On the Performance of Single- and Multi-carrier Modulation Schemes for Indoor Visible Light Communication Systems

TL;DR

This paper compares single- and multi-carrier modulation schemes for indoor visible light communication, highlighting SCFDE's advantages over OFDM and OOK, and examining LED biasing and coding techniques to improve performance.

Contribution

It provides a comprehensive analysis of modulation schemes for VLC, introducing SCFDE as a superior alternative and exploring LED biasing and coding for enhanced performance.

Findings

SCFDE outperforms OFDM and OOK in indoor VLC.

SCFDE does not suffer from high PAPR unlike OFDM.

Optimal LED biasing significantly improves OFDM performance.

Abstract

In this paper, we investigate and compare the performance of single- and multi-carrier modulation schemes for indoor visible light communication (VLC). Particularly, the performances of single carrier frequency domain equalization (SCFDE), orthogonal frequency division multiplexing (OFDM) and on-off keying (OOK) with minimum mean square error equalization (MMSE) are analyzed in order to mitigate the effect of multipath distortion of the indoor optical channel where nonlinearity distortion of light emitting diode (LED) transfer function is taken into account. Our results indicate that SCFDE system, in contrast to OFDM system, does not suffer from high peak to average power ratio (PAPR) and can outperform OFDM and OOK systems. We further investigate the impact of LED bias point on the performance of OFDM systems and show that biasing LED with the optimum value can significantly enhance the performance of the system. Bit-interleaved coded modulation (BICM) is also considered for OFDM and SCFDE systems to further compensate signal degradation due to inter-symbol interference (ISI) and LED nonlinearity.