说明：  设计一个有干扰的直接序列扩频通信系统， PN码由m序列产生器产生，经过高斯白噪声信道。在接收端接收到的信号包括“有用信号+高斯白噪声+干扰”，将接收信号进行解扩，判决，得到用户的信号检测结果，绘制不同的扩频增益（增益值为10，30，50）下，误比特率随信噪比Eb/N0的变化曲线。
(Design of a direct sequence spread spectrum interference system, PN code generated by the m sequence generator, after white Gaussian noise channel. Receives the signal at the receiver, including " useful signal+ Gaussian white noise+ interference" , will receive the signal despreading, judgments, get the user' s signal test results, draw a different spreading gain (gain value of 10,30, 50), the BER curves with the signal to noise ratio Eb/N0.)