Optimization Of Visible Light Indoor Positioning System Based On Performance Analysis

In modern society,the location-aware service of indoor scenes has become an indispensable part of people's daily life and work.Visible light positioning based on Received Signal Strength(RSS)technology is getting more and more attention due to its advantages of low cost,high precision,high safety and low energy consumption.In the existing RSS-based indoor positioning system for visible light,the influence of the light source selection method and the light source layout on the positioning error in the positioning algorithm is not considered.In response to the problems,this thesis uses a performance analysis method based on Cramér–Rao lower bound(CRLB)to optimize the light source layout and positioning algorithm in the positioning system to improve positioning accuracy.CRLB can evaluate the positioning performance of the positioning system.Geometric Dilution Of Precision(GDOP)can find some factors that can affect the positioning performance.Using the CRLB method to quantitatively analyze the local density of light sources,the number of light sources and the arrangement of light sources on the positioning performance in the positioning system.Based on the analysis results,an optimized plan for the layout of light sources with an equilateral triangle distribution of 2m spacing is designed.The influence of light source selection on positioning performance was analyzed by CRLB,and a positioning algorithm with adaptive light source selection was designed and implemented to reduce the positioning error of the system.In this thesis,a simulation environment and a real environment of a 6×6×2.98m3 visible light indoor positioning system are built for positioning testing.In the simulation positioning system of 9 LED lights and equilateral triangle distribution,the simulation error of the design scheme in this paper is 4cm,which is 61%lower than that of the indoor positioning system before optimization.In the same real environment,the average error of the design scheme in this paper is 11.2cm,which is 39% lower than the indoor positioning system before optimization.In this thesis,the visible light indoor positioning system based on RSS after the optimization of light source layout and positioning algorithm has better positioning accuracy,reaching the design index.