RSS And Hybrid Algorithm For Indoor Visible Light Localization

As people have incrersingly high demand of location-based services,wireless positioning technology has developed quickly.Due to its advantages that traditional wireless positioning methods can not be replaced,a new indoor positioning technology based on visible light communication(VLC)has been widely concerned and becomes a hot research field recently.The indoor visible light positioning technology can meet the last one meter of LBS,which plays an important role in economy,science research and military fields.Various indoor visible light positioning algorithms based on VLC are analyzed in this thesis,including the Received Signal Strength(RSS),Time Difference of Arrival(TDOA),Time of Arrival(TOA)and Angle of Arrival(AOA)etc.The fundalmental positioning principle of the various algorithms is given,especially RSS&TDOA hybrid positioning algorithm and a two phase hybrid RSS&AOA algorithm based on LED visible lights are thoroughly investigated.First,build the modeling for indoor visible light channel combined with practical application.Then,simulate the current various positioning algorithm in order to improve the performance of indoor positioning algorithm.Aimed at some limitations of current TDOA localization algorithm with disconvergence and affeceted by synchronization error easily,a hybrid RSS and TDOA positioning algorithm using white lighting LEDs is proposed in this paper.This algorithm that we proposed improved the current based-RSS fingerprint location algorithm,and reduced the finding time and calculation procedures.By utilizing a nonlinear programming algorithm with constraints,the position coordinates of the TDOA terminal can be obtained.It effectively solves the problem that conventional RSS or TDOA algorithm used in indoor noisy environments and verify the reliability of the hybrid positioning algorithm used for indoor positioning.For the problem of the received signal attenuation localization algorithm with low accuracy and poor stability,we proposed a two phase hybrid RSS and AOA positioning algorithm The coarse estimate position is obtained by a weighted centroid calculation based on the signal strength values.The fine phase use the azimuth and elevation observables to establish a fine estimate.This algorithm takes full advantage of the dual advantages of RSS and AOA.According to the use of two phase hybrid positioning methods,we can find the optimal location solution and achieve multiple LED precise positioning.