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Rethinking LiFi for Low-Power and Long Range RF Backscatter

Interest in zero-energy/low-energy IoT is gaining ground as the industry tries to introduce more of these with minimal impact to the environment. A research team of IMDEA Networks Institute has introduced Internet of Things (IoT) devices that communicate without any batteries and harvest energy and receive data through visible light. A news article reported:

This represents a new step towards making battery-free devices a reality, through the convergence of two emerging technologies: LiFi and radio frequency (RF) backscatter. Potential applications include smart homes, smart cities, and smart agriculture.

It is expected that more than 64 billion IoT devices will be deployed by 2025, and they will work with batteries. The chemical components of these batteries threaten to have a huge environmental impact on the Earth. There is a pressing need to find a solution for removing the batteries without affecting communication performance and IoT services.

IMDEA researchers propose that IoT devices will operate with the energy provided by Light Emitting Diodes (LEDs) and any other light source, and data provided by modulating these LEDs, a concept called LiFi, and that IoT devices will send data back by reflecting and modulating the RF coming signals already present in the environment, a passive and low-energy transmission technique called RF backscatter.

You can read the complete article here. You can download the paper from here or PDF from here.

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