Wi-Fi State

Powering our devices in an increasingly electronically connected existence is no simple issue. Batteries and tethered connections to outlets have long been the standard. Yet, dead batteries and damaged wiring often lead to toxic waste. What if a pre-existing source of energy can be harnessed to sustain our devices? What if the transmissions our electronics already give off to communicate (e.g. radio frequency signals) can be used to power themselves?

Progress in this field is being made rather quickly.  A company called Energous already offers a way to charge any battery operated device, provided it runs on less than 10 watts, by creating a radio frequency system much like Wi-Fi.  However this requires the production, purchase and installation of additional equipment, making this option far from user friendly.

A team of researchers at University of Washington has recently published new research and results demonstrating the utilization of pre-existing signals as a source of power for the device that produces them.

Two functions, One signal

The team’s new technique, called Ambient Backscatter, uses signals already present rather than creating new transmission.  Shyam Gollakota, lead researcher and assistant professor of computer science and engineering at UW, explains, “We can repurpose wireless signals that are already around us into both a source of power and a communication medium.”


While the nature of this technology is breathtaking, it’s important to bear in mind its early stage. It currently has yet to function past a maximum distance of 28 feet and has only been demonstrated to works with small vessels, like rechargeable batteries.

Despite these present proximity limits, there is significant promise for improvement. Future innovations could include increasing the maximum range further to make the technology available for more power intensive objects, such as your iPhone. Eventually it will be possible to place sensors deep within structures and have them report on information independently. Examples of this include smart homes or infrastructure to determine status and structural stability. One could even imagine an entirely connected world of smart objects with everything being on a self-sustained network.

Having just founded a startup called Jiva Wireless, the team behind Ambient Backscatter is poised to further advance this technology. With an estimated time to market of as little as 12 months, we can confidently expect to see this technology seep into our daily lives relatively soon.

University of Washington


Sources: Wired, UW Today, The Seattle Times, Energous, FCC.gov
Featured Images: NCTA, University of Washington
Featured Video: UW Sensor Systems Laboratory

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