基于二次全等跳频码的跳频光码分多址系统

Novel Frequency-Hop Optical Code Division Multiple Access Based on Quadratic Congruence-Hop Codes

从跳频光码分多址(FH-OCDMA)系统的扩频特征出发,推导出具有良好相关性能的扩频码所能达到的最大码容量,再利用二次全等理论为跳频光码分多址系统构造出一种具有最大码容量的扩频码——二次全等跳频码(QCHC),并给出了构造实例。在此基础上,运用光纤布拉格光栅序列作为编解码器设计了一种跳频光码分多址系统的实现方案,并对该系统的性能进行了详细的分析。结果表明,采用二次全等跳频码的跳频光码分多址系统具有设计简单、用户容量大和误码率低等方面的优点。

A novel frequency-hop （FH） scheme is proposed for optical code division multiple access （OCDMA） system. According to the characteristics of FH-OCDMA system, an upper bound on the code size is deduced and the quadratic congruence-hop codes （QCHC） which achieves this bound is presented, with examples given. On the basis of it, a novel scheme for FH-OCDMA system with fiber Bragg grating array based encoder/decoder and QCHC is designed. Furthermore, a detailed performance analysis of the system is given. The results reveal that such a new scheme for FH-OCDMA system is not only easy to plan, but also has a large number of simultaneous users and low bit error rate.