外文翻译原文-一种无线温度监测系统的设计与分析

RSM2013Proc.2013,Langkawi,MalaysiaDesignandAnalysisofaWirelessTemperatureMonitoringSystemNorAlinaKhairi1,AsralBahariJambek2andTeohWeiBoon3,UdaHashim41,2,3SchoolofMicroelectronicEngineering,UniversitiMalaysiaPerlis,Malaysia.4InstituteofNanoelectronicEngineering,UniversitiMalaysiaP,2.my,3,4.myAbstractThispaperdiscussesthedesignofawirelesstemperaturemonitoringsystemforindustrialapplication.Thetemperaturesensordetectsthesurroundingtemperaturebeforetransmittingittoareceiver.Atthereceiver,thetemperaturewillbedisplayedonaliquidcrystaldisplayandportablecomputersforeaseofmonitoring.Thispaperhighlightsthedesignandverificationmethodtoensuretheaccuracyofthesensingandtransmittingofdata.Inordertoensuretherobustnessofthesystem,thedevicehasbeentestedinvariousenvironmentandobstacle.Theresultshowsthatthedevicecanaccuratelysenseandmonitortemperaturewithexcellentaccuracy.Keywords:Temperaturesensor;Wireless;RemoteSystem;SensorMonitoring.I.INTRODUCTIONWirelessdeviceswillbeimportantinfuturemonitoringapplicationssuchasinautomobiles1,machines,homeautomation2andbuildings3,forexample,industrialmachineryandequipmentrequiredtobeplacedinoperatingcondition.Inordertomaintainandmonitorthemachineataspecifictemperature,informationneedstobegatheredfromatemperaturesensordevice.Byusinganeffectivetemperaturemonitoringsystem,temperaturevaluescanberecordedinrealtimeordisplayedonamonitor.Theserecordedtemperaturescanbeusedfurthertoanalysetheperformanceofthemachineduringaspecificperiodoftime.Therearemanychallengeswhendesigningwirelesssensordevicessuchastheaccuracyofmeasureddataanddatalossduringtransmission.Buildingawirelesstemperaturemonitoringsystemwillbeexpensive,especiallywhencontinuousrealtimemonitoringisneeded.Typically,awirelesssensorcommunicationsystemcanbedesignedusingZigbee,SensorTag4orBluetoothdevicestotransmitandreceivethedata.Therestofthepaperwillbediscussedasfollows.First,theexistingtechniquetodesignthewirelessmonitoringsystemwillbediscussedinSectionII.ThemethodtodesignthewirelesstemperaturemonitoringsystemwillthenbediscussedinSectionIII.ResultsobtainedfromtheexperimentwillbediscussedinSectionIV.Finally,SectionVwillconcludethepaper.II.LITERATUREThecurrentmarketismovingtowardwirelesstechnologyduetoitsconveniencecomparedtowired-basedsystems5.Thissectionwillreviewexistingmethodsfordesigningwirelesstemperaturemonitoringsystems.Reference6discussestheapplicationoftemperaturedataacquisitionandmonitoringforasensornetworkusingZigBee.Thisworkusesathermocoupleasasensorinput,whereitisconnectedtoacoldjunctioncompensatoramplifier.Afterpassingthroughanamplifier,thesignalisfedintoananalog-to-digitalconverter(ADC)portattheZigBeemodule.ThetemperaturedatawillbetransmittedusingZigbeeprotocoltoapersonalcomputer(PC)atarateoffoursamplingspersec.Awirelesssensornetworkforhealthmonitoringisdiscussedin7.ThissystemusesanetworkanditssubsystemstotransmitdatatothebaseserverbeforetransmittingittoaPDAorpersonalcomputer.8discussesremotemonitoringforagricultureusingawirelesssensorandshortmessageservice(SMS).ThissystemsendsSMSmessagestothefarmerwhenthefarmstemperatureiseithertoohighortoolow.Theobjectiveof9istodesignahealthmonitoringsystemforawirelessbodyareanetwork(WBAN).Inthisproject,ActiSsensorsareusedtomonitoraheartratesignalbeforetransmittingthesignaltoapersonalserverthroughawirelesslocalareanetwork(WAN).Thewirelesstemperaturemonitoringsystemdiscussedin10usesanactiveRFID-basedsystemtocollectdatafromlocationsworldwide.Inthisproject,thesensordetectsthetemperatureandtriggersthealarmwhenthetemperatureistoohighortoolowandsendsthedatawirelesslytothemainserver.Whilemostofthesedeviceshavehighdataacquisitionrates,theyareexpensive.Inthiswork,alowcosttemperaturesensortransmitterandreceiverwerebuilt.Topreventdatalossduringtransmission,bitcheckingmethodwasimplementedtoensurehighmeasurementaccuracy.III.METHODOLOGYFig.1showstheoverallblockdiagramofthelowcostwirelesstemperaturesensorsystem.Themaincomponentsusedinthisworkconsistofamicrocontroller,ananalogtodigitalconverter(ADC)temperaturesensor,atransceiver,areceiver,anencoderandadecoder.First,thetemperaturesensorwilldetecttheroomtemperatureandinputthedatatoanADC.TheADCwillconverttheanalogsignaltodigitalformforthemicrocontrollertoprocessthedata.Thentheprocesseddatawillbesenttoanencoderbeforeitistransmitted.Thereceiverwillreceivetheencodeddataandpassittothedecodertorecovertheoriginaldata.Themicrocontrollerwill105978-1-4799-1183-7/13/$31.002013IEEERSM2013Proc.2013,Langkawi,MalaysiaprocessthedatabeforedisplayingthedataonalaptopcomputerorLCD.Themainwirelesscomponentsarethetransmitter(TX433)andreceiver(RX433).Forthemicrocontroller,P89V51RD2ischosen,whichfallsunderthe8051microcontrollerfamily.Thismicrocontrollerhasfour8-bitinputandoutputports,whichcansupportvariousinputandoutputconfigurations.Table1showsthesummaryofthekeyfeaturesforthemicrocontroller11.Inthiswork,twomicrocontrollerareusedasatransmitterandreceiver.Themainfunctionofthemicrocontrollerinthetransmittermoduleistoconvertthe8-bitdatafromADCto4-bitwidth.Thisallowsthedatatobeencodedbytheencoder.Foreaseofdebugging,theencoderoutputisalsoconnectedtoLCDtodisplaythecurrenttemperaturevaluethatisbeingtransmitted.ThesecondmicrocontrollerprocessesthereceiveddataanddisplaysthetemperaturevalueontoaportablecomputerorLCD.ThisworkusestheLM35fromNationalSemiconductorasthetemperaturesensor.Theadvantageofthissensorisitproducesoutputvoltagethatisproportionaltotemperature(Celsius).Furthermore,ithasalargetemperaturedetectionrangefrom55to+150C12.Theradiofrequencytransmitterisconnectedtoapowersupply,anoscillator,amodulatorandamplifiersforradiofrequencytransmission.Theradiofrequencytransmitterusesafrequency-modulatedcrystaltomodulatethesignalinformationontothecarrierfrequency,whichwillbetransmittedthroughtheairtothereceiver.Thetransmitterissmallandhasalowpowerrequirement,butcancoveralargedistance,amaximumof50meters.Fig.2showstheoverallschematicdiagramforthetransmittermodule.Thesoftwaredevelopmentinthisprojectisdividedinto2parts.TheseareassemblyprogramminglanguagefortemperaturesensordataprocessingandVisualBasicprogrammingsoftwaretodisplaythevalueoftemperatureonacomputer.Anassemblylanguageisoneoftheimportantprogramsthathadbeenuseinthisproject.Toensurethereceiveddataisaccurate,asimpledatacheckingmethodisusedasfollows.First,beforethetemperaturevalueistransmitted,themicrocontrollerdividesthe8bitsofdatainto4pairasshowninTable2.Theencoderwillusetheoriginal2bitsandwilladdanadditional2bitsascheckerbit.Thereceiverwillrecoverthedatausingthereverseprocedure.Table3showstheexampleofatransmittingtemperatureof31oCbyusingthemethodmentioned.IV.RESULTANDDISCUSSIONThefollowingsectiondiscussestheexperimentdonetoverifythewirelesstemperaturesensorfunctionality.First,theresultsofthetemperaturesensorcalibrationwillbediscussed.Next,theverificationonADCfunctionalitywillbehighlighted.Theresultoftheradiofrequencytransmissionaccuracywillbepresentednext.Finally,theoverallsystemperformancewillbediscussed.Fig.3showstheresultofoutputvoltageatvarioustemperaturesforthetemperaturesensor.Basedontheroomtemperature,at28oC,theoutputvoltageis284mv.Thecollecteddatashowevery1oCintemperaturechangeequalto10mVchangeoutputvoltage.(a)(b)Fig.1:Blockdiagramofthewirelesstemperaturemonitoringsystem.(a)(b)Fig.2:Overallschematicdiagramforthewirelesstemperaturesensorsystem(a)transmittermodule(b)receivermodule.106RSM2013Proc.2013,Langkawi,MalaysiaTABLE1SUMMARYOFKEYFEATURESFORP89V51RD211.KeyFeaturesP89V51RD2OperatingFrequencyDC0-40MHzFlashProgramMemory64KDataMemory1024bytesI/OPorts4(8-bitI/Oportswith3high-currentPort1pins(16mAeach)Timers3(16-bit)InterruptEightinterruptsourceswithfourprioritylevelsSerialCommunicationsSPIandenhancedUARTPowerModesPower-downmodewithexternalinterruptwake-upandIdlemodeCapture/ComparefunctionsPCAwithPWMTABLE28BITSBINARYNUMBERANDITSRESPECTIVECHECKERBIT.MSBLSBBitposition2726252423222120Binaryrepresentationfor31oC00011111Checkerbit11100100TABLE3BIT-CHECKINGMETHODTOTRANSMITBINARYDATA.CheckerBitBinaryrepresentationfor31OCCheckerbitandoriginalbinarybit0011(LSB)001101110111100110011100(MSB)1100ToverifytheADCfunction,thetemperatureisvariedtogeneratevariousoutputvoltagesattheADCinput.Table4showstheresultofconvertinganaloginputtodigitaloutputvoltageatthevariousinputtemperatures.TheADCwillproducing8bits,anumberthatrepresentstheequivalenttemperaturevalue.Thedatatransmissioncircuitrymoduleconsistsofanencoder,transmitter,receiveranddecoder.FourLEDsareconnectedatboththeencoderanddecodertoallowvisualinspectionofthetransmitteddata.Table5showstheresultofdatatransmissionaccuracy.Fromthetable,thedatatransmissionmoduleachieves98.3%accuracy.Table6,7and8showtheresultofvariousmeasurementsdoneusingthewirelesstemperaturesensoratvarioustemperatureconditions,distancesandobstacles.Inthisexperiment,dataaretransmittedcontinuouslyforoneminute.Thedatareceivedatthereceiveraremonitoredforanyerrors.Theexperimentisdoneinthreeconditions;openair,twodifferentroomsandtwodifferenthouses.FromTable6,onlytwoerrorsoccurwithin1minutewhentransmittingthedatainopenairforadistanceof5m.Theerrorsoccurduetoinsufficientcurrentsupplytothedevices.Thisproblemhasbeensolvedbyusinganadditionbatteryinthesystem.Afteraddinganadditionalbattery,thedeviceshowsnoerrorasshowninTable7and8.Thetableshowsthatoncethewirelessdeviceobtainedenoughcurrentfromthebattery,thedevicecanworkwellwithvariousdistancesandobstacles.Fromthetable,100%accuracyisachievedforanenvironmentwithobstacles.Fig.4(a)and(b)showthefullimplementationforthetransmitterandreceivermodule,respectively.EachofthecomponentsinthefigureislabelledasshowninTable9and10.Fig.3:Outputvoltagetemperaturesensorversustemperaturereading.TABLE4DIGITALOUTPUTVOLTAGERESULTSVin(mV)Temperature(Celsius)LEDatPin11-18223220001011030930000111134834001000103843800100113994000101000TABLE5COMPARISONBETWEENENCODERINPUTANDDECODEROUTPUTPatternsendforencoderNoofdatatransferNoofcorrectdatareceivedNoofwrongdatareceived001020200111120200001120191110020200010120200101020191Totaldata1201182TABLE6RESULTSOBTAINEDFROMOPENAIR(NOOBSTACLE)Distance(inmeter)Errorsobtainedwithin1minute105215050TABLE7RESULTSOBTAINEDFROMTWODIFFERENTROOMS(WITHONEWALLASANOBSTACLE)Distance(inmeter)Errorsobtainedwithin1minute105015050107RSM2013Proc.2013,Langkawi,MalaysiaTABLE8RESULTOBTAINEDFROMTWODIFFERENTHOUSES(WITHSEVERALWALLSASOBSTACLES)Distance(inmeter)Errorsobtainedwithin1minute105015050(a)(b)Fig.4:FullSchematicfor(a)Transmitter(b)ReceiverV.CONCLUSIONSWirelessdevicesarethemostpopularapplicationsintodaysconsumermarket.Theaimofthisworkistodesignalowcostaccuratewirelesstemperaturemonitoringsystem.Thedevicecanperformtemperaturesensing,andtransmitandreceivethedata.Theresultshowsthatthewirelesstemperaturesensorcanperformaccuratelyinvariousconditionsandatvariousdistances.Amaximum50-meterdistancecanbeusedtotransmitthetemperaturebyusing5voltinputpower.Thenextpartoftheworkwillinvestigatereducingthesizeandoperatingvoltagetoensurethedevicecanbeusedinalowpowerenvironment.TABLE9COMPONENTSINTRANSMITTERPARTASSHOWNINFIG.4(A)NoComponents(model)1LCD(DS-LCD-JHD162A)2Microcontrollerboard(P89V51RD2)3Temperaturesensor(SN-LM35DZ)4Encoder(IC-HT-12E)5ADC(IC-ADC-0804)6Transceiver(RF-TX-433)7LED8Variableresistance(1k)9Antenna10ResetbuttonTABLE10COMPONENTSINRECEIVERPARTASSHOWNINFIG.4(B).NoComponent1LCD(DS-LCD-JHD162A)2Microcontrollerboard(P89V51RD2)3Decoder(IC-HT-12D)4Receiver(RF-RX-433)5LED6RX2327AntennaREFERENCES1Tavares,J.,Velez,F.J.,Ferro,J.M.,“Applicationofwirelesssensornetworkstoautomobiles,”MeasurementScienceReview,Vol.8,Secion3,pp:65-70,2008.2“ZigBeeHomeAutomationPublicApplicationProfile”,ZigBeeAlliance,Rev25,Ver1.0,2007.3Yu,Y.,Prasanna,V.K.,Krishnamachari,B.,“InformationProcessingandRoutinginWirelessSensorNetworks,”WorldScientificPublishingCo.,2006.4“ZigbeeSensorTagDataSheet”,PultronicsInc.5GeorgeW.Irwin,JeremyColandairajandWilliamG.Scanlon,“AnOverviewofWirelessNetworksinControlandMonitoring,”InternationalConferenceonIntelligentComputing(CHINE2006),Vol.4114,pp.1061-1072,2006.6CaiBin,JinXinc