增益均衡的远程遥泵少模光纤放大器

Gain-Equalized Remotely Pumped Few-Mode Fiber Amplifier

模分复用技术是突破单模光纤通信系统容量极限的潜在途径。在未来可能存在的模分复用与波分复用相结合的系统中,不同空间模式和波长的增益差将制约系统容量和速率。为实现模式增益均衡和波长增益平坦,利用1480 nm LP11模式抽运光抽运44.5 km超低损少模光纤,进行分布式少模光纤拉曼放大。利用残余抽运光抽运少模掺铒光纤,进行集中式少模掺铒光纤放大,实验演示远程遥泵少模光纤放大器。实验表明,在1560~1600 nm增益平坦带宽范围内,LP01和LP11两个模式等效开关增益大于15 dB,模间增益差约为2 dB。

Mode division multiplexing is becoming a potential approach to overcome the capacity crunch of a single-mode fiber transmission system. In the future mode-and wavelength-division multiplexing system, different spatial modes and the wavelength gain difference will affect the transmission capacity and speed. In this study, to realize the modal gain equalization and wavelength gain flatness, a 44.5 km few-mode fiber with ultra-low loss is pumped by the 1480 nm pump light with LP11 mode,and the distributed Raman amplification through the few-mode fiber is realized. The few-mode erbium doped fiber is pumped by the residual pump light, and the lumped few-mode erbium doped fiber amplification is realized. A remotely pumped few-mode fiber amplifier is experimentally demonstrated. The average equivalent on-off gain is greater than 15 dB, and a differential modal gain approximately 2 dB in the wavelength range of 1560-1600 nm is achieved.