Abstract:
The Empirical Mode Decomposition (EMD) developed by Huang etc.of the NASAis an advanced method for signal analysis,and its application scope is extremely widespread.It can effectively obtain the time-frequency characteristics of non-stationary signals.But there is an involved end issue in the course of getting two envelops of the data using spline interpolation. Several approaches for restraining the end effect were proposed,and all have a certain degree of restraint effect.However,it is a lack of a systemic and accurate evaluation for the performance of these approaches.In this paper,several commonly used restraining methods,which include Matching Extending,Mirror Extending,Symmetrical Extending,and Polynomial Fitting.These methods have been evaluated by a comparison of the respective Hilbert spectrum,mean error of the estimated average frequency curve and computation load.