A new communication system that uses radio frequency signals as a power source while reusing existing Wi-Fi infrastructure to provide internet connectivity to smart devices has been developed by researchers at the University of Washington.
The new system, dubbed Wi-Fi backscatter, is the first that can connect battery-free devices to Wi-Fi infrastructure, according to the researchers.
University of Washington assistant professor of computer science and engineering Shyam Gollakota believes the technology could act as a mechanism to revolutionise the emerging internet of things (IoT) sector, by wirelessly providing power to connected smart devices.
"If 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 Gollakota. "We now have the ability to enable Wi-Fi connectivity for devices while consuming orders of magnitude less power than what Wi-Fi typically requires."
The new system is built on previous research showing how low-powered electronic devices, including wearable technology, could operate without batteries by harnessing energy from ambient radio, television, and other wireless electromagnetic signals in the air.
According to the university, this latest development takes the research a step further by connecting each individual device to the internet, which was previously not possible, as conventional low-power Wi-Fi consumes three to four orders of magnitude more power than could be harvested from these wireless signals.
However, the researchers have developed an "ultra-low power tag prototype", which has an antenna and circuitry that can communicate to Wi-Fi-enabled laptops or smartphones — all while consuming negligible power.
"You might think, how could this possibly work when you have a low-power 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," said Joshua Smith, an associate professor of computer science and engineering and of electrical engineering at the university.
The researchers will publish their results at the Association for Computing Machinery's Special Interest Group on Data Communication‘s annual conference this month in Chicago. The team also plans to start a company based on the technology.