Main Content

Plot Noisy QPSK Constellation

Apply QPSK modulation to a signal of random data. Pass the modulated signal through an AWGN channel. Plot the signal constellation.

The doc_qpsk_mod model. generates QPSK data, applies white noise, and displays the resulting constellation diagram.

Run the model with the Eb/N0 of the AWGN Channel block set to 15db.

Change the Eb/N0 from 15 dB to 10 dB. The noise level increases as shown by the greater distance between the samples.