12-02-2020, 12:41 PM
(12-01-2020, 10:26 PM)Jens Noritzsch Wrote: The resolution in the autocorrelation graph corresponds to that of the sensor, so for iDevices it would be 100Hz, i.e. one dot each 10ms. The analysis algorithm looks out for the right most maximum and divides the time shift by the order of the maximum. This improves the resolution a bit to 10ms/order.
I performed a few tests and could definitely see a 10ms “grid” in 1/frequency, i.e. the period. The associated order of the dots in-between keeps me wondering a bit (in the final example one less than expected)…
Jens,
since I have few smartphones collecting dust..... My previous screenshots were from Samsung Galaxy S6 Active phone. I've tried that very experiment with Samsung Galaxy S8:
and with iPhone 6:
and the graph is exactly as you explained it should be! One can very clearly see the frequencies "grid" - although I see them spaced every ~0.005Hz
I suppose the 'extra' data points I'm seeing on my Samsung Galaxy S6 Active phone are due to some inaccuracies of that device sensor?