Research Of Indoor Communication And Positioning System Based On LED Visible Light

At present,the traditional wireless communication technology has become more and more difficult to meet people's requirements because of its shortcomings such as the shortage of spectrum resources,limited use area and easy to be monitored.Therefore,a new wireless communication technology-LED visible light communication technology has gradually come into people's vision.Compared with the traditional radio frequency communication technology,the use of LED visible light for communication has many advantages,such as rich spectrum resources,unlimited use of sensitive areas,green security,high confidentiality and so on.It can effectively solve the disadvantages exposed by the traditional wireless communication technology.At present,the technology of visible light communication based on LED is developing rapidly,and it has become a very popular research topic in the field of wireless communication at home and abroad.It has bright application prospects and broad development space.In this paper,the characteristics of LED are introduced,the impulse response and DC gain of communication channel are analyzed,and the signal-to-noise ratio of channel is calculated.At the same time,the distribution model of illumination and light power is established through theoretical analysis and simulated with MATLAB.This paper designs an indoor communication system based on LED visible light.The system uses STM32F407 as the main control chip,builds the voltage stabilization circuit,driving circuit and other peripheral circuits,completes the signal modulation and demodulation process by software programming,and realizes the data communication between two computers through visible light.This paper also makes a detailed analysis of common indoor visible positioning algorithms,and proposes a RSS indoor visible hybrid positioning algorithm based on fingerprint data,which optimizes the parameters of LED radiation model.Compared with fingerprint database algorithm and RSS trilateral measurement algorithm,the positioning accuracy has been greatly improved.The paper also expands the indoor positioning function on the basis of the LED visible indoor communication system.The positioning system realizes the functions of signal filtering and data storage through software programming.The cost is low.The positioning error is generally less than 20 mm,which can meet the daily needs and has good engineering application value.