Abstract: This paper set about to elucidate the various modulation techniques for Light-Fidelity (LiFi). Digital modulation techniques generally used for LiFi are summarised, and some special issues and requirements are discussed. In principle, LiFi also relies on electromagnetic radiation for information transmission. Therefore, typically used modulation techniques in RF communication can also be applied to LiFi with necessary modifications. Moreover, due to the use of visible light for wireless communication, LiFi also provides a number of unique and specific modulation formats.
Keywords: Li-Fi, VLC, LED, OOK, PPM, OFDM, CSK.