ZigBee外文文献加翻译.docx

ZigBee外文文献加翻译.docx

《ZigBee外文文献加翻译.docx》由会员分享，可在线阅读，更多相关《ZigBee外文文献加翻译.docx（15页珍藏版）》请在冰豆网上搜索。

ZigBee外文文献加翻译

ACoalMineEnvironmentalMonitorSystemwithLocalizationFunctionBasedonZigBee-CompliantPlatform

DongxuanYang

CollegeofComputerandInformation

Engineering

BeijingTechnologyandBusiness

University

Beijing,China

YanChen

CollegeofComputerandInformation

Engineering

BeijingTechnologyandBusiness

University

Beijing,China

*****************

KedongWang

CollegeofComputerandInformation

Engineering

BeijingTechnologyandBusiness

University

Beijing,China

Abstract—Thispaperdescribesandimplementsanewtypeofcoalminesafetymonitoringsystem,itisakindofwirelesssensornetworksystembasedonZigBeetechnology.Thesystemconsistsoftwopartsundergroundandsurface.Wirelesssensornetworksareconstitutedbyfixednodes,mobilenodesandagatewayinunderground.PCmonitoringsoftwareisdeployedinthesurface.Thesystemcannotonlygatherreal-timeenvironmentaldataformine,butalsocalculatethereal-timelocationofmobilenodeswornbyminers.

Keywords：

ZigBee;localization;wirelesssensornetworks;coalMine

.RESEARCHSTATUS

Asanimportantenergy,coalplaysapivotalroleintheeconomicdevelopment.Coalminemonitoringsystem,istheimportantguaranteeforcoalminesafetyandhighefficiencyproduction[1].Inordertoensurethesafeoperation,theinstallationofenvironmentmonitoringnodeintunnelstoreal-timedetectionisveryimportant.However,commonlyusedtraditionalmonitoringnodewiredconnectiontoobtaincommunicationwiththecontrolsystem,thisnodeexistwiringdifficulties,expensiveandothershortcomings.Incontrast,wirelesssensornodecanbeeasilywithcurrentminemonitoringnetworkconnection,andgoodcompatibility,facilitateconstitutedminegasmonitoringnetwork,tosuitvarioussizeofmineapplications.Sincewirelessnodesarebatterypowered,socompletelyoutoftheshacklesofthecable,shortentheconstructionperiodcanbearrangedatanytimewheretheneedtouse.

TheZigBeewirelesscommunicationtechnologyisusedinthiscoalmineenvironmentalmonitorsystem.Thisisanewshort-range,lowcomplexity,lowpower,lowdatarate,low-costtwo-waywirelesscommunicationtechnology[2].Now,wirelesssensornetworkproductbasedonZigBeetechnologyarequantityandvariety,buttherealproductcanbeappliedinundergroundenvironmentsofspecialsensornodeisveryfew[3].Thesensornodethatwedesignedinthesystemistrulyabletoapplytoin-wellenvironment,itthroughthewirelesssensornodesecuritycertification.Atthesametime,duetothespecialnatureofthewirelessnetworkisthatitcanspreadthewirelesssignal,wecaneasilylocatestaffforcoalminesafetymonitoringprovidesmoreprotection[4].

.SYSTEMARCHITECTURE

Thissystemisacomprehensivemonitoringsystemwhichiscombinedwithsoftwareandhardware.Hardwarepartincludeswirelessmobilenodesandfixednodeswhichweredeployedintheundergroundtunnel,themainfunctionofthemistocollectcoalmineenvironmentdataandrequireperson’slocation.SoftwarepartreferstothePCmonitoringsoftwarewhichisdesignedinVC++isusedtosummarizeanddisplaythedataofeachnode.Monitoringnodeisdividedintomobilenodesandfixednodes;theyareusingZigBeeprotocolforwirelesstransmissionofdata.Becausethefixednodeisalsousingwirelessdatatransmissionmethod,soit'sdeployedintheundergroundroadwaybecomesveryconvenient.Asthemobilenodeiscarriedbytheminer,itmustbeusingwirelesstransmissionmethod.ThisallowstheminetoformatopologyofZigBeewirelesssensornetwork.Thefixednodeinwirelesssensornetworkisrouterdeviceandthemobilenodecarriedbymineristheenddevice.Normally,therouterofZigBeenetworkhasnosensorequipment;itisonlyresponsiblefordataforwarding.Butconsideringthepracticalapplication,webelievethataddsensordevicesontherouterwillbebetteronmonitoringundergroundcoalmineenvironment.Soinourdesign,therouteralsohasanenvironmentmonitoringfunctionwhichisusuallydesignedinenddevice.

Fixednodewillsentreceiveddatafrommobilenodetothegateway,thenthegatewaytransmitsdatatomonitorcomputerthroughRS232oropticalfiber.ThePCmonitorsoftwareinthecomputerwillprocessalldataanddisplaytheminavisualizationwindow.ThePCsoftwarealsocalculateseachmobilenode’sreal-timelocationthroughthespecificlocalizationalgorithm,accordingtothereceivedsignalstrength（RSSI）obtainedfrommobilenodes.

.NODEDESIGN

SincetheZigBeewirelessnetworkplatformsoldonpresentmarketwasdesignedforthegeneralenvironment,forspecialundergroundsotheyarenotsuitablefortheenvironment.Therefore,weneedtocustomizethesystemforundergroundenvironmentwhitaspecialhardwarecircuit.NodephotoareshowninFig.1

ThenwirelessmicrocontrollerCC2530chipisthecoreprocessorofthenodedevice,itcanconstituteaZigBeenetworkwithveryfewperipheralcircuits.TheCC2530isanIEEE802.15.4complianttrueSystem-on-Chip,supportingtheproprietary802.15.4marketaswellastheZigBee,ZigBeePRO,andZigBeeRF4CEstandards.Unlikeotherwirelesschip,CC2530built-in8051monolithicintegratedcircuitskernel,thereforewenolongerneedtouseasingleMCUtocontrolthecircuit,andthissaveusalotofcost[5].

A.MobileNode

ThemobilenodeistheenddeviceofaZigBeenetworkthatcanbecarriedbyminer;itshouldbeaportableandlowpowerconsumptionnode.Sothemobilenodewedesignedisonlyassmallasamobilephone,anditisbybuilt-inlithiumionbatterypowersupply.Inpowerloss,thecoreprocessorCC2530isalowpowerconsumptionchip,whenitisinthesleepmode,itonlyneedtouselessthen1uAworkcurrent.Inordertoreducepowerconsumptionasmuchaspossibleonthedisplay,a100*32pixelmatrixwithnobacklightingLCDscreenwasused.Thebattery’scapacityofthemobilenodeis1500mAh,soitisenoughtomeettheminer’slonghourworksintheunderground.ThebatterychargemanagementchipisTP4057,themaximumchargecurrentcanupto500Ma.

Figure1.Nodephoto.

ThemobilenodecircuitincludesthegasconcentrationsensorMJ4.0andtemperaturesensorPT-1000.Asfarasweknow,manywirelesssensorplatformsusethedigitaltypesensor.ThecommunicationbetweenthedigitalsensorandtheMCUneedstricttimingrequirements.Butconsideringtheactualapplication,thewirelessMCUusuallyhasareal-timeoperatingsystemingeneral,ifweusethemicrocomputertosimulatethestricttiming,itwillaffectthereal-timeofwholeoperatingsystem.Thesetwosensorsoutputanalogsignalsnotdigitalsignals.Onlyinputthissignalintoadifferentialamplifier,canwegetanappropriatesignalthatcanbeconvertedtoadigitalsignalbyanADCmodewithintheCC2530chip.Inordertofacilitatethecarrying,externalantennawasnotusedinourmobilenode,insteadofusinga2.4GHzpatchantenna.Andwecustomizeashelllikeacellphonesize;itisenoughtoputallPCBs,sensorsandbatteryinit.Takingintoaccountthesmallshelloftheexplosiveperformanceisnotverygood,thedesignofPCBsandtheselectionofcomponentareallcarriedoutthesafetyassessment.

B.FixedNode

Fixednodeisinstalledinthewalloftheundergroundtunnel.Becauseitisbigthanthemobilenode,itisnotappropriatetocarryaround.Thecircuitofthefixednodeisalmostsamewiththemobilenode,italsouseaCC2530chipascoreprocessor.Becauseofundergroundtunnelsgenerallydeploywithpowercable,fixednodescanusecablepower-supplymodes.Atthesametime,becauseweusewirelesssignaltransmission,thedeploymentofnewfixednodesbecomeveryconvenient,whichalsoresolvestheproblemofthesignallinesdeployment.

Asafixednode,theminorwhoisdoingworkmayfarfromit,inordertofacilitatetheminersobservedenvironmentaldataaroundthefixednodes,itusesLEDdigitaldisplay.Atthesametime,thelargecurrentLEDlightsandbuzzeraredesignedinthecircuit;itmakesthefixednodewiththefunctionofsound-lightalarm.Consideringthatitmayoccurtheemergencyofwithoutelectricity,fixednodealsobuilt-inalithium-ionbattery.Undernormalconditions,lithium-ionbatteryisinchargingstatus,whenexternalcabledisconnect,fixednodeisautomaticswitchedtobatterypower,whichcanensurethemobilenodecandelivertheinformationthroughfixednodesinunderground.

Withoutregardingtofixednodes’portability,wehaveacustomizedshellthathasexcellentexplosionproperties,andtheinternalspaceisenoughtoholddownthe2.4GHzantenna.Toensuresafety,allcablesandthelocationofsensorsareplacedwithparticulargluesealed,sothatithasagoodseal.

.POSITIONINGFUNCTION

Oneoftheimportantfunctionsofthewirelesssensornetworksislocalization,especiallyintheundergroundtunnel,itrelatestothesafeoftheminer'slife.CurrentlymostwidelyusedorientationmethodisGPSsatellitepositioning,itisahighprecision,all-weatherandglobalmultifunctionalsystemwiththefunctionofradionavigation,positioningandtiming.ButtheGPSpositioningmethodisnotsuitablefortheundergroundworkenvironmentofcoalmine,onceyouentertheunderground,itcannotreceivesatellitesignal,thusunabletoachievetargeting[6].Weneedtoconsiderhowtousewirelessnetworktorealizepositioningfunction,meansusingwirelesssignalbetweenthecommunicationsofdevicesforpositioning.Theexistingdistancemeasuringtechnologybetweenthewireless-devicesbasicallyisthefollowingkindsofmethods:

TOA,TDOA,AOAandRSSI.

AbouttheTOAmethod,thedistancebetweenthetwodevicesisdeterminedbythep