Researchers from Singapore and Japan have used Wi-Fi signals to power an LED, demonstrating the opportunities in harnessing power from the widely used frequency.
The team from the National University of Singapore (NUS) and Japan’s Tohoku University (TU) argue that excess WiFi signals are under-utilised and could be tapped for alternative uses.
In a paper published in Nature they document the development of a technology that uses tiny smart devices known as spin-torque oscillators (STOs) to harvest and convert wireless radio frequencies into energy to power small electronics.
Professor Yang Hyunsoo from the NUS Department of Electrical and Computer Engineering, who spearheaded the project, said: “We are surrounded by WiFi signals, but when we are not using them to access the Internet, they are inactive, and this is a huge waste. Our latest result is a step towards turning readily-available 2.4GHz radio waves into a green source of energy, hence reducing the need for batteries to power electronics that we use regularly. In this way, small electric gadgets and sensors can be powered wirelessly by using radio frequency waves as part of the Internet of Things. With the advent of smart homes and cities, our work could give rise to energy-efficient applications in communication, computing, and neuromorphic system.”
The research was carried out in collaboration with the research team of Professor Guo Yong Xin, who is also from the NUS Department of Electrical and Computer Engineering, as well as Professor Shunsuke Fukami and his team from TU.
Photo via the National University of Singapore. Shows Professor Yang Hyunsoo (left) and Dr Raghav Sharma (right), the first author of the paper, holding a chip embedded with about 50 spin-torque oscillators.