The large-scale deployment of Internet of Things (IoT) leads to a massive use of batteries for energizing the IoT devices. The chemical components of these batteries threaten to have a huge environmental impact on the Earth. This leads to the emergence of demand for battery-free devices. I make a step forward for enabling battery-free IoT devices through the convergence of two emerging technologies: LiFi and radiofrequency (RF) backscatter.

In this talk, I will introduce PassiveLiFi, a battery-free system that uses LiFi to transmit RF backscatter at a meagre power budget. It includes the first LiFi transmitter that implements a chirp spread spectrum (CSS) using the visible light spectrum. A small bank of solar cells is used for communication and harvesting, and reconfigure them based on the amount of harvested energy and desired data rate. Experimental results with an RF carrier of 17 dBm show that we can generate RF backscatter with a range of 80.3 meters/𝜇W consumed in the IoT device, which is almost double with respect to prior work.

This talk can be supported by reading our recent published paper: Muhammad Sarmad Mir, Borja Genoves Guzman, Ambuj Varshney, and Domenico Giustiniano. 2021. PassiveLiFi: rethinking LiFi for low-power and long range RF backscatter. In Proceedings of the 27th Annual International Conference on Mobile Computing and Networking (MobiCom ’21). Association for Computing Machinery, New York, NY, USA, 697–709.

About Sarmad Mir

Muhammad Sarmad Mir is a PhD researcher at IMDEA Networks Institute, Spain. He received his BE Electronics Engineering degree from Pakistan and a Joint MSc in Smart Systems Integration under the Erasmus+ scholarship from Europe. He is a recipient of the Marie Sklodowska-Curie Innovative Training Networks scholarship for ENLIGHTEM project. His research interests include Visible Light Communication, Radio Frequency backscatter communication, Battery-less tag design and Smart Systems.

This event will be conducted in English