海杂波FRFT域分形特征在动目标检测中的应用

Application of Fractal Character of Sea Clutter in FRFT Domain for Moving Target Detection

摘要:

文中研究了海上动目标雷达回波与海杂波在分数阶Fourier域(FRFT域)的分形特性,利用两者幅值起伏程度的不同,提出了一种基于FRFT域分形维数差异的动目标检测方法。该方法以处处连续而不可导的非平稳不规则信号模型——分数布朗运动作为FRFT域分形模型,通过仿真分析实测海杂波数据的分形曲线,证明海杂波在FRFT域的无标度区间内具有分形特性。提取出FRFT域海杂波与动目标回波的分形维数,并利用其固有的差异进行目标检测。经不同极化方式下海杂波数据仿真,验证了算法的有效性。

Abstract:

In this paper, a novel moving target detection method was proposed based on the fractal character differences of sea clutter in fractional Fourier transform (FRFT) domain. The fractional Brownian motion was employed for fractal model in FRFT domain. Simulations of fractal curves of real sea clutter were conducted, which indicated the fractal character within its corresponding scale-invariant interval. The intrinsic fractal dimension differences of sea clutter and the echoes from a moving target in FRFT domain were used for detection. Real sea clutter in different polarizations was used for verification and the results show the effectiveness of the algorithm.