摘要
以直接序列扩频(DSSS)通信系统为研究对象,在MATLAB/Simulink软件环境下分析了DSSS信号在多径瑞利衰落信道中传输时的抗多径衰落性能。采用Simulink软件构建DSSS通信系统的动态模型并进行仿真;研究了扩频增益、PN码码长、多普勒频移等特性,给出了DSSS通信系统误码率与信噪比(SNR)的关系曲线,进而掌握了多径瑞利衰落信道对DSSS信号传输的影响。仿真结果表明,在多径瑞利衰落信道下,DSSS通信系统能够有效地克服多径衰落和多普勒频移,但仍然存在一定的局限性。此外,与提高扩频增益相比,增加PN码的码长对于提高整个通信系统的抗多径衰落性能更加有效。
With the communication systems of direct sequence spread spectrum （DSSS） as the study object, the anti multipath fading performance of DSSS signals transmitted over multipath Rayleigh fading channel is analyzed under the software environment of MATLAB/Simulink. The DSSS communication system is dynamically modeled and simulated with Simulink. The characteristics of spreading gain, pseudo noise （PN） code length and Doppler frequency shift are analyzed, the relationship curves of the bit error rate （BER） and the signal-to-noise ratio （SNR） of DSSS communication systems are presented, and the influence of multipath Rayleigh fading channel on DSSS signal transmission is introduced. Simulation results indicate that the DSSS system can efficiently overcome multipath fading and Doppler frequency shift in multipath Rayleigh fading channels, although some limitations still exist. In addition, compared with improving the spread spectrum gain, increasing the PN code length is more effective on improving the anti multipath fading performance of the whole communication svstem.
出处
《信息与控制》
CSCD
北大核心
2009年第3期337-341,348,共6页
Information and Control
基金
仪器科学与动态测试教育部重点实验室基金资助项目(9140C1204020608)
关键词
直接序列扩频(DSSS)
多径衰落
信噪比(SNR)
误码率
扩频增益
direct sequence spread spectrum （DSSS）
multipath fading
signal-to-noise ratio （SNR）
bit error rate （BER）
spreading gain
