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DigitalTelevision.doc

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DigitalTelevision 1989-InternationalTelecommunicationsUnionestablishedthefirstHDTVstandards,basedondigitalpackettransmissionratherthananalogwavetransmission. 1990-TheRCAdogNipperwasjoinedbyasmallercaninecompanionnamedChipper,whorepresentedthesemi-conductor-basedfutureofdigitalconsumerelectronics. 1993-DigitalHDTVGrandAlliancewascreatedtodevelopprototypedigitalhighdefinitiontelevisionequipment.ThomsonintroducedCinemaScreen,thefirstwidescreenTVavailableintheU.S.(butanalog,notyetdigital).ThomsonConsumerElectronicswascreatedbythe1988purchaseofRCAandGEconsumerelectronicsbusinessesfromGeneralElectric. 1994-RCADigitalSatelliteSystem(DSS)becameNorthAmerica'sfirsthigh-powerdirectbroadcastsatellite(DBS)consumertelevisionsystem,withDIRECTV,startedbyHughesElectronicsCorporationin1990intheKu-bandoftheradiospectrum,andthreeHughesHS601satellitesrelaying200channelstoany18-inchdishinNorthAmerica. 1995-Dec.28,EchoStarlauncheditsfirstDirectBroadcastSatellite,EchoStarI,andDISH(DigitalSkyHighway)NetworkcametolifeonMarch4,1996.TheEchoStarCommunicationsCorporationwasfoundedin1980byCharlieErgen,hiswifeCandyErgenandJimDeFranco,tosupplydirect-to-home(DTH)televisionproductsinthelarge-dishC-bandoftheradiospectrum.EchoStarVwaslaunchedbyInternationalLaunchServicesSeptember23,1999,andwillbeginNov.29broadcastinglocalchannelsto13selectedcities. 1996-InDecember,theFCCapprovedHDTVstandardsproposedbytheAdvancedTelevisionStandardsCommittee(ATSC)thatwasformedin1983toreplacetheanalogstandardsoftheNTSC.EachHDTVchannelhasbeenallocatedabandwidthof6MHzforatheoreticaldatarateof19Mbps(butactualratesof14.7to17.9fallshortofthe18Mbpsrequiredforfast-movingsportsbroadcasts,andlessthatthe24Mbpsneededfor1080p).Thisallowedtransmissionofdifferentdigitalsignals,from480to1080interlacedlinesofresolution(butnot1080progressivelines),andfrom640x480dpi(300,000pixels)at4:3normalscreenratioto1920x1080dpi(2millionpixels)at16:9widescreenratio. 1998-Jan.7,DIRECTVandThomsonConsumerElectronicsdemonstratedattheannualInternationalCo