofen-3 Single Look Complex (SLC) spotlight SAR images. The original logarithm background subtraction method is designed by our team for airborne SAR. It uses the subaperture image sequence to generate a background image, then detects moving targets by using image sequence to subtract background. When we apply the original algorithm to the spaceborne spotlight SAR data, a high false alarm problem occurs. To tackle the high false alarm problem due to the target’s low signal-to-noise-ratio (SNR) in spaceborne cases, several improvements are made. First, to preserve most of the moving target signatures, a low threshold CFAR (constant false alarm rate) detector is used to get the coarse detection. Second, because the moving target signatures have higher density than false detections in the coarse detection, a modified DBSCAN (density-based spatial-clustering-of-applications-with-noise) clustering method is then adopted to reduce false alarms. Third, the Kalman tracker is used to exclude the residual false detections, due to the real moving target signature having dynamic behavior. The proposed method is validated by real data, the shown results also prove the feasibility of the proposed method for both Gaofen-3 and other spaceborne systems.