Nyquist Sampling Rate
To digitise an analogue avionics signal without aliasing, the sampling rate must be at least twice the highest frequency present.
Formula
Variables
Example
Audio to 3.4 kHz: f_s ≥ 6.8 kHz (voice comms sample at 8 kHz)
Did You Know?
Digital flight-data recorders and fly-by-wire buses sample well above Nyquist and add anti-alias filters, so high-frequency noise can never masquerade as a valid signal.
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