Scientists have invented Passive Wi-Fi that requires almost no power

Home automation enthusiasts rejoice!

Computer scientists and engineers at the University of Washington have developed Passive Wi-Fi, a system that uses 10,000 times less power than ordinary Wi-Fi devices. Operating using only 10s of mircowatts, Passive Wi-Fi could become an important technology in a connected world that wastes so much energy.

Current modems and routers contain components that handle the digital and analog aspects of sending radio waves such as Wi-Fi. The digital components have become extremely efficient as technology has improved but the analog components have remained power-hungry.

Rather than having lots of power-intensive routers throughout a building, Passive Wi-Fi requires only one that can be plugged into a wall-socket as usual. The other passive sensors don’t require the analog components as they only reflect the WiFi packets further.

One wall-powered unit handles the analog signal generation, while low-power Passive Wi-Fi devices simply reflect Wi-Fi packets. Image © University of Washington

The researchers were able to connect a smartphone to a Passive Wi-Fi unit over 100 ft away. It’s also considerably faster than Bluetooth. Some traditional Wi-Fi technology sends signals further and transfers data faster, but obviously uses a lot more power than it needs to. Passive Wi-Fi can operate on almost no power, which could be great news for the future of home automation and the Internet of Things.

You can learn more about Passive Wi-Fi from this video produced by the University of Washington:

Main image © University of Washington