The Research Of Indoor Position Algorithm Based On Bluetooth Technology

In recent years,a variety of new applications of wisdom emerge in endlessly with the rapid development of the Internet of Things and the accelerated pace of social life.Moreover,the demands of indoor positioning applications based on LBS(Location-Based Service)are becoming increasingly intense,such as the promotion of discount information and indoor navigation in the shopping malls,the intelligently searching for parking space in the parking lot and so on,all of which are on the basis of indoor positioning system.The indoor positioning technology based on Bluetooth Beacon boasts the advantages of ultra-low power consumption,superior marketing,higher positioning accuracy as well as lower cost,which make it stand out among various positioning technologies.Therefore,it is very meaningful to carry out the research of indoor positioning algorithm based on Bluetooth Beacon.In this paper,we have intensively studied the indoor positioning technology based on Bluetooth technology:(1)Starting from the background and significance of indoor position,this paper elaborately analysed the domestic and foreign research status in this line based on Bluetooth technology and gave the summarize of its future trends.(2)This paper also analysed several kinds of indoor positioning program and algorithms commonly used at present and compared the advantages and disadvantages between them.Then it gave a detailed description of the superiority of indoor position based on Bluetooth technology and also introduced Beacon's technical characteristics,workflow and the deployments in different indoor situations.(3)Given those problems caused by factors,including the unstable transmission of RSSI(Received Signal Strength Indication)in indoor environment,the inaccurate match between propagation path loss model of the wireless channel and the indoor environmental features,and also the declining positioning accuracy in actual practice owing to some emergent disturbs.The corresponding improvement solutions had been put forward in every part of the fingerprint location algorithm.Besides,this paper also provided the algorithm's workflow and corresponding calculation formula in details.The improved algorithm based on fingerprint database was divided into three stages.Aiming to solve the inherent deviation of the Beacon in the first stage and the environmental deviation caused by the actual environment of Beacon,the paper put forward the RSSI correction.In the second stage,it raised the method to obtain environmental factors by spot training,which helped improve the propagation path loss model,making the distance value transformed by RSSI more in line compared with the actual value.In the third stage,a KNN(K-Nearest Neighbor)algorithm based on spatial filter was proposed,which helped avoid the cases that KNN's large calculation and the sharp fluctuations of Beacon's signal,incurred by the sudden changes of indoor environment in actual positioning,cause the positioning deviation.Therefore the positioning accuracy is relatively improved.(4)The last part of this paper was to simulate and verify the improved algorithm,and simulteniously to accomplish the elderly monitoring system based on indoor position.The system made the Andriod client which has many powerful functions such as realizing the map replacement,setting location,adding base stations,collecting RSSI fingerprint database,setting special regions,replacing special areas,alarming the elderly relatives by SMS(Short Message Service),displaying personal health information and real-time location,and so on.This system not only allowed users to find their own location information easily,but also made the guardianship of the elderly more rational and humane for communities and families.