【作者】 王卓；

【导师】 罗志祥； 罗风光；

【作者基本信息】 华中科技大学 ， 物理电子学， 2006， 硕士

【摘要】 对高速Internet的接入和电信网络应用的需求,极大地促进了接入网络的发展。无源光网络(PON)技术适合宽带接入的需要,其最新技术——GPON被业内人士公认为是解决宽带接入网的最佳方案之一,目前正受到越来越多的重视。本文简叙了光接入网的定义、参考配置、拓扑结构,介绍了对媒体接入控制(MAC)的要求,比较了PON的三种主流技术——APON、EPON和GPON的优缺点,详细分析了ONU端的体系结构图。本文的主要工作是负责GPON上行传输的调度分配算法设计和ONU端的TC适配子层的研究。在传统动态带宽分配算法的基础上,本文提出了基于不同优先级业务的改进型带宽分配算法和根据不同业务类型的优先级和等待时间调度的上行成帧算法,并对这两种算法都分析了其有效性,进行了仿真。同时本文还详细介绍了所选择的物理层芯片,分析了TC适配子层中各模块的功能、设计与实现方法以及关键模块的验证,给出了整体联调的时序仿真结果。从波形仿真结果可以看出,模块的设计可以正确实现ONU的TC适配子层预定的逻辑功能。最后,对本文的工作和所得到的结论进行了总结。更多还原

【Abstract】 The demand for accessing Internet with high speed and supporting telecommunication network applications has greatly accelerated the development of broadband access network. The Passive Optical Network (PON) technology fits the requirement to access broadly. The newly proposed technique --- GPON, has been publicly accepted by the insider as one of the most efficient and optimal method to resolve the broadband access network and now being paid more and more attention.The issue gives a sketch of the definition of Optical Access Network with its reference configuration and topology structure, introduces the requirement of Media Access Control, compares the three main method of PON– APON, EPON and GPON with their advantage and disadvantage, analyzes the design of ONU system structure in details. This issue mainly focused on the research of GPON upstream transport schedule & distribution algorithm and design for TC adapting sub-layer of the ONU.Based on the traditional Dynamic Bandwidth Assignment algorithm, the issue proposes an improved algorithm determined by different priorities’services and a new schedule method according to the priority and waiting time, then presents the analysis of the two algorithms about their validities and emulations, introduces the chip used for physical layer in details, discourses each module’s function of TC adapting sub-layer with its design and complementation, gives the key module into verification, presents the timing sequence modulation result of the whole structure. From the waveform, we can get the conclusion that the overall modules implement the ONU’s TC adapting sub-layer’s anticipated logic. Finally, creativeness and conclusions are summarized.更多还原