中文摘要：

从激光光学、光纤光学的基本结论出发，推导了分布布拉格反射式（DBR）掺铒光纤激光器单纵模工作时腔长应满足的条件，修正了经典理论中的平均损耗因子，得到DBR掺铒光纤激光器的单纵模工作条件；通过仿真，计算出光栅反射率为94％，反射带宽为0．2nm，掺铒光纤增益系数为3dB／m时的单纵模工作区，仿真结果与文献报道中的实验结论相吻合。

英文摘要：

Based on the fundamental conclusions of laser and fiber optics, the single mode working regime of Distributed Bragg Reflector （DBR） optical fiber laser was derived, which is an amendment of classical theory. The single mode working formulation was summarized. Given that the FBG reflectivity is 94% and the reflection bandwidth is 0. 2 nm, and that the gain coefficient is 3 dB/m. The simulation result is consistent with that of the experiment reported in the reference paper.