傅里叶变换、STFT和Gabor扩展以及小波变换这些传统的时频分析方法不能灵活选择基函数,从而难以准确分析具有较强频率局部特性的高频信号和具有较强时间局部特性的低频信号。该文首次引入基于四参数线性调频高斯基自适应信号时频分析方法,对地震波进行时频分析,同时还引入地震波的正弦自适应表示和小波自适应时频表示,并对这三种自适应时频分布的效果进行对比,研究表明基于四参数线性调频高斯基的自适应信号时频分析方法具有更好的精度,同时这种分解收敛的速度也是最好,计算量小。
Several methods are currently used in time-frequency analysis of earthquake waves, such as Fourier transform, STFT, Gabor transform and wavelet transform. However, the selection of base functions for these methods is limited. Parametric adaptive time-frequency technique, which adopts a method of parametric adaptive signal decomposition and a related parametric adaptive time-frequency distribution, is introduced firstly. Then, adaptive sine, Gauss, wavelet decomposition is also introduced. Through the comparison of these methods, it is shown that adaptive time-frequency analysis method with parametric Gauss function has relatively higher accuracy and efficiency.