Indoor Position Tracking Using Visible Light

The demand for a highly accurate indoor positioning system is rapidly increasing. In the last few years, several positioning systems based on visible light communications that achieve good positioning accuracy have been proposed. However, these systems are based on assumptions such as complete knowledge of the height of the receiver, exact alignment of the transmitter and receiver normals to the normal of the ceiling. Recently, authors have proposed a positioning system without these assumptions. The system, however, does not support user mobility because it requires a user to vary the receiver orientation at a fixed location. In order to support user mobility, we propose a novel positioning system in this work using multiple optical receivers. The remarkable features of the proposed system are as follows: (a) the receiver can be mobile; (b) the positioning is done within 6 milliseconds in our experiment; (c) the heights of the transmitters need not be the same; (d) the receiver´s height need not be known; and (e) the receiver´s normal need not be aligned with those of the transmitters. We have tested our positioning system in a mobile scenario and results show that mean position errors of less than 0.06m is achievable.