Phase-shift keying (PSK) is a modulation process whereby the input signal, a binary PCM waveform, shifts the phase of the output waveform to one of a fixed number of states. The demodulation process can be divided into three major subsections, as

将 PCM 编码后的录音经过 16QAM 系统，试听不同信噪比下的录音-The recording PCM encoded through 16QAM system, listen to the recording of different SNR