Inthelastfewyears,inthemobilecommunicationmodulatesthedemodulationtechnologysuperiorityinthedevelopmentspeedandthenewapplicationnumberaspect,forhumanextremelyprofoundimpression.Alongwiththesocialeconomydevelopment,themodulatingtechnologymodulatingtechniquerenewscontinuouslyagainandisconsummating,atthesametime,themobilecommunicationhaspassedthroughthefirstgenerationofmobilecommunication,thesecondgenerationofmobilecommunicationandsoonentersthethirdgenerationmobile、communication.Betweenthis,themodulatingtechnologymodulatingtechniquedevelopmentisplayingtheextremelyvitalroleininside.Inrecentyears,ourmobilecommunicationserviceswiftandviolentdevelopment,penetratedintosociallifeeachaspect,facingthemotionusergroupcontinuallygrowthandnewserviceemergingoneafteranotherincessantly,themobilecommunicationsystemmustadaptpromptlyeveninadvanceinthemarketdemandstep.Buttookofadigitalmodulatingtechnologymodulatingtechniquemobilecommunicationcoretechnologiesistherealizationhighspeed,thehighlyeffectivemobilecommunicationsystemimportantguarantee.Thedigitalmodulationdemodulationtechnologyholdstheextremelyimportantstatusinthedigitalcommunication,thecommonlyuseddigitalmodulationincludes:Frequencyshiftkeying(FSK)andphase-shiftkeying(PSK)andsoon.Atpresenthasusedinthemobilecommunicationsystemthemodulatingtechnologymodulatingtechniquebeingpossibletodivideintotwobigkinds:Thelinearmodulationtechnologyandthepermanentenvelopingmodulatingtechnologymodulatingtechniquelinearmodulationtechnologymainlyhas:PSK-BPSK、QPSKOQPSK/4–QPSK、QAM、16QAM、64QAM、256QAM.thepermanentenvelopemodulatingtechnologymodulatingtechniquemainlyhas:MSKTFMGMSK.Thearticleinviewofthethreekindofbasicialmodulationdemodulationtechnologyhascarriedonthedetailedsimulationandtheanalysis,obviously,choosesonekindofmodulatingtechnologymodulatingtechniqueisdeterminedaccordingtothechannelcharacteristicandtheapplication.ThepowerefficiencyandthefrequencyspectrumefficiencycannotbesatisfactorytobothsidesgenerallyunevenAmerica.Thehighfrequencyspectrumefficiencyneedstosacrificecertainpowerefficiencytoobtain;Similarly,thehighpowerefficiencyalsoneedstosacrificecertainfrequencyspectrumefficiency.Alongwiththemodulationtechniqueintheunceasingdevelopment,thenewmodulatingtechnologymodulatingtechniquemightbringthebetterfrequencyspectrumefficiencyandthehigherpowerefficiency.FSKandPSKinthenumeralmobilecommunicationthefindapplication,inwhichFSKalreadyobtainedtheuseinthesimulationmobilecommunicationdigitalsignaling.QAMappliesinthefixedpoint-to-pointdigitalmicrowavesystemwidely,ithastheveryhighfrequencyspectrumusefactor.ButthemobilecommunicationenvironmentregardingthetraditionalQAMmodulationistheseriouschallenge,butinteachesinthecharactermobilecommunicationsystemalsotohaveusesQAM.ExudesEurope'snumeralmobilecommunicationtouseistheGMSKmodulation,butAmericanandJapan'snumeralmobilecommunicationusestheQPSKmodulatingtechnologymodulatingtechnique.Thedigitalmodulatingtechnologymodulatingtechniquediscussedwhichin1986agointernationalconferencenearlyallconcentratedintheabovepermanentenvelopingmodulatingtechnologymodulatingtechnique,theGMSKmodulationreceiveduniversalwelcomeinparticular.Inrecentyearsasaresultoftheamplifierdesigntechnologyprogress,realizedthemodulationmethodpossiblytobecome.In1987theintermediatestage,linearmodulationtechnologiesandsoonQPSKonlythenstartedtobepo...
