HFC网络论文：数字电视信号的HFC网络传输研究

1、HFC 网络论文：数字电视信号的 HFC 网络传输研究【中文摘要】目前，中国有线电视数字化工程正在各个城市轰轰 烈烈地开展当中。对于中国的广电技术人员来说，将面临从模拟有线 电视的维护工作向维护数字电视的转变。当前中国的有线电视网络结 构形式基本上都是 HFC 光纤同轴混合） ,从模拟电视向数字电视的转 变需要的仅仅是在网络的前端机房增加数字电视信号编码和调制设 备和用户终端增加数字电视信号解调和解码设备（数字电视机顶盒）,然后将 HFC 网络中传输的模拟电视信号变为数字电视信号就可以完 成。但是，由于数字电视信号和模拟电视信号采用了不同的编码和调 制方式,数字电视信号在原来传送模拟电视信号的

2、HFC 网络中会不会发生新的问题，仅仅从理论分析上是无法预测的。因此,结合南京广电 网络公司数字电视整体转换工程开展 4 个月以来的数字电视业务维 护工作,对 HFC 网络状态和数字电视（QAM 信号传输的影响进行了理 论分析和实验探究。在文章中，主要模拟了 HFC 网络系统内部常见问 题引起的数字电视信号故障，分析了典型的 HFC 网络系统受外界干扰 引起的数字电视信号故障，并根据这两类故障的特点讨论了数字电视 信号非中断故障的排查流程。【英文摘要】Nowadays, the digital TV broadcasting service isdeveloping quickly in ma

3、nycities in China. The changing of TV broadcasting from an alog to digital will be a challe nge to most of our televisi onHFC 网络论文：数字电视信号的 HFC 网络传输研究tech ni cia ns. The main structure ofChina s present Community Antenna Television Network is HFC (HybridFiber Coax).What we need to do to complete the

4、changeis add ing coders and modulators in Head-e nd and decoders anddemodulators in Set-Top-Box, the consumers digital television receiver,then change the signals transmitting in HFC network from analog todigital. However, as an analog signal and a digital sig nal are coded andmodulated in differe n

5、t ways, its difficult to predict if there will be new problems when digital signaltravels in the HFC network which is used for transmitting analog one onlyin theory. As the result, synthesizing the servicing work of digitaltelevision in four mon ths since digital televisi on gen eralizati on project

6、bega n in Nanjing, here are some an alyses in theory andexperimentationsin real situationto study whether the statusof HFC n etwork will in flue nce the QAM sig nal traveli ng in it.In this thesis, somecommoidefects in HFCnetwork system likely to in fluence the digital televisi onsig nal were simula

7、ted, andsome typical exter nal in terfere nce which will in flue nce the digital signals was discussed. At the end of this thesis, con sideri ng thecharacteristics of the two ki nd malfu ncti ons which will in flue nce thedigitalsig nals tran smissi on,how toelim in ate them was discussed.【关键词】HFC 网

8、络 数字电视信号 QAM 数字电视业务维护 常 见故障【英文关键词】HFC(Hybrid Fiber Coax) networkdigital televisi on sig nalQAM(Quadrature AmplitudeModulatio n)servic ing work of digital televisi oncom mon defects【备注】索购全文在线加好友自：1.39938848同时提供论文写作一对一指导和论文发表委托服务【目录】数字电视信号的 HFC 网络传输研究 摘要4-5 Abstract 5 第一章 绪论 8-131.1 本文主要研究目的、意义和内容 8-101.1.1 研究目的和意义 8-91.1.2 研究内容9- 101.2 课题背景 10-121.2.1 HFC 网络发展现状10- 11 1.2.2 数字电视的发展历程 11-121.3 本课题的研究手段和章节安排 12-13 第二章 文献综述 13-192.1 关于 HFC 网络的研究发展 13-152.2 关于数字电视信号的研究发展15-19第三章 理论概要 19-413.1 HFC 网络结构 19-243.1.1 HFC 网络结构概述 19-203.1.2 光缆干线网络结构 20-233.1.3 分配电缆网