混沌干扰中基于同步挤压小波变换的谐波信号提取方法  

Harmonic signal extraction from chaotic interference based on synchrosqueezed wavelet transform

作　　者：汪祥莉[1,2] 王斌[3] 王文波[4] 喻敏[3,4] 王震[3] 常毓禅 

机构地区：[1]武汉理工大学计算机科学与技术学院,武汉430063 [2]国家海洋局第二研究所,卫星海洋环境动力学国家重点实验室,杭州310012 [3]武汉科技大学信息科学与工程学院,武汉430081 [4]武汉科技大学信息与计算科学系,武汉430065 [5]中国人民大学财政金融学院,北京100872

出　　处：《物理学报》2015年第10期11-20,共10页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:11201354);卫星海洋环境动力学国家重点实验室开放基金(批准号:SOED1405);冶金工业过程系统科学湖北省重点实验室开放基金(批准号:Z201303)资助的课题~~

摘　　要：针对混沌干扰背景下多个谐波信号的提取问题,提出了一种基于同步挤压小波变换(SST)的谐波信号抽取方法.首先利用SST将混沌信号和谐波信号组成的混合信号分解为不同的内蕴模态类函数,然后利用Hilbert变换对分离出的内蕴模态类函数进行频率识别,从中分离出各谐波信号.以Duffing混沌背景为例,对混沌干扰下多谐波信号的提取进行了实验分析.实验结果表明:对于不同频率间隔的多个谐波分量,本文方法的提取结果都具有较高的精度,而且所提方法对高斯白噪声的干扰具有较好的鲁棒性,综合提取效果优于经典的经验模态分解方法.Extracting the harmonic signal from the chaotic interference background is very important for theory and practical application. The wavelet transform and empirical mode decomposition （EMD） have been widely applied to harmonic extraction from chaotic interference, but because the wavelet and EMD both present the mode mixing and are sensitive to noise, the harmonic signal often cannot be precisely separated out. The synchrosqueezing wavelet transform （SST） is based on the continuous wavelet transform, through compressing the time-frequency map of wavelet transform in the frequency domain, the highly accurate time-frequency curve is obtained. The time-frequency curve of SST which does not exist between cross terms, can better improve the mode mixing. The SST has also good robustness against noise. When the signal is a mixed strong noise, the SST can still obtain the clear time-frequency curve and approximate invariant decomposition results. In this paper, the SST is applied to the multiple harmonic signal extraction from chaotic interference background, and a new harmonic extracting method is proposed based on the SST. First, the signal obtained by mixing chaotic and harmonic signals is decomposed into intrinsic mode type function （IMTF） by the SST. Then using the Hilbert transform the frequency of each IMTF is analyzed, and the harmonic signals are separated from the mixed signal. Selecting the Duffing signal as the chaotic interference signal, the extracting ability of the proposed method for multiple harmonic signals is analyzed. The different harmonic extraction experiments are conducted by using the proposed SST method for different frequency intervals and different noise intensity multiple harmonic signals. And the experimental results are compared with those from the classical EMD method. When the chaotic interference signal is not contained by noise, the harmonic signal extraction effect is seriously affected by the frequency interval between harmonic signals. If the harmonic frequency interval b

关 键 词：同步挤压小波变换 混沌干扰 谐波提取 

分 类 号：O415.5[理学—理论物理] TN911.7[理学—物理]