Research On Indoor Positioning Algorithm Based On Visible Light

With the advancement of science and technology in modern society and the rapid development of wireless communication technology,intelligent mobile terminals are becoming more and more popular,and location-based services play an increasingly important role in people’s daily life.The development of positioning technology and the demand for application services have become more frequent in daily life.Since visible light communication can support lighting and communication at the same time,it has been widely used in many applications,and the indoor positioning technology based on visible light communication is a promising indoor positioning technology.At present,there have been many achievements in the research of visible light indoor positioning algorithm at home and abroad,but each has its own shortcomings.The research of visible light indoor positioning needs to comprehensively consider many factors such as cost,accuracy,robustness,and complexity.Aiming at the problems and difficulties of the above-mentioned visible light indoor positioning algorithm,this paper conducts a survey,summary and in-depth research on relevant literature.The main contents are as follows:Firstly,the visible light communication channel model and some positioning technologies are introduced,various algorithms are classified,and the principles of various algorithms are introduced with examples,including fingerprint method,nearest neighbor method,geometric method and image sensor method,etc.The advantages and disadvantages of various algorithms are summarized and compared.Secondly,in view of the problem that the existing AOA system uses the optical receiver to detect the optical power,but the parameters of the receiver may not be optimized to reduce the positioning error,a visible light indoor positioning based on the best AOA estimator is proposed.algorithm.The PD array at the receiving end is optimized,and a low-complexity algorithm to estimate AOA is described in detail by solving the linear equation system,and the relationship between the estimated incident vector,the actual incident vector,and the estimated noise is obtained,and then The optimal optical omnidirectional angle of arrival estimator is obtained.Then,based on the best angle of arrival estimator as the receiver,a novel 3D visible light indoor positioning algorithm is proposed,and MATLAB simulation analysis is carried out.In addition,when the number of LEDs is more than two,two screening methods are proposed for the algorithm to improve the positioning accuracy.The simulation experiment results show that these two screening methods can improve the positioning accuracy.In addition,if the screening method is performed multiple times,only two LEDs can be used to complete the positioning each time the target is positioned.The proposed algorithm can achieve centimeter-level accuracy,which will provide some inspiration for the design of AOA systems.Finally,a new VLP system is proposed for the problem of inter-cell interference with multiple LEDs and some specific scenarios where the number of LEDs is limited.By using a single LED as the transmitter,the receiver consists of a PD fixed on a rotatable platform.By rotating the receiver several times,the incidence vector is estimated and its probability density is given.In addition,the time when rotated twice is also given.The algorithm to realize twodimensional positioning,the algorithm constructs the equation system through the ratio of the received signal strength to realize the positioning,and quantitatively analyzes the positioning error expression.In the simulation experiment,the influence of the tilt angle and the difference of two rotation angles on the positioning accuracy is analyzed,and the optimal tilt angle and rotation angle difference of the system are given.The experimental results show that the positioning system can achieve centimeter-level accuracy when the appropriate tilt angle and rotation angle difference are selected.