The Research of Irregularity Power Spectral Density of Beijing Subway

This paper aimed to describe track irregularity of Beijing Subway. A preprocessing data that are from the upward track of Beijing Subway line 10 have been used in the survey. In addition, based on the maximum entropy principle, the spectrum of track irregularity power spectral density which is short for PSD has been drawn using MATLAB and fitted by using a nonlinear least squares method. After all scientific discussion, the results show the characteristic parameters of PSD. Furthermore, by contrasting Beijing Subway with national rail line, a proper function research has been done about track irregularity of Beijing Subway and the characteristics of track irregularity power spectral.