使用FPGA进行雷达实时数据处理课件

FPGAProgrammingforRealTimeAnalysisofLidarSystemsDr.SamehAbdelazimAssistantProfessor,TheSchoolofComputerSciencesandEngineering,FairleighDickinsonUniversityD.Santoro,M.Arend,F.Moshary,S.AhmedFPGAProgrammingforRealTimeOUTLINEIntroductionMotivationFPGAProgrammingMethodologyLogicDesignImplementationTestingandVerificationHardwareDevelopmentFPGAProgrammingforCoherentDopplerLidarforWindSensingSignalProcessingAlgorithmsFFTI-QDemodulation(Autocorrelation)ResultsFPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.Abdelazim2OUTLINEIntroductionFPGAPrograINTRODUCTIONRealtimeanalysisofLidarsystemsrequiresprocessingofbackscatteredsignalsinstantaneouslyastheyareacquired.BackscatteredsignalscanbeprocessedusingsoftwaresuchasMATLABoncetheyareobtainedbydataacquisitiondevices.Whathappensiftheprocessingrateisunabletokeepupwiththerateatwhichbackscatteredsignalsarereceived.FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.Abdelazim3INTRODUCTIONRealtimeanalysisToprocessbackscatteredsignalsinrealtime,signalprocessingalgorithmswillbeprogrammedintotheFieldProgrammableGateArray(FPGA),sothatbackscatteredsignalsareprocessedrightafterbeingacquired(Co-Processor).SignalprocessingDataacquisition4FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimFPGAforRealTimeAnalysisSignalprocessingDataacquisitFPGAPROGRAMMINGMETHODOLOGYAsignalprocessingalgorithmisinitiallyimplementedasalogicdesign,whichcanbesimulatedandtestedusingMATLAB/Simulinksoftware.ThelogicdesignisthencompiledusingXilinxsystemgeneratortoolsettoproduceahardwareVLSIimage,whichcanbedownloadedintotheFPGA.FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.Abdelazim5FPGAPROGRAMMINGMETHODOLOGYAAccumulatorcircuitFPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.Abdelazim6AccumulatorcircuitFPGAPrograMatlab/SimulinkdesignFunctionverification7FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimAccumulatorcircuitMatlab/SimulinkdesignFunctionPowerSpectrumCalculationFPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.Abdelazim8Powerspectrumofbackscatteredtimedomainsignalscanbeestimatedusingdigitalcircuits(FFTlogiccircuitblock)andbeimplementedontheFPGA.ThecomplexoutputoftheFFTblockisthenmultipliedbyitscomplexconjugatetoobtainthesquaremodulesofthepowerspectrum.PowerSpectrumCalculationFPGPowerSpectraAccumulationAccumulationdigitalcircuitoftheFFToutput(powerspectrum)asimplementedontheFPGA.InthisdesignaFIFOblockisusedasaRAMandthewholedesignactslikearing,whereapowerspectrumvectorof8kcirclestheringuntilanewvectorarrives,thenthestoredvectorisreadfromtheFIFOandaddedtothenewlyarrivedvector.TheresultisthenstoredintotheFIFOuntilanewvectorarrives,andsoon.Thisaccumulationprocesswillbeperformeduntilthecountercircuit(Accumulatorblock)countsto10kX8192samples,whichmeansarrivalof10klasershots,thennewlyarrivedpowerspectraareignoredandstoredaccumulateddataarestreamedouttoanoutputbufferbeforeitisstreamedtothehostPC.FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.Abdelazim9PowerSpectraAccumulationAccuPowerSpectraAccumulationFPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.Abdelazim10PowerSpectraAccumulationFPGALow-Pass(FIR)filterDigitalCircuit11FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimThefrequencyresponseshowsthattheoutofbandsignals(above50MHz)willbesuppressedbyapproximately80dB.Low-Pass(FIR)filterDigitalLow-Pass(FIR)filterDigitalCircuitAXilinxFIRcompiler5.0circuitblockisbeingusedtoperformthistask.TheFIRfilterisdesignedusingMATLAB/Simulinkwithfrequencyresponseshownininthepreviousslide.12FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimLow-Pass(FIR)filterDigitalFPGAProgrammingforCoherentDopplerLidarforWindSensingLidarsystemsemployingfiberlaseroperateatlowenergyperpulse.Therefore,pulserepetitionfrequency(PRF)isincreasedtoobtainhighsignaltonoiseratio(SNR).HighPRFmakesrealtimeanalysisusingonlyadataacquisitioncardandsoftwaresuchasMATLABnearlyimpossible,becausethetimebetweenpulsesisverysmall.

FieldProgrammableGateArrays(FPGAs)offerasolutionforrealtimeanalysis.FPGAalsohelpstoreducetheamountofdatatransferredfromthedataacquisitioncardtothesystem(usuallyaPC).FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.Abdelazim13FPGAProgrammingforCoherentCoherentDopplerLidarSystemA20KHzPFRanda14-bitADCwithasamplingrateof400MHz(eachpulseis50µsandcontains20,000samples),datatransferratefromthedataacquisitioncardtothehostPCwillbe800Mbyte/sec.Thehighdatatransferrateisdifficulttobeachievedandrequiresadditionalhardwareandsoftware.Moreover,theamountofdatacollectedin1daywillbemorethan69Tbyte,whichmakesdataarchivingforjustafewdaysnearlyimpossible.DuetothefastPFR,signalprocessingonthehostcomputercannotbeachievedinrealtime,andwillcausedatatobelost.14FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimCoherentDopplerLidarSystemAFFTPre-processingAlgorithmFPGAlogiccircuitsrunat250MHzclock,therefore,twosamplesarestackedtogethertoforma32-bitwordinordertoachievea400Msamples/secflowrate.A32-bitwordhastobebrokenintoitsoriginaltwo16-bitsamplestoallowfordataanalysis.Thisisaccomplishedbyusinga32-bitto16-bitconvertercircuit.Downconvertingdatasamplesfrom32-bitto16-bitwilllowerthedataflowrate,andasaresult,willleadtosamplesoverflowandeventuallydataloss.Toovercomethisproblem,aframesizeofonly8192samplesisacquiredateveryrisingedgeofanexternaltriggersignalthatissynchronizedwiththesignaldrivingthelaserpulses.Asaresult,only8ksamplescanbeacquiredbytheADCateachpulse.Thisallowsfordatadown-conversionwithoutanydataloss,however,itlimitstherangedistancetoapproximately3.1km.15FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimFFTPre-processingAlgorithmFPNowthatthelogicwasimplementedandtestedforproberoperation,itwillbeembeddedwiththelargerdataacquisitionlogicdesign.16ThiscustomdesignisembeddedintotheoveralldesignFPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimNowthatthelogicwasimplemeArithmeticOperationsandLogicCircuitsArithmeticcalculationsusinghardwarebinarybitsrequirespecialattentiontodatawidthchange.Forexample,multiplyingtwo16-bitnumbersresultsa33-bitanswer,i.e.increasingdatawidth.Inourpre-processingalgorithm,16-bitrealinputdataareexpandedto25-bitcomplexoutputthroughtheFFTlogiccircuit.This25-bitcomplexoutputisagainexpandedto51-bitwhencalculatingtheabsolutevalue.Finally,accumulatingthese51-bitabsolutevaluesfor10ktimescanwidentheirwidthsto64-bit.Datawidthincreaserequiresdesignmodificationsuchaschoosingrightsizebuffersandproperinterpretationwhenreadingstreamedoutputdata.17FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimArithmeticOperationsandLogiAutocorrelation(AnalogComplexDemodulator)Pre-ProcessingAlgorithmTheobjectiveofusingthistechniqueistocalculatetheauto-correlationofthereceivedsignals,whichcanthenbeusedtoestimatetheFFTandproducethepowerspectrumofanydesiredrangegate.Changingrangegates(varyingspatialresolution)isanadvantagethatpreviousFFTpre-processingalgorithmdoesnothave.Inthistechnique(autocorrelation),digitizedreceivedsignalsaresplitintotwopaths.Thefirstpathismixedwithacosinesignaloscillatingat84MHztoproduceanin-phase(I)component;theotherpathismixedwithasinesignaloscillatingat84MHztoproduceaquadrature(Q)component.18FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimAutocorrelation(AnalogCompleIn-Phase(I)andQuadrature(Q)signals’generation19FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimIn-Phase(I)andQuadrature(QAutocorrelationPre-ProcessingAlgorithmThiscircuitblockgeneratesthein-phasesignalcomponentbymultiplyingtheinputtimedomaindigitizedsignals(8ksamplesvector)byan8ksamplevectorconsistingofcos(2πfc),wherefc=84MHz.ThiscosinevectorisgeneratedusingasingleportRAMXilinxblockAdigitalcountercircuitisusedtodrivetheaddressportoftheRAMblocksothateachsampleoftheinputdatavectorismultipliedbyitscorrespondingindexedpointofthecosinevector.Thedatavalidcontrolsignal,whichisassociatedwitheachinputsample,isbeingusedasanenablecontroltothedigitalcountercausingthecountertoincrementeachtimeanewsamplearrives.Theoutputofthiscircuitistheinputsignalsmultipliedbythecosinevector,in-phase(I)component.Similarly,thequadrature(Q)componentisgeneratedusingasingleportRAMXilinxblockstoringan8ksamplevectorofsin(2πfc),wherefc=84MHz.20FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimAutocorrelationPre-ProcessingAutocorrelationDigitalCircuit21------------------FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimAutocorrelationDigitalCircuiAutocorrelationDigitalCircuit22FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimAutocorrelationDigitalCircuiVerticalwindvelocityvs.heightandtimemeasuredon8/17/20112314:37 15:37 16:37 ESTFPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimVerticalwindvelocityvs.heiAtmosphericbackscatteredsignalpowervs.heightandtimemeasuredon8/17/20112414:37 15:37 16:37 ESTFPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimAtmosphericbackscatteredsignAtmosphericbackscatteredrangecorrectedsignalpowervs.heightandtimemeasuredon8/17/20112514:37 15:37 16:37 ESTFPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimAtmosphericbackscatteredrangDirectDetectionCoherentDetectionSignalStrengthRangecorrectedsignalpowervs.heightandtimecomparedwith1μmdirectdetectionmeasuredon8/17/2011DirectCoherentSignalStrengthR

Verticalrangeofdisplayisslightlyover3kmBothlidarsshowtheovercastconditionat14:35andthecloudpatchesat15:55and16:25withgoodagreementwithcloudheightsBothlidarsshowgraduallyincreasingaerosolsignalasafunctionoftime27FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimComparing1microndirectdetectionto1.5microncoherentdetection

27FPGAProgrammingforRealTVerticalwindvelocityvs.heightandtimemeasuredonon8/18/201115:39 16:39 17:39 ESTVerticalwindvelocityvs.heiAtmosphericbackscatteredsignalpowervs.heightandtimemeasuredon8/18/20112915:39 16:39 17:39 ESTFPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimAtmosphericbackscatteredsignAtmosphericbackscatteredrangecorrectedsignalpowervs.heightandtimemeasuredon8/18/20113015:39 16:39 17:39 ESTFPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimAtmosphericbackscatteredrangVerticalwindvelocityandrangecorrectedsignalpowervs.heightandtimemeasuredon8/2/20113117:57 18:27 18:57 (EST)FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimVerticalwindvelocityandranVerticalwindvelocity,signalpower,andrangecorrectedsignalpowervs.heightandtimemeasuredon8/4/20113217:08 17:3818:08 (EST)FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimVerticalwindvelocity,signalVerticalwindvelocity,signalpower,andrangecorrectedsignalpowervs.heightandtimemeasuredon6/24/20123318:21 18:5119:21 (EST)FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimVerticalwindvelocity,signalVerticalwindvelocity,signalpower,andrangecorrectedsignalpowervs.heightandtimemeasuredon6/27/20123416:00 17:0018:0019:21 (EST)FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimVerticalwindvelocity,signalHorizontalwindspeedvstimeandheightandverticalwindvelocitymeasuredonDec.5th,201135FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimHorizontalwindspeedvstimeBackscatteredsignalspowerandrangecorrectedpowervs.heightandtimemeasuredonDec.5th,201136FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimBackscatteredsignalspoweranFFTsignalprocessingvs.Autocorrealtion37FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimFFTsignalprocessingvs.AutoThankyou

QuestionsFPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.Abdelazim38Thankyou

QuestionsFPGAProgrFPGAProgrammingforRealTimeAnalysisofLidarSystemsDr.SamehAbdelazimAssistantProfessor,TheSchoolofComputerSciencesandEngineering,FairleighDickinsonUniversityD.Santoro,M.Arend,F.Moshary,S.AhmedFPGAProgrammingforRealTimeOUTLINEIntroductionMotivationFPGAProgrammingMethodologyLogicDesignImplementationTestingandVerificationHardwareDevelopmentFPGAProgrammingforCoherentDopplerLidarforWindSensingSignalProcessingAlgorithmsFFTI-QDemodulation(Autocorrelation)ResultsFPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.Abdelazim40OUTLINEIntroductionFPGAPrograINTRODUCTIONRealtimeanalysisofLidarsystemsrequiresprocessingofbackscatteredsignalsinstantaneouslyastheyareacquired.BackscatteredsignalscanbeprocessedusingsoftwaresuchasMATLABoncetheyareobtainedbydataacquisitiondevices.Whathappensiftheprocessingrateisunabletokeepupwiththerateatwhichbackscatteredsignalsarereceived.FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.Abdelazim41INTRODUCTIONRealtimeanalysisToprocessbackscatteredsignalsinrealtime,signalprocessingalgorithmswillbeprogrammedintotheFieldProgrammableGateArray(FPGA),sothatbackscatteredsignalsareprocessedrightafterbeingacquired(Co-Processor).SignalprocessingDataacquisition42FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimFPGAforRealTimeAnalysisSignalprocessingDataacquisitFPGAPROGRAMMINGMETHODOLOGYAsignalprocessingalgorithmisinitiallyimplementedasalogicdesign,whichcanbesimulatedandtestedusingMATLAB/Simulinksoftware.ThelogicdesignisthencompiledusingXilinxsystemgeneratortoolsettoproduceahardwareVLSIimage,whichcanbedownloadedintotheFPGA.FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.Abdelazim43FPGAPROGRAMMINGMETHODOLOGYAAccumulatorcircuitFPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.Abdelazim44AccumulatorcircuitFPGAPrograMatlab/SimulinkdesignFunctionverification45FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimAccumulatorcircuitMatlab/SimulinkdesignFunctionPowerSpectrumCalculationFPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.Abdelazim46Powerspectrumofbackscatteredtimedomainsignalscanbeestimatedusingdigitalcircuits(FFTlogiccircuitblock)andbeimplementedontheFPGA.ThecomplexoutputoftheFFTblockisthenmultipliedbyitscomplexconjugatetoobtainthesquaremodulesofthepowerspectrum.PowerSpectrumCalculationFPGPowerSpectraAccumulationAccumulationdigitalcircuitoftheFFToutput(powerspectrum)asimplementedontheFPGA.InthisdesignaFIFOblockisusedasaRAMandthewholedesignactslikearing,whereapowerspectrumvectorof8kcirclestheringuntilanewvectorarrives,thenthestoredvectorisreadfromtheFIFOandaddedtothenewlyarrivedvector.TheresultisthenstoredintotheFIFOuntilanewvectorarrives,andsoon.Thisaccumulationprocesswillbeperformeduntilthecountercircuit(Accumulatorblock)countsto10kX8192samples,whichmeansarrivalof10klasershots,thennewlyarrivedpowerspectraareignoredandstoredaccumulateddataarestreamedouttoanoutputbufferbeforeitisstreamedtothehostPC.FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.Abdelazim47PowerSpectraAccumulationAccuPowerSpectraAccumulationFPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.Abdelazim48PowerSpectraAccumulationFPGALow-Pass(FIR)filterDigitalCircuit49FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimThefrequencyresponseshowsthattheoutofbandsignals(above50MHz)willbesuppressedbyapproximately80dB.Low-Pass(FIR)filterDigitalLow-Pass(FIR)filterDigitalCircuitAXilinxFIRcompiler5.0circuitblockisbeingusedtoperformthistask.TheFIRfilterisdesignedusingMATLAB/Simulinkwithfrequencyresponseshownininthepreviousslide.50FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimLow-Pass(FIR)filterDigitalFPGAProgrammingforCoherentDopplerLidarforWindSensingLidarsystemsemployingfiberlaseroperateatlowenergyperpulse.Therefore,pulserepetitionfrequency(PRF)isincreasedtoobtainhighsignaltonoiseratio(SNR).HighPRFmakesrealtimeanalysisusingonlyadataacquisitioncardandsoftwaresuchasMATLABnearlyimpossible,becausethetimebetweenpulsesisverysmall.

FieldProgrammableGateArrays(FPGAs)offerasolutionforrealtimeanalysis.FPGAalsohelpstoreducetheamountofdatatransferredfromthedataacquisitioncardtothesystem(usuallyaPC).FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.Abdelazim51FPGAProgrammingforCoherentCoherentDopplerLidarSystemA20KHzPFRanda14-bitADCwithasamplingrateof400MHz(eachpulseis50µsandcontains20,000samples),datatransferratefromthedataacquisitioncardtothehostPCwillbe800Mbyte/sec.Thehighdatatransferrateisdifficulttobeachievedandrequiresadditionalhardwareandsoftware.Moreover,theamountofdatacollectedin1daywillbemorethan69Tbyte,whichmakesdataarchivingforjustafewdaysnearlyimpossible.DuetothefastPFR,signalprocessingonthehostcomputercannotbeachievedinrealtime,andwillcausedatatobelost.52FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimCoherentDopplerLidarSystemAFFTPre-processingAlgorithmFPGAlogiccircuitsrunat250MHzclock,therefore,twosamplesarestackedtogethertoforma32-bitwordinordertoachievea400Msamples/secflowrate.A32-bitwordhastobebrokenintoitsoriginaltwo16-bitsamplestoallowfordataanalysis.Thisisaccomplishedbyusinga32-bitto16-bitconvertercircuit.Downconvertingdatasamplesfrom32-bitto16-bitwilllowerthedataflowrate,andasaresult,willleadtosamplesoverflowandeventuallydataloss.Toovercomethisproblem,aframesizeofonly8192samplesisacquiredateveryrisingedgeofanexternaltriggersignalthatissynchronizedwiththesignaldrivingthelaserpulses.Asaresult,only8ksamplescanbeacquiredbytheADCateachpulse.Thisallowsfordatadown-conversionwithoutanydataloss,however,itlimitstherangedistancetoapproximately3.1km.53FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimFFTPre-processingAlgorithmFPNowthatthelogicwasimplementedandtestedforproberoperation,itwillbeembeddedwiththelargerdataacquisitionlogicdesign.54ThiscustomdesignisembeddedintotheoveralldesignFPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimNowthatthelogicwasimplemeArithmeticOperationsandLogicCircuitsArithmeticcalculationsusinghardwarebinarybitsrequirespecialattentiontodatawidthchange.Forexample,multiplyingtwo16-bitnumbersresultsa33-bitanswer,i.e.increasingdatawidth.Inourpre-processingalgorithm,16-bitrealinputdataareexpandedto25-bitcomplexoutputthroughtheFFTlogiccircuit.This25-bitcomplexoutputisagainexpandedto51-bitwhencalculatingtheabsolutevalue.Finally,accumulatingthese51-bitabsolutevaluesfor10ktimescanwidentheirwidthsto64-bit.Datawidthincreaserequiresdesignmodificationsuchaschoosingrightsizebuffersandproperinterpretationwhenreadingstreamedoutputdata.55FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimArithmeticOperationsandLogiAutocorrelation(AnalogComplexDemodulator)Pre-ProcessingAlgorithmTheobjectiveofusingthistechniqueistocalculatetheauto-correlationofthereceivedsignals,whichcanthenbeusedtoestimatetheFFTandproducethepowerspectrumofanydesiredrangegate.Changingrangegates(varyingspatialresolution)isanadvantagethatpreviousFFTpre-processingalgorithmdoesnothave.Inthistechnique(autocorrelation),digitizedreceivedsignalsaresplitintotwopaths.Thefirstpathismixedwithacosinesignaloscillatingat84MHztoproduceanin-phase(I)component;theotherpathismixedwithasinesignaloscillatingat84MHztoproduceaquadrature(Q)component.56FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimAutocorrelation(AnalogCompleIn-Phase(I)andQuadrature(Q)signals’generation57FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimIn-Phase(I)andQuadrature(QAutocorrelationPre-ProcessingAlgorithmThiscircuitblockgeneratesthein-phasesignalcomponentbymultiplyingtheinputtimedomaindigitizedsignals(8ksamplesvector)byan8ksamplevectorconsistingofcos(2πfc),wherefc=84MHz.ThiscosinevectorisgeneratedusingasingleportRAMXilinxblockAdigitalcountercircuitisusedtodrivetheaddressportoftheRAMblocksothateachsampleoftheinputdatavectorismultipliedbyitscorrespondingindexedpointofthecosinevector.Thedatavalidcontrolsignal,whichisassociatedwitheachinputsample,isbeingusedasanenablecontroltothedigitalcountercausingthecountertoincrementeachtimeanewsamplearrives.Theoutputofthiscircuitistheinputsignalsmultipliedbythecosinevector,in-phase(I)component.Similarly,thequadrature(Q)componentisgeneratedusingasingleportRAMXilinxblockstoringan8ksamplevectorofsin(2πfc),wherefc=84MHz.58FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimAutocorrelationPre-ProcessingAutocorrelationDigitalCircuit59------------------FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimAutocorrelationDigitalCircuiAutocorrelationDigitalCircuit60FPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimAutocorrelationDigitalCircuiVerticalwindvelocityvs.heightandtimemeasuredon8/17/20116114:37 15:37 16:37 ESTFPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimVerticalwindvelocityvs.heiAtmosphericbackscatteredsignalpowervs.heightandtimemeasuredon8/17/20116214:37 15:37 16:37 ESTFPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimAtmosphericbackscatteredsignAtmosphericbackscatteredrangecorrectedsignalpowervs.heightandtimemeasuredon8/17/20116314:37 15:37 16:37 ESTFPGAProgrammingforRealTimeAnalysisofLidarSystemsby:Dr.S.AbdelazimAtmosphericbackscatteredrangDirectDetectionCoherentDetectionSignalStrengthRangecorrectedsignalpowervs.heightandtimecomparedwith1μmdirectdetectionmeasuredon8/17/2011DirectCoherentSignalStrengthR

Verticalrangeofdisplayisslightlyover3kmBothlidarsshowtheovercastconditionat14:35andthecloudpatchesat15:55and16:25withgoodagreementwithcloudheightsBothlidarsshowgraduallyincreasingaerosolsignalas