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A comment on Router can power your devices wirelessly from 15 feet away.

Re:Router can power your devices wirelessly from 15 feet away by Mithaldu on Friday January 09, 2015 @04:04AM (#8861375)
They claim to reach 70% efficiency, by transmitting power on the wifi bands, and compare it to a charging mat (90%), and tout 15 feet distance, but leave out one detail:

How quickly efficiency drops off.

I suspect you only get 70% if your phone is literally on top of the router, and that the efficiency drops of very quickly to 0 as you approach the range limit.

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Re:Router can power your devices wirelessly from 15 feet away by richardwhiuk on Friday January 09, 2015 @05:08AM (#8861542)
The suspicion is that the 70% efficiency is how much of the power arriving at the phone can be used for charging it, not much the transmitter is supplying.
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Re:Router can power your devices wirelessly from 15 feet away by johngd on Friday January 09, 2015 @09:22AM (#8862302)
My car's USB port can barely charge my Samsung Galaxy 5.... I can't imagine how long it would take via radio wave.
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