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Wireless charging standards thrown into chaos by stealth entrant, Cota

by Stuart Robinson | 9月 12, 2013

Every so often a technology development comes along that makes you think "wow, that could really change the world!" That thought occurred to me this week when I read about a new wireless charging technology...

Ossia, a company that has been in stealth mode developing yet another wireless charging technology, has finally revealed to the world what it has been working on in secret for the last six years.

The technology, called Cota (which probably stands for "charging over the air" although I haven't seen confirmation of that yet), was demonstrated on-stage at a TechCrunch event called Disrupt in San Francisco last weekend. Cota's inventor, Hatem Zeine, showed his system charging an iPhone from a distance of about 10 feet and said that it would work round corners and through walls, like Wi-Fi. In fact, like Wi-Fi, it also works on the same 2.4GHz frequency, delivering a focussed beam up to 1 Watt at a maximum distance of 30 feet (10 metres).

The prototype transmitter is huge and incorporates half a million components, but will be shrunk to the size of a desktop PC in the next year or two and will cost a little over $100 according to Zeine.

The prototype receiver will also be shrunk into a single chip and could be embedded within a cellphone, TV remote control, games controller, Bluetooth headset, smoke detector or anything else that is currently battery-powered. 

One of the many clever aspects to Cota is its configurability; again, like Wi-Fi you can set up your transmitter to be open to the public or closed to only one or a few devices.

Some questions still lurk in the back of my mind though:

- How safe is it? It's claimed to be inherently safe, "as safe as Wi-Fi", but then not everyone is convinced about the long-term health effects of Wi-Fi either.

- How efficient is it? Existing wireless charging standards are up to 70-80% efficient. It will need to be as good. Zeine claims that in the commercial version of the system the more transmitters there are the better will be the efficiency.

- How will it work in a vehicle? The automotive industry is embracing other wireless charging standards. The physical size of a Cota transmitter may be a problem for in-vehicle usage, unless the small individual components and transmitters can be dispersed within the vehicle.

The number of wireless charging standards was already high, and the addition of a new, potential disruptive one this week, must be a concern to the existing standards bodies, consortia and organisations:

- Qi, the standard with the most products on the market currently, is an inductive power solution that has been developed by the Wireless Power Consortium and has the backing of over 160 companies including TI, Fulton Innovation, NTT docomo and a host of handset manufacturers. We're aware of about 20 smartphones integrated with Qi so far and the list is growing. The WPC aborbed one of its competing standards, PowerbyProxi earlier this year; PowerbyProxi had developed a more loosely-coupled inductive system but pulled the plug on launching its own standard and joined the WPC in May 2013.

- A4WP, the Alliance for Wireless Power, is a consortium founded by Samsung and Qualcomm. Qualcomm's WiPower technology is incorporated into the company's new "Toq" smartwatch, and is based on the A4WP specifications. Intel's "Wireless Charging Technology" (WCT) will also be compatible with the A4WP standard.

- Power Matters Alliance, developed by Duracell Powermat, has a widely-used standard (Starbucks for example) that is partially compatible with Qi. Its downfall is its tightly-coupled operation with very little spatial freedom.

I've seen too many announcements over the years of promising battery technologies that are going to solve all of our smartphone-charging problems, and not seen any of them come to fruition yet, so I'm cautious about this announcement too, but cautiously optimistic.

With so many competing and incompatible wireless charging standards vying for space it's debateable whether any of them will succeed in the long-run. Wireless charging technology is still too immature (as this week's revelation by Ossia has demonstrated) for the industry to settle on one standard, but one standard is exactly what is needed if wireless charging is ever going to more than a niche fad. 

Stuart Robinson

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