通信系统演进介绍.ppt

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1、数字无线传输宽带无线与多媒体中心王德胜20112021/7/291第1章概论1.1引言☆移动通信已成为当代通信领域内发展潜力最大、市场前景最广的热点技术，☆移动通信用户的增长远远超过了人们的预期，☆未来的无线便携终端数量会超过目前计算机联网的数量，☆其业务也从面向语音通信转变为面向多媒体数据通信2021/7/292展望☆高频谱效率☆高功率效率☆高性价比☆高质量的服务体系：扁平、透明、按需区分服务2021/7/293☆传输方式变化☆交换方式变化☆服务内容变化☆用户容量增大☆覆盖范围与全球漫游☆效率提高1.2从1G到4G的

2、发展2021/7/294Europeanresearchon3Gstartedin1989withintheRACEIprogramand1991inRACEIIEuropeanresearchonsystemsbeyond3Gstartedin1999withintheISTprogram1980s1990s2000s2010s1G+1G2G+2G3G+3GBeyond3G+Beyond3GAnalogWidebandDigital???DigitalEuropeanresearchon3Gcontinuedin19

3、95withintheACTSprogramFrameworkProgram6onfuturesystemsfullcommercialdeploymenttrialsstandardisationresearchEvolutionofmobilecommunicationsystems2021/7/295WirelessdataalreadybeintroducedinsecondgenerationmobileFirstGenerationAnalogueCircuitswitchedBasicvoicetelep

4、honyLowcapacityLimitedlocalandregionalcoverageSecondGenerationDigitalCircuitswitchedVoiceplusbasicdataapplicationsLowdataspeedEnhancementstowardspacketswitchinghigherdataratesTrans-nationalandglobalroamingDigitalPacketandcircuitswitchedAdvanceddata(multimedia)ap

5、plicationsFastdataaccessGlobalcoverageGlobalroamingThirdGenerationBeyondThirdGenerationDigitalPacketswitchedAllIPbased(IPv6)MoreadvancedmultimediaapplicationsUserincontrolFlexibleplatformofcomplementaryaccesssystemsHighspeeddataImprovedQoSGlobalcoverageGlobalroa

6、ming5.1.3Paradigmshiftfrom1stgenerationtowardsbeyond3G2021/7/2962021/7/297一体化网络架构Wi-Fi(WaveLAN)RadioHubCable,xDSL,V9010/100-BaseTWirelessLANBluetoothWirelessPANMultimedia&MessagingServerintegratedvoiceanddatavideopostcardsin-callimageup/downloadcodecconverterban

7、dwidthmanagerstore&forwardplaybackContentMicroBSBTSUMTS/GSMCDMA2000WirelessBackboneandGatewaysLocationServicesIPNetwork2021/7/298Driversof3GBeyond3Gevolution…butdifficulttoextendtohigherdataratewithCDMAonlytechnology;toprovidevariousserviceswithdifferentQoStohav

8、eenoughfrequencyresourcetoaccommodatemoresubscribersDrawbackLowsystemcapacityLowspectrumefficiency02519981999200020015075100125150Tbit/dayRealTime(e.g.Voice)NonRealTi