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本文可免费下载，只需在本平台注册并通过邮箱验证-会员中心-个人设置”页面的“发送认证邮件，即可获得50积分(没有积分的朋友可以收藏或分享本文、订阅此刊，方便以后阅读)更多资料请登：摘要HFC网络宽带综合业务为进入家庭建立了一个可靠的通道，解决了信息高速公路最后一公里的瓶颈。本文首先对宽带接入网的定义、主要技术及其主要优势作了探讨，接下来又对HFC宽带接入网的技术问题进行了分析讨论，包括HFC接入网的定义及其主要技术，重点研究了HFC接入网回传通道的噪声问题，以及为解决噪声问题而采用的集中分配式HFC网络和S-CDMA电缆调制解调器等。最后对宽带接入网建设的一些问题进行了探讨，对HFC和LAN接入以及ADSL技术作了比较，并结合我国的接入网状况，提出了HFC宽带接入应采用的方案。关键词宽带接入网HFCCablemodemS-CDMAIIAbstractHFCbroadbandintegrationoperationprovidesareliablechanneltofamily,solvesthebottleneckprobleminthelastpartofinformationhighway.FirstthispapermainlymakesthestudytothedefinitionofBroadbandaccessnetwork,andmaintechniqueandthemainadvantages.AndthenitanalysesanddiscussestheconnectiontechnologyofHFCbroadband.TheHFCmainlyincludesthedefinitionanditstechniques.ItemphasizesonthenoiseofHFCbroadbandinbackhaulchannel,andalsostudiestheappliedHFCbroadbandandS-CDMAcablemodelinordertowipeoutthenoise.AfterthediscussionoftheproblemsintheHFCbroadbandconstruction,itcomparestheHFCwiththetechniqueofADSLandconnectionofLAN,andthenfallstogetherwithChinesebandconnectionstatus,HFCbroadbandconnectionshouldbeappliedinthisway.KeywordsBroadbandAccessNetworkHybridFiberCoaxCableModemSynchronousdivisionmultipleaccessIII目录摘要·························································································IAbstract······················································································II第1章绪论···········································································11.1宽带接入网的定义······························································21.2宽带接入网的主要技术························································41.3宽带接入网的优势······························································5第2章HFC宽带接入网技术简述····················································72.1HFC网的组成与基本原理····················································72.2HFC接入网的频段分配·······················································92.3HFC网的拓扑结构···························································102.4HFC网的基本模式···························································122.5基于HFC网的CableModem技术········································132.6HFC宽带接入网技术要解决的问题······································142.7HFC双向传输的实现方式··················································15第3章HFC宽带接入网技术研究···················································173.1HFC业务的扩展······························································173.2HFC网回传通道的噪声问题···············································183.2.1HFC上行通道的噪声特性分析····································183.2.2反向通道的噪声及干扰对数据通信的影响······················193.2.3反向通道噪声的削弱技术···········································193.2.4HFC上行通道多路用户接入的方式······························213.2.5HFC上行通道的噪声与控制·······································223.2.6HFC上行通道的传输特性··········································243.3集中分配式HFC网的抗噪声技术········································243.4S-CDMA技术应用于HFC网络···········································25IV3.4.1回传噪声的“漏斗效应”··············································253.4.2S-CDMA技术的基本原理···········································263.4.3S-CDMA技术应用于HFC网络···································273.4.4基于S-CDMA技术的传输系统在传输速率的优越性·········273.4.5总结······································································28第4章宽带接入网建设若干问题的讨论··········································304.1HFC有线电视CABLE接入与LAN接入的选择······················304.1.1CABLEMODEM接入成本和LAN接入成本对比············304.1.2CABLEMODEM接入和LAN接入管理成本对比············304.1.3CABLEMODEM和LAN市场进入门槛的比较················314.2HFC宽带接入技术与ADSL技术的比较································324.3CABLEMODEM的选择···················································334.3.1DOCSIS1.0调制解调器··············································334.3.2OFDM技术·····························································344.3.3S-CDMA技术··························································34结论·····················································································36致谢·····················································································37参考文献····················································································38附录1外文文献译文··································································40附录2外文文献原文··································································461第1章绪论自美国政府1993年提出建设国家信息基础设施NII，即信息高速以来，讨论和建设信息高速公路的浪潮已推进到欧洲、亚洲、并席卷全世界。韩国和日本是发展最迅猛的国家，这与其政府的大力推动是密不可分的。韩国经过三年的大发展，宽带用户总数突破1000万，宽带普及率达到世界第一，占家庭用户的70％，互联网用户的90％，市场规模达到40亿美元。日本政府也通过各种措施（包括eJapan、uJapan等一系列国家项目）大力推动宽带技术的发展，目前宽带用户总数为1500万，其中光纤到户（FTTh）达到120万，在2005年宽带用户总数已经提高到3000万，其中FTTh达到1000万。一些国家投入大量的人力、物力、财力建设信息高速公路。近两年我国宽带接入网的发展也十分迅速。据初步统计，2003年底我国宽带上网用户达到了1740万，宽带注册用户数为1010万。2001～2003年，我国互联网宽带用户从200万增加到1740万，年均增长率为38.5％，宽带用户增长率是上网用户增长率的5.7倍，我国宽带用户增长进入快速发展期。我国原邮电部已建成了八纵八横的光纤通信主干线，ATM实验网也在多个城市建成，广东省优先建成了带宽多媒体通信网，已在广州，深圳开展VOD业务，并将在广东九城市开通两万用户的VOD网。广电总局也正在全国铺设光缆，实施全国有线电视联网工程，各地有线电视台正积极进行CATV网和HFC技术改造，并已有深圳、广州、青岛等地有线台利用CATV网开展INTERNET接入等多媒体信息服务。[1]所有这些都表明，信息高速公路的建设正在世界各国如火如荼地进行着，同时也可看到，各国在建设信息高速公路中都是以宽带网络的建设为基础的。信息高速公路的建设在技术方面就是要解决如何将图像、高速数据和话音等多种业务综合传送到用户的问题，这其中涉及到的主要是宽带网络技术。宽