Constellation Receiver

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This block makes hard decisions about the received symbols (using a constellation object) and also fine tunes phase synchronization.

The phase and frequency synchronization are based on a Costas loop that finds the error of the incoming signal point compared to its nearest constellation point. The frequency and phase of the NCO are updated according to this error.

Const rcvr loop.jpg


constellation of points for generic modulation, see Constellation Object
Loop BW
Loop bandwidth of the Costas Loop. A good starting point is 2pi/100, or about 0.06.
Min Freq Deviation
minimum normalized frequency value the loop can achieve
Max Freq Deviation
maximum normalized frequency value the loop can achieve