Competition is key to technological advancement. Competing standards exist because different companies how different ideas about how wireless charging should be done. The market will ultimately determine which standard will last.
In my opinion, A4WP is the strongest contender thanks to their use of magnetic resonance for power transfer. WPC and the lesser-known PMA are currently focused on inductive charging, which as mentioned in the article, has significant disadvantages in comparison.
In addition to having the better technology, A4WP also has the backing of three very big names: Qualcomm, Intel, and Samsung.
Competition is good. It weeds out the inferior products and standards.
The magnetic resonance method is interesting. Although the inductive method used by Qi is electrostatic induction, not to be confused with electromagnetic induction, it is really just a modernization of Nikola Tesla's early 20th century work with improved efficiency coming from the use of much higher frequencies.
I would think that if anyone can get their wireless charging system into laptops, tablets, and readers then the market could be almost ready. It takes a lot of infrastructure to make a standard successful. If one system is cheaper to implement or better at charging (aka faster) then that could be a key differentiator. So far, I have not seen any compelling systems proposed. 22 Watts delivered is not bad for a cell phone but what about a laptop or tablet? I wonder if this system can deliver more say 100W or 150W?
Competing wireless charging systems and the need to implement the wireless system on the device side (receiver) and power system side (outlet) suggest that we have a long way to go. If the devices require an external adapter "coil" as the wireless receiver, then the extra baggage doesn't really do much good. It might as well be a supplemental battery with a standard outlet cord. It seems like we still have a long way to go. I fear that we are moving towards vendor specific wireless charging protocols and the prospect of an array of wireless charging stations at home - just as we have an array of wired charging stations at home now.
A4WP includes a large number of Taiwanese players,
TI, Sandiak, NXP and BRCM.the latecomeers - Intel,
How many of these guys are serious about the
A4WP standard remains to be seen. Perhaps Samsung
will eventually come up with their own.
The photo on the cover of this story is of an ancient NON wireless charging mat that uses contacts on the custom battery cover of those Motorola RAZRs to make contact with those metal strips on the mat below.
Either way, A4WP is the way to go from my limited understanding and let's hope that AAPL adopts it too so we can be done with all their expensive accessories and charge our iDevices on the same pads as our Androids.
Hopefully MS/Nokia will adopt A4WP too for future Lumias.
Do we know what the efficiencies are with wireless charging ? I know there are losses in everything, but seems like in this age of making things cleaner and more efficient, wireless charging is just going to waste more electricity for a small trade off in convenience?
"wireless charging is just going to waste more electricity for a small trade off in convenience?"
Except that the user won't see it as a *small* increase in convenience.
Like most folks, I have a lot of devices that need to be charged. Every one seems to have a different charger and power connector, and I have a drawer full of chargers with stick on labels so I know what they are intended to charge. I'd love a one-size-fits-all charger that can adapt to what the device wants to see, and devices that can use it.
The "waste" of electricity would be a tiny price to pay.
I waste tons of electricity because of all the chargers I need to keep plugged in, and the inconvenience of unplugging those not in use (or even figuring out which ones they are, with cables all over the place).
Beyond that, one of the purposes of energy is to make things convenient. If you want to live in an inconvenient world, fine by me - but don't make me do the same in the name of some green god.
Competition is not always contrary to standardization. I agree that there may be a reason for non-compliance adding value above a standard (like Atheros did with their 108G).
But, industry designed in to a standard knowing that they would not have to redesign in less than a year in order to work well with the commodity/standards. Early adopters of 108G WiFi knew that it would work with the rest of the world of they just disabled the Atheros extension.
Imagine deciding you want to implement a product but, you are waiting for some standards before you do so. Imagine every vendors pedantic suborn decision that everyone must comply withe their implementation. Now imagine we wait another 3 years for these vendors to be winnowed down creating a defacto standard before we decide to use the feature. Welcome to competition...
Nobody seems to mention/talk about the efficiency which happens to be really poor. Very very poor. The real convenience should start with a universal wired charger adopted by all manufacturers so we don't get a new charger every 18 months with our new smartphones. A4WP or WPC, who cares, they all require coils on both sides, additional hardware and cost for a mediocre performance and energy waste for what? Showing off by saying your phone is charging in your pocket while driving? I'll pass.
As anyone who has ever designed a transformer (B/H field coupling) or capacitor(E field coupling) knows that fractions of a millimeter in the windings can make a huge difference in the coupling. So yes, if a handheld product can be designed so that the space between charger and pick-up coil or plate is on the order of 0.5mm or less, reasonable efficiency can be obtained.
Define reasonable efficiency. Note that Qualcomm's standard does not mandate a distance between the Rx and Tx coils. Its "advantage" is that there are no such constraints and the handsets can be positioned "casually" within several 10s of centimeters. WPC does but then you're back to the "mat".
I really do not see a bright future with wireless charging when compared with its counterpart, USB charging.
1) It needs additional hardware. Costwise, it will be more expensive.
2) The efficiency is poorer. Not environmental friendly. ( Note that almost every two years, there are tighter energy standards for power adaptors/chargers. The performance of wireless charging is far behind that)
3) The future improvement is limited. Since it operates with primary coupling coil and secondary coupling coil separated, this inherently leads to a lower efficiency and incur a lot of limitations. This is a constraint by physics.
4) Business model is another question. For a comodity USB adapter, one may get it with just a few USD and it can be used for a lot of devices. For wireless charging, one need to pay a higher premium for the transmitter and then, the lower cost on the receiver. The first seller to include the transmitter will add that cost to his own device ( while lowering the cost of the other portable devices ). Who does that? By the way, there are a lot of different standards, when I buy my computer with a transmitter of "A" standard but the phone I use is of "B" standard. Will I pay something extra unnecessarily ( for unused "A" transmitter? Or should I change to use a phone with "A" standard?
I am rooting for solar/light for both power and data. It'd be quite nice to just have PE cells that can capture extremely low level ambient light and PE cells that are fed into filters for the data path and wires are gone and much of the RF along with it.
Light is a wonderful broad-spectrum resource and we are troubled without it. Let's use it better!
Doesn't make much sense to me, since we are unable to "hold" our phones anyway. It seems the more logical approach is to have a universal dock. Motorola has been trying to do that of late with there various models. Sound, microphone, power, etc. are easily be accommodated with a microusb plug.
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