Zhou Xian, Zhong Kangping, Huo Jiahao, Gao Lei, Wang Yiguang, Wang Liang, Yang Yanfu, Yuan Jinhui, Long Keping, Zeng Li, Lau Alan Pak Tao, Lu Chao
Opt Express. 2016 Jul 25;24(15):17359-71. doi: 10.1364/OE.24.017359.
Polarization-division-multiplexed (PDM) four-level pulse amplitude modulation (PAM4) with coherent detection is a promising low cost solution for 80 km inter-datacenter transmissions at 100 Gb/s and beyond. In this paper, three modified adaptive equalization algorithms for the PDM-PAM4 optical coherent systems, i.e. signal-phase aid least-mean-square (SP-LMS) algorithm, training multi-modulus algorithm (TMMA) and cascaded four-modulus algorithm (CMMA-4), are proposed and compared. Based on the proposed algorithms, 112 Gb/s PDM-PAM4 transmission over 80 km standard single mode fiber (SSMF) in C-band for a bit error rate (BER) below 3.8e-3 is successfully demonstrated without optical amplifier, chromatic dispersion (CD) pre-compensation and extra carrier recovery operations.
具有相干检测的偏振分复用（PDM）四电平脉冲幅度调制（PAM4）是一种很有前景的低成本解决方案，适用于100 Gb/s及更高速率的80 km数据中心间传输。本文提出并比较了三种用于PDM-PAM4光相干系统的改进自适应均衡算法，即信号相位辅助最小均方（SP-LMS）算法、训练多模算法（TMMA）和级联四模算法（CMMA-4）。基于所提出的算法，成功演示了在C波段80 km标准单模光纤（SSMF）上112 Gb/s的PDM-PAM4传输，误码率（BER）低于3.8e-3，且无需光放大器、色散（CD）预补偿和额外的载波恢复操作。
