How Wi-Fi Will Power Tomorrow’s Battle Gear

Researchers from the University of Washington unveiled a paper, "Powering the Next Billion Devices With Wi-Fi," that describes how to power a small camera with a Wi-Fi signal. In essence, the camera's 2.4-GHz antenna becomes an energy harvester that transforms radio frequency signals into DC power. Unlike some other ambient power schemes, this one doesn't interfere with the functioning of the router. But is this breakthrough relevant for the men and women who lug hot and heavy batteries across mountaintops in places like Afghanistan?

Wi-Fi power has "any number of applications" on the battlefield, said Paul Roege, a retired Army colonel who also served as chief of the Army Operational Energy Office. Those include "inductive charging pads in a vehicle seat that could recharge soldier batteries on the ride to battle to a laser beaming power from an aerostat to a small patrol, either moving or stopped." Over the last few years, he said, he has encouraged the Army to explore wireless energy for a variety of uses. "The Army actually has it on their screen today," he said.