Research On Indoor 3D Positioning Technology Based On The Fusion Of Bluetooth And Barometer

With the rapid development of information technology,people's lives are undergoing tremendous changes,and people's demand for location-based services is becoming more and more urgent,especially for indoor location services.In outdoor positioning system,BDS system and GPS system are limited by the indoor complex environmental conditions,and the accuracy drops sharply or even fails,so it is difficult to play a role in indoor positioning.while indoor two-dimensional positioning technology lacks elevation information,and it is difficult to meet people's needs for indoor location services.3D positioning technology generally has the problem that the hardware cost is relatively high when the accuracy is high and it is difficult to be widely promoted.When the hardware cost is low,the positioning accuracy is greatly reduced and it is difficult to meet the needs of location services.Therefore,it is of great significance to study high-precision and low-cost indoor three-dimensional positioning technology.Bluetooth technology is widely used in indoor positioning because of its advantages of low power consumption,low cost,easy deployment and so on.Therefore,this paper proposes an indoor 3D positioning scheme and algorithm based on the fusion of low power consumption Bluetooth and barometer to achieve high-precision and low-cost Indoor 3D positioning.The specific research work of this paper is as follows:First,by reading a large number of references,a detailed introduction to the positioning methods and positioning principles of various mainstream indoor positioning technologies and a comprehensive comparison of the advantages and disadvantages of various positioning technologies,and finally from the hardware cost and positioning accuracy of the positioning design.Based on comprehensive considerations,an indoor three-dimensional positioning solution integrating Bluetooth and barometer was selected for research.Secondly,in view of the complex hardware and high cost of indoor 3D positioning,in the traditional quadrilateral measurement method,the Bluetooth 3D positioning technology method is strongly dependent on the Bluetooth signal,the Bluetooth signal is very susceptible to non-line-of-sight interference or multi-path loss,resulting in poor positioning accuracy.For the problem of low accuracy,a three-dimensional Bluetooth positioning algorithm based on barometer height measurement assisted elevation measurement is proposed.The barometer measures the elevation value,reduces the Bluetooth three-dimensional positioning,and calculates the positioning coordinates on the two-dimensional plane through the improved weighted centroid method and then performs three-dimensional The coordinates are initially fused,and the initial coordinates of the fused positioning are corrected by the BP neural network optimized based on genetic algorithm to improve the accuracy of three-dimensional positioning.Finally,according to the indoor 3D positioning scheme integrated with Bluetooth and barometer,the STM32 core board,Bluetooth module and barometer module are used to build an indoor 3D positioning data acquisition platform,write STM32 data acquisition programs;and complete field selection of experimental scenes for planning,Bluetooth iBeacon Reference node deployment,design experiments to collect Bluetooth and barometer data in real scenes;and then the positioning algorithm is simulated through MATLAB 2016.b to analyze and verify the feasibility and effectiveness of the three-dimensional positioning algorithm proposed in this paper.Through the experimental verification of the Bluetooth and barometer data collected in the actual scene,it shows that the average positioning accuracy of the fusion positioning scheme and positioning algorithm in this article reaches 1.41 meters,which reduces the dependence on Bluetooth signals compared to pure Bluetooth three-dimensional positioning.The accuracy has been significantly improved.The three-dimensional positioning scheme proposed in this article has achieved high positioning accuracy on the basis of lower hardware costs,and has high practical value for engineering practice.