说明：  MATLAB代码生成Gold码、m序列并得到自相关、互相关函数。之后进行BPSK调制，验证扩频通信的错码率的降低。
(Gold code and m sequence are generated and autocorrelation and cross-correlation functions are obtained. Then BPSK modulation is carried out to verify the reduction of error rate of spread spectrum communication.)