摘要
在MATLAB平台上,对直接序列扩频系统进行仿真分析。系统采用Hadamard序列作为扩频码,对系统在平坦衰落和瑞利衰落信道环境下的误码率进行分析,讨论了扩频、解扩过程。此外,还仿真比较了不同用户数和不同扩频码的系统,为分析设计直扩系统提供依据。仿真结果表明,本实验系统可在SNR为-1.6dB的传输条件下得到10-3量级的误码率,Hadamard序列可用作扩频序列,系统可用作检验各种正交码组的正交性。
In this paper, the direct sequence spread spectrum system is simulated by MATLAB. The Hadamard sequence as PN code and bit error rates over AWGN, multipath Rayleigh fading channel is used. The simulation results and the detailed process of spreading are presented. Further more, the systems with different users and PN codes are simulated. These results greatly contribute to designing the direct sequence spread spectrum communication system. The simulation results indicate that the spread spectrum system reaches 10^-3 bit error rates if the SNR around - 1.6dB. The Hadamard sequence can be used as PN code. The system can verify the orthogonality of PN codes.
出处
《信息技术》
2008年第1期127-130,132,共5页
Information Technology
关键词
直接序列扩频系统
哈达码
瑞利衰落信道
CDMA
direct sequence spread spectrum
Hadamard
muhipath Rayleigh fading channel
CDMA
