Relay-assisted OFDM-based visible light communications over multipath channels

In this paper, we investigate the performance of relay-assisted visible light communication (VLC) system over multipath channels. We consider an indoor environment where the ceiling light serves as the information source and a desk light helps the source forward the information to the destination. The VLC system is built on orthogonal frequency division multiplexing (OFDM) with either amplify-and-forward or decode-and-forward relaying. A realistic channel impulse response of the indoor environment generated through ray tracing is used. Through simulations, we present the bit error rate performance of OFDM-based relay-assisted VLC system over indoor multipath channels and quantify the performance degradation with respect to idealistic single tap channels. We further discuss the impact of imperfect channel estimation on the performance.