PCM编码把模拟信号转换为数字编码，在通信电路的目的地，脉冲调制解调器将二进制的数字编码重新转换成那些在调制器中有相同量子水平的脉冲。-PCM encoding to convert analog signals to digital encoding, the destination of the communication circuit, the binary pulse modem re-converted into digital code modulator in which the

用matlab编写的模数转换和数模转换的仿真程序，写的比较浅显，可以辅助看一看。-Modulus using matlab convert digital to analog conversion of the simulation program, written in relatively plain, can assist a look.