Novel detection technique for smartphone to smartphone visible light communications

This paper proposes a novel detection technique for the Android-based smartphone to smartphone visible light communications system. In this system, data is encoded into images and displayed on the flashing transmitter's screen. The receiver captures the flashing images from the transmitter and performs a frame subtraction to detect the transmitted data. A Canny edge detector is then applied and the corners of the transmitter are located before performing a perspective transformation. The system is implemented on Android platform and a range of experiments are carried out to evaluate the effect of several parameters on the detection such as the brightness of flashing screen and its rise time. We demonstrate a link with a possible 100 kbps data transmission capability