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Using ‘reflected’ signals could have a big impact on your phone’s battery life.
Electrical engineers at the University of Washington have come up with a new type of Wi-Fi hardware that uses 10,000 times less power than existing technology, Wired reports. That could have big implications for mobile and embedded applications, helping smartphone batteries last longer, reducing the power demands of devices in the Internet of Things, and ultimately making internet connectivity practical for a much wider range of devices.
The technology, dubbed “Passive Wi-Fi,” relies on a phenomenon known as “backscatter.” While most Wi-Fi connections currently require two powered radio signals, the new standard would need only a single powered device, which would generate a single-frequency signal. “Passive” devices in the vicinity could then, according to the paper outlining the work, ‘reflect’ that tone, while also shifting it to synthesize wireless transmissions.
The researchers built prototypes of their system, and found that transmissions from their passive devices could be decoded by existing cell phones and other Wi-Fi receivers. That means that even with present-day receiver hardware, Passive Wi-Fi could be used to extend an existing wireless network while saving electricity.
But returns could be much greater if Passive Wi-Fi were eventually integrated into mobile and connected devices themselves, allowing them to send data using next to no power. Wired quotes Bryce Kellogg, one of the paper’s authors, saying that “Passive Wi-Fi would improve battery life by about as much as turning your Wi-Fi off.”
Wireless communication is typically a large part of a smartphone’s power consumption, so the impact could be substantial. And with battery innovation proving to be a huge challenge, reducing power consumption is key to making mobile devices less dependent on plugs. The impact on the Internet of Things could be even bigger, allowing embedded sensors and transmitters to be much smaller, lighter, and longer-lasting.
Written by David Z. Morris of Fortune