EXPERIMENTAL INVESTIGATION OF VLC SYSTEMS WITH CAMERA RECEIVER

Abstract

Current fluorescent and incandescent lamps are being replaced by solid state Light Emitting Diodes (LEDs), which offers much higher energy efficiency and longer lifespan. Apart from that LEDs are able to switch on and off at rapid rates. Such capability has given a lift to new communication technology – Visible Light Communication (VLC). LED serves as a transmitter, by providing high throughput data transfer, while photodiode or optical camera are utilized as a receiver. This thesis experimentally investigates a VLC system that uses a camera receiver. We first analyze the system with simple On-Off Keying (OOK) technique and further propose an alternative technique – Pulse Amplitude Modulation (PAM), which increases the data rate and avoids visible flickering. Furthermore, this thesis investigates VLC exploiting rolling shutter mechanism of CMOS images sensors with OOK. The Bit Error Rate (BER) performance and some characteristics of systems are presented. Next, VLC utilizing rolling shutter mechanism with Color-Shift Keying (CSK) is developed. Such a system achieved substantially higher data rates compared to VLC exploiting rolling shutter mechanism with OOK.