EEG time-frequency analysis based on the improved S-transform

S-transform, which is a combination of short-time Fourier transform and wavelet transform, has attract intensive interest in recent years as an important tool to investigate non-stationary signal time-frequency distribution. S transform can be self-improved by the EEG characteristics to select a suitable mother wavelet. The improved S-transform will be used to analyze the time-frequency of the EEG characters. A comparison among the Short-time Fourier transform, wavelet transformation and the improved S-transform indicates that improved S-transform gives the best energy distribution in the time-frequency filed.