基于SDH/HFC网络的高速数据广播系统及应用研究

【作者】 汪旭；

【导师】 王开云；

【作者基本信息】 中国工程物理研究院北京研究生部 ， 通信与信息系统， 2003， 硕士

【摘要】 我国的有线电视网作为信息产业的基础平台之一，有着庞大的网络体系。如何充分利用现有网络资源和带宽开展高速数据业务，是我们面临的实际问题。 经过多年的研究，开发出了符合DVB标准、采用QAM调制方式的阳光网高速数据广播系统，同时在国内首次实现了基于SDH／HFC网络的高速数据广播系统集成应用。该系统对信息资源按不同用户群的需求进行汇聚；采用大量数据的广播与用户大容量硬盘的存储方式；在用户端采用近交互方式进行浏览，各取所需。 该系统在不改造现有网络的基础上，与目前绝大多数标准的有线电视传输设备兼容，可应用于覆盖全国、各省市、地市以及县区乡镇的有线电视网络。在一个8MHz的电视频道内支持32Mbps的数据传输速率，同时在硬件上通过频道和子频道进行带宽分配、软件上可以实现按节目进行速率调整。该系统为运营商提供实用的用户授权和节目管理功能、灵活的计收费和带宽分配机制以及动态的节目发送策略，为用户提供动态的数据接收策略，具备简洁的第三方接口。 本文对系统中支持不同网络体系间数据格式的转换的数据编码原理进行了描述。设计了该系统频道和节目管理中心以及用户授权管理中心的构架，并对高速数据广播系统在SDH／HFC网络中的集成和应用进行了较为深入的研究。 在论文的第一章，介绍了课题研究背景和数据广播技术及其现状；第二章对与本文相关的基本理论进行了简介；第三章介绍了高速数据广播系统的原理和应用需求；第四章描述了数据编码设计及效率；第五章详细介绍了管理系统的设计与实现；第六章详细阐述了高速数据广播系统在SDH／HFC网络中的集成与应用；最后进行了总结，提出了对该课题的进一步研究的内容。更多还原

【Abstract】 As one of the information industry platforms CATV (Cable TV) has colossal network architecture in China. We face a challenge of how to exploit the existing network resource and network band to implement high-speed data transport.By adopting QAM (Quadrature Amplitude Modulation) modulation, we have researched and implemented a high-speed data broadcasting system compatible with DVB (Digital Video Broadcasting) standard in the past years, and integrated and applicated the system into SDH/HFC (Synchronous Digital Hierarchy/Hybrid Fiber Coax) network for the first time in China. In the system, information resources are collected and organized by variable requirements of users and data is broadcasted through channels and stored in personal computers so that users can select information in near interaction mode on demand.The high-speed data broadcasting system is compatible with almost all existing standard CATV equipments and can be applicated to networks including the national state or the 1ocal without changing the existing network. It supports 32Mbps of data rate in an 8MHz television channel, and provides functions of assigning band via channel and sub-channel, adjusting program transfer rate by software. In the system, a practical user authorization and program managing function, a flexible charge and band assigning mechanism, a dynamic program transfer policy are provided for the service provider of CATV. A dynamic program receiver policy is provided for users of CATV. A simple interface is provided for the third-party application software.In this thesis, principles of data coding for transferring data among different network hierarchies is described, a channel and program management center and a user authorization center are designed, and the integration and application of the system into SDH/HFC network are investigated and implemented.This thesis is divided into seven chapters. Chapter 1 deals with the background of the project and dada broadcast technology and its current status. Chapter 2 is concerned with the basic theory involved in the project. In chapter 3, principles and application requirements of high-speed data broadcasting system are described. Chapter 4 details data coding rule and efficiency. In chapter 3, the design and implementation of the management system is discussed. Chapter 6 expounds integration and application of high-speed data broadcasting system in SDH/HFC network. The conclusions of this thesis and furture research in the project are pointing in the end.更多还原