WiNRADiO G315 VHF/UHF Receiver
90
The CW received signals are first down-converted to zero Hz, and then, after
additional channel filtering, up-converted to a convenient audio frequency. This
frequency (a
digital BFO
) is user-adjustable, by changing the value of the
CW
tone frequency
parameter in the demodulator setup.
CW Demodulator Structure
Finally, the frequency demodulator performs a time derivative function on
arctangent of Q over I, to arrive at amplitude-independent frequency
demodulation of the input signal: