Thread: Nokia prototype recharges batteries with radio waves
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attila77 is offline attila77
2009-06-16 , 22:25
Posts: 3,319 | Thanked: 5,610 times | Joined on Aug 2008 @ Finland
#9
Originally Posted by tso View Post
the physics involved?
a jammer is a active transmitter that sends a stronger signal then the one you want to recieve.
Almost, although it's not related to power - it means decreasing signal to noise ratio of a signal (altough done by emission most of the time as it's the easiest way of achieving that goal). I admit being somewhat free with the terminology

as for it being a sink, you will need a wall of phones more or less, and stand in the direct "shadow" of that wall.best way to envision it is like a thin piece of fabric in front of a lamp. it may produce a darker area on the opposite wall, but it will not darken out the whole room unless you basically wrap it around the lamp...
No, it doesn't work that way, unfortunately Radio waves propagate differently than light - that's why you use antennae that are very different, to, say, optical telescopes. Of course, the actual difference varies with the frequency, but it's far from the lamp example -> it's a bit like a magnet drawing metallic particles, the affected area is much larger than just the actual antenna. Now, if these buggers want to harvest a consistent 50mW out of thin air, they HAVE to cover a large area, not just a 'speck' on the back of the set (either that, or we're already glowing in the dark )