Dong Ze, Yu Jianjun, Chen Yifan, Li Fan, Xin Xiangjun
Opt Express. 2022 Apr 25;30(9):14998-15007. doi: 10.1364/OE.452149.
Modern emerging data services and applications have put forward an ever-increasing bandwidth requirement for fiber-optic communication channels. To this end, we propose a novel symbol division multiplexing technology (SDM) by multiplexing/de-multiplexing of multiple quadrature amplitude modulation (QAM) symbols onto one complex constellation point. In our SDM scheme, every 7-bit 128QAM symbol is multiplexed per complex valued signal sequentially according to the optimal many-to-one mapping law, forming a 32QAM in the constellation and achieving an extra 40% gain for symbol capacity in an optical discrete multi-tone transmission system. The experiments prove that the SDM-32QAM successfully mitigates the signal impairments induced by fiber chromatic dispersion and Kerr nonlinearity, thus leading to 3.91-dB superior receiver power sensitivity and 2-dB enhancement of systematic tolerance to fiber nonlinear effect. The results highly motivate a fundamental paradigm in multiplexing techniques for optical fiber communication systems.
现代新兴的数据服务和应用对光纤通信信道提出了日益增长的带宽需求。为此，我们提出了一种新颖的符号分割复用技术（SDM），通过将多个正交幅度调制（QAM）符号复用/解复用到一个复星座点上。在我们的SDM方案中，根据最优的多对一映射法则，每7位128QAM符号依次复用至每个复数值信号上，在星座图中形成一个32QAM，并在光离散多音传输系统中实现符号容量额外40%的增益。实验证明，SDM-32QAM成功减轻了光纤色散和克尔非线性引起的信号损伤，从而使接收机功率灵敏度提高了3.91dB，并使系统对光纤非线性效应的容限提高了2dB。这些结果有力地推动了光纤通信系统复用技术的基本范式。
