CommunicationTechnology通信技术Word文档格式.docx

CommunicationTechnology通信技术Word文档格式.docx

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1.1Introductionoftheproject

Withthedevelopmentsofmodernsociety,communicationtechnologiesarebecomingmoreandmoreessentialtohumanbeings.Duringtheperiodfrom1920to2013,researchersmadeacomprehensiveimprovementinthefieldsofvoicequality,connectingspeed,communicatingsecurityandsoon.Inthisessay,themainbodyissubdividedintothreeaspects.Firstly,somecommunicationtechnologiesappliedinhistoryareshowninthefirstsessionfollowedbyanoverviewofthetechnologiesinmoderntimeswhichcoulddescribetheshiftfrom1Gto3G.Thenthesecondsectionismainlyfocusingonanalyzingtheadvantagesanddisadvantagesofeachcommunicationtechnology.Afterthat,aconclusionandapredictionispresentedtosumupthewholeinformationandtelltheimprovementsinthenearestfuturebriefly.

IntheprocessofworkingonthisprojectIcouldlearnagreatdealofknowledgevaluableforthefuturestudylessons,meanwhile,someinformationofhowtousetheresourcesinthelibraryorontheinternetwillbegained.WhatisthemostessentialisthatmyacademicknowledgeisnotsobroadasIchangedmymajorfromMicroelectronics（Undergraduate）toCommunicationEngineering（Postgraduate）,soIneedtochosethisprojecttoenrichmyknowledgethroughreadingseveralacademic

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journalsandbooks.

1.2Backgroundinformationaboutcommunicationtechnologiesinhistory

Intheancientworld,communicationreferstothetransmissionofmessagesfromoneplacetotheotheranditsaimissendinginformation.Peopleusedtosendmessagesbyhorse,pigeon,semaphore,beaconsorengravingonstonepillars.Thesecanbesubdividedintotwocategories:

opticaldeliveryandnon-opticaldelivery.Opticaldeliverycontainsseveralmethodssuchasfirealarm,beacon,bodylanguage,whilenon-opticaldeliveryreferstotheconveyanceofinformationbyengravingonstonepillarsorsendingletterswhicharetransferredbyhorseandpigeon.（BamberGascoigne,1993）

Thecommunicationtechnologiesintheancientworldwereinefficient,especiallywhenthetraveldistancewasremoteandittakesmonthsorevenyearstosendalettertoothers.However,withthedevelopmentofmoderntechnologies,peoples’requestsonquickcontactresultedintheinvestmentofseveralnewcommunicationtechnologiessuchasTelecommunications.AccordingOxfordDictionaries（2013）andMerriam-WebsterDictionaries（2013）,Telecommunicationsrefertothetransmissionofdata,telephone,radioandsoonfromoneplacetotheotherbyusingtechnological

methods（electricalsignalsandelectromagneticwaves）.Alsothistechnologyhas

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severaluniquecharacteristicssuchasthesignalswillnotbeinfluencedbytime,

distanceandplace,whichimplicatesitcanprovidepeoplewitharapid,accurate,reliablecontactingmode.Duetoitsuniquefeatures,Telecommunicationsaredevelopingrapidlyandbeingwidelyused.

Itmustbepointedoutthatitiscommunicationtechnologiesshortenedthedistancebetweendifferentcountries,increasedtheefficiencyofeconomicandchangedpeople’slivingstylesgreatly.

1.3Anoverviewofcommunicationtechnologiesfrom1Gto3GThedevelopmentofmoderncommunicationcanbesubdividedintosixmainperiodsasfollows.Firstly,intheperiodsfrom1920to1940,communicationtechnologiesexperiencedaninitialdevelopment.Forexample,accordingtoRegisJ.B.（2007）,carphoneradiosystemwasfirstequippedintheStLouispoliceonJunethe17th1946beforeitwaswidelyusedinNorthAmericainthe1980s.Inthenexttwentyyears,thetelephonenetwork,whichwasfirstestablishedbyBillSystemequippedinpublicvehiclesaroundtheworld,whichimplicatedapublicusedmobilecommunicationservicehadappeared.ThenAmericanrealizedautomatictuningandautomaticconnectionfrom1960to1970.AccordingtoW.RaeYoung（1979）,BillLabinventedandrealizedtheAdvancedMobilePhoneSystemthatcanbeseenasthefirstgeneration.ItalsomeansaCellularMobileCommunicationNetworkwasestablished.Onthebasis

ofNetworks&

Communications（2005）,theUKhaddevelopedanothercommunication

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systemcalledTACSwhichwasusedintheUKandIrelandin1983.Afterthat,itcanbeseenfromVijayK.G.（2002）,inaround1982,EuropeputforwardaGlobalSystemforMobileCommunicationsSystem（GSM）,whichhadbeenwidelyusedinmostEuropeancountriesintheworldasitcouldimprovethevoicequalityandincreasethenetworksecurity.Lastly,accordingtoPatilC.S.（2012）,attheendof20thcentury,AsiaandEuropepointedoutanewcommunicationsystemcalledW-CDMA,whileAmericanlaunchedCDMA2000.Thesetwosystemscannotonlytransmitvoice,butalsotransmitdigitalinformation,whichcouldprovidecitizenswithamoreconvenientandeasieraccesstowirelessapplications.

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