relesslink,andsoftwareconstraintslikeourlackofcompletesynchronizationalgorithmsinthesoftware,whichcausesustouseawiredsynchronizationchannel.ThespiritofthiscontributionistosummarizeourmethodanddescribeourfirsteffortstowardsthedevelopmentofacompleteMIMO-OFDMplatformdesignedforsystemvalidationandFig..AMIMO-OFDMspatialmultiplexingsystemchannelmeasurements.Moreworkneedstobeinvestigatedtoovercomethelimiforwirelesslocalareanetworks(WLANs).MIMO-OFDMtechnologyisintheprocessofbeingstandardizedbytheIEEETechnicalGroup.n[]andpromises外文文献原文tobeastrongcandidateforfourthgeneration(G)wirelesscommunicationsystems[].AsthetheorybehindMIMO-OFDMcommunicationcontinuestogrow,itbecomesincreasinglyimportanttodevelopprototypeswhichcanevaluatethesetheoriesinrealworldchannelconditions.Duringthepastfewyears,anumberofMIMO-OFDMprototypeshavebeendeveloped[]–[].TheseimplementationsmakeuseofFPGAsorDSPs,whichrequirealargeamountoflowlevelprogrammingandafixedpointimplementation.Thisisthepreferredsolutionwhendevelopinghigh-speedimplementations；however,ithinderstheflexibilityoftheplatformasthesesystemsarenoteasilyreconfigurable.Asaresultwhenexperimentingwithmanydifferentspace-timecodingschemesorreceiverdesigns,amoreflexiblesolutionmaybepreferred.InthispaperweproposeaMIMO-OFDMsystemarchitecturebasedonthesoftwaredefinedradio(SDR)paradigm.Theadvantageofthisapproachliesinthefactthattheuserisnotrequiredtohaveindepthhardwareknowledgeandmayimplementanumberofdifferentschemesbysimplyreconfiguringthesoftware.TheplatformusesNationalInstrumentsradiofrequency(RF)hardwareinconjunctionwiththeLabVIEWgraphicalprogramminglanguage.Withthisarchitecture,itispossibletodefineandsimulateasysteminahighlevelprogramminglanguageandthenseamlesslyapplythatcodetowardsthehardwareimplementation–thisgreatlyreducesthetimeinvolvedinsystemprototyping.Comparedwith[]–[],ourprototypingplatformcaneasilybereduplicatedasitconsistsofcommercial-off-the-shelfhardwareandpubliclyavailablesoftware.AuserwhopurchasestheRFhardwarefromNationalInstrumentsanddownloadstheavailableMIMOsoftwaretoolkitalongwiththeprototypingcodedevelopedbytheauthors(availableat[],[])canrealizethesamerapidprototypingbenefitswhichwediscussinthispaper.Theflexibilityofthecurrentimplementationoftheprototypeislimitedbysomehardwareconstraints,suchasthebandwidthofthePCIbus,whichpreventsfullyreal-timetransmissionoverthewirelesslink,andsoftwareconstraintslikeourlackofcompletesynchronizationalgorithmsinthesoftware,whichcausesustouseawiredsynchronizationchannel.ThespiritofthiscontributionistosummarizeourmethodanddescribeourfirsteffortstowardsthedevelopmentofacompleteMIMO-OFDMplatformdesignedforsystemvalidationandFig..AMIMO-OFDMspatialmultiplexingsystemchannelmeasurements.Moreworkneedstobeinvestigatedtoovercomethelimi.Pratt,―BroadbandMIMO-OFDMWirelessCommunications,‖inProc.oftheIEEE,Feb.,vol.,pp.–.[]T.Sugiyama,S.Kurosaki,Y.Asai,andM.Umehira,―DevelopmentofaNovelSDM-COFDMPrototypeforBroadbandWirelessAccessSystems,‖inWirelessCommunicationsandNetworkingConference,March,vol.,pp.–.[]S.H.Won,Deuk-SuLyu,andH.J.Park,―PhysicalLayerImplementationandEvaluationofMultipleInputMultipleOutput-OrthogonalFrequencyDivisionMultiplexing(MIMO-OFDM)System,‖inProceedingsoftheICCT,April,vol.,pp.–.[]A.vanZelstandT.C.W.Schenk,―ImplementationofaMIMOOFDMbasedWirelessLANSystem,‖IEEETrans.onSignalProcessing,vol.,no.,pp.–,Feb..[]Univ.ofSouthernCaliforniaUltraLab,―IntelUWBandMIMOChannelMeasurementDatabase,‖http://impulse.usc.edu/[]A.GuptaandR.W.HeathJr.,―MIMO-OFDMPrototypingCodeforLabVIEW,‖http://www.ece.utexas.edu/rheath/research/mimo/proto/.[]S.PatilandR.W.HeathJr.,―LabVIEWMIMOToolkit,‖http://www.ece.utexas.edu/rheath/research/mimo/toolkit.php.[]G.Durgin,T.S.Rappaport,andHaoXu,―Measurementsandmodelsforradiopathlossandpenetrationlossinandaroundhomesandtrees外文文献原文at.GHz,‖IEEETransactionsonCommunications,vol.,pp.–,November.[]V.Erceget.al.,―TGnchannelmodels,‖IEEE.-/r,http://www.wirelessworld.com:/,May.[]A.ForenzaandR.W.HeathJr.,―ImpactofAntennaGeometryonMIMOCommunicationinIndoorClusteredChannels,‖toappearonIEEEAPS-IS’,June.[]J.W.WallaceandM.A.Jensen,―Termination-dependentdiversityperformanceofcoupledantennas:Networktheoryanalysis,‖IEEETransactionsonAntennasandPropagation,vol.,pp.–,Jan..[]A.A.M.SalehandR.A.Valenzuela,―Astatisticalmodelforindoormultipathpropagation,‖IEEEJournalonSelectedAreasinCommunications,vM.Nettles,―AJointMIMOOFDMTransceiverandMACDesignforMobileAdHocNetworking,‖inProceedingsoftheInternationalWorkshoponWirelessAdHocNetworks,Oulu,Finland,May-June.[]J.W.Wallace,M.A.Jensen,A.L.Swindlehurst,andB.D.Jeffs,―ExperimentalcharacterizationoftheMIMOwirelesschannel:dataacquisitionandanalysis,‖IEEETransactionsonWirelessCommunications,vol.,pp.–,March.forwirelesslocalareanetworks(WLANs).MIMO-OFDMtechnologyisintheprocessofbeingstandardizedbytheIEEETechnicalGroup.n[]andpromises外文文献原文tobeastrongcandidateforfourthgeneration(G)wirelesscommunicationsystems[].AsthetheorybehindMIMO-OFDMcommunicationcontinuestogrow,itbecomesincreasinglyimportanttodevelopprototypeswhichcanevaluatethesetheoriesinrealworldchannelconditions.Duringthepastfewyears,anumberofMI外文文献原文中文字外文文献原文：RapidMIMO-OFDMSoftwareDefinedRadioSystemPrototypingAmitGupta,AntonioForenza,andRobertW.HeathJr.WirelessNetworkingandCommunicationsGroupDepartmentofElectricalandComputerEngineering,TheUniversityofTexasatAustinUniversityStationC,Austin,TX-USAPhone:+---,Fax:+---{agupta,forenza,rheath}@ece.utexas.eduAbstract—Multipleinput-multipleoutput(MIMO)isanattractivetechnologyforfuturewirelesssystems.MIMOcommunication,enabledbytheuseofmultipletransmitandmultiplereceiveantennas,isknownforitshighspectralefficiencyaswellasitsrobustnessagainstfadingandinterference.CombiningMIMOwithorthogonalfrequencydivisionmultiplexing(OFDM),itispossibletosignificantlyreducereceivercomplexityasOFDMgreatlysimplifiesequalizationatthereceiver.MIMO-OFDMiscurrentlybeingconsideredforanumberofdevelopingwirelessstandards；consequently,thestudyofMIMO-OFDMinrealisticenvironmentsisofgreatimportance.ThispaperdescribesanapproachforprototypingaMIMO-OFDMsystemusingaflexiblesoftwaredefinedradio(SDR)systemarchitectureinconjunctionwithcommerciallyavailablehardware.Anemphasisonsoftwarepermitsafocusonalgorithmandsystemdesignissuesratherthanimplementationandhardwareconfiguration.Thepenaltyofthisflexibility,however,isthattheeaseofusecomesattheexpenseofoverallthroughput.Toillustratethebenefitsoftheproposedarchitecture,applicationstoMIMO-OFDMsystemprototypingandpreliminaryMIMOchannelmeasurementsarepresented.Adetaileddescriptionofthehardwareisprovidedalongwithdownloadablesoftwaretoreproducethesystem.I.INTRODUCTIONMultiple-inputmultiple-output(MIMO)wirelesssystemsusemultipletransmitandmultiplereceiveantennastoincreasecapacityandproviderobustnesstofading[].Toobtainthesebenefitsinbroadbandchannelswithextensivefrequencyselectivity,MIMOcommunicationlinksrequirecomplexspacetimeequalizers.ThecomplexityofMIMOsystemscanbereduced,however,throughorthogonalfrequencydivisionmultiplexing(OFDM).OFDMisanattractivedigitalmodulationtechniquethatpermitsgreatlysimplifiedequalizationatthereceiver.WithOFDM,themodulatedsignaliseffectivelytransmittedinparalleloverNorthogonalfrequencytones.ThisconvertsawidebandfrequencyselectivechannelintoNnarrowbandflatfadingchannels.CurrentlyOFDMisusedinmanywirelessdigitalcommunicationsystems,suchastheIEEE.a/g[],[]standardsforwirelesslocalareanetworks(WLANs).MIMO-OFDMtechnologyisintheprocessofbeingstandardizedbytheIEEETechnicalGroup.n[]andpromises外文文献原文tobeastrongcandidateforfourthgeneration(G)wirelesscommunicationsystems[].AsthetheorybehindMIMO-OFDMcommunicationcontinuestogrow,itbecomesincreasinglyimportanttodevelopprototypeswhichcanevaluatethesetheoriesinrealworldchannelconditions.Duringthepastfewyears,anumberofMIMO-OFDMprototypeshavebeendeveloped[]–[].TheseimplementationsmakeuseofFPGAsorDSPs,whichrequirealargeamountoflowlevelprogrammingandafixedpointimplementation.Thisisthepreferredsolutionwhendevelopinghigh-speedimplementations；however,ithinderstheflexibilityoftheplatformasthesesystemsarenoteasilyreconfigurable.Asaresultwhenexperimentingwithmanydifferentspace-timecodingschemesorreceiverdesigns,amoreflexiblesolutionmaybepreferred.InthispaperweproposeaMIMO-OFDMsystemarchitecturebasedonthesoftwaredefinedradio(SDR)paradigm.Theadvantageofthisapproachliesinthefactthattheuserisnotrequiredtohaveindepthhardwareknowledgeandmayimplementanumberofdifferentschemesbysimplyreconfiguringthesoftware.TheplatformusesNationalInstrumentsradiofrequency(RF)hardwareinconjunctionwiththeLabVIEWgraphicalprogramminglanguage.Withthisarchitecture,itispossibletodefineandsimulateasysteminahighlevelprogramminglanguageandthenseamlesslyapplythatcodetowardsthehardwareimplementation–thisgreatlyreducesthetimeinvolvedinsystemprototyping.Comparedwith[]–[],ourprototypingplatformcaneasilybereduplicatedasitconsistsofcommercial-off-the-shelfhardwareandpubliclyavailablesoftware.AuserwhopurchasestheRFhardwarefromNationalInstrumentsanddownloadsth        外文文献原文24中文4840字外文文献原文：RapidMIMO-OFDMSoftwareDefinedRadioSystemPrototypingAmitGupta,AntonioForenza,andRobertW.HeathJr.WirelessNetworkingandCommunicationsGroupDepartmentofElectricalandComputerEngineering,TheUniversityofTexasatAustin1UniversityStationC0803,Austin,TX78712-0240USAPhone:+1-512-232-2014,Fax:+1-512-471-6512{agupta,forenza,rheath}@ece.utexas.

文档预览结束

找同类相似 下载到手机