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1、《通信专业英语》大作业姓名：罗强学号：201230105089序号：01号系别：中兴通信工程学院班级：12级通信六班完成时间：2014、12、26一、翻译4GMobile:4GMobileVoicewasthedriverforsecond-generationmobileandhasbeenaconsiderablesuccess.Today,videoandTVservicesaredrivingforwardthirdgeneration(3G)deployment.Andinthefuture,lowcost,highspeedw
2、illdriveforwardthefourthgeneration(4G)asshort-rangecommunicationemerges.Serviceandaplicationubiquity,withahighdegreepersonalizationandsynchronizationbetweenvarioususerappliances,willbeanotherdriver.Atthesametime,itisprobablethattheradioaccessnetworkwillevolvefromacentrali
3、zedarchitecturetoadistributedone.声音是第二代移动驱动，并得到了相当大的成功。今天，视频和TV服务正在向第三代（3G）发展。并且在以后，低成本和高速的特点将带动它们进入第四代（4G）即短距离通信，随着服务和折叠技术的普及，各种用户设备之间的个性化和同步化程度越高，将成为另一个驱动器。在同一时间，该无线电接入网络有可能将来自集中式架构演进到一个分布式之一。1.ServiceEvolutionTheevolutionfrom3Gto4Gwillbedrivenbyservicesthatofferbetterq
4、uality(e.g.,videoandsound)thankstogreaterbandwidth,moresophisticationintheassociationofalargequantityofinformation,andimprovedpersonalization.Convergencewithothernetwork(enterprise,fixed)serviceswillcomeaboutthroughthehighsessiondatarate.Itwillrequireanalways-onconnection
5、andarevenuemodelbasedonafixedmonthlyfee.Theimpactonnetworkcapacityisexpectedtobesignificant.Machine-to-machinetransmissionwillinvolvetwobasicequipmenttypes:sensor(whichmeasureparameters)andtags(whicharegenerallyread/writeequipment).Itisexpectedthatuserswillrequirehighdata
6、rates,similartothoseonfixednetworks,fordataandstreamingapplications.Mobileterminalusage(laptops,personaldigitalassistants,handhelds)isexpectedtogrowrapidlyastheybecomemoreuserfriendly.Fluidhighqualityvideoandnetworkreactivityareimportantuserrequirements.Keyinfrastructured
7、esignrequirementsinclude:fastresponse,highsessionrate,highcapacity,lowusercharges,rapidreturnoninvestmentforoperators,investmentthatislinewiththegrowthindemand,andsimpleautonomousterminals.Theinfrastructurewillbemuchmoredistributedthanincurrentdeployments,facilitatingthei
8、ntroductionofanewsourceoflocaltraffic:machine-to-machine.1．服务革命从3G到4G演进将由更高质的服务（例如，视频和声音）推动，更大的带
