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ID:33979738
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时间:2019-03-02
《测绘工程专业毕业论文中英文资料外文翻译文献gps通信系统全球移动通信系统》由会员上传分享,免费在线阅读,更多相关内容在工程资料-天天文库。
1、毕业设计(论文)中英文对照资料外文翻译文献(此文档为word格式,下载后您可任意编辑修改!)要求1、外文翻译是毕业设计(论文)的主要内容之一,必须学生独立完成。2、外文翻译译文内容应与学生的专业或毕业设计(论文)内容相关,不得少于XXXX印刷符号。3•外文翻译译文用A4纸打印,需包含中文翻译和英文原文。4、年月口等的填写,用阿拉伯数字书写,要符合《关于出版物上数字用法的试行规定》,女口“2017年5月26日”。5、所有签名必须手写,不得打印。附件:外文原文GSM(GlobalSystemforMobileCommunication)Thesuccessofmobil
2、esystemsacrosstheworldisasignthatcommunicationismovingtowardsamorepersonalized,convenientsystem.Peoplewhohavetouseamobilephoneonbusinesssoonbegintorealizethattheabilitytophoneanytime,anyplaceinone'spersonalliferapidlybecomesanecessity,notaconvenience・Thespeedandrapiditywithwhichthepers
3、onalcommunicationsrevolutiontakesplaceis,unlikefixedtransmissionsystems,highlydependentontechnologyandcommunicationstandards・Formobilethethreekeyelementstoachievingservicetake-uparethecost,thesizeandtheweightofthephone,andthecostandqualityofthelink.Ifanyofthesearewrong,especiallythefir
4、sttwo,thenmarketgrowthisliabletobeseverelyrestricted.Thefixedtelephoneserviceisglobalandtheinterconnectionvariesfromcoaxialcabletoopticalfiberandsatellite.Thenationalstandardsaredifferent,butwithcommoninterfacesandinterfaceconversion,interconnectioncantakeplace.Formobiletheproblemisfar
5、morecomplex,withtheneedtoroamcreatinganeedforcomplex,networksandsystems.Thusinmobilethequestionofstandardsisfarmorecrucialtosuccessthanfixedsystems.Inaddition,thereisalsothevexedquestionofspectrumallocationinthemobilearea.Mobilesystemsoriginallyoperatedinanaloguemode(andstilldo)inthe45
6、0MHzbandmovinglaterto900MHzwithdigitalGSMandthento1800MHzwithpersonalcommunicationssystems.Thehistorytomobilitycansplitintogenerations.Thefirstgenerationsystemsweretheadvancedmobilephonesystems(AMPS)intheUS,totalaccesscommunicationsystems(TACS)inmostofEuropeandNordicmobiletelephonesyst
7、em(NMTS);whichwereallanaloguesystems・ThesecondgenerationisverymuchdominatedbythestandardfirstsetoutinEuropebythegroupspecialmobile(GSM)committee,whichwasdesignedasaglobalmobilecommunicationsystem・TheGSMsystemisbasedonacellularcommunicationprinciplewhichwasfirstproposedasaconceptinthe
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