简介:Thispaperpresentsanoveltimedelayestimation(TDE)methodusingtheconceptofentropy.Therelativedelayisestimatedbyminimizingtheestimatedjointentropyofmultiplesensoroutputsignals.Whenestimatingtheentropy,theinformationaboutthepriordistributionofthesourcesignalisnotrequired.Instead,theParzenwindowestimatorisemployedtoestimatethedensityfunctionofthesourcesignalfrommultiplesensoroutputsignals.Meanwhile,basedontheParzenwindowestimator,theRenyi’squadraticentropy(RQE)isincorporatedtoeffectivelyandefficientlyestimatethehigh-dimensionaljointentropyofthemultichanneloutputs.Furthermore,amodifiedformofthejointentropyforembeddinginformationaboutreverberation(multipathreflections)forspeechsignalsisintroducedtoenhancetheestimator’srobustnessagainstreverberation.
简介:Inthispaper,anewtimingoffsetestimationmethodforOrthogonalFrequencyDivisionMultiplexing(OFDM)systemsarepresented.Uponthereceiptofjustonetrainingsequence,thispresenceofasignalandthestartoftheframecanbedetected.TheperformancesofthetimingestimatorinadditivewhiteGaussiannoiseandthemobilemultipathchannelareevaluatedbysimulation.TheresultsdeliveredbythisalgorithmarecomparedwiththosedeliveredbySchmidlandCox.
简介:Basedonuniformcirculararrayanditselementoutputsignaldelaydelayanovelmethodforestimationofspatialfrequency,azimuthandelevationispresented.Withoutanyspectralpeaksearchandparameterspairing,theresultingmethodis(?)resolutionandsmallvariance,eveninshortdatalength.Computersimulation(?)effectivenessofthismethod.
简介:AnewDirectionOfArrival(DOA)estimationalgorithmforwidebandsourcesbasedonUniformCircularArray(UCA)ispresentedviaanalyzingwidebandperformanceofthegeneralESPRIT.ThealgorithmeffectivelyimprovesthewidebandperformanceofESPRITbasedontheinterpolationprincipiumandUCA-ESPRIT.Thesimulatedresultsbycomputerdemonstrateitsefficiency.
简介:Inthispaper,thesubspacefittingmodelsfordirection-of-arrival(DOA)estimationisanalyzed,aneffectivealgorithmicapproachisgiven.Astheinitializationvalueissocriticaltotheglobalconvergence,thecontinuationtheoryisalsousedtodevelopanewframeworkwhichsolvestheinitializationproblempowerfully.Somenumericalevidencewillbegiventoshowthattheperformanceofthenewalgorithmisverypromising.
简介:BasedonthesinglesensorKalmanfilteringequations,thispaperpresentstwo-levelandthree-leveloptimalcentralizedanddistributedestimationalgorithmsforhierarchicalmultisensorsystems.Thesolutionshowsthatwhenthecorrelatedmatrix,themeanofnoise,thecontrolinput,andthemeasurementerrorareallzero,theresultinthispapertumsouttobethestandardalgorithmdiscussed.Simulationshowsthatthemeanofnoise,thecontrolinput,andthemeasurementerrorwillnotchangetheestimationcovarianceandtheestimationcovariancefluctuatesgreatlywhenthecross-correlatedmatrixissimilartothecovarianceofprocessnoise.
简介:TherearetwomajorapproachesforBlindSignalSeparation(BSS)problem:MaximumEntropy(ME)andMinimumMutualInformation(MMI)algorithms.BasedontherecursivearchitectureandtherelationshipbetweentheMEandMMIalgorithms,anExtendedME(EME)algorithmisproposedbyusingprobabilitydensityfunction(pdf)estimationoftheoutputstodeducethecorrespondingiterativeformulasinBSS.Basedonthesimulationresults,itcanbeconcludedthattheproposedalgorithmhasbetterperformancesthanthetraditionalMEalgorithminconvolutemixtureBSSproblems.
简介:ThispaperintroducesamethodforsolvingDOAestimationambiguityinESPRITalgorithmwiththeconventionalbeamformer.Withthehelpofit,foranyspaceoftwosubarrays,thesignalDOAin[-π/2,π/2]canbeestimatedeffectivelybyusingESPRITalgorithm.Finally,somesimulationresultstoverifythetheoreticalanalysesarepresented.
简介:MotionEstimationBasedonGlobalandLocaCompensabilityAnalysisTXMotionEstimationBasedonGlobalandLocalCompensabilityAnalysisFanJin...
简介:Intheevaluationofsomesimulationsystems,onlysmallsamplesdataaregottenduetothelimitedconditions.Inallusiontotheevaluationproblemofsmallsampledata,anintervalestimationapproachwiththeimprovedgreyconfidencedegreeisproposed.Onthebasisofthedefinitionofgreydistance,threekindsofdefinitionofthegreyweightforeverysampleelementingreyestimatedvalueareputforward,andthentheimprovedgreyconfidencedegreeisdesigned.Inaccordancewiththenewconcept,thegreyintervalestimationforsmallsampledataisdeduced.Furthermore,thebootstrapmethodisappliedformoreaccurategreyconfidenceinterval.Throughresamplingofthebootstrap,numeroussmallsampleswiththecorrespondingconfidenceintervalscanbeobtained.Thenthefinalconfidenceintervaliscalculatedfromtheunionofthesegreyconfidenceintervals.Intheend,thesimulationsystemevaluationusingtheproposedmethodisconducted.Thesimulationresultsshowthatthereasonableconfidenceintervalisacquired,whichdemonstratesthefeasibilityandeffectivenessoftheproposedmethod.
简介:ABayesianestimationmethodtoseparatemulticomponentsignalswithsinglechannelobservationispresentedinthispaper.Byusingthebasisfunctionprojection,thecomponentseparationbecomesaproblemoflimitedparameterestimation.Then,aBayesianmodelforestimatingparametersissetup.ThereversiblejumpMCMC(MonteCarloMarkovChain)algorithmisadoptedtoperformtheBayesiancomputation.Themethodcanjointlyestimatetheparametersofeachcomponentandthecomponentnumber.SimulationresultsdemonstratethatthemethodhaslowSNRthresholdandbetterperformance.
简介:Theproblemofbearingestimationofcoherentsignalimpingiogonanarrayofarbitrarygeometryisstudied.Bothapproachesaredeveloped,thefirstonesynthesizestheobservedarraydataintotheoutputsofalinearuniformarrayandthenprocessesthemviaconventionaltechniquessuchasspatialsmoothingetc.Thesecondapproachisbasedontheinvariantsubspacerotationoperationwhichisequivalenttothetranslationaldisplacementoftheartay,linearlyindependentsignalvectorsareobtainedtherebytospanperfectlythesignalsubspace.Ascomparedwiththeconventionalprocessingtechniques,theapproachbasedoninvariantsubspacerotationdoesnotleadtoaneffectivedecreaseinaperturesizeandthereforeadecreaseinresolutioncapability.Thecomputersimulationsareconductedtodemonstratetheeffectivenessofthepresentedapproaches.
简介:Forthedirectionofarrival(DOA)estimation,traditionalsparsereconstructionmethodsforwidebandsignalsusuallyneedmanyiterationtimes.Forthisproblem,anewmethodfortwo-dimensionalwidebandsignalsbasedonblocksparsereconstructionisproposed.First,aprolatespheroidalwavefunction(PSWF)isusedtofitthewidebandsignals,thentheblocksparsereconstructiontechnologyisemployedforDOAestimation.Theproposedmethodusesorthogonalizationtochoosethematchingatoms,ensuringthattheresidualcomponentscorrespondtotheminimumabsolutevalue.Meanwhile,thevectorsobtainedbyiterationareback-disposedaccordingtothecorrespondingatomicmatchingrules,sotheextraatomsareabandonedinthecourseofiteration,andtheresidualcomponentsofcurrentiterationarereduced.Thustheoriginalsparsesignalsarereconstructed.Theproposedmethodreducesiterationtimescomparingwiththetraditionalreconstructionmethods,andtheestimationprecisionisbetterthantheclassicaltwo-sidedcorrelationtransformation(TCT)algorithmwhenthesnapshotissmallorthesignal-to-noiseratio(SNR)islow.
简介:Compressivesensing(CS)hasemergedasanovelsamplingframeworkwhichenablessparsesignalacquisitionandreconstructionwithfewermeasurementsbelowtheNyquistrate.AnimportantissueforCSistheconstructionofmeasurementmatrixorsensingmatrix.Anewdeterministicsensingmatrix,namedasOOC-B,isproposedbyexploitingopticalorthogonalcodes(OOCs),BernoullimatrixandSingerstructure,whichhastheentriesof0,+1and-1beforenormalization.Wehaveproventhatthedesigneddeterministicmatrixisasymptoticallyoptimal.Inaddition,theproposeddeterministicsensingmatrixisappliedtodirectionofarrival(DOA)estimationofnarrowbandsignalsbyCSarrays(CSA)processingandCSrecovery.TheoreticalanalysisandsimulationresultsshowthattheproposedsensingmatrixhasgoodperformanceforDOAestimation.ItisveryeffectiveforsimplifyinghardwarestructureanddecreasingcomputationalcomplexityinDOAestimationbyCSAprocessing.Besides,lowerrootmeansquareerror(RMSE)andbiasareobtainedinDOAestimationbyCSrecovery.
简介:Alow-complexitymethodfordirectionofarrival(DOA)estimationbasedonestimationsignalparametersviarotationalinvariancetechnique(ESPRIT)isproposed.Insteadofusingthecross-correlationvectorsinmultistageWienerfilter(MSWF),theorthogonalresidualvectorsobtainedinconjugategradient(CG)methodspanthesignalsubspaceusedbyESPRIT.Thecomputationalcomplexityoftheproposedmethodissignificantlyreduced,sincethesignalsubspaceestimationmainlyneedstwomatrixvectorcomplexmultiplicationsattheiterationofdatalevel.Furthermore,thepriortrainingdataarenotneededintheproposedmethod.Toovercomeperformancedegradationatlowsignaltonoiseratio(SNR),theexpandedsignalsubspacespannedbymorebasisvectorsisusedandsimultaneouslyrendersESPRITyieldredundantDOAs,whichcanbeexcludedbyperformingESPRIToncemoreusingtheunexpandedsignalsubspace.ComparedwiththetraditionalESPRITmethodsbyMSWFandeigenvaluedecomposition(EVD),numericalresultsdemonstratethesatisfactoryperformanceoftheproposedmethod.
简介:Inthisletter,capacityestimationforMobileAdhocNETworks(MANETs)usingdirec-tionalantennasarestudied.TwoMatrix-basedFastCalculationAlgorithms(MFCAs)areproposedtoestimatethenetworkcapacityinanetworkscenarioinwhichthereisnochannelsharingamongmultiplesessionsandtrafficissensitivetodelaywithanend-to-enddelayconstraint.Thefirstalgo-rithmMFCA-1isusedtoestimatenetworkcapacityinasituationwherealllinkshavethesamedelay.Itestimatesthemaximumnumberofk-hopsessionsinanetworkbasedonthek-hopadjacencymatrixofthenetwork.ThesecondalgorithmMFCA-2isusedtoestimatenetworkcapacityinasituationwheredifferentlinksmayhavedifferentdelays.Itcalculatesthemaximumnumberofsessionsinanetworkwithanend-to-enddelayconstraintbasedontheadjacencymatrixandthelink-delaymatrixofthenetwork.NumericalandsimulationresultsshowthatbothMFCA-1andMFCA-2cancalculatenetworkcapacitymuchfasterthanthewell-knownBrute-ForceSearchAlgorithm(BFSA)butwiththesameaccuracy.
简介:Thekeyofthesubspace-basedDirectionOfArrival(DOA)estimationliesintheestimationofsignalsubspacewithhighquality.Inthecaseofuncorrelatedsignalswhilethesignalsaretemporallycorrelated,anovelapproachfortheestimationofDOAinunknowncorrelatednoisefieldsisproposedinthispaper.TheapproachisbasedonthebiorthogonalitybetweenamatrixanditsMoore-Penrosepseudoinverse,andmadenoassumptiononthespatialcovariancematrixofthenoise.Theapproachexploitsthestructuralinformationofasetofspatio-temporalcorrelationmatrices,anditcangivearobustandpreciseestimationofsignalsubspace,soapreciseestimationofDOAisobtained.Itsperformancesareconfirmedbycomputersimulationresults.