说明：  和HHT变换有关的快速傅里叶变换频谱，边际谱等的实现程序，已经无数次仿真实验验证其非常正确，对于初学HHT的很有用
(And the HHT transform the fast Fourier transform spectrum, marginal spectrum to achieve program has numerous simulation experiment verify its very useful for the beginner HHT.)