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Power Wireless Networking Technology

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."
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Wireless Charging Start-Up Claims 30-Foot Radius

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  • Holy EMF Batman? (Score:5, Insightful)

    by H0p313ss ( 811249 ) on Tuesday September 10, 2013 @05:39PM (#44813185)

    Is it just me or does this seem like a really bad idea?

  • Safety? (Score:4, Insightful)

    by NoKaOi ( 1415755 ) on Tuesday September 10, 2013 @05:42PM (#44813223)

    If you're blasting ~2.4ghz RF from one place to another, what happens when something absorptive gets in the way? If it can charge a smart phone, is it enough energy to burn you if you get in the way, or start a fire if it happens to be going through a nail in your wall?

  • by jandrese ( 485 ) <kensama@vt.edu> on Tuesday September 10, 2013 @05:42PM (#44813227) Homepage Journal
    How in the world are they going to push out significant amounts of power on bands with extremely strict transmission limits? It's going to take you all year to charge a AA battery from a 4000mW omnidirectional transmitter that's 10 meters away. Not to mention utterly destroying wifi and bluetooth signals for several hundred feet.
  • scary (Score:5, Insightful)

    by dmitrygr ( 736758 ) <dmitrygr@gmail.com> on Tuesday September 10, 2013 @05:42PM (#44813233) Homepage
    without beamforming - inverse square law says no
    with beamforming, one must remember that beamforming cannot focus in just one place, smaller but still constructive maxima will exist elsewhere. what wants 1/3 of a watt focused on their gonads accidentally?
  • by jandrese ( 485 ) <kensama@vt.edu> on Tuesday September 10, 2013 @05:50PM (#44813357) Homepage Journal
    It's still noise to the wifi card unless it is specifically built to filter out that extra carrier somehow. Theoretically it is possible, but no consumer card is going to support it today. It's kind of like talking to someone and then having a guy with an air horn 10 feet away start blowing it constantly. With proper processing you could pick the conversation back out of the noise, but it's not something your average person is going to be able to do.
  • by Anonymous Coward on Tuesday September 10, 2013 @06:01PM (#44813513)

    No, you were right the first time. 1 watt into 6db antenna = 36dbm = 4 watts erp. PtP systems can go higher with a 1db drop in power for each 3db increase in antenna gain. Still tis seems screwy. Enough power to charge a Li-Ion battery at more than 10 feet distance in less than a week would be of major health concern. Like disabling the lockouts and running your microwave oven with the door open.

  • The actual tech (Score:5, Insightful)

    by AdamHaun ( 43173 ) on Tuesday September 10, 2013 @07:00PM (#44814145) Journal

    I dug up what looks to be the main patent [ipexl.com] for the technology from 2008:

    The microwave energy is focused onto a device to be charged by a power transmitter having one or more adaptively-phased microwave array emitters. Rectennas within the device to be charged receive and rectify the microwave energy and use it for battery charging and/or for primary power. A communications channel is opened between the wireless power source and the device to be charged. The device to be charged reports to the power source via the channel a received beam signal strength at the rectennas. This information is used by the system to adjust the transmitting phases of the microwave array emitters until a maximum microwave energy is reported by the device to be charged. Backscatter is minimized by physically configuring the microwave array emitters in a substantially non-uniform, non-coplanar manner.

    I don't know enough about antennas and E&M to evaluate that. Any help here? According to the articles it gets ~10% efficiency at 10 feet and receives (?) 1 watt at 30 feet.

    On to the possible crank warning signs:
    * According to his LinkedIn profile [linkedin.com], he's spent his whole career being a CEO and/or (later) doing software testing at Microsoft.
    * He's identified as a physicist, but all he has to show for it is a bachelor's in physics from the University of Manchester (where he also "studied ... computational linguistics"). No graduate degree or research career.
    * Twenty years after he gets his degree, having done nothing but software, he's suddenly producing miraculous hardware based on cutting-edge physics?
    * Charger is hidden behind a curtain during a demo.
    * Charger is six feet tall, but they're going to consumerize it to the size of a desktop PC in two years, when it will cost ~$100.
    * Replacing all their off-the-shelf hardware with custom-built optimized hardware? No problem!
    * Current fridge-sized charger has 200 transmitters, but when consumerized will have "20,000 transmitters in an 18-inch cube".
    * The only public demo makes an iPhone declare itself to be charging. No electrical test equipment or data shown. No real evidence that it does anything.
    * Claims the power goes through walls just like Wi-Fi, even though Wi-Fi signal strength can drop by orders of magnitude when it goes through walls.
    * Charger only gets 10% efficiency from 10 feet away in open air, but this is never mentioned as an obstacle. Come to think of it, no technical obstacles are mentioned at all.
    * This:

    “In wave theory and electromagnetic systems, you don’t get linearities everywhere,” he added, describing the science behind Cota. “There are situations where double could mean for more, like double could mean square, or 3 plus 3 apples could result in a net total of 9 apples, so to speak. When you move from the linear version to the power version, things happen that were quite surprising.”

    I don't know, maybe I'm being too hard on the guy. Maybe he's been doing physics and electronics as hobbies all this time, actually did come up with a workable idea, and used his management experience to drive the development of a real product. Maybe they really will have a commercialized version ready in a couple months and I'll have to eat crow. I just can't help but feel skeptical of people who announce their world-changing new product before it actually is a product.

  • Efficiency? (Score:2, Insightful)

    by Kal Zekdor ( 826142 ) <kal.zekdor@gmail.com> on Tuesday September 10, 2013 @07:54PM (#44814633) Homepage

    Even if this technology works reliably, on which I have my doubts, (not to mention the potential health risks if this thing accidentally irradiates someone by mis-aiming its EM beam), did anyone there stop to consider the efficiency of sending power through EM bursts at receivers through 30 feet of air, plus a wall or three? Can you imagine just how much energy is wasted through dissipation? We don't need less efficient means of transporting electricity. Anybody who uses this thing is going to use 3 - 10 times more electricity to charge their devices than just using a cable. (Numbers pulled from a remote inspiration device 30 feet away, but the actual amount of loss is somewhat irrelevant; the inverse square law guarantees it will be substantial.)

    It's a bad sign when I'm the one pointing out the environmental dangers of new tech.

  • Re:Links ! (Score:5, Insightful)

    by LordLimecat ( 1103839 ) on Tuesday September 10, 2013 @08:08PM (#44814727)

    No, because the sun bombards us with far more of that crap than a 30mW router will.

    Heres a nice summary [wikipedia.org]

    Im not sure why radio isnt listed, but infrared, visible, and ultraviolet are all more energetic and "damaging" than radio waves.

    The total amount of energy received at ground level from the sun at the zenith is 1004 watts per square meter, which is composed of 527 watts of infrared radiation, 445 watts of visible light, and 32 watts of ultraviolet radiation.

    So a few watts of power floating around your home is probably not that much to worry about.

    Also, those two links you provided are both from primary school students--not even highschoolers-- so Im gonna say its probably not on the same level as the existing evidence against WiFi causing harm.

  • Re:Links ! (Score:5, Insightful)

    by Ferzerp ( 83619 ) on Tuesday September 10, 2013 @08:12PM (#44814749)

    Not really. That was an *extremely* poorly controlled experiment by grade school students. Magically, no one else has produced similar results in an actual controlled study.

    If your *only* evidence is a single experiment performed by individuals with barely rudimentary training in the sciences, you might want to consider that it is your bias causing you to readily accept the outlier as opposed to the norm.

"I have not the slightest confidence in 'spiritual manifestations.'" -- Robert G. Ingersoll