摘要
Starting from the configuration of the optical prime code, a kind of key signature code for the optical code-division multiple access （OCDMA） system, based on the linear congruence theory in the finite Galois field, the correlation properties of the basic prime code, the extended prime code and the modified prime code are mathematically analyzed, the distribution of cross-correlation values is given and the overlap area of ＂1＂s in the case of periodically circularly shifting is indicated. It is mathematically demonstrated that the maximum cross-correlation of the basic prime code is 2, and that of the extended prime code and the modified prime code is 1. The integrated correlation analysis process is proposed. The signal-interfere ratio （SIR） and the BER performance of the systems employing different signature codes are calculated, respectively, and the performances of OCDMA systems employing different signature codes mode are compared.
围绕OCDMA系统的重要地址码类型——光素数地址码的结构模型,根据有限Galois域上的线性全等理论,系统分析了基本素数码、扩展素数码、修正素数码的互相关特性,指出码字中“1”位的重叠区域.具体给出基本素数码最大互相关为2、扩展素数码和修正素数码最大互相关为1的数学证明,并给出完整的的素数码相关性分析过程.在此基础上,计算基本素数码和扩展素数码的信号干扰比以及多址干扰误码率,并比较基于不同素数码的OCDMA系统的误码性能,给出定量比较结果.
基金
TheNaturalScienceFoundationofJiangsuHigherEducationInstitutions(No.04KJB510057).
