Experimental demonstration of LED-to-LED visible light communication between a traffic light and a vehicle headlamp

Visible light communication (VLC) technology using light-emitting diodes (LEDs) is currently being discussed to solve the problem of oversaturation in radio frequency (RF) bands. We conducted this study due to a lack of research on LED-to-LED VLC in the context of vehicle communication. One of the VLC technologies, LED-to-LED VLC, is a technology that applies LEDs to both a transmitter and a receiver. In this study, we demonstrate LED-to-LED VLC technology between a vehicle headlamp and a traffic light. We employed LEDs of different colors in the receiver and analyzed the theoretical channel capacity by measuring the 3-dB bandwidth, signal-to-noise ratio (SNR), and channel capacity. The communication performance was confirmed by measuring the bit-error rate (BER) as a function of the data rate. Studies have demonstrated that LED-to-LED VLC is feasible in the field of vehicle communication and is anticipated to be utilized for communication or data collection on the road.