（1）编程建立Gold序列，仿真Gold序列的波形； （2）仿真Gold序列的自相关和互相关特性。 （3）编程仿真直接扩频通信系统模型，画出扩频前后信号波形及频谱。((1) programming Gold sequence and simulating the waveform of Gold sequence; (2) the autocorrelation and cross correlation characteristics of the simulated Gold sequ