A 3D indoor positioning system based on common visible LEDs

We propose a realistic 3D positioning system for indoor navigation that exploits visible Light EmittingDiodes (LEDs), placed on the ceiling. A unique frequency tone is assigned to each lamp and modulatesits intensity in periodic time slots. The Time Difference of Arrival (TDOA) is measured without theneed of a synchronization system between the sources and the receiver, then it is used to accuratelyestimate the receiver position. We first describe the theoretical approach, then propose the modeland characterize the possible sources of noise. Finally, we demonstrate the proof-of-concept of theproposed system by simulation of lightwave propagation. Namely, we assess its performance by usingMontecarlo simulations in a common room and estimate the impact of the different implementationparameters on the accuracy of the proposed solution. We find that, in realistic conditions, thetechnique allows for centimeter precision. Pushing the device requirements, the precision can befurther increased to a sub-centimeter accuracy.