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UWBtechnology姓名：学号：Contents•1.WhatistheUWB•2.UWBtechnologytheory•3.UWBmaincharacteristics•4.UWBapplicationfield•5.UWBdevelopmentprospects一、WhatisaUWB•UWB(Ultra-Wideband)technologyisalsocalled“superbroadband”,sayagainImpulseRadiotechnology.Ultrabroadbandandother“narrowband”or“broadband”therearetwomajoraspectsofthedifference：•1、UWBbandwidth,accordingtothefederalcommunicationscommission(FCC)definitionofmorethan1.5GHzsignalbandwidth,orthesignalbandwidthandcenterfrequencythanmorethan25%forUWB;Thesignalbandwidthandcenterfrequencyratioisbetween1%~25%forbroadband,lessthan1%fornarrowband,visibleUWBbandwidthsignificantlygreaterthanatpresentallcommunicationtechnologyofbandwidth.•2、theUWBnocarrieroftransmission.Thetraditionalnarrowbandandbroadbandareusingradiofrequency(RF)carrierforsignals,carrierfrequencyandpowerinacertainrangechange,anduseofthecarriertotransmitinformationstatechanges.Onthecontrary,UWBusingbasebandtransmission.AccordingtotheprovisionsoftheFCC,from3.1GHzto10.6GHzofbetween7.5GHzbandwidthfrequencyforUWBUSESfrequencyrange.SUWBTRANSMITTERDUWBRECEIVERWirelesschannelantennaantennaUWBcommunicationsystemmodel二、UWBtechnologytheoryPulsegeneratorPulsemodulemodulationCommunicationchannelLownoiseamplifierMatchedfilter/RelatedreceiverRelatedreceiverSourcecodingChannelcodingmodulationDigitalfilterDACtransmitterADCDigitalsignalprocessingLownoiseamplifierVariablegainamplifierreceiver•Thelaunchwillbebitsymbolsforpulseshapingthroughdigitalfilter,andthenconvertedintoanalogsignalsemitted;Receivingsignalsinturnthroughthelownoiseamplifier(LAN),variablegainamplifier(VGA)andADCbecomediscretesignalafter,thenavailableDSPtechnologyrealizesignaldetection,estimated,diversity,judgmentdecodeprocessreceiving.•Atpresentthemethodofproduceimpulsesourcesareoftwotypes:(1)thephotoelectricmethod(2)electronicmethod•UWBmodulationtechnique:(1)pulseamplitudemodulation(PAM)(2)pulsepositionmodulation(PPM)•UWBtechnologytotheresearchmainlyaroundthefollowingseveralaspects:(1)controllablenarrowpulsetechnology(2)channeltransmissioncharacteristicsandchannelmodel(3)modulationtechnology(4)multipleaccesstechnology(5)signaldetectiontechnology,etc•1、simplesystemstructureUWBpulsetransmittersdirectlyinsmallmicrostripantennas.BecauseofUWBdon'tneedoncarriersignalmodulationanddemodulation,itdoesnotneedthemixer,filter,RF/IFconverterandthelocaloscillatorsuchcomplexdevice,butalsoeasytoCMOSintegratedcircuit.三、UWBmaincharacteristics•2、thehigh-speeddatatransmissionIntheory,awidthis0ofthepulsehasinfinitebandwidth,therefore,thepulsesignaltolaunchoutandhaveenoughbandwidth,musthaveenoughalongthesteepincrease/decreaseandthewidthofthenarrowenough.•3、lowpowerconsumptionBecausedonotusecarrier,onlyinthelaunchwhenanarrowpulseenergyconsumption,andsavethelaunchofacontinuouscarrierwaveenergyconsumption.ThisfeaturealsomakesUWBthroughnarrowingpulsewidthcanbe,inimprovingthebandwidthwithoutatthesametimeincreasespowerconsumption,thisbrokethepasttransmissiontechnologyofpowerconsumptionandbandwidthproportionaltothelaw.•4、highsafety•BecausethesignalenergygeneralUWBsignalisinverywidefrequencyrange,togeneralcommunicationsystem,UWBsignalisequivalenttowhitenoisesignal,andinmostcases,UWBsignalpowerspectraldensityoflessthannaturalelectronicnoisefromtheelectronicnoisepulsesignaldetectionwillcomeoutisaverydifficultthingtodo.•5、multipathresolutionabilityUWBradiobecausethelaunchofthedurationisaveryshortonecyclepulseandoccupiesemptiescomparedisextremelylow,multipathsignalintimeisseparated.Thereforesuitableforindoorsuchcomplexenvironmentofhigh-speedtransmission.•6、theprecisepositionUWBradiowithstrongpenetrationability,canbeinindoorandundergroundforaccuratepositioning,andGPSpositioningsystemcanonlyworkintheGPSsatellitevisiblerange;AndGPSlocationprovideverydifferent,exceedshortpulselocatorcangivetherelativeposition,itspositioningprecisioncanreachlevelcm.•7、stronganti-jammingperformance(emc),thebiterrorratelowBecauseofUWBpulseisextremelynarrow,verywideband,thebandwidthequivalentto1000TVchannelsor30000FMradiochannel,sounitwithinthepowerdensityofthebandwidthisrelativelylow.TheUnitedStatestoUWBtransmissionpoweroftheFCCastrictlimit,thepowerdensityandevenlowerthanthegeneralnoiselevel(suchaslessthanalaptopcomputerradiation).Therefore,UWBforotherlittleimpactonequipment.othershort-rangewirelesstechnologycomparison四、UWBapplicationfield•UWBapplicationfieldisverywide,therearefourmainfields:(1)intheWPAN(wirelessadomainnets)application(2)inthelowspeedWPAN(wirelessadomainnets)application(3)radardetection(4)thepreciselocationofbusiness六、UWBdevelopmentprospects•Andthecurrentpopularshort-rangewirelesscommunicationtechnology,comparedtoUWBhasgreatdatarateadvantage,thebiggestcanprovideupto1000Mbpstransmissionrateoftheabove.UWBtechnologyinwirelesscommunicationofinnovative,interestsexhascausedtheglobalindustryattention.ThebluetoothwirelesscommunicationswithsuchascomparedtoUWBcanprovidefasterandfurther,morewidetransmissionrate,moreandmoreresearchersintotheUWBfield.insomehigh-endtechnologyinmilitaryneedsandcommercialmarketthepu