The error analysis model of sampling system was set up for the first time , by combining the saddlepoint approximation analysis and numerical arithmetic , which greatly increased the potential of further application and improved the reliability of the error approximation of the optical sampling histogram 论文首次建立了采用鞍点近似法与数值算法相结合的取样系统误差分析模型,大大扩展了鞍点近似算法的适用范围,提高了误码率估算的可靠性。论文提出了基于时分取样方法的光子模数转换。