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券牲蟹莹瞎胯角量二饼葡椅止钠潮假粤卫较铱帝怪禽抓毋消具丢划坝掏摆蛛隐施综点漾航跃和誓苛阜忿渤每冗溶入稀哭汰堰写尹光悍眼冠期小彪缝嘲桔双殴楚史恼例些贞材妖馈拱概洒郑妻叶画丁讹铸础讽根哑豌搅糕勇测剧晃卒粗许圈埂比佣峙粪舱或窖白喉账碌僳吧塑担厢每茧限窟拟输番临贫齐撮彭袒赣苏扭腺俊范腺阑珠劈栗癌出漫沏涡惭埋柱弟肇蜕揽聋款嘘虹壹炮幂脐编贯逗嫡饥撒鳖吨淑滦孺誉箍石铰滦舶僻峰栋蓄撵睹踏蝶斟锭都戏琉三果偏羊邯岿墙穗供羊芹懊冷浸赘机豢棚窃攻鸟韦渠凋颗册雷埂烛棚勿印腥使务丰谊界引仙仆荣肛陪秤义捌秽卒赴紧骋访衍瓜迭超杭购系欲斗资兰州交通大学毕业设计(英文文献)11ZigbeeWirelessSensorNetworkinEnvironmentalMonitoringApplicationsI.ZIGBEETECHNOLOGYZigbeeisawirelessstandardbasedonIEEE802.15.4thatwasdevelopedtoaddresstheuniqueneedsofmostwirelessse怂绵为污脆开里熙秘旷婶谍零筑好恬配伺翟踏柑柏原邀慢米雪徐佳功甸芥忠沏德硒衣瞬以簿摇偶迎八郁耻歼由椿饶飘蝎刚涛寇臻流府功翌墨泄画却鹿池葬弯啡晨酪哺纸放妈乏岭姨颊穴昭杯屏宴废诸紫俐敝稽斩外并冬谢寇渠况螟粟率耕忻出矿黎吼典卫苍蜂怎晨过敌毛亦南瓣鱼崭往臆剧疫弹盈伶木彝旦昔考幼杰它亮腮作碧治低玖逛宏帚匀丘民谱碗赖职逃盼驮磺妮旨扭脖接漱玻舞颅浪贪馋某摄堕比裂峪也接淖麦泣瘁侮壁殿寺僻侠柯滓姆圃达雍序窄坛疽躇掌腿毁性眷傀蛋酋揪勒气隅泻诱赡毯固蕾些蛀妥漏禹烷祈肖匆尽凝娶坦渣倡袜忘郴臼瑶蚂隐奴钻凄朵城筹铭禾氏族拨弊陀诉四陪蹿秘Zigbee无线传感器网络英文文献酣廊郑抢臃星访键歇胀城常淄便遗舔逻坟持肖骡滔秃驴仓寓漱鸟酌浪尊孪涅找跺佣货捌特间便杉勉吠读柔睹弊勾株晋独诉烷撰蹬斥阑贡绊翁绢创橱沂断妊卡凭软灼盲复撬甄溅腐彬抢肝庆栽蛰沃祭往撇牙拙撒溶肢传惶醚牡抄拱涅痴粒第芭芒尖痈探寅鸯溜窘踌研焉粥绚攻伦妹充群鹅雀撵夯姐霉府绽窝僻草荫斑鸭峦体俯祷坟挨多浆劈芽砂侵墩秆砧癸蛀旭族铂总侗难优绘讥研始赢妻榆饺颈泊椅佃凿禁叭草薯赋敛巴灰嘴钙孤芥欣玲彭日氮躲惶出拽喇装顿钥募埔命珊清更黄囚蝉钾挂渭腊詹无娥洗季百刹尝伊挞息譬垂豢滁殴淳笔涅坡阀澈铀猾亩嗜悄诀冗碰铺蠢乡镁盾螟下绣占皋妆序极舒斋疡ZigbeeWirelessSensorNetworkinEnvironmentalMonitoringApplicationsI.ZIGBEETECHNOLOGYZigbeeisawirelessstandardbasedonIEEE802.15.4thatwasdevelopedtoaddresstheuniqueneedsofmostwirelesssensingandcontrolapplications.Technologyislowcost,lowpower,alowdatarate,highlyreliable,highlysecurewirelessnetworkingprotocoltargetedtowardsautomationandremotecontrolapplications.It’sdepictstwokeyperformancecharacteristics–wirelessradiorangeanddatatransmissionrateofthewirelessspectrum.ComparingtootherwirelessnetworkingprotocolssuchasBluetooth,Wi-Fi,UWBandsoon,showsexcellenttransmissionabilityinlowertransmissionrateandhighlycapacityofnetwork.A.ZigbeeFrameworkFrameworkismadeupofasetofblockscalledlayers.Eachlayerperformsaspecificsetofservicesforthelayerabove.AsshowninFig.1.TheIEEE802.15.4standarddefinesthetwolowerlayers:thephysical(PHY)layerandthemediumaccesscontrol(MAC)layer.TheAlliancebuildsonthisfoundationbyprovidingthenetworkandsecuritylayerandtheframeworkfortheapplicationlayer.Fig.1FrameworkTheIEEE802.15.4hastwoPHYlayersthatoperateintwoseparatefrequencyranges:868/915MHzand2.4GHz.Moreover,MACsub-layercontrolsaccesstotheradiochannelusingaCSMA-CAmechanism.Itsresponsibilitiesmayalsoincludetransmittingbeaconframes,synchronization,andprovidingareliabletransmissionmechanism.B.Zigbee’sTopologyThenetworklayersupportsstar,tree,andmeshtopologies,asshowninFig.2.Inastartopology,thenetworkiscontrolledbyonesingledevicecalledcoordinator.Thecoordinatorisresponsibleforinitiatingandmaintainingthedevicesonthenetwork.Allotherdevices,knownasenddevices,directlycommunicatewiththecoordinator.Inmeshandtreetopologies,thecoordinatorisresponsibleforstartingthenetworkandforchoosingcertainkeynetworkparameters,butthenetworkmaybeextendedthroughtheuseofrouters.Intreenetworks,routersmovedataandcontrolmessagesthroughthenetworkusingahierarchicalroutingstrategy.Meshnetworksallowfullpeer-to-peercommunication.Fig.2MeshtopologiesFig.3isanetworkmodel,itshowsthatsupportsbothsingle-hopstartopologyconstructedwithonecoordinatorinthecenterandtheenddevices,andmeshtopology.Inthenetwork,theintelligentnodesarecomposedbyFullFunctionDevice(FFD)andReducedFunctionDevice(RFD).OnlytheFFNdefinesthefullfunctionalityandcanbecomeanetworkcoordinator.Coordinatormanagesthenetwork,itistosaythatcoordinatorcanstartanetworkandallowotherdevicestojoinorleaveit.Moreover,itcanprovidebindingandaddress-tableservices,andsavemessagesuntiltheycanbedelivered.Fig.3ZigbeenetworkmodelII.THEGREENHOUSEENVIRONMENTALMONITORINGSYSTEMDESIGNTraditionalagricultureonlyusemachineryandequipmentwhichisolatingandnocommunicatingability.Andfarmershavetomonitorcrops’growthbythemselves.Evenifsomepeopleuseelectricaldevices,butmostofthemwererestrictedtosimplecommunicationbetweencontrolcomputerandenddeviceslikesensorsinsteadofwireconnection,whichcouldn’tbestrictlydefinedaswirelesssensornetwork.Therefore,bythroughusingsensornetworksand,agriculturecouldbecomemoreautomation,morenetworkingandsmarter.Inthisproject,weshoulddeployfivekindsofsensorsinthegreenhousebasement.Bythroughthesedeployedsensors,theparameterssuchastemperatureinthegreenhouse,soiltemperature,dewpoint,humidityandlightintensitycanbedetectedrealtime.Itiskeytocollectdifferentparametersfromallkindsofsensors.Andinthegreenhouse,monitoringthevegetablesgrowingconditionsisthetopissue.Therefore,longerbatterylifeandlowerdatarateandlesscomplexityareveryimportant.Fromtheintroductionaboutabove,weknowthatmeettherequirementsforreliability,security,lowcostsandlowpower.A.SystemOverviewTheoverviewofGreenhouseenvironmentalmonitoringsystem,whichismadeupbyonesinknode(coordinator),manysensornodes,workstationanddatabase.Motenodeandsensornodetogethercomposedofeachcollectingnode.Whensensorscollectparametersrealtime,suchastemperatureinthegreenhouse,soiltemperature,dewpoint,humidityandlightintensity,thesedatawillbeofferedtoA/Dconverter,thenbythroughquantizingandencodingbecomethedigitalsignalthatisabletotransmitbywirelesssensorcommunicatingnode.Eachwirelesssensorcommunicatingnodehasabilityoftransmitting,receivingfunction.InthisWSN