基于Hurst指数差异的海面小目标检测

Small Target Detection in Sea Clutter Based on Hurst Exponent Difference

针对传统舰载雷达和岸基雷达很难检测出海杂波背景下小目标的现状,提出一种基于Hurst指数差异的方法来检测海杂波背景下小目标。该算法基于小波分析法:计算各种极化方式下不同距离门的海杂波的Hurst指数,分析发现距离门含有小目标的Hurst指数明显大于距离门只含有海杂波的Hurst指数,而只含有海杂波的不同距离门间Hurst指数变化较小,因此可基于不同距离门的Hurst指数差值作为检测小目标的标准。实验证明,该算法可在没有任何先验知识条件较准确地检测出海杂波背景下的小目标。

Aiming at the present issue that small target detection in sea clutter is very difficult for tradi- tional shipborne and coast-sited radar, this paper presents a small target detection method based on different Hurst exponents. This method builds on the wavelet algorithm：by calculating the Hurst exponents（HEs） of different range bins with various polarizations and systematically studying many sea clutter datasets, it is found that the HE of the range bin hosting a small target（RBHST） is obviously much larger than that of oth- er range bins hosting only sea clutter（ORBHSC）. The HE of the primary target range is a little larger than that of secondary target ranges, while the HEs of ORBHSC are fairly close to each other, so the difference of HEs can be derived to detect small target. Besides, it is noted that the HEs of HV and VH polarizations are approximately the same. The experiments indicate that this method can be applied to detect small target in sea clutter accurately without prior knowledge of ocean conditions.