A Survey of Modulation Schemes in Visible Light Communications

As the number of internet users continues to increase, the demand for more wireless frequency spectrum has grown significantly over the years. Given the limitations in Wireless Fidelity (WiFi) networks, it becomes evident that the current frequency allocation schemes cannot meet the needs of increasing higher data rate devices. Visible Light Communication (VLC) has emerged as one of the promising technologies to address the spectrum crunch and other anomalies associated with WiFi networks. VLC provide high-speed, secure and reliable data communication using Light Emitting Diode (LED). This paper reviews the various modulation schemes suitable for VLC networks. Furthermore, performance analysis of these schemes in terms of normalized power requirement, Signal to Noise Ratio (SNR), spectral efficiency, dimming factor and Bit Error Rate (BER) are discussed. Finally, applications of VLC are presented.