Chengdu University of Technology College of Engineering Technology;
Leshan 614000;
Sichuan;
China;
Southwest Institute of Physics;
Chengdu 610225;
China;
Chengdu University;
Chengdu 610106;
China;
Chengdu University of Technology;
Chengdu 610225;
China;
Fourier transform; Wavelet transform; Moving average; Kalman filter; Charge comparison method; Fractal spectrum method; Back-propagation neural network;