基于FMF的两模式单通道1000 km MDM传输  

Two-mode Single-channel 1000 km MDM Transmission based on FMF

作　　者：王心怡 王晨[1] 王凯辉[1] 丁俊杰[1] 朱博文 沈磊 张磊 王瑞春 闫长鹍 刘博 余建军[1] WANG Xinyi;WANG Chen;WANG Kaihui;DING Junjie;ZHU Bowen;SHEN Lei;ZHANG Lei;WANG Ruichun;YAN Changkun;LIU Bo;YU Jianjun(School of Information Science and Technology,Fudan University,Shanghai 200433,China;Yangtze Optical Fiber and Cable Joint Stock Limited Company,Wuhan 430073,China;Nanjing University of Information Science and Technology,Nanjing 210044,China)

机构地区：[1]复旦大学通信与信息工程学院,上海200433 [2]长飞光纤光缆股份有限公司,武汉430073 [3]南京信息工程大学,南京210044

出　　处：《光通信研究》2024年第4期1-6,共6页Study on Optical Communications

基　　金：国家科技部重点研发资助项目(2018YFB1800905);国家自然科学基金资助项目(61935005,61720106015,61835002,62127802)。

摘　　要：【目的】随着第五代移动通信技术(5G)、物联网和云计算等信息化带宽消耗型业务的不断涌现,人们对信息高速传输的需求急剧增长。然而由于固有的非线性效应,单模光纤的传输容量已逼近香农极限,其将不再能满足人们对于超高速大容量传输的需求。解决传输容量问题成为当务之急。为了解决大容量通信系统的需求与长距离高速传输等问题,文章搭建了两模式单通道的C波段少模光纤(FMF)传输系统。【方法】在发送端,使用任意波形发生器将数字信号转换为电信号,驱动正交(IQ)调制器对光载波进行调制。调制的信号同时使用模分复用(MDM)和偏振复用(PDM)两种复用技术进行传输。为了实现1000 km的双模信号长距离传输,文章构建了一个双循环回路系统,信号每通过一次环路都将通过一段50 km长的FMF。在传输到目标距离后,由耦合器输出到解复用模块,相干光接收机对解复用的调制信号进行零差检测。最后,存储到示波器进行离线数字信号处理(DSP)。依次对信号进行频域色散补偿、下采样、时钟恢复和最小均方算法,恢复出原始信号。【结果】文章发现,在实验中各信道光信噪比(OSNR)所处的区间内,低信噪比(SNR)情况下误码率(BER)接近理论信道结果,高SNR情况下BER为1×10^(-2)时与理论值相差2.5 dB。文章分别测试了背靠背(BTB)和250、500、750以及1000 km下LP 11a和LP 11b两种模式的BER,在所有距离下的BER均低于实验中设定的28%冗余的低密度奇偶校验码(LDPC)的软判决前向纠错(SD-FEC)门限(5.2×10^(-2))。1000 km传输后的BER分别为1.7×10^(-2)和1.8×10^(-2),总净传输速率为400 Gbit/s。【结论】文章演示了32 Gbaud MDM-PDM 16进制正交振幅调制(QAM)的宽带C波段信号在1000 km的两模式单通道FMF系统中的传输。在接收端,利用先进的多输入多输出(MIMO)DSP算法进行信道均衡,得到的两模式BER分别为1.7×10^(-2)�【Objective】With the continuous emergence of information-based bandwidth-consuming services such as 5th Generation Mobile Communication Technology(5G),the Internet of Things,and cloud computing,people’s demand for high-speed information transmission has increased dramatically.However,due to the inherent nonlinear effects,the transmission capacity of single-mode optical fiber has approached the Shannon limit,and it will no longer be able to meet people’s needs for ultra-high-speed and large-capacity transmission.Solving the transmission capacity problem has become a top priority.In order to solve the needs of large-capacity communication systems and long-distance high-speed transmission problems,we have built a two-mode single-channel C-band Few Mode Fiber(FMF)transmission system.【Methods】At the transmitting end,an arbitrary waveform generator is used to convert the digital signal into an electrical signal and drive the In-phase and Quadrature(IQ)modulator to modulate the optical carrier.The modulated signal is transmitted simultaneously using two multiplexing technologies:Mode Division Multiplexing(MDM)and Polarization Division Multiplexing(PDM).In order to achieve long-distance transmission of dual-mode signals of 1000 km,we construct a dual-circulation loop system.Each time the signal passes through the loop,it will pass through a 50 km FMF.After being transmitted to the target distance,the coupler outputs the signal to the demultiplexing module,and the coherent optical receiver performs homodyne detection on the demultiplexed modulated signal.Finally,the transmitted signal is stored in an oscilloscope for offline Digital Signal Processing(DSP).The signal is sequentially subjected to frequency domain dispersion compensation,downsampling,clock recovery,and least mean square algorithm to restore the original signal.【Results】It was found that within the range of Optical Signal-to-Noise Ratio(OSNR)of each channel in the experiment,the Bit Error Rate(BER)under low Signal to Noise Ratio(SNR)is close to

关 键 词：光纤通信 模分复用 偏振复用 少模光纤 

分 类 号：TN92[电子电信—通信与信息系统]