A team of researchers from the National University of Singapore and Japan’s Tohoku University came up with a technology to harvest WiFi signals using spin-torque oscillators (STOs). These are very small devices that generate microwaves and can convert wireless radio frequencies into energy. Using the STOs, the scientists were able to power a LED without the need for a battery, which gave them hope for many other future applications.
In their experiment, researchers used eight STOs connected in series and converted the 2.4 GHz electromagnetic radio waves into a direct voltage signal. The signal was transmitted to a capacitor which lit up a 1.6-volt LED. They charged the capacitor for only five seconds but it managed to light the LED for an entire minute, even after the WiFi was switched off.
If this technology gets implemented, we’ll be able to use WiFi to power small electric devices just by being within the range of a WiFi, which can be up to 100 meters (328 feet). This way, WiFis could be used for more than just giving us access to the internet.
This would significantly reduce the need for batteries to power electronics and we would be able to power small gadgets as part of the Internet of Things, according to Professor Yang Hyunsoo from the National University of Singapore. This technology could have applications in communication, neuromorphic systems, and computing, the professor added.
Scientists assure us that just by harvesting the WiFi signals you can’t decrypt them so security is not an issue.
The research required $1 million in funding and around three years to reach these results. The team plans on continuing the study to further improve the technology and find even more applications for it.