光纤非线性效应对10 Gb/s波分复用色散补偿系统的限制

Limitation of Fiber Nonlinearities on 10 Gb/s WDM Systems Using Various Dispersion Compensation Schemes

对信道间距为１００ＧＨｚ的８路１０Ｇｂ／ｓ波分复用色散补偿系统进行了计算机仿真，分析了光纤的色散和自相位调制（ＳＰＭ）、互相位调制（ＸＰＭ）、四波混频（ＦＷＭ）等非线性效应在具有级联光放大器系统中的作用。四种色散补偿方案是：ＳＭＦ（常规单模光纤）＋ＤＣＦ１（色散斜率为正的色散补偿光纤）、ＳＭＦ＋ＤＣＦ２（色散斜率为负的色散补偿光纤）、ＴＷ１（色散为正的非零色散光纤）＋ＴＷ２（色散为负的非零色散光纤）和ＴＷ２＋ＴＷ１。结果表明：ＴＷ２＋ＴＷ１方案具有最好的传输性能，此时色散、自相位调制、互相位调制和四波混频具有几乎同等的作用；ＳＭＦ＋ＤＣＦ１方案的传输性能最差。

Wavelength Division Multiplexed (WDM) system characteristics using various dispersion compensation schemes are compared by computer simulation. In our model, eight 10 Gb/s WDM channels with channel spacing of 100 GHz are transmitted through cascaded optical amplifiers. Fiber dispersion, self phase modulation (SPM), cross phase modulation (XPM) and four wave mixing (FWM) effects are considered. Dispersion compensation schemes include: conventional single mode fiber (SMF)+dispersion compensating fiber with positive dispersion slope (DCF1), SMF+dispersion compensating fiber with negative dispersion slope (DCF2), non zero dispersion fiber with positive dispersion (TW1)+non zero dispersion fiber with nagetive dispersion (TW2) and TW2+TW1. It is shown that TW2+TW1 has the best performance, where SPM, XPM and FWM are roughly equal. On the other hand, SMF+DCF1 results in the worst performance, where the combination of dispersion and SPM effect dominates, and the shorter wavelength channels suffer from severe pulse distortion.