环形OCDMA系统中远近效应的研究  

Research on Near-far Effect in the Ring OCDMA System

作　　者：杨志程[1] 

机构地区：[1]桂林电子科技大学信息与通信学院,广西桂林541004

出　　处：《计算机仿真》2009年第4期138-140,共3页Computer Simulation

摘　　要：为了分析环形OCDMA系统性能,研究了OCDMA系统中的远近效应。首先分析了环形OCDMA系统中远近效应产生的原因,在考虑多址干扰和自环干扰的前提下,推导出在效应下系统的误码率(BER)表达式,并对远近效应对系统性能的影响进行了研究和仿真。仿真结果表明信噪比的提高可以减小远近效应,且系统中存在一个最佳接入用户数,当实际接入用户数大于最佳接入用户数时,系统误码率与耦合系数成反比,反之系统误码率与耦合系数则成正比。最后,给出两种有效减小远近效应的方法。For analysing the ring OCDMA system＇s performance, the near -far effect in the ring OCDMA system is investigated in this paper. The reason of near - far effect in OCDMA ring system is analyzed. Expression of BER of system under this condition is obtained and simulated. The simulation result indicated that the enhancement of the signal - to - noise ratio may reduce the near - far effect, and in the system there is a best access number of users. When actual access number of users is bigger than the best access number of users, the system error rate is proportional to the coupling coefficient, otherwise the system error rate is inversly proportional to the coupling coefficient. At last, tow methods of reducing the near - far effect are presented.

关 键 词：光码分多址 环网 误码率 远近效应 

分 类 号：TN929.11[电子电信—通信与信息系统]