说明：  建立了直接序列扩频系统的matlab仿真模型，在信道中存在高斯白噪声和干扰的情况下，对系统的在不同扩频增益下的误码率性能进行了仿真及分析，分析了扩频码的自相关性、误码率、性噪比。
(A matlab simulation model of the direct sequence spread spectrum system, the existence of Gauss white noise and interference in the channel under the condition of the system in different spreading gain the BER performance of the simulation and analysis, analysis of PN code autocorrelation, BER, SNR)