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外文资料及中文译文学生姓名付木木（200702031031）专业电子信息工程指导教师姓名王木木专业技术职务高级实验师外文资料MovingObjectCountingwithanInfraredSensorNetworkByKI,ChiKeungAbstractWirelessSensorNetwork(WSN)hasbecomeahotresearchtopicrecently.GreatbenefitcanbegainedthroughthedeploymentoftheWSNoverawiderangeofapplications,coveringthedomainsofcommercial,militaryaswellasresidential.Inthisproject,wedesignacountingsystemwhichtrackspeoplewhopassthroughadetectingzoneaswellasthecorrespondingmovingdirections.Suchasystemcanbedeployedintrafficcontrol,resourcemanagement,andhumanflowcontrol.Ourdesignisbasedonourself-madecost-effectiveInfraredSensingModuleboardwhichco-operateswithaWSN.ThedesignofoursystemincludesInfraredSensingModuledesign,sensorclustering,nodecommunication,systemarchitectureanddeployment.WeconductaseriesofexperimentstoevaluatethesystemperformancewhichdemonstratestheefficiencyofourMovingObjectCountingsystem.Keywords:Infraredradiation，WirelessSensorNode1.1IntroductiontoInfraredInfraredradiationisapartoftheelectromagneticradiationwithawavelengthlyingbetweenvisiblelightandradiowaves.Infraredhavebewidelyusednowadaysincludingdatacommunications,nightvision,objecttrackingandsoon.Peoplecommonlyuseinfraredindatacommunication,sinceitiseasilygeneratedandonlysufferslittlefromelectromagneticinterference.TaketheTVremotecontrolasanexample,whichcanbefoundineveryone'shome.Theinfraredremotecontrolsystemsuseinfraredlight-emittingdiodes(LEDs)tosendoutanIR(infrared)signalwhenthebuttonispushed.Adifferentpatternofpulsesindicatesthecorrespondingbuttonbeingpushed.ToallowthecontrolofmultipleappliancessuchasaTV,VCR,andcablebox,withoutinterference,systemsgenerallyhaveapreambleandanaddresstosynchronizethereceiverandidentifythesourceandlocationoftheinfraredsignal.Toencodethedata,systemsgenerallyvarythewidthofthepulses(pulse-widthmodulation)orthewidthofthespacesbetweenthepulses(pulsespacemodulation).Anotherpopularsystem,bi-phaseencoding,usessignaltransitionstoconveyinformation.EachpulseisactuallyaburstofIRatthecarrierfrequency.A'high'meansaburstofIRenergyatthecarrierfrequencyanda'low'representsanabsenceofIRenergy.Thereisnoencodingstandard.However,whileagreatmanyhomeentertainmentdevicesusetheirownproprietaryencodingschemes,somequasi-standardsdoexist.TheseincludeRC-5,RC-6,andREC-80.Inaddition,manymanufacturers,suchasNEC,havealsoestablishedtheirownstandards.WirelessSensorNetwork(WSN)hasbecomeahotresearchtopicrecently.GreatbenefitcanbegainedthroughthedeploymentoftheWSNoverawiderangeofapplications,coveringthedomainsofcommercial,militaryaswellasresidential.Inthisproject,wedesignacountingsystemwhichtrackspeoplewhopassthroughadetectingzoneaswellasthecorrespondingmovingdirections.Suchasystemcanbedeployedintrafficcontrol,resourcemanagement,andhumanflowcontrol.Ourdesignisbasedonourself-madecost-effectiveInfraredSensingModuleboardwhichco-operateswithaWSN.ThedesignofoursystemincludesInfraredSensingModuledesign,sensorclustering,nodecommunication,systemarchitectureanddeployment.WeconductaseriesofexperimentstoevaluatethesystemperformancewhichdemonstratestheefficiencyofourMovingObjectCountingsystem.1.2WirelesssensornetworkWirelesssensornetwork(WSN)isawirelessnetworkwhichconsistsofavastnumberofautonomoussensornodesusingsensorstomonitorphysicalorenvironmentalconditions,suchastemperature,acoustics,vibration,pressure,motionorpollutants,atdifferentlocations.Eachnodeinasensornetworkistypicallyequippedwithawirelesscommunicationsdevice,asmallmicrocontroller,oneormoresensors,andanenergysource,usuallyabattery.Thesizeofasinglesensornodecanbeaslargeasashoeboxandcanbeassmallasthesizeofagrainofdust,dependingondifferentapplications.Thecostofsensornodesissimilarlyvariable,rangingfromhundredsofdollarstoafewcents,dependingonthesizeofthesensornetworkandthecomplexityrequirementoftheindividualsensornodes.Thesizeandcostareconstrainedbysensornodes,therefore,haveresultincorrespondinglimitationsonavailableinputssuchasenergy,memory,computationalspeedandbandwidth.Thedevelopmentofwirelesssensornetworks(WSN)wasoriginallymotivatedbymilitaryapplicationssuchasbattlefieldsurveillance.Duetotheadvancementinmicro-electronicmechanicalsystemtechnology(MEMS),embeddedmicroprocessors,andwirelessnetworking,theWSNcanbebenefitedinmanycivilianapplicationareas,includinghabitatmonitoring,healthcareapplications,andhomeautomation.1.3TypesofWirelessSensorNetworksWirelesssensornetworknodesaretypicallylesscomplexthangeneral-purposeoperatingsystemsbothbecauseofthespecialrequirementsofsensornetworkapplicationsandtheresourceconstraintsinsensornetworkhardwareplatforms.Theoperatingsystemdoesnotneedtoincludesupportforuserinterfaces.Furthermore,theresourceconstraintsintermsofmemoryandmemorymappinghardwaresupportmakemechanismssuchasvirtualmemoryeitherunnecessaryorimpossibletoimplement.TinyOS[TinyOS]ispossiblythefirstoperatingsystemspecificallydesignedforwirelesssensornetworks.Unlikemostotheroperatingsystems,TinyOSisbasedonanevent-drivenprogrammingmodelinsteadofmultithreading.TinyOSprogramsarecomposedintoeventhandlersandtaskswithruntocompletion-semantics.Whenane