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  • 简介:RadarSystemEngineering¥DaleR.Billetter(RaytheonCompany,Massachusetts.USA)WHATISRADARSYSTEMENGINEERING?Anorganizationdesiredto...

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  • 简介:Ubiquitousradarisanewradarsystemthatprovidescontinuousanduninterruptedmultifunctioncapabilitywithinacoveragevolume.Continuouscoveragefromclose-in'pop-up'targetsincluttertolong-rangetargetsimpactsselectionofwaveformparameters.Thecoherentprocessinginterval(CPI)mustbelongenoughtoachieveacertainsignal-to-noiseratio(SNR)thatensurestheefficiencyofdetection.TheconditionofdetectioninthecaseoflowSNRisanalyzed,andthreedifferentcasesthatwouldoccurduringintegrationarediscussedandamethodtodeterminetheCPIispresented.ThesimulationresultsshowthattargetsdetectionwithSNRaslowas-26dBintheexperimentalsystemcanpossiblydeterminetheCPI.

  • 标签: 多普勒雷达 雷达信号 低信噪比 物价指数 信号噪声比 雷达系统
  • 简介:PrologtotheSectiononRadarSystemEngineering¥//IntheEnglishlanguagewehaveanexpressionthatsaysitispossible"tolosesightofthefores...

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  • 简介:ApplicationofSuperresolutionTechniquestoRadarImagingA.Fanrina,F.Prodi&F.Vinelli(Alenia.UnaAziendaFinmeccanica.Radar&C2Divisio...

  • 标签: RADAR IMAGING SAR ISAR ERS- 1
  • 简介:714SDDOPPLERWEATHERRADARSYSTEM¥GeRunsheng(葛润生),ZhangPeiyuan(张沛源)andPengHong(彭红)714SDDOPPLERWEATHERRADARSYSTEMGeRunsheng(葛润生),...

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  • 简介:Duetothegoodperformanceoftrackinglowelevationtargetascomparedtomicrowaveandthesuperiorityinpenetratingsmoke,dust,fog,anddrysnowascomparedtoinfrared,aKuandKadualbandexperimentalradarwasdesignedanddeveloped.ThisKuandKadualbandexperimentalradarisanarnplitute-comparisonmonopulsetrackingandguidingradar.Theconstitutionandparametersofthisradarisdescribedinparagraph2.Paragraph3dealswithtwoexperimentsfortestingthetrackingperformancesagainstlowelevationtarget,andgivestheimportantresults.BothKuandKabandhavehightrackingprecisionwhentheytrackhighelevationtargets,whileKabandhasmuchbettertrackingperformancethanKubandwhentheytracklowelevationtargets.Kabandcantrackahelicopter,whoseradarcrosssectionisabout6squaremeters,at40m,20m,10m,andeven5mabovesea.Kubandcanonlytrackthesamehelicopterat160mandhigherabovesea.

  • 标签: MILLIMETER wave RADAR KU and KA
  • 简介:不同于在行星的边界层的风骚乱光谱上的以前的研究,这调查集中于高高度(15km)在各种各样的天气下面的风精力光谱和骚乱光谱调节。快Fourier变换(快速傅里叶变换)被用来基于风介绍在高高度(15km)计算风精力和骚乱光谱密度雷达(WPR)大小。在在高高度的稳定的天气条件下面的骚乱光谱在2的一个频率范围以内在力量被表示吗??

  • 标签: 风廓线雷达 频谱分析 雷达测量 高海拔地区 快速傅立叶变换 天气条件
  • 简介:以便在实际侦察环境解决emitter识别问题,属性数学被介绍。属性集合和属性措施的基本概念和理论详细被描述。基于属性,措施在这篇论文被介绍的一个新属性识别方法。申请例子被给,它表明这个新方法精确、有效。而且,为认出emitter目的计算机摸拟;计算机模拟被选择,并且与通过模拟的古典统计模式识别相比。优秀试验性的结果证明这作为与存在统计模式识别技术相比是一个崭新的属性识别方法。

  • 标签: 属性测量 识别标准 雷达 发射器
  • 简介:Themainfunctionofelectronicsupportmeasuresystemistodetectthreatingsignalsinordertotakecountermeasuresagainstthem.Toaccomplishthisobjective,aprocessofassociatingeachinterleavedpulsewithitsemittermustbedone.Thisprocessistermedsortingorde-interleaving.Anovelpointsymmetrybasedradarsorting(PSBRS)algorithmisaddressed.Inordertodealwithallkindsofradarsignals,thesymmetrymeasuredistanceisusedtoclusterpulsesinsteadoftheconventionalEuclideandistance.Thereferencepointsofthesymmetricalclustersareinitializedbythealternativefuzzyc-means(AFCM)algorithmtoamelioratetheeffectsofnoiseandthefalsesorting.Besides,thedensityfiltering(DF)algorithmisproposedtodiscardthenoisepulsesorclutter.Theperformanceofthealgorithmisevaluatedundertheeffectsofnoiseandmissingpulses.IthasbeenobservedthatthePSBRSalgorithmcancopewithalargenumberofnoisepulsesanditiscompletelyindependentofmissingpulses.Finally,PSBRSiscomparedwithsomebenchmarkalgorithms,andthesimulationresultsrevealthefeasibilityandefficiencyofthealgorithm.

  • 标签: SORTING radar PULSE SYMMETRY ALTERNATIVE fuzzy
  • 简介:PreliminaryresultsofthewindvelocityestimationusingtheMaximumEntropyMethod(MEM)toMUradarobservationdatasetsarepresented.ThecomparisonoftheresultsfromtheperiodogrammethodandtheMEMshowsthattheMEMestimationisreliable,andhashigheraccuracy,resolutionanddetectabilitythantheestimationfromperiodogrammethod.ThehighaccuracypowerspectrumobtainedbytheMEMisveryusefultostudyingtheatmosphericturbulencestructure.However.theMEMneedsthelongercomputingtimeforobtainingthehighaccuracyspectrum.Particularly,theestimationofMEMwillbringseriousdevia-tionatlowersignal-to-noiseratio.

  • 标签: the Maximum ENTROPY METHOD (MEM) the
  • 简介:Adopting'simultaneoustransmitting,simultaneousreceiving'operationalscheme,instantaneouspolarizationradar(IPR)canmeasuretargetpolarizationscatteringmatrix(PSM)usingonlyoncetargetechoesintwoorthogonalpolarizationchannels.Firstly,signalmodelandsignalprocessareadvancedundernarrowbandcondition.Secondly,measurementperformancesoftwotypicalIPRwaveformsareanalyzedindetail.Atlast,fieldexperimentsarecarriedoutusingX-bandIPRsystemdesignedbyNationalUniversityofDefenseTechnology(NUDT),China.Comparedwithresultsobtainedbyalternativepolarizationmeasurementscheme,followingresultscanbeobtained:thedifferenceofrelativeamplitudemeasurementresultsissmallerthan2dBandthatofrelativephasemeasurementresultsissmallerthan10?,verifyingthevalidityofinstantaneouspolarizationmeasurementscheme.

  • 标签: 极化散射矩阵 测量方法 雷达目标 知识产权制度 国防科学技术大学 瞬时
  • 简介:AnewSuboptimalMaximumLikelihoodEstimation(SMLE)algorithmbasedonfull-derampmodelanditsimplementationinsatellite-borneradaraltimeterarepresented,withemphasisontheinfluenceofboththereturnfluctuationandthereceivernoiseonheightandslopeestimationprecision.Someconclusionsareobtainedandverifiedbycomputersimulation.

  • 标签: Satellite-borne RADAR ALTIMETER Signal processing SMLE
  • 简介:雷达生气的节(RCS)是一个目标的反射力量的测量。减少一艘海军的轮船的RCS启用它的迟了的察觉,它为利用吃惊和行动的元素是有用的。因此,一艘海军的轮船的RCS为完成吃惊,行动,和survivability成为了一个很重要的设计因素。因而,精确RCS决心和RCS减小具有为一艘海军的轮船的极端重要性。这份报纸的目的是提供理论背景和工程途径的理解为海军的轮船处理RCS预言和减小。RCS,雷达基础,RCS基础,RCS预言方法,和为海军的轮船的RCS减小方法的重要性也被讨论。

  • 标签: 雷达散射截面 海军舰艇 预测 RCS减缩 雷达横截面 反射强度
  • 简介:Anoptimizationmethodisbasedtodesignasnowfallestimatemethodbyradarforoperationalsnowwarning,anderrorestimationisanalyzedthroughacaseofheavysnowonMarch4,2007.Threemodifiedschemesaredevelopedforerrorscausedbytemperaturechanges,snowflaketerminalvelocity,thedistancefromtheradarandcalculationmethods.Duetotheimprovements,thecorrelationcoefficientbetweentheestimatedsnowfallandtheobservationis0.66(exceedingthe99%confidencelevel),theaveragerelativeerrorisreducedto48.74%,andthemethodisabletoestimateweaksnowfallof0.3mm/handheavysnowfallabove5mm/h.Thecorrelationcoefficientis0.82betweentheestimatedsnowfallfromthestations50to100kmfromtheradarandtheobservation.Theimprovedeffectisweakwhentheinfluenceofthesnowflaketerminalvelocityisconsideredinthosethreeimprovementprograms,whichmayberelatedtotheuniformecho.Theradarestimateofsnow,whichisclassifiedbythedistancebetweenthesampleandtheradar,hasthemostobviouseffect:itcannotonlyincreasethedegreeofsimilarity,butalsoreducetheoverestimateandtheundervaluationoftheerrorcausedbythedistancebetweenthesampleandtheradar.Theimprovedalgorithmfurtherimprovestheaccuracyoftheestimate.Theaveragerelativeerrorsare31%and27%fortheheavysnowfallof1.6to2.5mm/handabove2.6mm/h,respectively,buttheradaroverestimatesthesnowfallunder1.5mm/handunderestimatesthesnowfallabove2.6mm/h.Radarechomaynotbesensitivetotheintensityofsnowfall,andtheconsistencyshownbytheerrorcanbeexploitedtoreviseandimprovetheestimationaccuracyofsnowforecastintheoperationalwork.

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  • 简介:侦察混血儿雷达信号的一条参数评价途径联合了调音的频率移动(频移键控),调音的阶段移动(PSK)被介绍。第一,多相的差别被采用计算即时频率(如果)FSK/PSK,那么,频移键控的频率点从直方图被估计如果。PSK的代码率从阶段断绝的地点被提取。最后,收到的信号的平方的多相的差别被计算估计频移键控的代码率。当signal-to-noise比率(SNR)在11dB上面时,介绍算法有参数评价的更高的精确性。

  • 标签: 参数估计方法 雷达信号 FSK PSK 相移键控 频移键控
  • 简介:3-D雷达反射率数据向对流规模在数据吸收为使用变得日益重要数字天气预言以及下一代降水评价。典型地,从多重雷达的反射率数据客观地被分析并且mosaiced到地区性的3-D上在被吸收进模型以前的笛卡儿的格子。与多雷达观察的马赛克联系的科学问题之一是所有观察的同步。后来,雷达数据很快通常被更新(∼every510min),由假设暴风雨在窗口以内是稳定的在一个时间窗口以内联合多重radar'观察在当前的多雷达马赛克技术是普通的。假设为慢发展降水系统成立很好,要不是快发展对流暴风雨,这个假设可以被违背,在不同时间的雷达观察的马赛克可以导致不精密的暴风雨结构描写。这研究用追踪算法的多尺度的暴风雨在多重雷达数据分析在暴风雨结构上调查同步的影响。

  • 标签: 暴雨云团 多尺度识别方法 临近预报 层级聚类法
  • 简介:Windshearreflectsthatthewindfieldisnotuniform,whichisoneoftheprimaryfactorswhichmaketheretrievalofthewindfielddifficult.Basedonvolumevelocityprocess(VVP)windfieldretrievaltechnique,theintensityofwindshearisidentifiedinthispaper.Afteranalyzingthetraditionaltechniquesthatrelyonthedifferenceofradialvelocitytoidentifywindshear,afixeddifferenceamongradialvelocitiesthatmaycausefalseidentificationinauniformwindfieldwasfound.Becauseofthenon-uniformityinwindshearareas,thedifferenceofretrievedresultsbetweensurroundinganalysisvolumescanbeusedasameasurementtoshowhowstrongthewindshearis.AccordingtotheanalysisofasevereconvectiveweatherprocessthatoccurredinGuangzhou,itcanbefoundthattheareasofwindshearappearedwiththestrengthsignificantlylargerthaninotherregionsandthemagnitudegenerallylargerthan4.5m/(s·km).Besides,bycomparingthevariationofwindshearstrengthduringtheconvection,itcanbefoundthatnewcellswillbemorelikelytogeneratewhenthestrengthisabove3.0m/(s·km).Therefore,theanalysisofstrongwindshear'smovementanddevelopmentishelpfultoforecastingsevereconvections.

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  • 简介:Featurereductionisakeyprocessinpatternrecognition.Thispaperdealswiththefeaturereductionmethodsforatime-shiftinvariantfeature,powerspectrum,inRadarAutomaticTargetRecognition(RATR)usingHigh-ResolutionRangeProfiles(HRRPs).Severalexistingfeaturereductionmethodsinpatternrecognitionareanalyzed,andaweightedfeaturereductionmethodbasedonFisher'sDiscriminantRatio(FDR)isproposedinthispaper.AccordingtothecharacteristicsofradarHRRPtargetrecognition,thisproposedmethodsearchestheoptimalweightvectorforpowerspectraofHRRPsbymeansofaniterativealgorithm,andthusreducesfeaturedimensionality.Comparedwiththemethodofusingrawpowerspectraandsomeexistingfeaturereductionmethods,theweightedfeaturereductionmethodcannotonlyreducefeaturedimensionality,butalsoimproverecognitionperformancewithlowcomputationcomplexity.Intherecognitionexperimentsbasedonmeasureddata,theproposedmethodisrobusttodifferenttestdataandachievesgoodrecognitionresults.

  • 标签: 雷达 目标自动识别 RATR 分辨率 能量光谱