Smooth transmission over unsychronized VLC links

Abstract

Screens and cameras on off-the-shelf personal devices have become widely available in recent years, which has prompted interest in exploiting the communication channels between them in the visible light band. However, the basic issue of frame synchronization in such systems has not been adequately addressed. As a result, the receiver is not guaranteed to detect and capture decodable frames under many settings, and the link would become unusable. In this work, we address this synchronization issue with a rateless code design across frames. Without modifying the hardware, the firmware or the driver, our application-level software-based approach, Smooth Codes, enables screen-camera pairs with any frame rate condition to transmit and receive data smoothly to achieve high throughput.