Weak target detection based on fractal analysis under rada sea clutter background is an open problem. The existing methods, using single fractal dimension and Hurst exponent in time domain or Fourier domain, are not applicable under low signal‐to‐clutter ratio (SCR) conditions. Since autoregressive (AR) spectrum has the advantage of high‐frequency resolution over the Fourier spectrum in sea clutter analysis, while multifracal theory is an extension of single fractal analysis. Therefore, we combined the multifractal analysis with AR spectrum estimate theory. Since singularity intensity function is an important parameter to describe a multifractal set, this paper proposed a weak target detection method based on singularity intensity function of AR spectrum under the sea clutter background. Then real S‐band data sets are used to analyze the singularity intensity function of AR spectrum, and the results show that the AR singularity intensity function between sea clutter and targets has different value range interval. Finally, the singularity intensity function width of AR spectrum is taken as a statistical test for weak target detection. Compared to the existing fractal methods method, the proposed target detection method improves the detection probability over 20% in low SCR condition.

中文翻译：

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自回归谱奇异强度函数分析及其在海杂波背景下弱目标检测中的应用

在雷达海杂波背景下基于分形分析的弱目标检测是一个未解决的问题。现有的在时域或傅立叶域中使用单一分形维数和Hurst指数的方法不适用于低信杂比（SCR）条件下。由于自回归（AR）谱在海杂波分析中比傅立叶谱具有高频分辨率的优势，而多谱理论是单分形分析的扩展。因此，我们将多重分形分析与AR谱估计理论相结合。由于奇异强度函数是描述多重分形集的重要参数，因此本文提出了一种基于海浪背景下AR光谱奇异强度函数的弱目标检测方法。然后使用真实的S波段数据集分析了AR谱的奇异强度函数，结果表明，海杂波与目标之间的AR奇异强度函数具有不同的值范围间隔。最后，将AR谱的奇异强度函数宽度作为弱目标检测的统计检验。与现有的分形方法相比，本文提出的目标检测方法在低SCR条件下的检测概率提高了20％以上。