In dwdm , the nonlinear effects such as self - phase modulation ( spm ) , cross - phase modulation ( xpm ) become important 然而多波長的密集傳輸使得光纖中的非線性效應(自相位調制、交叉相位調制等)顯著增強。
We derive an analytic expression of the group velocity dispersion ( gvd ) induced chirp and the self - phase modulation ( spm ) induced chirp in the normal dispersionregion of non - kerr - like optical fibers with saturable nonlinarity . the evolution of chirp is simulated by numerical methods . the studied results show that the more powerful saturable effects , the smaller is chirp and the gently is chirp . the net chirp is zero in the central region of the pulse 從理論上推導出具有飽和非線性的非克爾光纖正常色散區內,群速度色散效應導致的啁啾和自相位調制效應導致的啁啾解析表達式.利用數值解法模擬了非克爾光纖正常色散區啁啾演變過程.研究結果表明:當非克爾光纖的飽和非線性增強時,凈啁啾不斷減小,而且,越來越平緩,脈沖中心附近區域凈啁啾接近零