基于扩展的双曲同余码/素数码的二维光正交码  

A New Two-Dimensional Optical Orthogonal Codes Based on Extended Hyperbolic Congruence Codes/Prime Codes

作　　者：吉建华[1] 范戈[1] 

机构地区：[1]上海交通大学区域光纤通信网与新型光通信系统国家重点实验室,上海200030

出　　处：《上海交通大学学报》2002年第12期1765-1769,共5页Journal of Shanghai Jiaotong University

摘　　要：构造了一种扩展的双曲同余码 ( EHC) ,用该码作为时间扩频伪随机序列和以素数码 ( PC)作为波长跳频伪随机序列 ,形成了一种新的二维光正交码 EHC/PC.与 EQC/PC相比 ,两者的码字数相同 ,互相关性能相当 ,但前者扩频系数和码重较小 ,可以提高用户的数据速率并降低对光编 /解码器的要求 .模拟计算表明 ,当同时使用的用户数较少时 ,EQC/PC的误码率比 EHC/PC略低 ;当同时使用的用户数中等或较多时 ,两者的误码率性能相当 .因此 ,EHC/PC比 EQC/PC更适合于同时使用的用户数中等或较多的光码分多址 ( OCDMA)系统 .A new one-dimensional optical orthogonal codes(1D-OOC), named extended hyperbolic congruence codes (EHC), was first constructed, and its performance was analyzed. Using the EHC for time spreading and prime codes (PC) for wavelength hopping, a new two-dimensional optical orthogonal codes(2D-OOC) named EHC/PC was constructed. Then, the performance of EHC/PC was analyzed, and also compared with EQC/PC. It is shown that EHC/PC has the same code cardinality and comparable cross- correlation performance, but has shorter code length and smaller code weight which can enhance user data rate and also reduce the complexity of optical encoders/decoders. The simulation analysis shows that, EQC/PC performs a little better than EHC/PC when the traffic load is light, but both have comparable performance for medium or heavy traffic. Therefore, EHC/PC is more suitable for optical CDMA networks with medium or heavy traffic.

关 键 词：光码分多址 二维光正交码 素数码 双曲同余码 OCDMA系统 地址码 跳频伪随机序列 

分 类 号：TN929.11[电子电信—通信与信息系统]