Design and implementation of visible light communication system using pulse width modulation

Visible Light Communication (VLC) is a relatively new technology which could potentially be complementary to the existing radio frequency communication system. VLC allows lamp or other kinds of light source not only used as illumination, but also as a data transmission at the same time. Single carrier modulation technique is suitable to be applied on VLC that does not require high-speed data transfer. In this paper, we proposed a visible light communication scheme using pulse width modulation (PWM) technique in transmitting data for running text application. To evaluate the PWM accuracy, experiments were conducted based on different parameters such as PWM frequency, transmitter-receiver distance, and the receiver's angle of view. Furthermore, we also measured the point-to-point communication system performance which resulted in 920 bps data transfer rate and 10-4 bit error rate (BER) without affecting the lighting function.