CeilingCast: Energy efficient and location-bound broadcast through LED-camera communication

Abstract

Although Visible Light Communication (VLC) is gaining increasing attentions in research, developing a practical VLC system to harness its immediate benefits using Commercial Off-The-Shelf (COTS) devices is still an open issue. To this end, we develop and deploy CeilingCast as a location-bound wireless broadcast system using COTS LEDs as transmitters and smartphone cameras as receivers. CeilingCast innovates in its effective coding and efficient decoding schemes, so that it can be fully hosted in a smartphone and is feasible for all possible indoor environments. Moreover, we analyze the impact of various parameters on the performance of CeilingCast, in order to derive a model for such VLC systems enabled by COTS devices and hence provide general guidance for future VLC deployments in larger scales. Finally, we conduct extensive field experiments to validate the effectiveness of our LED-camera VLC model, as well as to demonstrate the promising performance of CeilingCast under various parameters.