Wireless Charging Start-Up Claims 30-Foot Radius 242
Lucas123 writes "At Disrupt this week, Ossia Inc. demonstrated for the first time its wireless charging technology that founder Hatem Zeine said has a 30-foot radius and, like WiFi, can charge through walls and 'around corners.' The technology, still in prototype phase, uses the same spectrum as other wireless standards, such as WiFi and Bluetooth. The Cota wireless charging system includes a charger and a receiver — either a dongle device or chip-tech integrated into a product, such as a smartphone or battery. While it has yet to be miniaturized, Zeine said the wireless technology will eventually be small enough to fit into a AAA battery or any portable electronic device. While the technology has wider industrial implications, as a consumer product, a charging unit will likely sell for around $100, he said."
Potential Snake Oil (Score:5, Informative)
Re:Holy EMF Batman? (Score:5, Informative)
I think this is the best idea I've seen since I invented it almost 100 years ago! [wikipedia.org]
Sincerely yours, Nikola Tesla
FTFY.
Nothing new (Score:1, Informative)
Nikola Tesla demonstrated a 100 Watt light bulb being lit 92 miles away from his Colorado Springs lab about 100 years ago.
30 feet?
Ha!
Re:No thanks, I will just use the neighbors (Score:1, Informative)
Getting it to sum to 1W at only the selected location is not something they can guarantee without accurately mapping out the space. And doing it dynamically if there are people moving is something else. Lots of trickey math and I doubt they can avoid a good bit of leakage.
Ah, but the trick is to not do any math. You have the charging device send out a quick RF beep. The charger looks at the phase and amplitude of that signal on every antenna element and uses that to for the returned energy beam. You do that often to deal with things moving. It's how MIMO works. Still, you need an insane number of actively controlled elements to make this efficient and focused.
Re:Holy EMF Batman? (Score:2, Informative)
Re:The "2.4 GHz resonance frequency" thing is a my (Score:4, Informative)
It may not be technically the resonant frequency of water, but there is something special about it:
The 2.45 GHz is a kind of useful average frequency. If the frequency was much higher then the waves would penetrate less well, lower frequencies would penetrate better but are absorbed only weakly and so once again the food would not absorb enough energy to cook well. [schoolphysics.co.uk]
My understanding is that the 2.4Ghz band was assigned for unlicensed use because it was already cluttered with things like microwave ovens and was, therefore, undesirable for licensed use.
Re:Safety? (Score:2, Informative)
Incorrect... If nothing absorbed it, you couldn't receive 5.8GHz Wifi signal. Conductors with a similar length to the wavelength or half wavelength will absorb it, that's how receiving antennas work, they usually either match the wavelength, half wavelength or quarter wavelength. The wavelength of an EM wave at 5.8GHz is around 5cm. If you have anything conductive with a length of around 1.2cm to 5cm, it will absorb power from a 5.8GHz signal.
Re:Supercharging the cells with ions ! (Score:4, Informative)
What kind of super-ionization will it do to our body cells ?
None, because photons with energy on the order of 1-10 ueV don't ionize anything.