Dipartimento di Ingegneria informatica, automatica e gestionale

Visible Light Communication (VLC) offers a key alternative to the spectrum-challenged Radio Frequency (RF)-based forms of data transmission by tapping an unutilized and unregulated frequency band. Carefully designed low-cost VLC devices have the potential to enable the Internet of Things (IoT) at scale by reducing the current RF spectrum congestion, which is one of the major obstacles to the pervasiveness of the IoT. Wide adoption of VLC devices is however hindered by their current shortcomings, including low data rate, very short range and inability to communicate in noisy environment. In this paper we describe a new software-defined VLC prototype named VuLCAN for Visible Light Communication And Networking that overcomes these limitations. VuLCAN is based on an ARM Cortex M7 core microcontroller with fast sampling analog-to-digital converter along with power-optimized Digital Signal Processing (DSP) libraries. Using BFSK modulation, the prototype achieves a data rate of 65 Kbps over a communication range of 4.5 m. VuLCAN also provides robust and reliable communications in highly illuminated environments (up to 800 lux) using only a low power Light Emitting Diode (LED), largely exceeding the capabilities of current state-of-the-art prototypes.