“…HHT can process any signal without prior knowledge and is not be limited by the Heisenberg uncertainty principle. However, HHT also has some disadvantages, such as mode mixing, endpoint effect, instantaneous frequency error and so on [5]. The key part of the method is the empirical mode decomposition (EMD), which can decompose the signal into a finite number of intrinsic mode functions (IMF) in the temporal domain, with each IMF being a narrow-band signal [6,7].…”