I would like to find a way to identify whether some components of a signal I have are "noise components" or not.
Given the fact that the (normalized) autocorrelation function of white noise is a Dirac delta function in zero, would it be a good measure of noisiness the time-lag at which the autocorrelation function first crosses the lag-axis (at positive lags?) Or would you suggest another indicator?
I see that if signals are "not noisy", the zero-crossing time lag of the ACF gets bigger, as it should be. I attach a picture to express this concept.
Thanks for the tip. Regards,
E.