面向下一代并行光互连的多维度无载波幅度相位（CAP）调制技术研究

Due to the advantages including high speed, low power consumption, high density and so on, optical interconnect has recently been acknowledged as the key technology for data centers, high performance computers and high speed electronics to improve the data communication bandwidth, reduce the power consumption, enlarge the distance and reduce the cost. Therefore, it is of great significance to study the next generation optical interconnect technology to continuously support the internet and IT industry of China. The current research focuses on the advanced modulation formats to improve the data rates over a single optical channel. Among those modulation methods, carrierless amplitude phase (CAP) modulation is considered as a potential method very suitable for parallel optical interconnect. Academics and industries are both working on using CAP for short reach applications, and yet facing a lot of challenges. . In this project, we will look into the multi-dimensional CAP modulation for parallel optical interconnect. We will study the method of using two-level four-dimensional CAP (4D-CAP) to realize four-lane parallel optical interconnect which is for QSFP MSA optical transceiver application. We will also study the method of realizing multi-level multi-dimensional CAP for advanced optical interconnect. The outputs of this project can help to overcome the difficulties of using CAP modulation for optical interconnect applications and thus develop next generation optical interconnect products.

光互连技术具有高速、低功耗、大密度等传统电互连远远不及的先进性能，推动了数据中心、高性能计算和宽带电子通信的技术进步和产业升级。积极开展面向下一代光互连的前沿技术研究具有重要战略意义和市场价值。采用先进调制格式来提高单光路传输容量是下一代光互连的重要发展目标，其中多维度无载波幅度相位调制（CAP）技术是极其适合多路并行光互连的调制方法，近年来受到学术和工业界的热烈关注，具有重要研究意义。. 本课题研究面向四路并行QSFP封装的二电平4D-CAP光互连技术，以及多电平高阶调制多维度CAP光互连技术。通过本课题的研究，可以掌握多维度CAP调制实现高速并行光互连的关键方法，解决制约多维度CAP调制光互连技术实用化的关键技术和科学问题，从而得到具有创新知识产权和先进性能的高速多路并行光互连技术方案，为我国的光互连行业发展提供先进的技术储备，为我国下一代光互连产品的开发打下良好的基础。

本项目研究基于多维度 CAP 调制在内的新型高阶调制技术及其光互连应用，目标是实现100G速率的并行光互连。经过4年的项目研究，我们基本完成了项目的既定目标，实现了多个100Gbps的里程碑速率高速互连，得到了包括3D-CAP、4D-CAP、MultiCAP、CDMA-CAP等在内的新型CAP调制方案，并且在相应基础上拓展了多个新型的多维度高阶调制研究，探索了智能化的信号处理方法在CAP等高阶调制码型上的应用，解决了包括VCSEL等多模和单模光互连系统的调制非线性损伤等问题，相关成果具有实际应用价值。本项目得到了远超目标的技术指标，包括单波112Gbps的多模百米VCSEL光互连、单波122G的MultiCAP光互连，主要原因是我们积极跟进国内外最新研究进展，积极结合本项目的研究思路和方法，取得较好的效果。在本项目支持下，相关研究成果发表论文33篇，其中重要期刊论文21篇，申请专利5项，培养并完成毕业课题的硕士研究生4人、博士研究生2人，未完成毕业课题的硕士研究生3人，博士研究生1人。