Wi-Fi Backscatter Could Eliminate Need For Batteries

What if you could connect to the Internet without having to spend money on batteries or electricity? Thanks to engineers at the University of Washington, you may soon be able to do just that.

Building on previous research (that showed how low-­powered devices could run without batteries using energy from radio, TV and wireless signals in the air), these engineers designed a communication system that provides Internet connectivity to devices. The technology, called Wi-­Fi backscatter, would be the first of its kind to connect battery­-free devices to the Wi­-Fi infrastructure, harnessing energy from radio frequency signals and existing Wi­-Fi infrastructure.

The challenge in this research came from the fact that conventional, low­-power Wi-­Fi uses three to four orders of magnitude more power than can be harvested from wireless signals. Instead, engineers and researchers developed an ultra­lo power tag prototype that has an antenna and circuitry that can communicate with wireless­-enabled laptops and smartphones – all the while consuming a negligible amount of power.

The tags “look” for Wi-­Fi signals that are moving between a router and the laptop or smartphone. They then encode data by reflecting (or not reflecting) the wireless signals from the router, and, simultaneously, slightly changing it. The wireless-­enabled devices would detect these changes and receive data from the tag.

Joshua Smith, a University of Washington associate professor of computer science and engineering, explains how this process is successful. “You might think, how could this possibly work when you have a low-­powered device making such a tiny change in the wireless signal? But the point is, if you’re looking for specific patterns, you can find it among all the other Wi-­Fi reflections in an environment.”

This means those smart watches will be able to download emails or load data onto a Google spreadsheet. In the not­so­distant future, an “Internet of Things” can be a reality, thus extending connectivity to billions of devices. This, in turn, would give us the ability to monitor and track infrastructure, health, and even the status of our homes.

“If the Internet of Things devices are going to take off, we must provide connectivity to the potentially billions of battery-­free devices that will be embedded in everyday objects,” said Shyam Gollakota, a University of Washington professor of computer science and engineering. “We now have the ability to enable Wi­Fi connectivity for devices while consuming orders of magnitude less power than what Wi­Fi typically requires.”

At PreScouter, we help companies find the most innovative solutions to any challenge. Contact us today and challenge us with yours!