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Wigner transform and continuous wavelet transform are both some kind of time-frequency representation of a signal.

What are the similarities and differences between them? Could you give some comparison between them? Let's restrict ourselves in 1D signal at the moment.

lennon310
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xslittlegrass
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    Wigner is not linear and involves a product that is roughly equivalent to the local autocorrelation, while a CWT is a linear operation. Wigner has cross terms, CWT doesn't. Both are time frequency representations but the limits of integration are minus infinity to plus infinity for a Wigner, which implies that Wigner is noncausal while CWT is causal. –  Jul 11 '17 at 20:19

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There is a nice tutorial: Time-Frequency Toolbox For Use with MATLAB tthat compares many transformations, notably continuous wavelet transform and Wigner and its avatars.

Basically, the CWT belongs to atomic linear representations (a decomposition onto wavelet atoms), while Wigner-Ville is an energy distribution (to split the energy of signals over time and frequency).

Since the tutorial comes with a toolbox and many examples, you can easily reproduce it on your signals.

Laurent Duval
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