4 ms·
Most Bluetooth being GFSK means the TX chain is completely non-linear to begin with, so the frequency error is an easier target for fingerprinting. That said
by RF_Savage 2y ago
Most Bluetooth being GFSK means the TX chain is completely non-linear to begin with, so the frequency error is an easier target for fingerprinting.
That said, most also have ramp-up and ramp-down slopes on the transmission start and end to control and shape the spectral emissions.
So there might also be something to that.
Still a harder thing to fingerprint than frequency errors relating to transmit center frequency and baudrate.
- RachelF 2y agoIndeed. For most solid-state transmitters many of these non-linearities in envelope and frequency are temperature dependent too. The same device will give different signatures at different temps.