大容量光传输系统发展现状

Development status of large-capacity optical transmission systems

综述了大容量光传输系统的发展现状及最新技术研究进展。理论和实验研究表明,由于光纤的非线性及放大器的带宽等限制,通信容量已经接近了单模光纤的传输极限。因此,光纤通信的发展需要克服单载波传输中高速电器件的限制瓶颈。本文总结了多载波技术的产生方案:用频分复用(OFDM)或奈奎斯特波分复用(Nyquist-WDM)技术提高频谱的利用率,增加信道容量实现P bit/s甚至更高传输速率。另一方面需要从研究光纤本身的角度出发,在考虑成本效益和能源效率的前提下充分利用光纤的空间维度。空分复用技术(多模、多芯)及角动量复用技术(OAM)将成为未来超越单模光纤的容量极限、大幅度提高光纤传输容量的研究重点。

This paper reviews the development and latest research progress of large-capacity optical transmission systems. Theoretical and experimental studies have shown that due to the limitations of the fiber nonlinear effect and the amplifier bandwidth, communication capacity is close to the limit of single-mode fiber transmission. Therefore, on the one hand, the development of optical fiber communication needs to overcome the bottleneck of high-speed electrical devices in single carrier transmission. So this paper investigates the multi-carrier generation schemes like orthogonal frequency division multiplexing （OFDM） technology or Nyquist wavelength division multiplexing （Nyquist-WDM） technology, which can improve spectrum efficiencyand increase channel capacity to achieve Pbit/s rate or even higher. On the other hand, we study from the perspective of the optical fiber itself how to take full advantage of the spatial dimension of the fiber in consideration of cost-effectiveness and energy efficiency. It is shown that space division multiplexing （multi-mode, multi-core） and angular momentum multiplexing （OAM） will be the focus of future research to overcome the limit of the capacity of single-mode fiber and greatly improve optical transmission capacity.