Robotron Pty Ltd G5P 用户手册

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WiNRADiO G3XX User’s Manual
 
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: 
 
 
 
 
 
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