数值仿真分析了利用高非线性光纤(HNLF)的交叉相位调制(XPM)效应实现归零(RZ)码到非归零(NRZ)码的转换，并讨论了RZ信号占空比、光纤色散对转换后NRZ信号Q因子的影响。数值结果表明：转换后NRZ码的Q值受输入RZ信号占空比的影响；而且RZ信号与连续的探测光之间的色散差也严重影响转换后NRZ信号的Q因子值。

We numerically analyze all-optical RZ to NRZ format conversion based on the Cross-Phase Modulation (XPM) in Highly Nonlinear Fiber (HNLF) and discuss the duty cycle of the RZ signals and the effects of the Q factor of fiber dispersion on the converted NRZ signals. Simulation results show that related higher Q factor can be obtained by carefully selecting the duty cycle of the input RZ signal and decreasing the dispersion difference between the RZ signal and continuous probe light.