Does anyone know if the black box pingers stay phase stable? Its been mentioned before about folding data to get a better signal to noise. Its a common pulsar technique.
So I'm wondering as the battery weakens and the amplitude gets less, if they can just go to folding the signal on the pulse period. Of course if the phase is drifting significantly then thats not an option.
I presume if they are recording every thing then they would do that any way to bring out the pulse in the areas to produce some kind of spatial map of intensity.
Any one with an understanding of the acoustics side of things care to enlighten me?