Using Radio Waves to Power the IoT

By August 25, 2014 1 comment
Wifi backscatter IoT sans batterie

Researchers from the University of Washington, in Seattle, USA are preparing to launch a startup to commercialise a technology which enables simple connected objects to communicate and connect to the Internet without the need for battery power.

Instead of trying to produce slimmer and more flexible batteries which use less energy, or which recharge themselves, why not just get rid of batteries altogether in connected objects? It now appears that this ideal situation can in fact be achieved by using existing WiFi signals – both as a means of communication and a source of power. Engineers from the University of Washington have been carrying out research which seems set to enable small objects to communicate with each other. This time, the research is about getting them a connection to the Internet.

Self-powering connected objects

The Washington U researchers call their system ‘Ambient Backscatter’. This innovative approach draws on existing radio frequency (RF) signals as a power source, and then uses existing WiFi infrastructure to provide connectivity to these battery-free objects. The novel feature of this latest research is the capture and ‘repurposing’ of wireless signals. To get around the fact that power sourced at a distance is insufficient to create an Internet connection, Ambient Backscatter bridges ‘RF Powered Devices’ with the Internet. The technology captures RF signals from a WiFi router close by and transmits data in binary digits by absorbing or reflecting these signals. As the devices communicating with each other do not have to generate their own RF, the system uses very little power.

Facilitating the spread of the IoT

At the moment the prototype devices built by the Washington team can communicate with a WiFi hub at a distance of two metres, and the researchers are now aiming to extend this to twenty metres. Their example is a connected watch, which can download emails and transmit data to a personalised spreadsheet on Google. This process only works for objects able to run on low power, but it does bring us a little closer to a world where our Internet-connected objects can interact with each other. The chief current obstacle delaying the day when we can run all our connected objects via a single app and enjoy a truly streamlined user experience is the fact that standards differ from one manufacturer to another.

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1 Comment

Actually, there is another (and more powerful) Ultra Low-Power WiFi technology from UCLA & JPL :

Submitted by Gweltaz LE COZ (not verified) - on August 26, 2014 at 12:21 am

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