"Wireless charging pads use electromagnetic induction to juice up your phone. Both the pad and your phone contain wire coils: the pad draws current from the wall and runs it through the coil, creating an electromagnetic field. That field induces an electric current in your phone’s wire coil, which it uses to charge the battery.
However, the electricity being transmitted to your phone isn’t perfectly clean or ideal. It generates some noise, which can interfere with other wireless devices. That’s why the FCC (and regulatory bodies in other countries) set strict limits on wireless emissions.
Noise from a single coil might not be a problem, but each charging coil generates a slightly different waveform. When those waves overlap, the constructive interference intensifies their strength. Just like when two ocean waves collide and combine their height, radio frequencies can combine their intensity as they interact.
Managing these overlapping harmonic frequencies is incredibly challenging, and gets harder the more coils that you are integrating. From patent filings, it looks like Apple’s ambitious plan was to use considerably more coils than other charging pads on the market.
Rumors speculated that Apple was considering up to 32 coils—up from the fifteen shown in their conceptual patent filing.
Other multi-device wireless chargers place two or three coils side-by-side, but require you to fiddle with your phone to find the “sweet spot” over one coil for it to start charging. With AirPower, Apple was trying to create one large charging surface using overlapping coils, allowing it to power multiple devices from anywhere on the mat. But that introduces multiple challenges.
We asked an engineer with experience building wireless charging systems what obstacles Apple was working to overcome. “Over time, these harmonics add up and they become really powerful signals in the air,” explains William Lumpkins, VP of Engineering at O & S Services. “And that can be difficult—that can stop someone’s pacemaker if it’s too high of a level. Or it could short circuit someone’s hearing aid.” If Apple’s multi-coil layout was spinning off harmonics left and right, it’s possible AirPower couldn’t pass muster with US or EU regulations."
This makes sense. What is being described regarding electromagnetic interference is also what's known as superposition which is also the basis for beamforming, both for electromagnetic and physical (sound pressure). When properly engineered, beamforming can be used constructively to overcome the limitations described, but with some caveats. If Apple could detect the physical orientation of a device on the pad it could employ many smaller micro-coils and beamforming to replicate the same electromagnetic field that would be formed by a single larger coil in a conventional charger that has physical mechanisms like a cradle to ensure device orientation. It would be fairly straightforward to design a charging pad with many smaller micro-coils that optimizes the charging of a single device - iff the charging pad can determine or coerce the orientation of the device on the pad. But even this would be far from ideal because it would still be open-loop. If the device being charged were able to communicate back to the charging pad about the quality of the charging process the charging pad could auto-tune itself to the charging requirements and reduce spurious interference and shutdown unnecessary coils. Without device orientation detection and a feedback loop it's difficult to come up with a solution that works effectively. The feedback loop could be done out-of-band using NFC, but you can now see that this starts to ratchet up the complexity and cost and you have to ask yourself whether it's even worth it.
My feeling is that this problem is fully resolvable but not without advances in wireless charging technology on both sides. Trying to solve it on one side, i.e., smart charging pad, with no similar level of advancement on the device side is a severe constraint. Ultimately, if both the charging mat and devices have arrays of micro-coils and advanced beamforming it would be possible to selectively steer the charging beam to the device being charged and auto-tune the power needed based on the device also using beamforming on its side with a feedback between the charger and the device. Theoretically you could nix the pad completely and allow devices to be charged from across the room, say from a transmitter mounted in the ceiling that charges every device in the room. But every step down the path to the theoretical solution needs to be gated by the question: is this really worth the cost and effort?
Canukstorm - great find! I'm guessing that the charging pad's brains (controller) could detect when something is placed on the mat due to a shift in resonant frequency of the particular coil(s) when the device is over the coil(s).
Dewme - I briefly read the Wikipedia page on Qi, and it does not describe a method of (intelligent) communication between the pad and device(s), because I also wondered how the pad would know how to charge an iPhone at one level, an Apple Watch at another level, etc. unless the device would internally regulate its own charging current. Pumping full power for every detected device could be a radiation (FCC) nightmare.
The Qi page mentions 3 possible methods of "free positioning" charging of a device on a Qi pad (as opposed to "guided positioning" of current devices) - 1) a bundle of transmitting coils is used to generate a magnetic field at the location of the receiving coil only; 2) mechanical means to move a single transmitting coil underneath the receiving coil, 3) a technique called "Multiple Cooperative Flux Generators." The last method got my attention. See this link (PDF) for more information. I'm guessing that Apple went after the last method (which seems the most complicated to me). The PDF also mentioned that their test setup achieved "arbitrarily long free positioning" (what Dewme alluded to regarding charging across a room).
As inefficient as these charging mats are, I was surprised they ever wanted to get into this market to begin with.
To be honest, maybe I was naive, but when I first heard about wireless charging, I thought it would be charging where you could have your iPhone or whatever across the room and it would charge even if the base was located in the corner of the room. That sounds pretty convenient.
If somebody has to place their iPhone or whichever device precisely on a charging mat, then what's the difference between that and just sticking a damn cable into your phone?
I don't see the appeal in wireless charging, especially not for the added cost that it requires. I'm not seeing the benefit of it yet, but that's just my opinion.
[...] If somebody has to place their iPhone or whichever device precisely on a charging mat, then what's the difference between that and just sticking a damn cable into your phone?
Guys. I’m concerned about Apple. I see less and less innovation happening at Apple. Apple makes lots of money which is great. But the spirit has seemed to change from the innovate and change the world spirit of Steve Jobs to a more sensible “how can we make more money” approach. There was literally nothing new or interesting in that appleTV + announcement. Sad
The moment Oprah came up did it for me. This company isn’t about tech anymore - but dispersed over a 1000 wrong priorities.
This fixation on Apple needing to "innovate" is mind-boggling. What defines innovation? If their iPhones look different from one generation to the next, suddenly it's innovation? Apple invests HEAVILY in technology that you can't see! That's where the innovation is. So what if the outer appearance of the device looks the same... as long as they've moved the game forward inside and it's a better device for it. And that's been the case, year after year after year. Macs may have slipped slightly in the regular updates, but I think they are getting themselves back on track. I think the move to their new campus was a huge distraction, which is now behind us.
Innovation is also not having the fastest processor or the highest-megapixel camera. None of that matters if the devices as a whole performs poorly, and Apple excels at delivering devices that perform exceptionally with half the resources of the competition, yet continue to set the lead for processor performance.
So I don't think there's any reason to be concerned about Apple caring about tech. The only problem was a slowdown in Mac updates. But they are now caught up.
And innovation costs money, so we can't have our cake and eat it, too. You either get innovation or your get cheap (-ly made) products, not both. Apple products are expensive for a reason. We all hate it, but it's not pure greediness. The tech is better.
[...] If somebody has to place their iPhone or whichever device precisely on a charging mat, then what's the difference between that and just sticking a damn cable into your phone?
The cable requires a port. Apple hates ports.
How... Apple did not remove “the port” after implementing that coil. Simply because a port’s primary purpose is data exchange and the Lightning port is needed for example to record iPad/iPhone screen or to attach external storage. You may need to record the iPhone/iPad's screen to enhance the quality of a low resolution movie you can't do without, for example, by applying filters and downsizing afterwards.
As inefficient as these charging mats are, I was surprised they ever wanted to get into this market to begin with.
To be honest, maybe I was naive, but when I first heard about wireless charging, I thought it would be charging where you could have your iPhone or whatever across the room and it would charge even if the base was located in the corner of the room. That sounds pretty convenient.
If somebody has to place their iPhone or whichever device precisely on a charging mat, then what's the difference between that and just sticking a damn cable into your phone?
I don't see the appeal in wireless charging, especially not for the added cost that it requires. I'm not seeing the benefit of it yet, but that's just my opinion.
Three devices, one cable. Toss it in your travel bag and you’re set. At home plug it in on the kitchen counter where we already drop our devices. The value in these use cases is obvious. Don’t quit your day job.
As inefficient as these charging mats are, I was surprised they ever wanted to get into this market to begin with.
To be honest, maybe I was naive, but when I first heard about wireless charging, I thought it would be charging where you could have your iPhone or whatever across the room and it would charge even if the base was located in the corner of the room. That sounds pretty convenient.
If somebody has to place their iPhone or whichever device precisely on a charging mat, then what's the difference between that and just sticking a damn cable into your phone?
I don't see the appeal in wireless charging, especially not for the added cost that it requires. I'm not seeing the benefit of it yet, but that's just my opinion.
Three devices, one cable. Toss it in your travel bag and you’re set. At home plug it in on the kitchen counter where we already drop our devices. The value in these use cases is obvious. Don’t quit your day job.
Three devices, one cable, and some large pad contraption that you also have to bring along if you travel?
And what about if you travel and bring iPads and laptops? Those would need their own regular adapter I would assume, since they need more power.
A small charger with multiple wires seems to be a lot smaller in size than one large pad with one wire, which won't even charge something like an iPad.
But to each their own. I certainly don't see any need for me to jump on any wireless bandwagon at this present time.
Do you act like this in real life? Would you present a reasoned argument to a client then sum it up with "Don't quit your day job?" If not, why do you do it here?
I just can't fathom why you and a few others find it necessary to insult those who don't share your point of view. Your otherwise perfectly valid point is obscured by you choosing to deliver it covered in shit.
Knock it off. It's cowardly, rude, and discourages others from sharing what might be enlightening observations.
As inefficient as these charging mats are, I was surprised they ever wanted to get into this market to begin with.
To be honest, maybe I was naive, but when I first heard about wireless charging, I thought it would be charging where you could have your iPhone or whatever across the room and it would charge even if the base was located in the corner of the room. That sounds pretty convenient.
If somebody has to place their iPhone or whichever device precisely on a charging mat, then what's the difference between that and just sticking a damn cable into your phone?
I don't see the appeal in wireless charging, especially not for the added cost that it requires. I'm not seeing the benefit of it yet, but that's just my opinion.
Three devices, one cable. Toss it in your travel bag and you’re set. At home plug it in on the kitchen counter where we already drop our devices. The value in these use cases is obvious. Don’t quit your day job.
Three devices, one cable, and some large pad contraption that you also have to bring along if you travel?
And what about if you travel and bring iPads and laptops? Those would need their own regular adapter I would assume, since they need more power.
A small charger with multiple wires seems to be a lot smaller in size than one large pad with one wire, which won't even charge something like an iPad.
But to each their own. I certainly don't see any need for me to jump on any wireless bandwagon at this present time.
Agreed. Any first generation AirPower device would not make a good travel companion.
It would have been a nice convenience option at home but wholly inefficient in terms of speed, size and wasted energy for any travelling.
As you say, a single adapter with the correct cables would be a far better option and if you happen to travel to a smart city you will be able to charge pretty much anywhere.
to provide high power charging. I counted 15 charging points on a bus the other day. There are also charging points in shopping centres, toilets, restaurants, gyms etc and of course all hotels.
I live in a small town but even we have intelligent defibrillators in the street, LED powered street lamps (with connections built in for Christmas street lighting!) etc.
At some point public Qi wireless panels will become more popular but until then I think carrying a large charging pad around won't be all that commonplace.
Yes, it is a ridiculous world we live in when real-life engineering problems make my entitlement to consumer goods secondary. Don't they know who I am??
How immature. No need to be so aggressive. It’s ridiculous Apple announced a product as early as they did. There’s nothing entitlement related to that at all.
Yes, it is a ridiculous world we live in when real-life engineering problems make my entitlement to consumer goods secondary. Don't they know who I am??
That’s a strangely personalised attack.
The probjrm here for Apple was the early announcement. Be interesting to know who pushed that.
It's not a personal attack, or aggressive, or immature, in the slightest. I pointed out the bizarre position that feeling entitled to the product makes the real-life engineering failure "ridiculous". It doesn't. These are not easy feats, despite how magical they seem to use.
I understood your point. Thought it was funny the way you put it. Whether he was giving lip service or not I appreciated that the Apple exec said it (AirPower) wasn’t up to company’s standards.
Certainly it’s disappointing, but:
A. I’m way happier with them cancelling it than with shipping a product that could become dangerous due to overheating or other quality issues;
B. I strongly suspect the technology they were working on and the lessons learned from this failure will — as has happened a number of times in the past — be put to future good use, starting with “don’t pre-announce products so far ahead”;
C. I’m much consoled by the fact that nearly all of the haters complaining about this cancellation above would be tearing the company a new one when they saw the price of the AirPower. It was likely going to be 4x more (at least) than a standard Qi charging pad, and at least double or even triple the price of the deluxe models (dozens of which are already out there) that can charge all three devices at once, but you have to place them more precisely on the mat (gasp! shock! outrage!) than you would have with the AirPower. Some of you guys are great, but most of you need to face the reality that you’re terrible hypocrites.
In fact, I’d bet that in the end they actually had the technical problems mostly or entirely licked — but the thing would cost north of $300 due to the precision manufacturing and high technology required (you know, same reason we haven’t seen any $35,000 Model 3 Teslas, either).
You knocked it out of the ball park my friend. Well said.
So it was always ever vaporware. Nice going, Apple.
I think you should do a little homework so you can understand what Vaporware truly is. Obviously you don't.
Apparently, nor do you. "Vapourware: noun Computing, informal. Software or hardware that has been advertised but is not yet available to buy, either because it is only a concept or because it is still being written or designed."
Alright fair enough, but the term generally is used in regards to companies at CES who only show concepts and announce that the product will be available in the coming months of the same year, but are never talked about any further for several years. It's usually to create hype. I don't see where Apple qualifies under this situation.
Fairly sure Apple announced AirPower in 2017, promised it in 2018, and didn't talk about it any further for several years, until its cancellation today.
Rumors speculated that Apple was considering up to 32 coils—up from the fifteen shown in their conceptual patent filing.
We asked an engineer with experience building wireless charging systems what obstacles Apple was working to overcome. “Over time, these harmonics add up and they become really powerful signals in the air,” explains William Lumpkins, VP of Engineering at O & S Services. “And that can be difficult—that can stop someone’s pacemaker if it’s too high of a level. Or it could short circuit someone’s hearing aid.” If Apple’s multi-coil layout was spinning off harmonics left and right, it’s possible AirPower couldn’t pass muster with US or EU regulations."
I don't know why they wouldn't just settle for a 3-6 coil charger and put markings on the top where the products should go. The mat could even have made a bleep noise like the iPhone when it successfully connected. This is just a charger for the iPhone, Watch and AirPods. It doesn't need to have 32 coils, just 1 for each product. There's one here with 5 coils plus 1 for the Watch:
Products like these are useful to have for guests charging devices. It's unlikely that you'd leave charging cables lying around but charging mats can be left on guest tables. Hotels in other countries can have these fixed to hotel room tables so that people don't have to worry if they forget to take the right adaptor or bring enough cables for each product.
It's no big loss for Apple not to make one when 3rd parties will offer them, similar to routers but their products don't have to be ground-breaking to be justifiable.
I'd still prefer to see a low power (<1W) wireless solution like wifi. AirPods only have a 1.5Wh battery. Have a wifi-like router transmit something like 0.5W per device through directed waves and AirPod cases and Watches can charge while sitting around anywhere. iPhones would take a while to charge fully but even if they can charge 50% while in someone's pocket or bag during a working day, it's less time connected to a wall socket.
Rumors speculated that Apple was considering up to 32 coils—up from the fifteen shown in their conceptual patent filing.
We asked an engineer with experience building wireless charging systems what obstacles Apple was working to overcome. “Over time, these harmonics add up and they become really powerful signals in the air,” explains William Lumpkins, VP of Engineering at O & S Services. “And that can be difficult—that can stop someone’s pacemaker if it’s too high of a level. Or it could short circuit someone’s hearing aid.” If Apple’s multi-coil layout was spinning off harmonics left and right, it’s possible AirPower couldn’t pass muster with US or EU regulations."
I don't know why they wouldn't just settle for a 3-6 coil charger and put markings on the top where the products should go. The mat could even have made a bleep noise like the iPhone when it successfully connected. This is just a charger for the iPhone, Watch and AirPods. It doesn't need to have 32 coils, just 1 for each product. There's one here with 5 coils plus 1 for the Watch:
Products like these are useful to have for guests charging devices. It's unlikely that you'd leave charging cables lying around but charging mats can be left on guest tables. Hotels in other countries can have these fixed to hotel room tables so that people don't have to worry if they forget to take the right adaptor or bring enough cables for each product.
It's no big loss for Apple not to make one when 3rd parties will offer them, similar to routers but their products don't have to be ground-breaking to be justifiable.
I'd still prefer to see a low power (<1W) wireless solution like wifi. AirPods only have a 1.5Wh battery. Have a wifi-like router transmit something like 0.5W per device through directed waves and AirPod cases and Watches can charge while sitting around anywhere. iPhones would take a while to charge fully but even if they can charge 50% while in someone's pocket or bag during a working day, it's less time connected to a wall socket.
Well, I must say that Kickstarter product looks terrible.
It would have been nice to announce this cancellation before announcing AirPods with a wireless charging feature. I feel like I spent $40 that I did not need to on something that Apple has decided not to support. Weak.
I'd still prefer to see a low power (<1W) wireless solution like wifi. AirPods only have a 1.5Wh battery. Have a wifi-like router transmit something like 0.5W per device through directed waves and AirPod cases and Watches can charge while sitting around anywhere.
Not sure I’m keen on the idea of actual power passing through my brain along with all those radio waves...
I'd still prefer to see a low power (<1W) wireless solution like wifi. AirPods only have a 1.5Wh battery. Have a wifi-like router transmit something like 0.5W per device through directed waves and AirPod cases and Watches can charge while sitting around anywhere.
Not sure I’m keen on the idea of actual power passing through my brain along with all those radio waves...
The power levels Marvin mentioned mean you don't have to worry. Your phone's transmitter is three times as powerful as what he's describing. Plus the risk depends as much on the frequency at which the signal is transmitted as the power.
Plus, and this is the big one, your body is able to tolerate all kinds of invisible radiation thanks to evolving on a planet that's inundated with it. If you removed every single human-made source of RF and EM, there would still be a ton of it emanating from the sun, other sources in space, and the Earth itself.
Comments
If somebody has to place their iPhone or whichever device precisely on a charging mat, then what's the difference between that and just sticking a damn cable into your phone?
I don't see the appeal in wireless charging, especially not for the added cost that it requires. I'm not seeing the benefit of it yet, but that's just my opinion.
It was "several years" on Mercury, a couple years on Venus, but only a year and a half here.
This fixation on Apple needing to "innovate" is mind-boggling. What defines innovation? If their iPhones look different from one generation to the next, suddenly it's innovation? Apple invests HEAVILY in technology that you can't see! That's where the innovation is. So what if the outer appearance of the device looks the same... as long as they've moved the game forward inside and it's a better device for it. And that's been the case, year after year after year. Macs may have slipped slightly in the regular updates, but I think they are getting themselves back on track. I think the move to their new campus was a huge distraction, which is now behind us.
Innovation is also not having the fastest processor or the highest-megapixel camera. None of that matters if the devices as a whole performs poorly, and Apple excels at delivering devices that perform exceptionally with half the resources of the competition, yet continue to set the lead for processor performance.
So I don't think there's any reason to be concerned about Apple caring about tech. The only problem was a slowdown in Mac updates. But they are now caught up.
And innovation costs money, so we can't have our cake and eat it, too. You either get innovation or your get cheap (-ly made) products, not both. Apple products are expensive for a reason. We all hate it, but it's not pure greediness. The tech is better.
And what about if you travel and bring iPads and laptops? Those would need their own regular adapter I would assume, since they need more power.
A small charger with multiple wires seems to be a lot smaller in size than one large pad with one wire, which won't even charge something like an iPad.
But to each their own. I certainly don't see any need for me to jump on any wireless bandwagon at this present time.
I just can't fathom why you and a few others find it necessary to insult those who don't share your point of view. Your otherwise perfectly valid point is obscured by you choosing to deliver it covered in shit.
Knock it off. It's cowardly, rude, and discourages others from sharing what might be enlightening observations.
It would have been a nice convenience option at home but wholly inefficient in terms of speed, size and wasted energy for any travelling.
As you say, a single adapter with the correct cables would be a far better option and if you happen to travel to a smart city you will be able to charge pretty much anywhere.
Barcelona Metropolitan Transport uses YupCharge
https://www.yupcharge.com/en/
to provide high power charging. I counted 15 charging points on a bus the other day. There are also charging points in shopping centres, toilets, restaurants, gyms etc and of course all hotels.
I live in a small town but even we have intelligent defibrillators in the street, LED powered street lamps (with connections built in for Christmas street lighting!) etc.
At some point public Qi wireless panels will become more popular but until then I think carrying a large charging pad around won't be all that commonplace.
https://www.kickstarter.com/projects/2127998328/slicecharge-pro-worlds-1st-6-coils-wireless-chargi
Products like these are useful to have for guests charging devices. It's unlikely that you'd leave charging cables lying around but charging mats can be left on guest tables. Hotels in other countries can have these fixed to hotel room tables so that people don't have to worry if they forget to take the right adaptor or bring enough cables for each product.
It's no big loss for Apple not to make one when 3rd parties will offer them, similar to routers but their products don't have to be ground-breaking to be justifiable.
I'd still prefer to see a low power (<1W) wireless solution like wifi. AirPods only have a 1.5Wh battery. Have a wifi-like router transmit something like 0.5W per device through directed waves and AirPod cases and Watches can charge while sitting around anywhere. iPhones would take a while to charge fully but even if they can charge 50% while in someone's pocket or bag during a working day, it's less time connected to a wall socket.
Apple cancels AirPower wireless charging mat, citing quality issues
Or
Apple has dropped the axe on the AirPower mat, for reasons as of yet unknown, and will not produce the device
Plus, and this is the big one, your body is able to tolerate all kinds of invisible radiation thanks to evolving on a planet that's inundated with it. If you removed every single human-made source of RF and EM, there would still be a ton of it emanating from the sun, other sources in space, and the Earth itself.