On the Interference Immunity of Visible Light Communication (VLC)

Visible Light Communication (VLC) relies on the dual use of existing light infrastructure for wirelessly send data. VLC is regarded as a "green", cost-effective and secure communication technology. Moreover, VLC has been always considered immune to Radio Frequency (RF) waves. The only type of interference that has always been included in the channel model is the optical interference. Nevertheless, all the interference components potentially impacting on the performance of the system should be integrated in the transmitting model in order to improve the performance of the communication system. In this paper, we investigate on the interference and immunity of the VLC systems in respect of frequencies spanning the spectrum up to 1 GHz. We provide a detailed evaluation of the immunity of a VLC system by the means of experiments realized in "controlled" environment, i.e. an anechoic chamber, by considering interference at different power levels. Results are very interesting, since at specific frequency values, the VL transmitted signal results too "interfered" and noisy to be correctly recovered. In order to evaluate the impact of this interference, we have estimated the Bit Error Rate (BER) for different index modulations of Pulse-Position Modulation (mPPM).