学科分类
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106 个结果
  • 简介:Whitenoisedeconvolutionorinputwhitenoiseestimationproblemhasimportantappli-cationbackgroundsinoilseismicexploration,communicationandsignalprocessing.Bythemoderntimeseriesanalysismethod,basedontheAuto-RegressiveMovingAverage(ARMA)innovationmodel,underthelinearminimumvarianceoptimalfusionrules,threeoptimalweightedfusionwhitenoisedeconvolutionestimatorsarepresentedforthemultisensorsystemswithtime-delayedmeasurementsandcoloredmeasurementnoises.Theycanhandletheinputwhitenoisefusedfiltering,predictionandsmoothingproblems.Theaccuracyofthefusersishigherthanthatofeachlocalwhitenoiseestimator.Inordertocomputetheoptimalweights,theformulaofcomputingthelocalestimationerrorcross-covariancesisgiven.AMonteCarlosimulationexampleforthesystemwith3sensorsandtheBernoulli-Gaussianinputwhitenoiseshowstheireffectivenessandperformances.

  • 标签: 现代时间序列分析方法 白噪声滤波 延迟测量 反卷积 测量噪声 信息融合
  • 简介:Theproblemofadaptivefuzzycontrolforaclassoflarge-scale,time-delayedsystemswithunknownnonlineardead-zoneisdiscussedhere.Basedontheprincipleofvariablestructurecontrol,adesignschemeofadaptive,decentralized,variablestructurecontrolisproposed.Theapproachremovestheconditionsthatthedead-zoneslopesandboundariesareequalandsymmetric,respectively.Inaddition,itdoesnotrequirethattheassumptionsthatallparametersofthenonlineardead-zonemodelandthelumpeduncertaintyareknownconstants.Theadaptivecompensationtermsoftheapproximationerrorsareadoptedtominimizetheinfluenceofmodelingerrorsandparameterestimationerrors.Bytheoreticalanalysis,theclosed-loopcontrolsystemisprovedtobesemi-globallyuniformlyultimatelybounded,withtrackingerrorsconvergingtozero.Simulationresultsdemonstratetheeffectivenessoftheapproach.

  • 标签: 时滞系统 自适应变结构控制 离散控制 非线性死区
  • 简介:Toeliminatethealiasingthatappearedduringthemeasurementofmulti-componentsnonstationarysignals,anovelkindofanti-aliasingalgorithmbasedontheshorttimeFouriertransform(STFT)isbroughtforward.Firstthephysicalessenceofaliasingthatoccursisanalyzed;secondtheinterpolationalgorithmmodelissetupbasedontheHammingwindow;thenthefastimplementationofthealgorithmusingtheNewtoniterationmethodisgiven.Usingthenumericalsimulationthefeasibilityofalgorithmisvalidated.Finally,theelectricalcircuitexperimentshowsthepracticalityofthealgorithmintheelectricalengineering.

  • 标签: 不稳定信号 插值 图形保真 STFT 迭代算法
  • 简介:Inlongtermevolution(LTE)uplinksinglecarrierfrequencydivisionmultipleaccess(SC-FDMA)system,therestrictionthatmultipleresourceblocks(RBs)allocatedtoausershouldbeadjacent,makestheresourceallocationproblemhardtosolve.Moreover,withthepracticalconstraintthatperfectchannelstateinformation(CSI)cannotbeobtainedintime-varyingchannel,theresourceallocationproblemwillbecomemoredifficult.Inthispaper,anefficientresourceallocationalgorithmisproposedinLTEuplinkSC-FDMAsystemwithimperfectCSIassumption.Firstly,theresourceallocationproblemisformulatedasamixedintegerprogrammingproblem.Thenanefficientalgorithmbasedondiscretestochasticoptimizationisproposedtosolvetheproblem.Finally,simulationresultsshowthattheproposedalgorithmhasdesirablesystemperformance.

  • 标签: SC-FDMA 电信 信号处理系统 通信
  • 简介:Thetime-frequencyanalysisofthesignalacquiredbyasingleground-basedmicrophoneshowsatwo-dimensionalinterferencepatterninthetime-frequencyplane,whichiscausedbythetimedelayofthereceivedsignalemittedfromalowflyingaircraftviathedirectpathandtheground-re-flectedpath.Amodelisdevelopedforestimatingthemotionparametersofanaircraftflyingalongastraightlineataconstantheightandwithaconstantspeed.MonteCarlosimulationresultsandex-perimentalresultsarepresentedtovalidatethemodel,andanerroranalysisofthemodelispresentedtoverifytheeffectivenessoftheestimationschemeadvocated.

  • 标签: 飞行器 运动参数估计 曲线拟合 地面被动声学传感器 多路径时间延迟 干扰
  • 简介:Inthispaper,thedesignofsignalconstellationsparametersisstudiedforDifferentialUnitarySpace-TimeModulation(DUSTM)basedonthedesigncriterionofmaximizingthediversityproduct.Further,nonintegersearchingmethodforthesignalconstellationparametersdesignisproposedinordertogetbettercodes.ExperimentalresultsshowthatunderthedifferentDopplerspreadanddatatransmissionrate,theproposeddesignperformsbetterthanthepreviousdesignusingintegerparametersinMultipleInputMultipleOutputOrthogonalFrequencyDivisionMultiplexing(MIMO-OFDM)systemoverfrequency-selectivefadingchannels.

  • 标签: 信号处理 酉空间 衰落信道 频率