QPSK是一种二维调制技术，其中水平轴称为同相轴，垂直轴称为正交轴，分别对应于星座图上的1和Q坐标。同相载波指载波本身，正交载波指相位旋转90度的载波1周。QPSK调制在实现时是采用正交调幅的方式，某星座点在1坐标上的投影去调制同相载波的幅度，在Q坐标上的投影去调制正交载波的幅度，然后将两个调幅信号相加就是所需的调相信号,QPSK is one kind of two-dimensional modulating technology, the horizontal axis is called the alignment, the vertical axis is called the normal axis, corresponds separately in the star map 1 and the Q coordinate. The synchronism carrier refers to the carrier itself, the orthogonal carrier refers to the phase rotation 90 degree carrier 1 week. QPSK modulation when realization is uses the orthogonal amplitude modulation the way, some constellation in 1 coordinate s projection demodulate synchronism carrier s scope, in the Q coordinate s projection demodulate orthogonal carrier s scope, then two amplititude-modulated signal adding together is the phase-modulated wave which needs