密集光码分多址系统

基于一种新型光码分多址(OCDMA)的混合(DS/FH)编解码器,提出了多用户公用同一跳频(FH)码字但使用不同的直扩(DS)码字的密集光码分多址系统方案。在忽略噪声的情况下,采用随机过程理论对系统误码率进行了上线分析。分析表明,混合系统适于密集光码分多址通信,从而克服了单一(DS或FH)系统可用码字较少,不能承载多用户的问题。另外,还有效地解决了单一系统中存在的失配和群速度色散等问题。

Dense optical CDMA systems

Based on a novel hybrid DS/FH encoder/decoder, the case that there were n users employing the same frequency-hopping (FH) pattern but different DS code patterns was considered. On the condition that the impact of channel noises was neglected, the upper bound probability of error was evaluated based on the stationary random process theory. The results show that the hybrid system was suitable for dense optical CDMA communication, thereby, the problem that there are less available code sequences for multi-users is mitigated. Moreover, the problems such as the link-impairment, dispersion of group velocity, etc. in the pure (DS or FH) system can be solved effectively.