102 Chapter 13 - Constellation diagram
10713 Vxx.11
Figure 13-3 Constellation diagram with phase jitter
Error phase jitter: The carrier is subjected to a low-frequency frequency modulation.
Cause: Defect or not correctly adjusted QAM modulator.
Figure 13-4 Constellation diagram with noisy signal
Error: noisy signal
Cause: bad C/N -> the level is possibly too low
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