基于退火算法的四模掺铒光纤放大器设计  

Design of Four-Mode Erbium-Doped Fiber Amplifier Based on Annealing Algorithm

作　　者：王宝源 延凤平[1] 任国斌[1] 郭浩 高娇 Wang Baoyuan;Yan Fengping;Ren Guobin;Guo Hao;Gao Jiao(School of Electronic and Information Engineering,Beijing Jiaotong University,Beijing 100044,China)

机构地区：[1]北京交通大学电子信息工程学院,北京100044

出　　处：《光学学报》2023年第22期142-149,共8页Acta Optica Sinica

基　　金：国家重点研发计划(2021YFB2800900);国家自然科学基金(61827818)。

摘　　要：基于COMSOL平台,设计一种沟槽辅助下双层阶跃折射率结构的四模掺铒光纤。通过对铒离子能级结构、稳态方程和速率方程的理论研究,利用Matlab软件搭建少模光纤放大器系统。利用模拟退火算法实现三层掺杂区域下的铒离子浓度的优化,以确保所设计的四模掺铒光纤放大器的增益特性。仿真结果表明:在纤芯泵浦方式下利用波长为1480 nm的泵浦光对1550 nm的四模式信号进行放大,得到的各模式信号平均增益为26.07 dB,模间增益差(DMG)为0.106 dB;对所设计光纤进行折射率容差分析,得到的平均增益为26.08 dB,DMG为0.34 dB。结果证明了所设计的少模光纤放大器的稳定特性,其具有广泛的发展前景和应用潜力。Objective With the rapid development of modern communication technology,the transmission capacity of conventional single-mode optical fibers cannot meet growing communication needs,thus leading to the development of various multiplexing technologies.Among them,mode-division multiplexing of few-mode fibers based on space-division multiplexing has attracted much attention because of its simple structure and easy fabrication.The signal-transmission process in the few-mode fiber suffers from power loss,which must be compensated for introducing an amplifier to increase the gain of each mode signal.In addition,amplification involves amplifying the signals of different modes to different degrees,resulting in inter-mode gain differences,which greatly increases the difficulty of subsequent signal processing.Therefore,the few-mode fiber amplifier must reduce the differential modal gain(DMG)while increasing the mode gain to enhance the stability and reliability of the transmission system.Methods A four-mode erbium-doped fiber with a double-layer step-index structure assisted by trenches was designed based on the COMSOL platform.Based on theoretical research on the energy-level structure of erbium ions as well as the steadystate and rate equations,a few-mode fiber amplifier system is built using Matlab software.The simulated-annealing algorithm realizes the optimization of the erbium ions concentration under the three-layer-doped region to ensure the gain characteristics of the designed four-mode erbium-doped fiber amplifier.The gain and gain equalization effect of pump light with wavelengths of 980 nm and 1480 nm on the FM-EDFA were compared,and the 1480-nm pump light with better amplification characteristics was selected for subsequent analysis.The stability of the designed FM-EDFA was analyzed based on four aspects,including the simulation of the noise figure of the FM-EDFA.In addition,the gain characteristics of the FM-EDFA in the C-band are studied based on the varying wavelengths of the signal light.A 1480-nm pump ligh

关 键 词：空分复用 少模光纤放大器 模拟退火算法 增益均衡 

分 类 号：O436[机械工程—光学工程]