葛彦麟 基于GPRS的无线显示系统的设计与实现 外文翻译 第二稿.doc

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1、东南大学成贤学院外文翻译材料电子工程系自动化专业学生姓名：葛彦麟学号：01207111　　设计地点：东南大学成贤学院指导教师：汪力纯TheoreticalStudyoftheGeneralPacketRadioServiceAbstract:Ascommunicationstechnologycontinuestomaturea-ndusers’qualityhavebecomeincreasinglydemanding,newda-taapplicationsareemergingandarereachingthegenera

2、lpublic.ThroughtheuseofGPRS(GeneralPacketRadioService)techn-ology,theexistingGSMnetworkscanbeeasilyachievedwithsimplehigh-speeddatapacketaccess,enablingmobileoperatorstorespondrapidlytomarket段落为1.5行距，标尺幅面44demandsandgaincompetitiveadva-ntage.Thispaperaimstoprovideaco

3、mprehensiveyetsimpleoverviewoftheGPRSsystemfromtheuser’sandfromthearch-itecturalperspectives.Keywords:GPRSnetworks;Voice/dataintegration;Multiple-channels;Packetradio;Telecommunications1IntroductionInthelate1800s,Marconididthepioneerworkestablishingthefirstsuccessful

4、radiolinkbetweenaland-basedstationandatugboat.Sincethen,wirelesscommunicationsystemshavebeendevelopingandevolvingwithafuriouspace.Thenumberofmobilesubscribershasbeengrowingtremendouslyinthepastdecades.Intheearlystages,wirelesscommunicationsystemsweredominatedbymilita

5、ryusageandsupportedaccordingtomilitaryneedsandrequirements.Duringthelasthalfacentury,withincreasingcivilapplicationsofmobileservices,commercialwirelesscommunicationsystemshavebeentakingthelead.Theearlywirelesssystemsconsistedofabasestationwithahigh-powertransmitteran

6、dservedalargegeographicarea.Eachbasestationcouldserveonlyasmallnumberofusersandwascostlyaswell.ThesystemswereisolatedfromeachotherandonlyafewofthecommunicatedwiththePSTNs(PublicSwitchedTelephoneNetworks).Today,thecellularsystemsconsistofaclusterofba-sestationwithlowp

7、owerradiotransmitters.Eachbasestations-ervesasmallcellwithinalargegeographicarea.Thetotalnum-berofusersservedisincreasedbecauseofchannelreuseandal-solargerfrequencybandwidth.GlobalsystemformobilecommunicationsistheEuropeanstandardforcellularcommunicationsdevelopedbyt

8、heETSI(EuropeanTelecommunicationsStandardsInstitute).ThroughoutEuropeandtherestoftheworld,GSMhasbeenwidelyadopted.Ithasalreadybeeni