Optimal beam radius for LED-based indoor positioning algorithm

Indoor positioning systems have the potential to replicate the success of outdoor positioning systems, but owing to the expensive and less accurate technology currently available for indoor positioning, they have not been able to take-off. LED-based Visible Light Communication (VLC) systems can solve this problem, but owing to complex algorithms and unoptimized parameter values the desired accuracy has not yet been achieved. This research addresses the problem of overlapping light radiation regions, which leads to lower accuracy in a VLC system, and proposes an algorithm to accurately determine the position of a device with respect to pre-positioned LEDs when it is receiving signal from multiple transmitting LEDs. To check the accuracy of this Optimal Beam Radius Indoor Positioning (OBRIP) algorithm numerous possible positions of a device uniformly distributed in a room with an indoor positioning system have been simulated to calculate the error in position estimation. Also, from the simulations, optimal values for beam radius, for a given number of LEDs in an array, separation between adjacent LEDs in an array for different room shapes has been calculated.