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HistoryofCellularPhones.doc

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HistoryofCellularPhones Thebasicconceptofcellularphonesbeganin1947whenresearcherslookedatcrudemobile(car)phonesandrealizedthatbyusingsmallcells(rangeofservicearea)withfrequencyreusecouldincreasethetrafficcapacityofmobilephonessubstantially,however,thetechnologytodoitwasnonexistent. AnythingtodowithbroadcastingandsendingaradioortelevisionmessageoutovertheairwavescomesunderaFederalCommunicationsCommission(FCC)regulationthatacellularphoneisactuallyatypeoftwo-wayradio.In1947,AT&TproposedthattheFCCallocatealargenumberofradiospectrumfrequenciessothatwide-spreadmobilephoneservicecouldbecomefeasibleandAT&Twouldhaveaincentivetoresearchthenewtechnology.WecanpartiallyblametheFCCforthegapbetweentheconceptofcellularphoneserviceandit'savailabilitytothepublic.BecauseoftheFCCdecisiontolimitthecellularphonefrequenciesin1947,onlytwentythreecellularphoneconversationscouldoccursimultaneouslyinthesameservicearea-notamarketincentiveforresearch. TheFCCreconsideredit'spositionin1968,andstated"ifthetechnologytobuildabettermobilephoneserviceworks,wewillincreasethecellularphonefrequenciesallocation,freeingtheairwavesformoremobilephones."AT&T-BellLabsproposedacellularphonesystemtotheFCCofmanysmall,low-poweredbroadcasttowers,eachcoveringa'cell'afewmilesinradius,collectivelycoveringalargerarea.Eachtowerwoulduseonlyafewofthetotalfrequenciesallocatedtothecellularphonesystem,andascarsmovedacrosstheareatheircellularphonecallswouldbepassedfromtowertotower. IndividualInventors&MobilePhonePatentsDr.MartinCooperforMotorola. US03906166 09/16/1975 Radiotelephonesystem MartinCooper,RichardW.Dronsuth,;AlbertJ.Mikulski,CharlesN.LynkJr.,JamesJ.Mikulski,JohnF.Mitchell,RoyA.Richardson,JohnH.SangsterRelatedClassPatents Relatedtocellularphonepatentsandcordlessphones,64patentslisted.By1977,AT&TBellLabsconstructedandoperatedaprototypecellularphonesystem.Ayearlater,publictrialsofthenewcellularphonesystemwerestartedinChicago,ILwithover2000trialcellularphonecustomers.In1979,thefirstcommercialcellularphonesystembegan