基于时域正交波形复用技术的绿色低成本光接入扩容机理研究

The development of broadband access technology at home and abroad is in full swing, and up to five proposals have been submitted to meet the NG-PON2 technical requirements. However, since energy conservation and environmental protection are gaining increasing concerns in recent years, the broadband access network technology which has both low-energy and high cost-effective properties will get tremendous attention. By focusing on three scientific problems which include how to increase the capacity of optical access network at low costs, how to compensate the distorted signal efficiently and how to allocate the bandwidth adaptively, the carrierless amplitude and phase modulation (CAP)-based orthogonal waveform division multiplexing technique (ODMA) will be proposed and comprehensive investigated in this project proposal. Several aspects content are included in this proposal as following: 1) a capacity expansion method of the low-energy, low-cost optical access network will be presented by using ODMA technique; 2) the effect of the interaction of the ODMA signal with fiber dispersion, nonlinearity and beating noise will be analyzed and investigated to present the novel and effective channel estimation and equalization algorithm; 3) an adaptive and dynamic bandwidth allocation algorithm and an intelligent sleep mechanism will be studied and designed; 4) a novel green, low-cost and broadband next generation PON system which combine the ODMA with time division multiple access (TDMA) techniques will be proposed. This project bears its own originalities as following: 1) a novel and low-cost capacity expansion method of optical access network based on ODMA is proposed; 2) the method for the optimal design of multi-dimensional orthogonal CAP filters is presented; 3) a novel, adaptive and dynamic bandwidth allocation algorithm based on the waveform and time slot is designed. Our prophase investigations show that compared with orthogonal frequency division multiplexing (OFDM) technique, the carrierless amplitude and phase modulation (CAP) technique do not need expensive optical and electronic devices, and has simpler algorithm structure, lower energy consumption, and similar broadband performance. Therefore, research results of this project will have great theoretical significance and practical values, and could be used for the implementation of "China Broadband Strategy" program.

国内外宽带接入技术发展如火如荼，符合NG-PON2技术要求的提案多达5项，但随着节能环保设计理念的深入人心，同时具备低能耗和高性价比的接入网扩容技术将越来越受到运营商的推崇。本项目围绕接入网扩容机制、信号损伤均衡机理和自适应调度机制三个科学问题，研究基于无载波幅度相位调制（CAP）的时域波形正交复用技术，主要内容包括：1）基于时域波形正交复用技术的宽带光接入技术；2）支撑宽带光接入的高精度信道均衡和补偿技术；3）高效二维带宽自适应调配及智能休眠节能机制；4）绿色低成本宽带光接入网系统测试与验证。本项目的特色与创新在于：1）时域波形正交复用扩容；2）可重构多维正交滤波器设计方法；3）二维动态带宽分配算法。与正交频分复用技术相比，无载波相位调制算法简单、无需昂贵的高速光电器件和ADC器件、可同时兼顾扩容、成本及能耗。项目研究成果可望用于我国"宽带战略"的实施，具有重大的理论意义和应用价值。

国内外宽带接入技术发展如火如荼，符合NG-PON2技术要求的提案多达5项，但随着节能环保设计理念的深入人心，同时具备低能耗和高性价比的接入网扩容技术将越来越受到运营商的推崇。本项目围绕接入网扩容机制、信号损伤均衡机理和自适应调度机制三个科学问题，研究基于无载波幅度相位调制（CAP）的时域波形正交复用技术，具体完成的研究内容包括：1）研究了多维相互正交 CAP 滤波器的优化设计方法，提出了一种性能优良的新型正交滤波器设计方法（OE Method），能够在保障传输性能的前提下提升频谱利用效率，并进一步打破奈奎斯特带宽极限，提出了一种非正交多维CAP设计方法，极大提升了系统频率利用效率；2）结合时分复用技术搭建绿色低成本宽带接入网系统，提出了一种基于 CAP 滤波器参数和时隙的高灵活性多维度动态资源分配的ODMA-TDMA-PON设计方法，极大优化了PON系统资源分配机制；3）提出了支撑高速多址光接入的信道估计和补偿算法，并将CAP与OFDM结合以进一步提升系统传输性能；4）研究了光纤色散、非线性效应及拍频噪声对信号传输性能的影响规律，据此提出基于发送端载波抑制调制和接收端相干接收的PON系统结构，并结合增强型的DSP算法提高系统容量，实现接入速率80Gbps，覆盖距离20~60km，用户数量 64~512（在接入用户数量为80时用户带宽可达1Gbps）。基于上述研究成果，发表了SCI论文19篇、国际会议论文3篇，并申请了国家发明专利3项，圆满完成了所有研究内容，达到了预期的研究目标。