Research And Design Indoor Positioning System Based On IBeacon And PDR

With the advent of the intelligent Internet of Things era,there is a growing demand for location-based services(LBS).Positioning navigation as the most critical part will face many new challenges,although positioning navigation technology is quite mature in outdoor environment,there are many limitations to the positioning technology for indoor environment,which makes it difficult to meet the needs of pedestrians indoors in terms of accuracy,stability and real-time.Therefore,indoor positioning technology has gradually become one of the research hotspots in location-based services,and has broad application prospects.The iBeacon positioning technology based on Bluetooth communication protocol has the advantages of wide positioning range,suitable for long time positioning w ithout accumulating error,but in the process of positioning,due to the existence of environmental interference and other factors make RSSI signal fluctuations,which often causes the positioning result to become extremely unstable.Pedestrian Dead Reckoning(PDR)algorithm is not affected by the external environment,can obtain relatively good positioning accuracy under the condition of short time positioning,but with the increasing time,the positioning error accumulates continuously.This paper makes full use of the positioning advantages of iBeacon positioning and PDR positioning,and proposes a fusion indoor positioning algorithm,and designs and develops the system.The main work is as follows:(1)Firstly,the technical principle of iBeacon positioning is analyzed,The RSSI ranging model is analyzed and the actual ranging model of the positioning envir onment is fitted by experiments,the existing iBeacon positioning algorithm is analyzed,aiming at the deficiency of the current algorithm,this paper proposes the iBeacon location algorithm and specific implementation scheme.(2)Several key steps in the PDR positioning algorithm are studied,and the classic peak detection algorithm is improved for the gait detection part.The step estimation part mainly analyzes the three nonlinear estimation models experimentally,and selects the estimation model with less influence on the error.In order to reduce the effect of jitter during walking,the measured heading angle is divided into intervals,and the median value is taken as the heading angle.(3)In view of the complementary advantages,this paper proposes an indoor positioning algorithm based on iBeacon positioning and PDR positioning fusion.This algorithm can use PDR positioning to reduce the large positioning error caused by RSSI signal fluctuation in iBeacon positioning,and can also use iBeacon positioning to reduce the error caused by time accumulation in PDR positioning.This fusion strategy can solve the defects of single indoor positioning technology,realize simple,and can effectively improve the accuracy of indoor positioning.(4)Finally,the positioning client and the positioning background server are respectively implemented under the Android platform and Spring+MySQL+JAVA+Netty framework.Through the comparative analysis of experimental data,compared with the single positioning technology,the fusion positioning algorithm in this paper has a relative improvement in positioning accuracy.