Energy saver VLC using off-the-shelf devices: an experimental study

Abstract

A forecast that internet-of-things (IoT) devices will be humungous, more than a billion, and the numbers will increase rapidly in the coming years. The exchange of information among devices is getting more massive day by day, putting a strain on current technologies and leading to the scarcity of radio-frequency (RF) spectrum. IoT foresees the extensive use of visible light communication (VLC) technology. The implementation of a VLC link on communication interfaces of existing computers and smartphones saves energy by using energy efficient LEDs and existing infrastructure. Transferring data between two laptops or two mobiles using visible light is in its infancy, and extensive research is going on to bring Light-Fidelity (Li-Fi) in every day IoT. Universal asynchronous receiver/transmitter (UART) is a global standard used for computer communication. Integrating visible light communication between two laptops via UART is a useful application for IoT devices while in case of mobile the existence of flashlight in the back and light detector in the front is made use for the communication. The work aims to perform point-to-point communication using visible light between off-the-shelf devices such as two laptops and two mobiles. A reliable working prototype of the system having transmitter and receiver is designed and built for both the cases. Real-time transfer of data such as alphabets, words, text and image are done via a graphical user interface (GUI) in laptop and app in mobile. Letter error rate analysis is also performed with respect to various parameters.