α稳定分布下信号的维格纳分布分析方法

摘要

It is not enough that only using a dimension analysis method for non-stable signal in alpha stable distribution noise, and it can need a two-dimensions time-frequency one. In the analysis of the existing time-frequency analyzing method, it found that the signal of background noise was assumed Gaussian distribution, so the performance of the time-frequency domain analysis for signal of noise in such non-Gaussian distribution as FLOA was in severe degradation. Focus on this problem, this paper proposed a novel Wigner-Ville distribution analysis method of fractional lower-order alpha stable distribution based on conventional Wigner-Ville distribution. Simulations show that the proposed method has more excellent performance than conventional Wigner-Ville distribution in time-frequency analyzing of alpha stable distribution process and is a new one in time-frequency domain research of alpha stable distribution.%研究分数低阶α稳定分布(FLOA)噪声下的信号仅从频域分析是不够的,需要考虑时—频域的二维信息.从现有的时—频分析方法发现,该方法是假设信号的背景噪声服从高斯分布,对FLOA这类非高斯分布噪声下信号的时—频分析性能退化严重.针对这一问题,在基于频域的FLOA分析理论上,将频域推广到时—频域的维格纳分布(WVD),提出了分数低阶WVD分析方法.计算机仿真测试结果表明,该新的WVD分析方法能在时—频域有效分析出FLOA的时—频分布特征,成功地使FLOA分析方法从频域拓展到时—频域.