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1、RFIDTechnologyOverviewProjectMembers:JoeTadduniandAarashHaghighatI.ObjectiveofRFIDThemaingoalofanRFIDsystemistocarrydataonatransponder(tag)thatcanberetrievedwithatransceiverthroughawirelessconnection.Theabilitytoaccessinformationthroughanon-line-of-sightstorag
2、einatagcanbeutilizedfortheidentificationofgoods,locations,animals,andevenpeople.Discerningspecificinformationfromthesetagswillhaveprofoundimpactsonhowindividualsincommerceandindustrykeeptrackoftheirgoodsandeachother.II.BasicsofRFIDRFIDisanacronymforRadioFreque
3、ncyIdentification.ThethreebasiccomponentsofatypicalRFIDsystemareanantennaorcoil,atransceiver(readerwithdecoder),andatransponder(tag)withelectronicallyprogrammedinformation.InanRFIDsystem,anantennacontinuouslyemitsradiosignalsatagivenfrequency.Whenatransponder(
4、thatissettodetectthatspecificfrequency)comesintocontactwiththesesignals,thebadgeisactivatedandcommunicateswirelesslywiththereaderthroughthemodulationoftransmittancefrequencies.Throughtheuseofanantenna,theinformationthatisstoredonthetranspondercanbereadorwritte
5、nfromthetransponder.Typically,theantennaispackagedwiththetransceiverintoalargerstructurecalledareader(interrogator)thatisinchargeofthesystem’sdatacommunicationandacquisition.Thedatathatisobtainedandanalyzedbythereadercanthenbetransportedtoacomputerthroughseria
6、l,parallel,orbuscables.ThegeneraldesignofasimpleRFIDsystemisdisplayedthroughthefollowingfigure:Figure1:BlockdiagramdescribingoperationoftheRFIDsystem.4III.DistinguishingFeaturesofRFIDPassive/Active:RFIDtagscanbecharacterizedaseitheractiveorpassive.Traditionalp
7、assivetagsaretypicallyin“sleep”stateuntilawakenedbythereader’semittedfield.Inpassivetags,thereader’sfieldactstochargethecapacitorthatpowersthebadge.Duetothestrengthofthesignalthatisrequired,passivetagsaremostoftenusedforshortread-rangeapplications(severalinche
8、s)andrequireahigh-poweredreader.Passivetagsareoftenverylight,compact,andhaveunlimitedlifespans.However,drawbacksofthistechnologyincludelimitedmemorystorage(rangingfrom32-128bits)an
