自适应多维度的无栅格光传输系统中关键问题研究

The gridless optical transmission system is a hot research field due to its dynamic spectral division and flexible resource allocation, in which the multi-dimensional tuning and self-adaptive scheme are two key points. The dynamic link impairment requires the multi-dimensional collaborative compensation among spectrum, speed, modulation format and FEC. Second, the optical receiver needs a self-adaptive mechanism to match the changing optical signal. Meanwhile, the density of optical carriers and their big frequency offset require new digital signal processing algorithm. Bases on the parameter-controlled signal self-adaptive theory, this application will first study the self-adaptive multi-dimensional gridless optical transmission model; we will analyze the mechanism between the gridless optical signal and transmission channel, and realize the impairment compensation of quasi-time changing optical link as well as optimization of multi-dimensional model; we will propose the transmit/receive method of gridless optical signal based on symbol leading and self-adaptive hierarchical modulation, including the identification of optical leading symbol and the generation of self-adaptive hierarchical modulated optical signal; we will also study the digital compensation and estimation mechanism of time-domain filtering and continuous phase coding, and build the experimental platform of self-adaptive multi-dimensional gridless optical transmission system. The research work has an important theoretical and practical significance for the development of future flexible and reconfigurable optical transmission system.

无栅格光传输系统以其动态的频谱划分和灵活的资源配置，成为未来光通信系统的热点研究领域，多维度调谐与自适应机制是该系统的关键。动态的链路损伤需要频谱结构、传输速率、调制格式与FEC的多维度协同补偿；光接收机需要一套自适应机制实现对无栅格光信号的动态匹配；而密集的载波间隔与可调谐光源的大频偏问题需要新的数字均衡算法。 本申请基于对多变量可控的信号自适应理论，将研究自适应多维度的无栅格光传输模型，综合分析无栅格光传输信号与传输信道的作用机理，实现准时变光链路损伤补偿与多维度优化体系；提出基于符号前导和自适应分级调制的无栅格光信号发射/接收方法，包括研究光前导符号的识别特性与自适应分级调制光信号的产生机理；研究基于时域滤波和连续相位编码的数字均衡算法，搭建自适应多维度的无栅格光传输系统实验平台，为发展未来灵活、可重构的光传输系统确立新的准则，具有重要的理论与实用意义。

无栅格光传输系统能够实现单纤资源的优化匹配，增加光传输的灵活度，是未来光传输网的发展趋势之一。项目组针对无栅格光阐述系统存在的链路损伤、收发协同和密集子载波的串扰等问题，对多维度可调的无栅格光传输模型、自适应分级调制的收发机制和相关的数字信号处理算法展开了研究工作。项目组建立了多维度可调的无栅格光传输系统模型，提出了多种无栅格光信号的收发方案，包括采用多带滤波器组、全光方法产生和自适应编码扩频等多种方法；提出了基于动态删余和自适应截断低复杂度的LDPC纠错编码算法，实现了基于连续相位编码的抗频偏多载波传输方法，提出了基于分级调制的自适应比特映射方法和基于反馈控制的自适应信号均衡算法，建立了自适应无栅格光传输实验系统，并进行了所提方案的实验验证。基于上述研究成果，发表了SCI检索论文11篇，EI检索论文2篇，申请了发明专利6项，培养了研究生5人。项目取得的研究成果将为无栅格灵活光传输网在我国的发展奠定一定理论与实验基础，并推动灵活、可重构的全光网业务在我国的进一步发展。