The optical illumination channel

Abstract

The optical illumination channel is defined as a communication channel associated with a lighting source whose primary functionality is to provide illumination. A description of this channel and the associated noise sources including thermal noise from the receiver electronics, ambient light noise from other light sources and signal dependent noise due to the stochastic nature of the optical signal is provided. We show that under a square root transform of the received signal and by proper signaling the channel converts into a unitary channel of the same form as the wireless radio additive white Gaussian noise (AWGN) channel with peak and average power constraints. Therefore this transform converts the optical illumination channel into a well understood format. The optimum detector is investigated. The proposed square root channel is compared with other common optical channels, in terms of power, and path losses where its simplicity is highlighted. The capacity as a function of the average illumination level of such a channel is calculated and investigated. Finally real scenarios are described where the applicability of the model is shown clearly.