title: Hilbert–Huang transform: Instantaneous frequency
body: <p>I'm implementing the "Empirical Mode Decomposition" in Java. The next step is Hilbert–Huang 
  transform and I need to find how to get the "Instantaneous frequency". Does someone Know how to get it?</p>
  
  <p>Using the EMD method, any complicated data set can be decomposed into a finite and often small number of components, which is a collection of intrinsic mode functions (IMF). Next step is Hilbert–Huang transform. From this I calculate the signal's phase and after I must calculate the instantaneous frequency, I search in Matlab code like in this link: <a href="http://read.pudn.com/downloads100/sourcecode/math/408870/emd/instfreq/archive/ifreq.m__.htm" rel="nofollow">http://read.pudn.com/downloads100/sourcecode/math/408870/emd/instfreq/archive/ifreq.m__.htm</a></p>
  
  <p>but I don't understand it.</p>
  
  <p>Thanks</p>