Experimental Comparisons of Optical OFDM Approaches in Visible Light Communications

This paper presents an experimental comparison of optical orthogonal frequency division multiplexing (OFDM) approaches in visible light communications (VLC). We demonstrate that OFDM schemes with asymmetric signals suffer from baseline wander in practical transmission experiments, which degrades the overall bit-rate performance. Several schemes that combat this effect are reported and the performances of these schemes are measured. However, it is demonstrated that a DCO-OFDM scheme achieves higher bit-rate at target BER in a VLC system that is bandwidth-limited.