随着相位编解码器关键技术的突破, 精确分析相位编码光码分多址(OCDMA)系统误码率性能显得十分必要。为了精确分析相位编码光码分多址系统误码率性能, 提出了一种基于判决变量的矩母函数和鞍点近似的非高斯近似方法, 该方法能够精确考虑多址干扰、散粒噪声、热噪声各自的统计特性和相互间的非加性关系。比较了高斯近似、精确计算和文中所提出方法在分析相位编码系统误码率时的计算精度和复杂度, 结果证明该分析方法具有分析精度高、计算复杂度低的优点。

With the key technologies breakthrough of phase encoding, it is necessary to analyze the bit error rate performance of phase encoding optical code division multi-access accurately. A non-Gaussian approximation method, based on the moment generation function of the decision statistic and saddle-point approximation, is introduced to evaluate the statistic characteristics of multi-access interference, shot noise and thermal noise and cross-correlation. Mumerical comparison between Gaussian approximation method, accurate calculation and non-Gaussian approximation method, proves the high accuracy and efficiency of the proposed method to analyze the bit error rate of the phase encoding system.