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1、一、英文原文ModernmobilecommunicationtechnologyInnowhighlytheinformationsociety,theinformationandthecorrespondencehavebecomethemodernsociety“thelife”.Theinformationexchangemainlyreliesonthecomputercorrespondence,butcorrespondstakesthetransmissionmethod,withthesensingtechnology,thec
2、omputertechnologyfusesmutually,hasbecomeinthe21stcenturytheinternationalsocietyandtheworldeconomicdevelopmentpowerfulengine.Inordertoofadaptthetimerequest,thenewgenerationofmobilecommunicationtechnologyseasonableandlives,thenewgenerationofmobilecommunicationtechnologyisthepeo
3、plesaidthatthirdgeneration'scorecharacteristicisthewidebandaddressingturnsonnon-gaproamingbetweentherigidnetworkandnumerousdifferentcommunicationssystem's,gainsthemultimediacommunicationservices.Alongwiththetimeprogress,thetechnicalinnovation,people'sliferequest'senhancement,
4、themobilecommunicationtechnologyrenewalspeedisquiteastonishing,almosteveryothertenyearmobilecommunicationtechnologyhasatransformationupdate,fromthe1980s“themobilephone”topresent's3Ghandset,duringhashadtwomobilecommunicationtechnologytransformation,transitsfrom1GAMPSto2GGSM,fr
5、omGSMtoIMT-2000(i.e.3Gtechnology).Knowsmodernonmethemobilecommunicationtechnologytohavethefollowingseveralaspectimportanttechnology:1.widebandmodulationandmultipleaccesstechniqueThewirelesshighspeeddatatransmissioncannotonlydependonthefrequencyspectrumconstantlytheexpansion,s
6、houldbehigherthanthepresentnumbermagnitudeatleastinthefrequencyspectrumefficiency,mayusethreetechnologiesinthephysicallevel,namelyOFDM,UWBandfreetimemodulationcode.OFDMwithotherencodingmethod'sunion,nimblyOFDMandTDMA,FDMA,CDMA,SDMAcombinesthemultipleaccesstechnique.Inthe1960s
7、theOFDMmulti-channeldatatransmissionhassucceededusesincomplexandtheKathrynhighfrequencymilitarychannels.OFDMhasusedin1.6Mbit/shighbitratedigitalsubscriberline(HDSL),6Mbit/sasymmetricaldigitalsubscriberline(ADSL),100Mbit/sreallyhighspeedfiguresubscriber'sline(VDSL),digitalaudi
8、ofrequencybroadcastanddigitalvideobroadcastandsoon.OFDMapplieson5GHz
