基于传统OM2光纤的大容量模分复用传输系统研究  

Research on Large-Capacity Mode Division Multiplexing Transmission System Based on Conventional OM2 Multimode Fiber

作　　者：于新阔 李建平 秦玉文[1,2] 杨海林 彭迪 向梦 许鸥 付松年[1,2] YU Xin-kuo;LI Jian-ping;QIN Yu-wen;YANG Hai-lin;PENG Di;XIANG Meng;XU Ou;FU Song-nian(Institute of Advanced Photonics Technology,School of Information Engineering,Guangdong University of Technology,Guangzhou,Guangdong 510006,China;Key Laboratory of Photonic Technology for Integrated Sensing and Communication,Ministry of Education,Guangzhou,Guangdong 510006,China)

机构地区：[1]广东工业大学信息工程学院先进光子技术研究院,广东广州510006 [2]通感融合光子技术教育部重点实验室,广东广州510006

出　　处：《电子学报》2024年第7期2461-2467,共7页Acta Electronica Sinica

基　　金：国家重点研发计划(No.2018YFB1800901);国家自然科学基金(No.62022029)~。

摘　　要：基于传统多模光纤的模式资源,来构建多维复用超大容量光纤传输系统可以有效提升通信系统传输容量,满足急剧增长的数据业务需求.在本文中,我们联合波分复用、偏振复用和模分复用技术,基于传统OM2光纤实现了40个波长信道(1 535.04~1 566.31 nm)×2个模式信道(LP01和LP11b)的60 G波特偏分复用16阶正交幅度调制(Polarization Division Multiplexing 16-ary Quadrature Amplitude Modulation,PDM-16QAM)信号的短距模分复用相干光传输.整个模分复用链路由一对基于多平面光转换(Multi Plane Light Conversion,MPLC)的模式复用/解复用器和20 m OM2光纤构成.由于高模式隔离度的模式信道特性(<-20 dB),本系统无需相应数字信号处理算法进行模式解复用,而仅需2×2的多输入多输出(Multiple Input Multiple Output,MIMO)算法完成偏振解复用.在实验中,除了对系统关键参数,包括脉冲成型滤波器的滚降因子、削峰比及接收光功率进行了优化外,还引入了Volterra判决反馈均衡方案.该均衡方案不仅能够补偿调制器引入的非线性信号损伤,而且能够缓解前馈均衡方案导致的高频噪声增强问题.最终,实验结果显示所有80个信道的误码率皆低于20%软判决前向误码纠错(Soft Decision Forward Error Correction,SDFEC)阈值2.7×10-2,系统总容量达38.4 Tbit/s,表明基于多模光纤的模式复用相干光传输方案在未来超大容量短距光互联系统中具有应用潜力.Based on the multiple spatial mode channels of conventional multimode optical fiber,the optical fiber transmission system capacity can be effectively improved by adopting multi-dimensional multiplexing technology and then meet the rapidly growing demand for data services.In this paper,we demonstrate the conventional OM2 fiber based largecapacity optical transmission with a combination of wavelength division multiplexing(WDM),polarization division multi⁃plexing(PDM)and mode division multiplexing(MDM)technologies.Each of the total 80 channels with 40 wavelengths(1535.04~1566.31 nm)and 2 mode(LP01 and LP11b)channels is modulated by 60 Gbaud PDM16-ary quadrature ampli⁃tude modulation(PDM-16QAM)signal.The MDM link consists of a pair of mode multiplexer/de-multiplexer based on multi-plane light conversion(MPLC)and 20 m OM2 fiber.Thanks to the high mode isolation degree of two used mode channels(<-20 dB),only 2×2 multiple input multiple output(MIMO)algorithm is applied for polarization de-multiplexing,and no need to do mode de-multiplexing.In this work,to improve the system capacity,the key system parameters have been optimized, including the roll-off factor of pulse shaping filter, clipping ratio and the received optical power (ROP).And the Volterra decision feedback equalization (VDFE) is also adopted not only to compensate for the nonlinear impair⁃ments introduced by the optical modulator, but also alleviate the high frequency noise enhancement caused by feed forwardequalization (FFE). Then, a total capacity up to 38.4 Tbit/s has been realized with the bit error rate (BER) of all 80 channelslowering than the 20% soft decision forward error correction (SD-FEC) threshold of 2.7 ´ 10-2. The experimental results re⁃veal that the MDM coherent optical transmission scheme based on multi-mode fiber has the potential in the future ultralargecapacity short-distance optical interconnection system.

关 键 词：光纤通信 模分复用 波分复用 相干检测 非线性均衡 

分 类 号：TN929.11[电子电信—通信与信息系统]