摘要
傅氏变换在频域有完全的局部化特性 ,但不含时域局部化信息 ,这为分析信号在某一时刻的信号特征带来不便。小波变换可对信号进行多尺度分析 ,容易提取信号特征。本文主要是用小波变换方法分析移频信号 ,并用不同的小波基对铁路移频信号进行了仿真 ,通过比较找到了合适的小波基 ,结合 FFT算法得到移频信号的有关参数 ,并在文末给出了一个成功分析的例子。这种方法优于在目前铁路中所用的分析方法 。
Fourier analysis is a mathematical technique for transforming our view of the signal from a time based one to a frequency based one. But in transforming to the frequency domain, the time information is lost. When looking at a Fourier transform of a signal, it is impossible to tell when a particular event took place. Wavelets can afford the ability to perform local analysis — that is, to analyze a localized area of a larger signal. Based on the time frequency localization character of wavelet transform, this paper presents the analysis method of railroad frequency shift signal. And with the help of FFT, a success example is given in this paper.
出处
《铁道学报》
EI
CSCD
北大核心
2000年第2期42-44,共3页
Journal of the China Railway Society
基金
863计划资助项目! (863- 30 6- ZD0 6- 0 3- 4 )
