I am trying to understand the QPSK fundamental and when I read that the phase shifts are 45°, 135°, 225°, and 315° in QPSK, I can not figure it out how.
In other word, I do not understand how the wave form creates 45°, 135°, 225°, and 315° angles. It seems to me they are 45°, 315° (Since falls in 4th quadrant), again 315° (same, since falls in 4th quadrant), and 45° (since falls in 4th quadrant).
Could you please help me to understand how to wave forms are forming 45°, 135°, 225°, and 315° angles?