宽带接入网的多址接入

【作者】 孙飞燕；

【导师】 仇佩亮；

【作者基本信息】 浙江大学 ， 通信与信息系统， 2002， 硕士

【摘要】 随着信息高速公路的飞速发展，基于Internet的应用已经由单一业务类型向数据、语音、图像“三合一”的多媒体信息形式以及综合业务方向发展。目前，主干网已大步迈向宽带化和数字化，相比起来，原来模拟的，窄带用户环路就成了整个通信网络发展的一大障碍，因此宽带接入技术的研究和宽带接入网的实现成了当前通信领域的一大热点。 多址接入协议是接入网主要考虑的问题之一。随着宽带业务的提出，多址接入协议不能仅仅停留在传统的数据通信网的多址接入协议上，而必须考虑综合业务的接入。本文围绕着通信网中的多址接入协议问题，从理论上深入地研究话音和数据综合业务的多址接入方法及其性能。同时，对HFC／CATV这一宽带多用户接入网络上的话音和数据综合业务的多址接入问题做了详细的介绍和仿真。 CDMA由于其灵活机动，容量高，抗干扰能力强，保密性能好等优点，并且是最有发展前途的一种多址通信体制，因此目前引起国内外通信部门的重视，尤其是国防战术通信及移动通信方面的关注。CDMA通信系统的接收机性能对整个系统的性能影响很大，所以本文对CDMA接收机做了一些介绍。 第一章介绍了几种目前流行的宽带接入网技术以及宽带业务，服务质量，多址接入协议和码分多址技术。 第二章简要介绍了通信网中的多址接入协议的概况。并且对其中的一些典型多址接入方法及其性能做了深入的研究。首先介绍和分析了针对数据业务的预约随机接入(RRA)，然后介绍了支持话音和数据综合业务的多址接入方法PRMA。为了结合ALOHA和CDMA的优点，在ALOHA和PRMA的基础上提出了扩展ALOHA(SAMA)和预约码多址接入RCMA．，并对其性能进行了分析。 第三章对CATV网络的上行接入进行了系统的描述。对原有的只提供best effort服务的接入系统进行了QoS扩展。详细介绍了上行业务流资源预约策略，排队等问题。并用网络仿真软件OPNET进行了仿真。 第四章描述了CDMA接收机的具体实现。介绍了各个硬件功能模块和它们的工作原理。更多还原

【Abstract】 With the rapid development of lnformation Highway, the lnternet based aPplications havetIansferred from single services to integraed services, which provide the data, voice, image, andmovie services to the consumers. Nowadays, with the widebandliZation and digitalization of thetrunk netWorks, the traditional narrow band access netWorks became the bottleneck for thedevelopment of the communication netWorks.Multip1e-Access protocol is one of the most impor’tant problems that the access netWorksmust consideL And it is necessary fOr mu1tip1e-access protocols to take integrated services intoconsideration. In this dissertation, multiple access protocols for integr’ation of voice and data inconununication netWorks are investigated. And detai1ed introduction and simulation to integrationof voice and data in HFC/CATV network is made.For its flexibility, capacity secrecy and robustness against ingressive noise, CDMA is one ofthe most promising multiple-access conununication technologics, especially in mobileconununication. The performance of CDMA receiver has great effect on the whole CDMAconununication system. So CDMA receiver is introduced.Chapter 1 introduce the concepts of broadband access netWoTks, integrated services, QoS,multiple-access protocols and CDMA.ChaPter 2 give a brief survey on the multiple-access protocols in the conununicationnetWorks. And make a deeP stUdy on some rePresentative multiple-access protoco1s. Firstly,intToduce and analysis the reservation random access protocol (RRA), which is fit to the dataservices. Then the packet reservation multiple access (PRMA) protocol is introduced, which is fitto the integrated voice/data services. In order to combine the virtUes of reservation AnOHA andCDMA, we bring fOrward the spread ALOHA (SANA) protocol and reservation codemultiple-access (RCMA) protocol and analysis their performance.ChaPter 3 presents the protocol used in the HFC/CATV netWorks. The protocol istransplanted form DOCSIS1.1. QoS is added into the original access system. Resource reservationstrategies, queue and quality of service are discussed in this chaPter And finally we make somesimulation using the netWork simu1ation tools, OPNET.In chapter 4, the implementation of CDMA receiver is presented in detail.更多还原