简介：A2D-directionofarrivalestimation(DOAE)formultiinputandmulti-output(MIMO)radarusingimprovedmultipletemporal-spatialsubspacesinestimatingsignalparametersviarotationalinvariancetechniquesmethod(TS-ESPRIT)isintroduced.InordertorealizetheimprovedTS-ESPRIT,theproposedalgorithmdividestheplanararrayintomultipleuniformsub-planararrayswithcommonreferencepointtogetaunifiedphaseshiftsmeasurementpointforallsub-arrays.TheTS-ESPRITisappliedtoeachsub-arrayseparately,andinthesametimewiththeotherstorealizetheparallellytemporalandspatialprocessing,sothatitreducesthenon-linearityeffectofmodelanddecreasesthecomputationaltime.Then,thetimedifferenceofarrival(TDOA)techniqueisappliedtocombinethemultiplesub-arraysinordertoformtheimprovedTS-ESPRIT.Itisfoundthattheproposedmethodachieveshighaccuracyatalowsignaltonoiseratio(SNR)withlowcomputationalcomplexity,leadingtoenhancementoftheestimatorsperformance.

简介：Satisfactoryresultscannotbeobtainedwhenthreedimensional(3D)targetswithcomplexmaneuveringcharacteristicsaretrackedbythecommonlyusedtwo-dimensionalcoordinatedturn(2DCT)model.Toaddresstheproblemof3Dtargettrackingwithstrongmaneuverability,onthebasisofthemodifiedthree-dimensionalvariableturn(3DVT)model,anadaptivetrackingalgorithmisproposedbycombiningwiththecubatureKalmanfilter(CKF)inthispaper.Throughideologyofreal-timeidentification,theparametersofthemodelarechangedtoadjustthestatetransitionmatrixandthestatenoisecovariancematrix.Therefore,statesofthetargetarematchedinreal-timetoachievethepurposeofadaptivetracking.Finally,foursimulationsareanalyzedindifferentsettingsbytheMonteCarlomethod.Allresultsshowthattheproposedalgorithmcanupdateparametersofthemodelandidentifymotioncharacteristicsinreal-timewhentargetstrackingalsohasabettertrackingaccuracy.

简介：为优化空中交通流的管控策略,研究了空中交通流分布特性。根据厦门1号扇区实测数据,确定了空中交通流的高峰时段,并计算其累积超容比。引进泰尔指数,作为评价空中交通流不均衡度的评价指标。采用多项式回归分析法建立了空中交通流累积超容比-泰尔指数（CT）模型,并进行显著性检验,构建了可接受空中交通流不均衡度（AATFID）模型。研究结果表明,该模型能较好反映空中交通流高峰分布态势,对空中交通管理策略具有重要指导意义。

简介：Thispapercombinescompressedsensing(CS)imagingtheoryandrangemigrationalgorithm(RMA),andthenproposesanear-fieldthree-dimensional(3-D)imagingapproachforjointhigh-resolutionimagingandphaseerrorcorrection.Firstly,asparsemeasurementmatrixconstructionmethodbasedonalogisticsequenceisproposed,whichconductsnonlineartransformationforthedeterminedlogisticsequence,makingitobeyuniformdistribution,thenconductssignfunctionmapping,andgeneratesthepseudorandomsequencewithBernoullidistribution,thusleadingtogoodsignalrecoveryunderdown-samplingandeasyavailabilityforengineeringrealization.Secondly,incombinationwiththeRMAimagingapproach,thedictionarywithallsceneinformationandphaseerrorcorrectionisconstructedforCSsignalrecoveryanderrorcorrection.Finally,thenon-quadraticsolutionmodeljointingimagingandphaseerrorcorrectionbasedonregularizationisbuilt,anditissolvedbytwosteps—theseparablesurrogatefunctionals(SSF)iterativeshrinkagealgorithmisadoptedtorealizetargetscatteringestimate;theiterationmodeisadoptedforthecorrectionofthedictionarymodel,soastoachievethegoaloferrorcorrectionandhighly-focusedimaging.Theproposedapproachprovestobeeffectivethroughnumericalsimulationandrealmeasurementinanechoicchamber.Theresultsshowthat,theproposedapproachcanrealizehigh-resolutionimaginginthecaseoflessdata;thedesignedmeasurementmatrixhasbetternon-coherenceandeasyavailabilityforengineeringrealization.Theproposedapproachcaneffectivelycorrectthephaseerror,andachievehighly-focusedtargetimage.

简介：针对分布式压缩感知中联合稀疏信号的重构问题,在分析了信号群与联合稀疏模型（JSM）基础上,利用JSM-2型联合稀疏信号在子空间内的投影特性,提出了一种多重子空间追踪重构算法.仿真结果表明,该算法在降低计算复杂度的同时可有效确保联合稀疏信号重构准确率.

简介：危机决策模拟训练系统是培养现代军事人才决策实战能力的重要工具。危机决策模拟训练中,社会仿真模型为参训人员构建了一个定性和定量的综合战略研究环境。采用动态演化与静态分析相结合的建模结构,可以更有效地关联危机态势推演进程。针对社会仿真建模中静态分析模型,将经典层次分析法与训练结合,提出了危机决策模拟训练中的综合国力模型,并采用和法进行合理求解,充分运用了施训专家的专业分析判断能力,为参训人员提供了直观可靠的图形结果。

简介：Globalpositioningsystem(GPS)forvehicleapplicationsintheurbanareaischallengedbylowsignalintensity.ThecarrierloopbasedonfastFouriertransform(FFT)canobtainahighsignaltonoiseratio(SNR)gainbyincreasingtheobservationtime.However,thisleadstoamajorproblemthattheaccelerationcannotbeignored.TheperformanceoftheFFT-basedloopwilldeclinewiththeaccelerationincreasing.ThispaperdiscussestheeffectofthedynamiconFFTfirst.ThenahighperformancecarriertrackingloopforweakGPSL5signalsisproposed.Itcombinesdiscretechirp-Fouriertransform(DCFT)andthephasefittingmethodtoestimateDopplerfrequencyandDopplerratesimultaneously.First,asequenceofintegrationresultsisusedtoperformDCFTtoestimatecoarseDopplerfrequencyandDopplerrate.Second,thephaseofthesequenceiscalculatedandusedtoperformlinearfitting.Bythephasefittingmethod,thefineDopplerfrequencyandDopplerratecanbeestimated.ThecomputationcostissmallbecausetheintegrationresultsareusedandthephasefittingmethodneedsonlycoarseestimatesofDopplerfrequencyandDopplerrate.ComparedwithFFTandDCFT,theprecisionofthephasefittingmethodisnotlimitedbytheresolution.Thustheproposedloopcangethighprecisionandlowcarriertonoiseratio(C/N0)trackingthreshold.Simulationresultsshowthisloophasagreatimprovementthanconventionalloopsforurbanweak-signalapplications.

简介：UnipolarresistiveswitchingbehaviorsoftheZnOandAl2O3/ZnOfilmsfabricatedonflexiblesubstratesbypulselaserdepositionwerestudiedinthispaper.Thefilmsweredepositedatroomtemperaturewithoutpost-annealingtreatmentduringtheprocess.XraydiffractionresultsindicatedthatZnOfilmhasadominantpeakat(002).ScanningelectronmicroscopyobservationshowedacolumnargrainstructureoftheZnOfilmtothesubstrate.ThebilayerdeviceofAl2O3/ZnOfilmshadstableresistiveswitchingbehaviorswithagoodenduranceperformanceofmorethan200cycles,highresistiveswitchingratioofover103atareadvoltageof0.1V,whichisbetterthanthatofthesingleoxidelayerdeviceofZnOfilm.Apossibleresistiveswitchingfilamentarymodewasdemonstratedinthispaper.TheconductionmechanismsofhighandlowresistancestatescanbeexplainedbyspacechargelimitedconductionandOhmic’sbehaviors.Theenduranceofthebilayer(BL)devicewasnotdegradeduponbendingcycles,whichindicatesthepotentialoftheflexibleresistiveswitchingrandomaccessmemoryapplications.

简介：Qorvo推出满足LTE2级功率要求的RF前端产品组合，也称作高性能用户设备（HPUE）。集成QorvoRFFE设备的智能手机可兼具高频段频谱的速度与容量优势和中频段频谱的覆盖范围优势。