The detection of railway frequency-shift signal mainly adopts the time-frequency analysis methods including the short time Fourier transform, wavelet transform, Wigner-Ville distribution, generalised s-transform and so on at present, however they all have the limitations and shortages to certain extent. In light of the problems these methods have, in this paper we improve the window function on the basis of original generalised S transform, its complexity is simplified as well. By applying the improved algorithm in the detection of railway frequency-shift signal, it can overcome the shortcomings of conventional time-frequency analysis methods, thus can detect every frequency characteristic of the frequency-shift signals accurately, and reduces the detection deviation significantly. The improved algorithm has important guiding significance in further research on frequency-shift signal detection methods and the development of frequency-shift signal detector with high-precision.%目前,对于铁路移频信号的检测主要采用短时傅立叶变换、小波变换、Wigner-Ville分布以及广义S变换等时频分析方法,以上方法都存在一定的局限和不足.针对以上各种方法所存在的问题,在原广义S变换的基础上对其窗函数进行改进,简化算法的复杂性.将改进算法用于铁路移频信号的检测中,可以克服常规时频分析方法存在的不足,从而准确地检测出移频信号的各个频率特征,明显地降低检测误差.改进算法对进一步研究移频信号检测方法及研制高精度的移频信号检测器具有重要的指导意义.
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