Research On Visible Light Positioning Method Based On Received Signal Strength Indicator

With the widest field of application in visible light positioning technique,received signal strength indicator(RSSI)based visible light positioning method is proud of its advantages as low construction cost,low energy cost,easy to construct,good portability,high speed of response,etc.In spite of this,it is also confused by the problem of background light interference,which is the most important restraining factor that makes 1-centimeter positioning accuracy a distant destination.Obviously,the RSSI visible light positioning method that presumptively has an ideally high accuracy could be the most competitive indoor positioning method,in case that noise interference problem has been solved.Focusing on RSSI visible light positioning method,and aiming at high accuracy,this dissertation finds its way from both receiving and transmitting terminal.In receiving terminal,we base our work on reducing the noise interference in received signals to effectively decrease stochastic error.By utilizing wavelet analysis to significantly reduce the noise mixed with received signal and adopting correlation method to extract the source signal from the reduced noise in receiving terminal,the positioning accuracy of RSSI method is evidently improved.By comparison of the results in several signal-to-noise Ratio(SNR)condition via simulation,it is proved that the RSSI based visible light positioning system with this processing algorithm has the error bound stabilizing in 1cm and is insensitive with noise.In transmitting terminal,we base our work on improving the irradiation property of the signal resources to decrease systematic error.A linear attenuated illuminating model is proposed to decrease the systematic error and eliminate the fade zones of the positioning system,which is proved a competent method by simulation.By fitting a free-form surface optical lens to the signal source,we complete the design of this linear attenuated illuminating lighting,the radiation characteristic of which is proved well by beam tracing.After the work of this dissertation,we have made some achievement as follow: The positioning accuracy of RSSI based visible light communication method has reached millimeter order by improving processing algorithm;The problem of fade zones of the positioning system has been solved by linear attenuated illuminating resource designing...