Visible Light Communications localization using TDOA-based coherent heterodyne detection

Visible Light Communications (VLC) can be achieved with the use of Light Emitting Diodes (LED). It can be used for indoor positioning of people or smart devices. Previous work considers coherent detection, which uses the amplitude (in-phase (I) component) and phase (quadrature (Q) component) of the optical power signal and achieves an accuracy of less than 1mm, but they did not consider noise. In our work, we utilize a mathematical model for photodetection with Gaussian noise. We employ 3 stages of estimation algorithms on the measurements to minimize the noise affects. The performance is evaluated using MATLAB and we achieve an accuracy of less than 2cm in the room space of 5m × 5m × 3m.