【摘要】 地震信号属于非平稳信号,常规傅立叶变换方法不能刻画任一时刻的频率成分,无法对其进行全面的分析。时频分析方法将一维时域信号变换到二维的时频平面,全面反映地震信号的时频联合特征。本文介绍了短时傅立叶变换、连续小波变换、Wigner-Ville分布、Cohen类分布四种时频分析方法,通过理论合成信号试算,从时间分辨率、频率分辨率,以及对多频率成份信号适应能力等方面阐述了这四种方法的优缺点,进一步分析比较了这四种方法的特点及应用效果。更多还原

【Abstract】 The seismic data usually is non-stationary signal,so the Fourier transform can not show the news of frequency at anytime and the seismic data can not be analyzed comprehensively.Time-frequency analysis methods transform 1D time domain signal into 2D time-frequency domain plane,and describe the joint time-frequency characteristics of the seismic data.This paper introduces four methods of time-frequency analysis,such as short time Fourier transform,continuous wavelet transform,Wigner-Ville distribution and Cohen class distribution.This paper explaios the merits and defects of the methods from the time resolution,frequency resolution and the adaptive ability of multi-frequency signals.Moreover,this paper explains the traits and the applications of some methods further by some academic synthetic signal test.更多还原