Characteristic and Modeling of Human Body Motions for Body Area Network Applications

IntJWirelessInfNetworks(2012)19:219–228DOI10.1007/s10776-012-0176-2

CharacteristicandModelingofHumanBodyMotionsforBodyAreaNetworkApplications

RuijunFu YunxingYe KavehPahlavan

Received:13January2012/Accepted:14May2012/Publishedonline:6July2012ÓSpringerScience+BusinessMedia,LLC2012

AbstractManycurrentandfuturemedicaldevicesarewearableandhumanbodyisusedasacarrierforwirelesscommunication,whichimplieshumanbodytobeacrucialpartofthetransmissionmediuminbodyareanetworks(BANs).Inordertounderstandthepropagationcharac-teristicsaroundhumanbody,thestatisticalmodelisderivedforcommunicationlinksinthemedicalimplantcommunicationserviceband,industrialscienti cmedicalbandandultra-widebandbasedonthenarrowbandmea-surement.Thechannelmodelofdiffractingcomponentsaroundhumanbodyweredifferentfromonescenariotoanother.Moreover,secondorderstatistics,includinglevelcrossingrateandfadeduration,arepresentedforeachscenariotoevaluatethelinkqualityandoutageperfor-manceforon-bodytoon-bodyscenario.Usinganetworkanalyzer,Dopplerspreadspectruminfrequencydomainandcoherencetimeintimedomainfromtemporalvaria-tionsofhumanbodymovementsarealsoanalyzedfromdiverseperspectives.Additionally,theshapeofDopplerspreadspectrumis ttedtodescribetherelationshipofpowerandfrequency.Theproposedon-bodytoon-bodychannelmodelforhumanbodymotionscanbeusedtobetterdesignwirelessnetworkprotocolsforBANs.KeywordsBodyareanetworks(BANs)Á

PropagationchannelÁFirst-orderstatisticaldistributionÁLevelcrossingrateÁFadedurationÁDopplerspreadÁRMSDopplerspreadÁDopplerspreadspectrumÁCoherencetime

1Introduction

Rapidgrowthinlowpowerintegratedcircuitsandwirelesscommunicationhasmadethemedicaldetectionwithminiaturizedsensorscometrue.Bodyareanetwork,whichconnectsthesewirelessdevicestohumanbody,hasgainedconsiderablepopularityinmedicalcareapplications[4].Thesewearableandswallowablemedicalsensorscouldcontinuouslymonitorhealthparametersinrealtimeandsendtoacentraldevicesuchassmartphones.IEEE802.16.5TaskGroup6isof ciallyworkingonstandardi-zationofBANs,includingpropagationcharacteristicsandmediumaccesscontrolprotocolsformedicalimplantcommunicationservice(MICS)band,industrialscienti candmedical(ISM)band,wirelessmedicaltelemetryband(WMTB)andultra-wideband(UWB).Buttherearestillmanychallengesinbodyareanetworks(BANs),whichcallforincreasingmobility,highercapacityandlowerpowerconsumption.Inordertodesignbetterwirelessdevicesforhealthcareapplications,itissigni canttounderstandthepropagationcharacteristicsinBANs.Furthermore,under-standingtheperformanceofon-bodycommunicationlinksisalsoimportantindesigningandevaluatingmediumaccesscontrolprotocolsforspeci cscenariosde nedin[25].

Withwirelesssensorsplacedonaperson,thehumanbodymotionscouldbeaccuratelyrecognizedandremotelydetected.InBANs,temporalvariationsofchannelarerelatedtobodyconditions,bodymotions,antennaposi-tions,frequencybandsandsurroundingenvironment.Thegeneralcharacterizationofon-bodyfadingchannelsisrequiredtobeanalyzedthoroughlyinascenariobasedapproach[21].Amongallthein uencedfactorsmentionedabove,thehumanbodymotionisakeyfactorleadingtoagreatervariationofthecommunicationchannel.Thispaper

R.Fu(&)ÁY.YeÁK.Pahlavan

DepartmentofElectricalandComputerEngineering,WorcesterPolytechnicInstitute,Worcester,MA,UnitedStatese-mail:ruijunfu@gmail.com

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