Networking & Wireless

U Washington Researchers Develop Energy-Efficient Wi-Fi

• By Leila Meyer
• 03/01/16

A team of computer scientists and electrical engineers at the University of Washington has developed a passive Wi-Fi system that can generate 802.11b Wi-Fi signals using 10,000 times less power than present-day Wi-Fi and 1,000 times less power than Bluetooth Low Energy and ZigBee, according to a news release on UW's site.

Traditional Wi-Fi technology uses both digital and analog components. While the digital components are highly energy efficient, the analog ones are not. Passive Wi-Fi solves this problem by decoupling the digital and analog components of Wi-Fi transmissions, assigning the power-intensive analog functions to a single networked device that is plugged into a wall outlet. An array of sensors produces the information packets for transmission by reflecting and absorbing the signal with a digital switch, according to a news release from UW. The sensors are capable of communicating with any Wi-Fi enabled device.

"All the networking, heavy-lifting and power-consuming pieces are done by the one plugged-in device," said Vamsi Talla, an electrical engineering doctoral student who worked on the project. "The passive devices are only reflecting to generate the Wi-Fi packets, which is a really energy-efficient way to communicate."

In addition to reducing battery consumption on smartphones and tablets, Passive Wi-Fi has the potential to support the Internet of Things by enabling household device and wearable sensors to communicate using minimal power. The MIT Technology Review has named passive Wi-Fi on its list of 10 breakthrough technologies of 2016.

The computer scientists and electrical engineers who developed Passive Wi-Fi will present a paper about the technology at the at the 13th USENIX Symposium on Networked Systems Design and Implementation in March. The paper is available as a free, downloadable PDF from the University of Washington's site.