量子电子学报, 2008, 25 (5): 0619, 网络出版: 2010-06-07
OCDMA系统二维QPC地址码的设计和性能研究
Acquirement and performance analysis of 2D-QPC signature code for OCDMA system
光通信 光码分多址 光地址码 二维二次素数码 系统容量 误码率 optical communication optical code-division multiple access two-dimensional quadratic prime code one-dimensional synchronous quadratic prime code
摘要
通过对光纤信道波长片和时间片的重新组合,提出了一种新的适用于二维OCDMA系统的素数码(2D-QPC)的结构方案;给出了具体的码字设计步骤和过程;运用有限域理论,分析了码字的相关特性。在此基础上,根据“撞击法”研究2D-QPC应用于同步OCDMA系统时的用户容量和误码性能。结果表明:较之一维QPC,2D-QPC的相关特性有了很大的改进:最大自相关旁瓣由1降为0,最大互相关由2降为1;2D-QPC在系统容量上也有很大提高:在相同带宽,传输速率相同的情况下,比一维QPC的系统容量增加p+1倍。
Abstract
In both time and wavelength domains of the fiber-optic channels,a novel construction scheme of two-dimensional quadratic prime code(2D-QPC)for two-dimensional optical code-division multiple access system is proposed. The designing process of 2D-QPC is given in detail;the autocorrelation and crosscorrelation of 2D-QPC are analyzed based on finite Galois Theory. After that,the system capacity and BER performance of optical code-division multiple access(OCDMA)system employing 2D-QPC as signature code are calculated according to the“HIT”method. The result indicates that 2D-QPC has better auto and cross correlation properties compared to one dimensional synchronous quadratic prime code(1D-QPC)(autocorrelation from 1 to 0,cross-correlation from 2 to 1),and 2D-QPC also has larger system capacity,which is p+1 times as that of 1D-SQPC when they occupy the same bandwidth and have the same bit-rates.
李传起, 常建华, 张成义, 孙小菡. OCDMA系统二维QPC地址码的设计和性能研究[J]. 量子电子学报, 2008, 25(5): 0619. LI Chuan-qi, CHANG Jian-hua, ZHANG Cheng-yi, SUN Xiao-han. Acquirement and performance analysis of 2D-QPC signature code for OCDMA system[J]. Chinese Journal of Quantum Electronics, 2008, 25(5): 0619.