摘要
在一种新的实用瑞利衰落信道下,存在加性高斯白噪声,对直接序列扩频(DSSS)通信系统抑制码片内、外多径干扰的能力进行理论分析与计算机仿真。证实扩频通信系统在多径瑞利衰落信道中传输时能有效地克服多径衰落;在多径衰落信道较强的条件下,与提高扩频增益相比,增加扩频码的码长对于提高移动通信系统的抗多径衰落性能更加有效,但是扩频增益并非越高越好,需合理选取。
Firstly,the effects of multipath fading with time delay shorter or longer than one chip interval on direct sequence spread spectrum （DSSS） are mathematically and experimentally re- searched in multipath Rayleigh Fading channels. Secondly, under the software environment of MATLAB/Simulink, the relationship curves of the bit error rate （BER） and the signal-to-noise ratio （SNR） of DSSS communication systems are presented. Simulation results indicate that DSSS system can efficiently overcome multipath fading in multipath Rayleigh Fading channels. The spreading gain is not the higher the better, so that it must be chosen reasonably. In addi- tion, compared with improving the spreading gain, increasing the PN code length is more ef- fective on improving the anti multipath fading performance of the whole communication system.
出处
《广西科学》
CAS
2012年第4期341-344,共4页
Guangxi Sciences
基金
湖南省教育厅科研项目(09C1259)资助
关键词
通信系统
误比特率
扩频增益
多径衰落
communication systems, bit error rate （BER）, spreading gain, multipath fading
