Location-basedservices,suchastargetedadvertisement,geo-socialnetworkingandemergencyservices,arebecomingincreasinglypopularformobileapplications.WhileGPSprovidesaccurateoutdoorlocations,accurateindoorlocalizationschemesstillrequireeitheradditionalinfrastructuresupport(e.g.,rangingdevices)orextensivetrainingbeforesystemdeployment(e.g.,WiFisignalfingerprinting).Inordertohelpexistinglocalizationsystemstoovercometheirlimitationsortofurtheri
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