基于改进匹配追踪算法的化爆地震波信号时频特征提取

通过化爆地震波信号的时频分析可以获取丰富的地下岩层信息，为进一步的化爆地震波特性研究提供支撑。本文中利用爆炸地震波信号的非平稳随机特性，提出一种改进的匹配追踪算法(matching pursuits)，该方法能更有效地获取化爆地震波信号的时频信息。该算法首先对地震波信号进行Hibert变换，将其转换成复数信号，获得爆炸地震波信号瞬时频率相位参数，再进行子波分解，从而显著提高了匹配追踪算法的运算速率；用分解后的信号计算其魏格纳威利分布(Wigner Ville distribution)，有效地消除了交叉干扰项的影响。将该方法用于实测地震波信号的时频分析，获得了分辨率较高的时频分布图，且运算速率大大提高。

Time-frequency analysis of explosion seismic signal based on improved matching pursuit

Abundant underground rock information can be obtained through the analysis of time-frequency of explosive seismic wave signals,which lays a foundation for further research on characteristics of explosive seismic waves.In this study,based on the non-stationary random nature of the explosive seismic signals,we presented an improved matching pursuits (MP) algorithm to extract the time-frequency information of explosive seismic signals,namely using the Hilbert transformation to convert the signal into a plural signal to acquire the instantaneous frequency and phase parameter of the signal and then decomposing the signal to a series of wavelets.Thus the operation rate was significantly improved and the Wigner Ville distributions (WVD) and its time frequency were calculated with the influence of the cross interference term effectively eliminated.This method has been used to take a time-frequency analysis of an actual explosive seismic wave signal and has acquired a time-frequency distribution with a high resolution and operation rate.