This paper presents a Visible Light Communication (VLC) system architecture suitable for outdoor applications. VLC usages in outdoor scenarios are facing new opportunities raised by the increasing trends on the usage of LEDs. Traffic light signals and public illumination systems are two application examples, where VLC can show its merits. These scenarios pose several challenges due to the fact that it is difficult to control environmental conditions. Thus, VLC systems able to operate under these conditions need to employ robust modulation schemes. This paper proposes the usage of direct sequence spread spectrum to combat noise and interference. The implemented prototype demonstrates that it is feasible to achieve more than 40m communication range for low data rate applications even in the presence of significant optical noise levels.
N. Lourenco, Terra, D., Dr. Navin Kumar, Alves, L. Nero, and Aguiar, R. L., “Visible Light Communication System for outdoor applications”, in 2012 8th International Symposium on Communication Systems, Networks Digital Signal Processing (CSNDSP), Poznan, Poland, 2012.