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。

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.