基于小波变换模极大的爆破震动信号奇异谱分析

The singular spectrum analysis of blasting vibration signal based on WTMM

系统论述了基于小波变换模极大(WTMM)的多分形奇异谱计算方法。利用此方法对某一典型的岩石爆破震动信号进行分析,给出了分段函数Z(q,a)、尺度指数τ(q)以及奇异谱f(α)的分布曲线,说明了信号的多分形特征,认为信号的突变主要集中在α<1的奇异指数上,而信号的奇异指数也主要集中在0.28～0.72之间;并提出了对于岩石爆破震动信号几乎是处处奇异的重要结论。

Blasting vibration signal is very irregular and nonlinear and it is very important to analyze its multi-fractal spectrum (singular spectrum). However, the analysis will be inaccurate and incomprehensive if only part of the fractal dimensions is taken into account. In this paper, the method of singular spectrum based on wavelet transform modulus maxima (WTMM) is discussed, and by this method a typical blasting vibration signal has been analyzed. The partition function Z(q,a), scaling exponent τ(q) and singular spectrum f(α) are computed and their variation are presented. At the same time, the multi-factal features of the signal are discussed. The sudden changes of the signal are found to occur mainly on α<1, and the singular exponent α of the signal ranges from 0.28 to 0.72.