基于高尺度分形差量的海杂波背景下小目标检测

Small Target Detection in Sea Clutter Based on Difference of High Scale Multifractal

为了降低复杂海情对海杂波背景下小目标检测的影响,提高微弱信号检测准确度,文中采用多重分形去势波动分析法分析了海杂波数据在高尺度条件下的分形特性,将分形尺度q扩展到[-30,30],对多重分形参数H(q)的估计进行了研究,得到了高尺度分形差量ΔH(q),分析了尺度q的选取对ΔH(q)的影响,提出了一种基于高尺度分形差量的海杂波中小目标检测方法。实验结果表明:IPIX海杂波数据的分形特性受到海情和雷达极性的影响,选择高尺度指数q时,所提方法能够有效地区分动目标与纯海杂波之间的分形差异性,降低海杂波背景下小目标检测对海情的依赖性,相较于单尺度去势波动分析检测方法,大部分海情的检测门限提高了40%以上,发挥了海杂波数据在高尺度多重分形上的优势。

To reduce the strongly dependencein of sea condition in the detection of the small target in the background of sea clutter and improve the accuracy of the detection,in this paper,the difference of high scale multifractal is applied to propose a new method of small target detection in sea clutter. At first,multifractal detrended fluctuation analysis method（ MF-DFA） is adopted to analyze the multifractal property of IPIX sea clutter. The multifractal parameter H（ q） is estimated to solve the detection of small target from sea clutter in different sea conditions in this paper. Then,determination method of the difference of high scale multifractal ΔH（ q） is given and influence of the different q on ΔH（ q） is also discussed. Results show that multifractal property of IPIX sea clutter is affected by sea conditions and radar polarizations. When there is small target in IPIX sea clutter on high scale,the relationships of multifractal parameter H（ q） and scale q can be similar to a tangent function. When select appropriate scate q of multifractal parameter,the difference between sea clutter and small tarfet can be enlarge. Compared with fluctuation analysis method,the difference of high scale multifractalimproves the detection threshold of small target detection in IPIX sea cutter.