The idea is straightforward. Do you think the energy specification "5 milliwatts" is correct? Is the prediction of "50 milliwatts" reasonable? Mainly curious, Thanks.
"...a cell phone that recharges itself using a unique system: It harvests ambient radio waves from the air, and turns that energy into usable power. Enough, at least, to keep a cell phone from running out of juice... harvesting ambient electromagnetic energy is never going to offer enough electricity to power your whole house or office, but it just might be enough to keep a cell phone alive and kicking. Currently Nokia is able to harvest all of 5 milliwatts from the air; the goal is to increase that to 20 milliwatts in the short term and 50 milliwatts down the line..."