Quadrature Phase Shift Keying (QPSK) is a form of Phase Shift Keying in which two bits are modulated at once, selecting one of four possible carrier phase shifts (0, 90, 180, or 270 degrees). QPSK allows the signal to carry twice as much information as ordinary PSK using the same bandwidth.
HEMANT GHUGE (2019). QPSK-using-MATLAB (https://www.github.com/HemantGorakshGhuge/QPSK-using-MATLAB), GitHub. Retrieved .