MCZT在气枪震源信号频谱分析中的应用

Application of the Modified Chirp-Z Transform in SpectrumAnalysis of Air-gun Seismic Source Signals

摘要:

气枪震源信号是短时非平稳信号，采用频谱细化算法能提高频谱分析的准确性。首先进行了改进线性调频Z变换（MCZT）和FFT两种频谱分析算法的误差仿真计算，然后进行气枪震源的水下子波信号和地震波信号的对比计算。结果表明MCZT计算误差较小、计算时间较少，能有效提高气枪震源信号频率和幅度特征提取的准确性，是气枪震源信号频谱特征分析的一个有效方法。

Abstract:

The air-gun seismic source signal is a kind of short-time non-stationary signal, and the spectral zoom algorithm can improve the accuracy of the spectral analysis of such signals. In this study, the error simulation calculations of the two spectral analysis algorithms of a modified chirp-Z transform (MCZT) and fast Fourier transform (FFT) were carried out. Second, the underwater wavelet signal and seismic wave signal of the air-gun seismic source were calculated and compared. The results show that the MCZT algorithm has a smaller error and its computation time is less than that of the FFT. It can effectively improve the extraction accuracy of the frequency and amplitude feature of air-gun seismic source signals. This indicates that the MCZT algorithm is an effective method to analyze the spectrum characteristics of air-gun seismic source signals.