可见光通信日本庆应义塾大学成果展示

Ｍ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．1VisibleLightCommunicationsMasaoNakagawaKeioUniversityVisibleLightCommunicationConsortium2007October25Ｍ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．21WavesforWirelessCommunicationsLowfrequency(longwavelength)Highfrequency(shortwavelength)RadiowaveInfraredVisibleLightUltravioletＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．32NewLightSourceＬＥＤＬＥＤtaillampTrafficsignalＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．4ＬＥＤspotlightmodulatedbypositiondataＬＥＤspotlightmodulatedbymusicＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．5BlueLDFiberFluorescentmaterialNewwhitelightsourceusingＬＤ（LaserDiode）Ｍ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．6LuminousEfficiency(lm/w)inLED200150100500FluorescentlightDischargelamp1960198020002020YearＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．7NormalizedMagnitudeResponseofWhiteLED(dB)0-5-10-15-202MHz-3dBＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．8BlueLEDFluorescentmaterialWhiteLightSeveraltenmega-HertzSeveralmega-HertzMechanismofwhiteLEDresponseＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．9Twomechanismsforilluminatingwhite(1)WhiteLEDusingfluorescentmaterial(2)Mixedthreecolors(RGB)Ｍ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．10BlueGreenRed450550650nm（wavelength）ThreeColors=WhiteThreecolorLEDhasgoodfrequencyresponseandcanchangeitscolor.However,itneedsthreeLEDelectrodes.Ｍ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．11450550650nm（wavelength）WhiteLEDoffluorescentmaterialdrivenbyblueLEDBlueYellowfluorescentＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．12ThefirstexperimentofVisibleLightCommunicationswasdonebyGrahamBellwhosesystemwascalledPhotophone.Helovedtheidea.ThispictureisfromthewebsiteofBellLaboratorieswhoseexperimentshowed200mdistancevoicecommunication.PhotophonebyGrahamBellin18803.HistoryofVisibleLightCommunicationsＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．13Radiocanbeeavesdroppedbyhostilewarshipsorairplanes.Lightcanbehardlydone.MorsecodedlightSecurity:NoeavesdropPositioning:TofindthepositionofthegroupshipMulti-function:SearchlightandcommunicationbothＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．143kHz３０ｋHz300kHz３MHｚ３０MHｚ３００MHｚ３GHｚλ：10ｃm1cm1mm0.1mm0.01ｍm1μmVLFLFMFHFVHFUHF3GHz３０GHz300GHz３THｚ３０THｚ３００THｚ３PHｚVisiblelightSub-millimeterwaveFarinfra-redNearinfra-redMobilePhone4GMobileTVRadio4.RadioWaveRadiowaveLightwaveＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．15TelephoneWiredCommunicationsMobileWirelessCommunicationsUbiquitousCommunicationsEverywherereceivingandtransmittingTalkingobject,PinpointcommunicationEvery-housereceivingandtransmittingＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．16Mobilecommunicationsusesradiowave,whichpropagateseverywhere.However,itpropagatestoomuchforubiquitouscommunications.Ｍ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．17Fluorescentlightcanalsotransmitinformation.5.FluorescentlightandLEDＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．18LED(LightEmittingDiode)willbecomeaubiquitousdevice.PilotlampTrafficsignalBacklightforliquidcrystalLEDscreenTaillampforcarRoomlightforcarHeadlightforcarCorridorlightinbuildingRoomlightinbuildingFutureLEDasaubiquitousdeviceＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．196.InfrastructureMono-functionalinfrastructureMulti-functionalinfrastructureRoadisatypicalmulti-functionalone.Telephonenetworkisalsomulti-functional.Mostofinfrastructuresaremulti-functional.Lightingisnowamono-functionalinfrastructure.Itwillbecomemulti-functional.Ｍ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．20LEDlightismodulatedbyalocationIDandothers.CellularchannelLocationＩＤ7．VisibleLightCommunicationsforPositioningTostationTostationＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．21ThissystemissupportedbypowerlinecommunicationwhichcanchangetheIDandotherinformation.TostationTostationPowerlineＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．22PCLEDtablelampReceiverPC。Power-linemodemPower-line2002年慶応義塾大学中川研”IntegratedSystemofWhiteLEDVisible-LightCommunicationandPower-LineCommunication”,T.KomineandM.Nakagawa,IEEETrans.onConsumerElectronics,vol.49,no.1,pp.71-79,Feb.2003.VisibleLightCommunications+PowerLineCommunicationsＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．23LEDarraylighting2Dsensorcandetectexactpositioninmm.ExactPositioningＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．24LightingArobotneedsitsexactpositionaswellasahandicappedperson.Ｍ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．25TostationTostationRF-IDtag8.CompetitorsＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．26Comparison-1:VisibleLightIDandRF-IDwithoutbatteryVL-IDＲＦ－ＩＤLongdistanceＲＦ－ＩＤPositionexactness○○×(Thelightisexact)(Beclosetothetag)(Interference)License○○×(Nolicense)(Nolicense)(License)Terminalsize○○×(Small)(Small)(Large)Multi-user○×○(Waityourturn)Easytofind○××Ｍ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．27Comparison-2VisibleLightＩＤandＲＦ－ＩDwithoutbatteryVL-IDＲＦ－ＩＤlongdistanceＲＦ－ＩＤDesign○××Maintenance○××(Touchablefromanypedestrian)Contentchangeable○××(PLC)VisualdefectpersonandHandicappedperson○××（notneedtobeclose)Ｍ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．289.DemonstrationandPracticalUseＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．29Demonstration(1)Findingpositionfromlighting:KeioUniversity,NEC,andMatsushitaDenkoＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．30LEDspotlightmodulatedbyIDdataMobileterminaltestsetＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．31WEBSitePhotodiodewithoutlensＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．32(2)TrafficsignalTheredsignaltransmitstrafficinformation.NipponsignalandNagoyaInstituteTechnologyＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．33(3)KansaiairportexperimentforvisualdefectpeopleconductedbyProf.MakinoofNiigataUniversityMostofvisualdefectpeoplecanfindthedirectionoflight.VLCcantransmitvoicetothem.Ｍ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．34(4)FloorlightingforVLCKeioUniversityＭ．Ｎａｋａｇａｗａ,ＫｅｉｏＵｎｉｖ．35LEDVisibleLightTransmitter:CleardesignPracticaluseatRisuhpeainPanasonicCenterＭ．Ｎａｋ