The application of mirror closed endpoint continuation upon restraining endpoint effect

In the process of Hilbert-Huang transformation, the empirical mode decomposition has been used. Through cubic spline interpolation, the obtained envelope curve will be diverged at ends of data, this is endpoint effect. According the method of mirror closed endpoint continuation signal can be mirrored into a kind of annular signal. The obtained signal has no end, however it has accurate period. Thus the corresponding endpoint effect can be restrained in the process of empirical mode decomposition and Hilbert transformation.