摘要
对实测地运动信号,分别应用短时傅里叶变换（STFT）、Wigner-Ville分布（WVD）、小波变换（WT）和Hilbert-Huang变换（HHT）进行了分析,讨论了地运动信号的时频分布。结果表明,地运动信号有多个中心频率,信号能量在0～30 Hz以内,优势频率在12～15 Hz。4种时频分析方法都能反映地运动信号的时频特征,STFT和WVD只能粗略反映信号能量的分布情况,可以给出能量峰值对应的具体时间和频率,但其分辨率单一。WT和HHT可以给出信号能量比较详细的分布情况,WT具有多分辨率特点,但给出的能量分布在一定的带宽内,不能给出某一频率的能量分布。HHT具有自适应性,给出的是某些特征分量的能量分布,也不能给出某一频率的能量分布。
An experimental recording signal of ground motion was analyzed by means of short time Fourier transform （STFT）, Wigner-Ville distribution （WVD）, wavelet transform （WT）and Hilbert-Huang transform （HHT）. The time-frequency distribution of the ground motion signal was discussed. The results show that the ground motion signal is composed of several frequencies, the energy of the signal lies in 0-30 Hz, and the dominant frequency is 12-15 Hz. By analysis, four means can all reflect the time-frequency characteristics of the signal, but STFT and WVD could only give a simple time-frequency distribution of the signal, the analyzed results from them with fixed window function and single resolving power can only give the time and frequency varied with signal energy peak values. WT and HHT can give a detailed timefrequency distribution, the analyzed results from WT with multi-resolving power can reflect the signal energy distribution varied with certain frequency band, however, the results can not reflect the signal energy distribution at a certain frequency. The analyzed results from HHT with self-adaptive characteristic can reflect the signal energy distribution varied with the intrinsic mode function, they also can not display the signal energy distribution at a certain frequency.
出处
《解放军理工大学学报（自然科学版）》
EI
2007年第5期546-550,共5页
Journal of PLA University of Science and Technology(Natural Science Edition)
