简介:TheadvantageofATMtechnologyforstatisticallymultiplexingnetworkresourcesbydifferentusersinvokesthecompetitionofnetworkresources.Thiscompetitionhassomedamagingeffectsonmessagetransmitting.TheresearchfortestingmethodsandtechnologyofATMisimportantforustodevelopATMnetworks,topromotetheirconstruction,toensurethatvariousATMdevicesprovidedbydifferentprovidersinteroperateproperlyandtoprovideexcellentservicesfortelecommunicationusers.Afterdiscussingtheabstracttestingmethodofconformancetestingandtheabstractdescriptionofprotocoltesting,thethesisputsforwardakindofabstracttestingconfigurationforATMtestingandakindofabstractdescriptionmethodfortestingcase.Fromtheangleofapplication,thethesisdiscussesthebasicrulesforATMtesting.Afterthat,thethesispointsoutthattheATMtestingmustbemadefromthefouraspectsofnormaltesting,conformancetesting,performancetestingandinteroperabilitytesting.Thegeneraltestingmethods,generalconfigurationandconnectionforATMtestingandtheselectionofATMtestingitemsarediscussed,respectively,inthefouraspects.CombinedwiththecharacteristicsofthetrafficssupportedbyATMsystems,thethesisdiscussesseveralkindsoftrafficmodelsforconductingATMtesting.Onthebasisofstudyingvarioustrafficmodels,theauthorclassifiestrafficmodelsforATMtestingasthreekinds:periodictrafficmodels,stochastictrafficmodelsandmanualtrafficmodels.Theparametersofdescribingtrafficmodelsandtheircalculatingmethodarediscussedinthethesis.Anewkindofperiodiccell-sequencetrafficmodelisproposedinthisthesis.Theperiodiccell-sequencetrafficmodelhasexcellentlinearlydescendingcharacteristicsinthecellinterval.ThetrafficmodelsdiscussedinthisthesiscanbeappliedtovariousATMtestingcases.Fromthepointofnormaltesting,physicallayertesting,ATMlayertesting,AALlayertesting,networkmanagementtesting
简介:Byanalyzingthethreshold-jumpingofSchmittcircuits,thispaperindicatesthatthecoreelementrealizingthisfunctioninbinaryTTLSchmittcircuitsisthedifferentialcurrentswitchwithcontrollablethreshold.Basedonthecharacteristichavingtwokindsofsignal-detectionthresholdinternaryTTLcircuits,aternaryTTLSchmittcircuithavingtwicereactionsofthreshold-jumpingisdesigned.ThesimulationwithPSPICEprovesthatthedesignedcircuithasidealfunctionofSchmittcircuits.
简介:Plasmonicwaveguides,asacompetitivecandidate,havebeenwidelystudiedinrapiddevelopingphotonicintegratedcircuits(PICs)andopticalinterconnectionfields.However,crosstalkbetweenplasmonicwaveguidesisacriticalissuethathastobeconsideredinpractice.Actually,crosstalkdominatestheultimateintegrationdensityoftheplanarphotoniccircuits.Thispaperreviewstherecentresearchworkonevaluationmethodsandcrosstalksuppressionapproachesofplasmonicwaveguides.Threecrosstalkevaluationmethodsbasedoncomparisonofspecificparametersofwaveguideshavebeensummarized.Furthermore,fourspecificapproachestoreducecrosstalkhavebeenillustratedastwocategoriesaccordingtotheirimpactsonwaveguideperformancesandthewholecircuit.Onemeansofcrosstalksuppressionischangingtheplacementofwaveguides,whichcouldmaintainthetransmissioncharacteristicsoftheoriginalwaveguide.Theothermeansisinsertingmedium,whichhastheadvantageofoccupyingsmallerspacecomparedtothefirstmethod.Consequently,tosuppresscrosstalkbetweenplasmonicwaveguides,oneshouldchoosesuitableapproach.
简介:Inthisletter,anovelalgorithmisproposedforidentificationofonepopulartypeofVoIP(VoiceoverIP)application,MSNVoIP,basedonbothbehaviorpatternandprotocolcharacteristics.Inaddition,theexperimentforvalidationisimplemented.SincethereexistsnomethodidentifyingMSNVoIPsessionandfurthermoretheIPaddresses,domainnames,portsandeventheprotocolsMSNPworksover,areallalterableduringtheapplication,whichmakesitdifficulttoidentifyMSNVoIPsession,thisworkwillbehelpfultoadvancetheresearchonVoIPidentification.
简介:Inbandpasssigmadeltamodulator,resonatoristhekeyblock.Thispaperproposedanewresonatorwhichcansimplifythecircuitimplementationwhendesigningbandpassmodulatorwithlowpassprototype.Theeffectoffinitegain,finitebandwidth,andpathmismatchontheresonatorisanalyzed.ThefunctionoftheproposedresonatorandthedeviredequationsaboutpathmismatchhavebeenverifiedbyswitchedcapacitorsoftwareSWITCAP.
简介:Inthispaper,theperfectdyadicbinarysequencepairwithone-valuedyadiccorrelationfunctionsispresented.Thatis,theperfectdyadicbinarysequencepairisaperfectdiscretesignal,foritsdyadicrelativefunctionisδ-function.Thetransformationfeaturesandsomeexistingadmissibilityconditionsofperfectdyadicbinarysequencepairarediscussed,andthepropertiesforthiskindofcodeinWalshtransformationspectrumandweightspectrumarealsoanalyzed.Fromabove,Itisfoundthattheperfectdyadicbinarysequencepaircaneasilydifferentiatefromitsdyadicshifting.Sothesegoodsignalscanusedinengineeringassynchronizationcode,multi-usercodeandsoon.
简介:这篇文章检验危险驱动在软件和密码的算法的硬件实现之间的分析攻击。包括一个Atmel89S82528位处理器和0.25m的代表性的平台1.8v标准房间电路被建议实现进展加密标准(AES)。基于模拟的试验性的环境被造获得力量数据,和单个小点的微分力量分析(DPA),并且多小点DPA和关联驱动分析(CPA)攻击分别地在二实现上被进行。试验性的结果证明硬件实现让更少的数据依赖者驱动漏抵抗力量攻击。而且,一条改进DPA途径被建议。它作为力量模型采用中间的结果的hamming距离并且安排纯文本输入区分力量踪迹到最大的概率。与原来的力量攻击相比,我们的改进DPA与可接受的力量大小和更少计算在AES硬件实现上执行成功的攻击。
简介:TheambiguityresolutioninthefieldofGPSisinvestigatedindetail.Anewalgorithmtoresolvetheambiguityisproposed.Thealgorithmfirstobtainsthefloatingresolutionoftheambiguityaidedwithtripledifferencemeasurement.Decorrelationofsearchingspaceisdonebyreducingtheambiguitycovariancematrix'sdimensiontoovercomethepossiblesickfactorizationofthematrixbroughtbyZ-transformation.Insimulation,theproposedalgorithmiscomparedwithleast-squaresambiguitydecorrelationadjustment(LAMBDA).TheresultshowsthattheproposedalgorithmisbetterthanLAMBDAbecauseoflesserresolvingtime,whichapproximatelyreduces20%resolvingtime.Thus,theproposedalgorithmadaptstothehighdynamicreal-timeapplications.
简介:OnthebasisoftheactualDSPsystemdevelopment,illustratedisthedesignoftheconnectionbetweenDSPandFlash,compiledaretheintegrityproceduresofFlasherasureandprogramming.Besides,designedistheconnectionbetweenfull-duplexEthernetcontrollerRTL8019ASwiththeexternalmemoryinterfaceofDSP.Furthermore,thestepsofflashonlineprogrammingthroughEthernetaredescribedindetail.Theremoteupgradeandupholdarerealizedbythedesign.
简介:Thisarticleisconcernedwiththemodelingandcontrolproblemsoftheflexiblespacecraft.First,thestateobserverisdesignedtoestimatethevibrationmodeonthebasisoffreevibrationmodels.Then,anoptimalguaranteedcostcontrollerisproposedtostabilizesystemattitudeanddampthevibrationoftheflexiblebeamatthesametime.Numericalsimulationexamplesshowthefeasibilityandvalidityoftheproposedmethod.
简介:Theconceptofnetworkcentricwarfare(NCW)anditscharacter,highrequirementofreal-timesynchronizationareintroduced.Thedistributedequal-nodenetworkarchitectureinNCWispresented.Basedontheoreticalanalysisonethemetinterfaceperformance,thispaperpresentsthatforwardinglatencybetweenethemetinterfacedevicesisakeyinfluencefactorofreal-timesynchronizationinNCW.Ethemetfundamentalisbrieflyintroduced.Themodelbetweenaswitchundertest(SUT)andasmartbitscardispresentedandusedfortwointerconnectingswitchesinNCW.Onconditionthatignoringthelatencyofconnectingfiberortwistedpairsandprocessinglatencyofthesmartbitstestsystem,thispaperpresentsthatdockfrequencytolerance(CFT)betweenaSUTandasmartbitscardisaleadinginfluencefactorofforwardinglatencyofanethemetswitch.TheformulaetocalculateinternalforwardinglatencyandforwardinglatencycausedbyitsCFTarededuced.TheoreticalcalculationonforwardinglatencyofanethemetswitchbasedonthegivenCFTandtesttimeisimplemented.ExperimentalstudyonprimaryforwardinglatencyandsecondaryforwardinglatencyisimplementedandforwardinglatencybetweentheSUTandthesmartbitscardismeasured,thustestifyingtheaccuracyoftheabovetheoreticalanalysisthattheCFTisakeyinfluencefactorofforwardinglatency.ThemeasurestosatisfytheneedsofforwardinglatencyinNCWarepresented.
简介:Customers'satisfactionwithservicesisreflectedbyqualityofexperience(QoE).Insofar,moststudiesoncooperativecommunicationhavebeenfocusedonimprovingtheQoEofsourceusers.However,theimprovementofasourceuser'sQoEisobtainedatcostofdegradationoftherelayuser'sQoE.Ontheotherhand,cooperativecommunicationscanachieveperformancesimilartothatofaconventionalmultiple-inputmultiple-output(MIMO)systembyformingvirtualMIMOarrays.Hence,toimprovetheQoEperformanceofrelayusers,thisarticleproposestheconceptofabeliefthresholdatthedestinationuserandanewcooperativeschemebasedonthebeliefthresholddestination(BTD)technique,whilewithoutdecayingtheBERperformanceofthecommunicationsystem.
简介:Inthispaper,thecauseofbit-errorisanalyzedwhendataaredecidedintheopticalreceiver.AmonolithicD-ffdecisioncircuitisdesigned.Itcanworkeffectivelyat622Mb/s.Moreover,adecisionmethodofparallelprocessingtoimprovethddecisionspeedispresented,throughwhichtheparallelcircuitcanworkupto1Gb/susingthesamemodel.Withthetechnique,higher-speeddatacanbedecidedbyusinglowerspeeddevice.
简介:Alasersimulatorisproposedwhichisbasedonahardware-in-loop(HWIL)simulationtestsystem.Asanimportantdeviceinthesimulationtestsystem,itisusedtosimulatethelaserenergyandthedivergenceangle.ThelasersimulatorsimulatestheattenuationprocessoflaserenergybythecontinuousrotationofGlanprismsandthechangingoflaserspotsizethroughthecontinuousmotionofthelaserbeamexpandingtelescopeonthestraightplatform.Thedynamicattenuationvelocityofthelasersimulatorisupto4dB/s,andthedivergenceangleadjustmentvelocityisupto3mrad/s.Themethodisfeasibleforthesimulationtest.
简介:Inthispaper,usedBSO(Bi12SiO20)crystalasahologramrecordingmaterial,TV-cameraasadetector,andaholographicsetupcontrolledbyacomputer,automaticallycalculatinghologramof3-interferogramsmethodistheoreticallyandexperimentallystudied.Thisnewholographicrecordingmaterialandautomaticallycalculatinghologrammakeitpossibletousereal-timeholographyinanindustry.Asapracticalexample,theshrinkingof2-componentsadhesivein4hismeasured.