Amplitude modulation by superposition of independent light sources

Visible light communication (VLC) is a promising alternative to radio waves, when high data rates are required over short distances. Using lighting equipment for communication offers very high receive power values without consuming additional energy than already required for illuminating the environment. The bandwidth restriction of the employed light-emitting diode (LED) light sources is one limiting factor to exploiting the channels potential capacity. In this paper, we propose spatially distributed modulation schemes to increase the data rate by switching the LEDs of the lighting equipment individually. Towards this goal, three different techniques for superposition of independent light sources are compared.