同向与反向抽运光纤喇曼放大器的阈值比较

为分析同向抽运与反向抽运光纤喇曼放大器的阈值特性,基于已有的耦合微分方程,采用龙格库塔算法和打靶算法,数值模拟同向抽运和反向抽运光纤喇曼放大器中信号光功率沿光纤的演变过程,在此基础上根据实际情况推导出同向与反向抽运光纤喇曼放大器的阈值公式,这些公式比文献中的阈值公式更全面。然后,详细分析各个参数对同向抽运和反向抽运光纤喇曼放大器阈值特性的影响,并且对两种抽运方式的阈值进行比较,结果表明,各参量对同向和反向抽运FRA的阈值影响有相同的地方,也有不同的地方。相同参数时,反向抽运光纤喇曼放大器的阈值都大于同向抽运光纤喇曼放大器的值。结论对于光纤喇曼放大器的优化设计和实验有指导作用,为进一步的研究提供有益的参考。

Comparison of threshold between forward-pumped and backward-pumped fibre Raman amplifier

In order to analyze the threshold characteristics of forward-pumped and backward-pumped fibre Raman amplifier （FRA） , signal power distribution along a fibre with shooting method and Runge-Kutta method of the coupling equations of for- ward-pumped and backward-pumped FRA was provided. Then, the theoretical expressions of forward-pumped and backward-pumped FRA＇ s threshold which are more accurate are obtained with considering the practical factors, and the effects of every parameter on threshold of forward-pumped and backward-pumped FRA have been detailedly investigated. The threshold of two pumping ways are compared. The threshold of backward -pumped FRA is higher with same parameter. The conclusions are helpful to the study of fibre Raman amolifier.