Design And Implementation Of An Indoor Ranging System Based On Low Energy Bluetooth

With the rapid development of information technology,Location based service(LBS)has been widely researched and developed.This is based on user's distance and location information.In the outdoor environment,GPS technology as one of the most successful and the most widely used ranging-positioning technologies can meet most of the needs.But in the indoor environment,GPS technology does not work very well as the constructions and walls block the GPS signals.Wireless Bluetooth sensor module based on Bluetooth low energy has become a research focus in the area of indoor distance measuring and positioning with the advantages of low power,low cost and easy deployment.This thesis proposed a technical solution of indoor distance measurement based on Bluetooth low energy by using BLE sensor and Android client to measure the indoor distance.First of all,the existing key technologies of indoor ranging were researched and analyzed,and the RSSI method was chosen for the research in this paper.Then the key factors that affect the ranging precision method based on the RSSI were analyzed,and on this basis,the existing RSSI filtering algorithms and the advantages of RSSI data in the indoor environment were analyzed in detail,then a Gaussian-hierarchical clustering based RSSI filtering algorithm was proposed.This algorithm can remove the abnormal RSSI data effectively combining the advantages of Gaussian filtering algorithm and the hierarchical clustering algorithm.The performance simulation of the algorithm proposed above showed that this algorithm can improve the stability and smoothness of the RSSI data.In the third part of this paper,the overall system architecture was brought up on the basis of the demand analysis of this system.Meanwhile,the algorithm proposed above was applied into the system,and then the thesis analyzed and stated the design and implementation of low energy Bluetooth RF module and the Android ranging client.In the end of the paper,tests of the indoor ranging system based on low energy Bluetooth were carried out,mainly including the test of low energy Bluetooth RF module,the test of Android ranging client and the performance test of the whole system.The test results showed that the indoor ranging system based on low energy Bluetooth can control the error in 2 meters with both good practicality and feasibility,and the various functions implemented in this system are able to meet the expected design indexes.