Burst Error Correction Code for Visible Light Communication

Visible Light Communication (VLC) is a technology that uses visible light as the carrier for signal transmission. Light Emitting Diodes (LEDs) have been widely used in our life, such as billboards, traffic lights. So the VLC that uses LEDs at visible wavelength, which are modulated at a very high speed, to carry the information. The modulated light is received by photodiodes and translate into electric signals. VLC has a potential to combine existing LED systems. For the VLC system based on LED lighting apparatus, the signals are usually broadcasted. In such a system when the light is accidently block by hands or any flying objects, the receiver may lost data. As a result, a system without additional feedback but can fix burst error is important to improve the performance of this kind of VLC. In this thesis, a lamp type visible light communication loopback testing system was built with commercially available component. Include LED driving circuit, photodiode, comparator circuit and FT232 serial to USB module. The software in the host computer for encoding and decoding the data is written in C# and control the data transmission and receiving through the serial port. The key point of this thesis is combining interleaved Hamming code and timestamps that count exact number of lost data to fix the burst error up to 1 second. When the data is interrupted accidently by hands or other flying objects, it can fix it by the software. In this way, the potential of VLC can be improved greatly.