A Survey on Advances and Future Prospects of Modulation Schemes for VLC

The reported performance characteristics of the Visible Light Communication (VLC) system make it an appropriate candidate for future optical wireless technology. The RF spectrum has become very congested because of the growth and the need for RF spectrum in wireless communication and day-to-day life; and costly due to the need to license. The VLC spectrum is license-free and can support high data rate systems. Further, modulation schemes for VLC which appeared in previous research are the direct modulation schemes that introduce unavoidable demerits as flickering and dimming. There have been many advances in opted modulation schemes in IEEE 802.15.7. This article presents a survey that summarizes a few modulation schemes with enhanced performance characteristics for VLC. It also proposes a new modulation scheme using an external modulator which could be considered as a future option for the VLC system.