constellation

Create a OQPSK modulator.

mod = comm.OQPSKModulator;

Determine the reference constellation points. The constellation that displays does not depict the IQ delay introduced by the OQPSK modulator.

refC = constellation(mod)

refC = 4×1 complex

   0.7071 + 0.7071i
  -0.7071 + 0.7071i
  -0.7071 - 0.7071i
   0.7071 - 0.7071i

Plot the constellation.

constellation(mod)

Change the phase offset for the modulated symbols. Plot the constellation to show the rotated constellation points.

release(mod)
mod.PhaseOffset = 45*pi/180; 
constellation(mod)

Create comm.PAMModulator and comm.PAMDemodulator System objects, and then calculate their ideal signal constellations.

Create modulator and demodulator objects.

mod = comm.PAMModulator;
demod = comm.PAMModulator;

Calculate the constellation points.

refMod = constellation(mod)

refMod = 4×1

    -3
    -1
     1
     3

refDemod = constellation(demod)

refDemod = 4×1

    -3
    -1
     1
     3

Verify that both objects produce the same points.

isequal(refMod,refDemod)

ans = logical
   1

Display the ideal signal constellation.

constellation(mod)