铋基掺铒光纤放大器中放大自发辐射处理研究

分别设计了一个带光隔离器和一个带光环形器的复合型宽带铋基掺铒光纤放大器(Bi-EDFA),理论上研究了Bi-EDFA中对于后向传输放大自发辐射(ASE)的处理对放大器性能的影响。研究表明,在C+L波段多波长信号同时输入情形下,通过在铋基掺铒光纤中插入一个光隔离器抑制后向传输的ASE,可以提高放大器各波长信号增益,降低噪声系数。利用一个光环形器引导后向传输的ASE去泵浦一段未抽运的低掺杂铋基掺铒光纤,可以显著地提高放大器长波段信号增益,而噪声系数只是略有增加,理论研究与报道的实验结果达到了比较好的一致。研究结果对于新型宽带Bi-EDFA的设计和应用具有一定实际指导意义。

The processing of backward amplified spontaneous emission in a bismuth-based erbium-doped fiber amplifier

A hybrid structure of broadband bismuth-based erbium-doped fiber amplifier(Bi-EDFA) with an optical isolator and an optical circulator is designed,respectively.The effects on performance of Bi-EDFA are presented theoretically when its backward amplified spontaneous emission(ASE) is processed.Under the conditions of the multi-wavelength signal of C+L band is inputted simultaneously,the each signal gain can be improved and noise figure of Bi-EDFA can be decreased by means of suppressing the backward ASE with an optical isolator inserted in the bismuth-based erbium-doped fiber(Bi-EDF).The long-wavelength band signal gain can be enhanced evidently with only a little increasing of noise figure as an optical circulator is utilized to direct the unwanted backward ASE of BiEDFA to pump an un-pumped Bi-EDF.The theoretical simulation is in a good agreement with the reported experimental result.The above results will provide practical significance for a new design and application of Bi-EDFA.