One or Two frequencies? The Synchrosqueezing Answers

The synchrosqueezed transform was proposed recently in [Daubechies et al. (2009)] as an alternative to the empirical mode decomposition (EMD) [Huang et al. (1998)], to decompose composite signals into a sum of “modes” that each have well-defined instantaneous frequencies. This paper presents, for synchrosqueezing, a study similar to that in [Rilling and Flandrin (2008)] for EMD, of how two signals with close frequencies are recognized and represented as such.