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：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：12月6日，希捷科技旗下的高端品牌LaCie在北京举办“LaCie，畅想创作之美”智慧媒体存储解决方案暨新品发布会，发布了专门面向专业媒体人士的新一代产品——LaCie2bigDockThunderbolt3，为广大摄影师、视频制作人等媒体工作者提供超大容量、超快速度的两盘位RAID存储，优化创意工作流。

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。

简介：在2016年NAB展览会上,索尼专业推出了4K摄影机新品PXW-FS7M2（下称FS7M2）。作为FS7的升级版,FS7M2增加了无级可调电子ND系统、锁杆型E卡口镜头座、可直接拍摄4K标准色域BT2020、手柄延长臂调整方式改进、标配显示屏遮光罩、增加了电源LED灯等功能,可以看出索尼在FS7M2的细节改进上是非常用心的,充分汲取了大家对前代FS7的使用经验，瞄准痛点，精确改进。DVClub产品测评室就着重为大家测试FS7M2的新亮点。

简介：本文探讨了M~2W型中波发射机自动控制系统的硬件设计原理。