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1、广西科技大学GuangxiUniversityofScienceandTechnology毕业设计（论文）外文翻译外文题目GSM移动通信系统综述院(系)计算机学院专业通信工程班级学号200900402022姓名指导教师2013年5月20日广西科技大学原文：OverviewoftheGlobalSystemforMobileCommunicationsHistoryofGSM：Duringtheearly1980s,analogcellulartelephonesystemswereexperiencingr
2、apidgrowthinEurope,particularlyinScandinaviaandtheUnitedKingdom,butalsoinFranceandGermany.Eachcountrydevelopeditsownsystem,whichwasincomepaiblewitheveryoneelse'sinequipmentandoperation（Intermsofequipmentandoperationandothercountriesarenotidentical）.Thiswas
3、anundesirablesitution,becausenotonlywasthemobileequipmentlimitedtooperationwithinnationalboundaries,whichinaunifiedEuropewereincreasinglyunimportant,buttherewasalsoaverylimitedmarketforeachtypeofequipment,soeconomiesofscaleandthesubsequentsavingscouldnotbe
4、realized.TheEuropeansrealizedthisearlyon,andin1982theConferenceofEuropeanPostsandTelegraphs(CEPT)formedastudygroupcalledtheGroupeSpecialMobile(GSM)tostudyanddevelopapan-Europeanpubliclandmobilesystem.Theproposedsystemhadtomeetcertaincriteria:lGoodsubjectiv
5、espeechqualitylLowterminalandservicecostlSupportforinternationalroaminglAbilitytosupporthandheldterminalslSupportforrangeofnewservicesandfacilitieslSpectralefficiencylISDNcompatibilityIn1989,GSMresponsibilitywastransferredtotheEuropeaTelecommunicationStand
6、ardsInstitute(ETSI),andphaseIoftheGSMspecificationswerepublishedin1990.Commercialservicewasstartedinmid-1991,andby1993therewere36GSMnetworksin22countries.AlthoughstandardizedinEurope,GSMisnotonlyaEuropeanstandard.Over200GSMnetworks(includingDCS1800andPCS19
7、00)areoperationalin110countriesaroundtheworld.Inthebeginningof1994,therewere1.3millionsubscribersworldwidewhichhadgrowntomorethan55millionbyOctober1997.WithNorthAmericamakingadelayedentryintotheGSMfieldwithderivativeofGSMcalledPCS1900,GSMsystemsexistonever
8、ycontinent,andtheacronymGSMnowaptlystandsforGlobalSystemfor16广西科技大学Mobilecommunications.ThedevelopersofGSMchoseanunproven(atthetime)digitalsystem,asopposedtothethen-standardanalogcellularsystemslikeAMPSintheU
