Handover in VLC systems with cooperating mobile devices

Visible Light Communications (VLC) is emerging as viable means to overcome the crowded radio spectrum for highly-localized communications systems. With such an approach, luminaires can be adopted for supporting data communication in addition to illumination in what we call Cellular Lighting. However, in these systems, the directionality of light as the communication medium introduces new challenges in sustaining network connectivity especially under mobility scenarios. In this paper we investigate mobility in VLC devices and propose an approach to managing handover adopted from wireless cellular systems, but with very small cells and directional characteristic. Moreover, this technique provides the coordination and cooperation among VLC devices to achieve seamless connectivity in two different indoor scenarios consisting of overlapping (uniform lighting) and non-overlapping (spotlighting) cases. Results indicate how different design decisions in supporting luminaire placement achieve full coverage at varying data rates.