简介:Inthisletter,weproposeahybridanalog/digitaldetectionalgorithm,theCorrelatedIn-terferenceCancellation(CIC)algorithm,forImpulseRadioUltra-WideBand(IR-UWB)system.TheCICalgorithmcorrelatesreceivedsignalwithitsdelayedversionsintheanalogdomainandsamplesthecorrelationoutputatthesymbolrate.Thesymbolratesamplesareprocessedinthedigitaldomaintoperforminterferencecancellation.Therefore,CICworksforhighdataratesystemswithheavyIn-terSymbolInterference(ISI).SimulationresultsshowthatCICachievesgoodperformanceintypicalUWBchannels.
简介:分析了全球信息通信网络发展环境下的宽带泛在网络发展走势及UWB的由来、定义、作用与问题,探讨了技术发展与市场前景和我国频率规划等有关进展问题。
简介:Ananti-interferenceorthogonalcodingisintroducedbasedonHadamardcodeandOrthogonalFrequency-DivisionMultiplexing(OFDM),inwhichallsub-channelsofUltra-WideBand(UWB)systemaredividedintoMsub-bandsandthepoweroftheeverytransmittedsymbolspreadsovereachofthesub-bandsratherthanonesub-band.Thecompletemathematicalanalyticalrelationbetweenencodinganddecodingispresentandtherobustnessofthesystemtointerferenceisexamined.Whensomesub-channelsareaffectedbyinterferenceorjamming,thesystemcouldregeneratethesymbolfromothers.SimulationresultsshowthattheAnti-InterferenceUWB-OFDM(AI-OFDM)systemhasevidentadvantagesoverconventionalUWB-OFDMsystemsaswellastheInterferenceSuppressingUWB-OFDM(IS-OFDM)inBitErrorRate(BER)thankstoitsrobustnesstointerference.Inthecaseofbadinterference,theAI-OFDMsystemcouldworkuptosnuffwithoutanyanti-interferencestep,buttheconventionalUWB-OFDMsystemcouldn't.ComparedwiththeIS-OFDMsystem,theAI-OFDMsystemimprovestheperformanceabout5dBinSignal-to-InterferenceRatio(SIR)andtheorderof1~2inBER.
简介:AkindofarchitectureofTime-to-DigitalConverter(TDC)forUltra-WideBand(UWB)applicationispresented.TheproposedTDCisbasedonpulseshrinking,andimplementedinaFieldProgrammableGateArray(FPGA)device.ThepulseshrinkingisrealizedinaloopcontainingtwoProgrammableDelayLines(PDLs)oratwo-channelPDL.Oneline(channel)delaystherisingedgeandtheotherline(channel)delaysthefallingedgeofacirculatingpulse.DelayresolutionofPDLisconvertedintoadigitaloutputcodeunderknownconditionsofpulsewidth.Thisdelayresolutionmeasurementmechanismisdifferentfromtheconventionaltimeintervalmeasurementmechanismbasedonpulseshrinkingofconversionofunknownpulsewidthintoadigitaloutputcode.Thismechanismautomaticallyavoidstheinfluenceofunwantedpulseshrinkingbyanycircuitelementapartfromthelines.TheachievedrelativeerrorsforfourPDLsarewithin0.80%–1.60%.
简介:Anovellow-cost4-elementplanararrayantennadirectlyfedbyacoaxialcableforUltra-WideBand(UWB)applicationispresented.Theproposedantennaconsistsof2×2bowtieelementsandasimple1:4powerdividerfeedingnetwork.Comparedtothebasicbowtieelement,theimpedancebandwidthofthearrayantennahasasignificantimprovementthatthelowcut-offfrequencyisextendedfrom6GHzofthebowtieelementto2GHz.Themeasuredresultsshowthattheproposedantennahasalargebandwidthof2GHzto11GHzforVoltageStandingWaveRatio(VSWR)<2,andexhibitsabidirectionalradiationpatternandamodestgainacrosstheoperatingbandandapeakgainofabout9dBiat11GHz.
简介:Theexperimentalstudyofultra-wideband(UWB)technology,itsgenerationandon-linemeasurementarepresented.AnexperimentalrepetitiveUWBsystemisdesigned,manufactured,andtested.High-pressuresparkgapswitchanditscomponents,aswellasoilsparkgapswitcharestudiedexperimentallyonthesystem.Experimentalresultsindicatethatthesystemoperatesata200ppsrepetitiveratewithastableperformance.100MWpeakpowerUWBpulsesareobtainedonthesystem.Fast-timeresponsecapacitivedividerisdesignedandfabricated,allowingforanaccuratemeasurementofthehighpowerUWBsignal.ThemainissuesrelatedtothedesignoftheswitchandtheUWBsignalonlinemeasurementarediscussed.