摘要
针对高速铁路实测轨道振动加速度信号,对比了STFT、WVD和Gabor变换三种方法分析的时频特征,利用STFT分析结果提取出匀速条件下最不利长波不平顺波长;针对STFT时频分辨率受限的特点,提出改进方案;利用改进后的STFT分析了实测信号的时频特征。时频分析结果表明:高速铁路长波不平顺信号振动频率与列车速度呈单调递增关系;改进的STFT能够顺利提取长波不平顺信号特征频率。
The time-frequency characteristics of a vibration signal, measured on some high-speed railway, was given by short time Fourier transform（STFT）,Wigner-Ville distribution（WVD）and Gabor transform. The most disadvantage irregularity wavelength, under uniform conditions,was extracted by the result of STFT. Because of the contradiction between time and frequency resolution, an improved STFT was raised to analyze the time-frequency characteristics of the signal. The results show that the vibration frequency of long-wave irregularity is synchronized varying according to the train speed,and the improved STFT can successfully extract the long-wave irregularity characteristic frequency.
出处
《电子测量技术》
2009年第7期29-32,共4页
Electronic Measurement Technology
关键词
高速铁路
轨道不平顺
时频分析
短时傅里叶变换
high-speed railway
track irregularity
time-frequency analysis
short time fourier transform
