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Mass Market Hopes For Battery-free Cell Phone Technology (reuters.com)
Mark Hanrahan, writing for Reuters: Researchers in the United States have unveiled a prototype of a battery-free mobile phone, using technology they hope will eventually come to be integrated into mass-market products. The phone is the work of a group of researchers at the University of Washington in Seattle and works by harvesting tiny amounts of power from radio signals, known as radio frequency or 'RF' waves. "Ambient RF waves are all around us so, as an example, your FM station broadcasts radio waves, your AM stations do that, your TV stations, your cellphone towers. They all are transmitting RF waves," team member Vamsi Talla told Reuters. The phone is a first prototype and its operation is basic - at first glance it looks little more than a circuit board with a few parts attached and the caller must wear headphones and press a button to switch between talking and listening.
Interesting article on bit coins. Now what about this battery free phone?
Nikola Tesla's life obsession was wireless transmission of electrical power. A company that actually makes devices running on wireless power should be called Tesla!
He didn't give a shit about battery powered cars btw
...is also sending RF. Indeed we're drowning in it.
They created self winding watches, can't they make self winding cell phone?
The iPhone 8 will have no battery and Apple will claim it took 'courage' to remove it. From now on, the user will need to remain within 10 feet of a compatible iCharge wireless power adapter.
While people don't like to charge their Smartphones, they don't want to give up their Whatsapp and their big screens either.
What this might revolutionize, maybe, is the Internet of Shi^WThings. Tiny sensors with attached cell phone modem that phones home the sensor data to a central location. if one can power this from ambient RF noise, that would be awesome and really a billion dollar market.
Before anyone dismisses this outright, please read up on how a crystal radio works.
https://en.wikipedia.org/wiki/...
https://en.wikipedia.org/wiki/...
If you post as Anonymous Coward, don't expect a reply.
I'm not particularly worried about RF radiation affecting my health, but how can ubiquitous RF radiation possibly be strong enough to power a smartphone, while being so weak that it can't possibly affect our health?
Please don't make me have to start walking around in a faraday cage again.
You are welcome on my lawn.
Back in my day we bought the most expensive phones we could! and they were damned slippery too! why, just one errant flick of the wrist you'd destroy an entire paycheck or more of the most advanced, encumbered, and contractually obligated silicon you'd ever set your eyes upon! And the government spied on us all the time and lied to us about it...and we liked it that way!!
now you damned millenials want to take the battery out? how will my phone swell menacingly over the years due to shoddy manufacturing processes? Back in my day we used to throw parties to celebrate whoevers phone blew up first. Dorris in accounting lost a damn leg from her Samsung but ill tell you one thing...nobody in the office would forget those fireworks! and think of THE CHILDREN! you know, the ones that make these phones and enjoy constant exposure to the byproducts of battery manufacturing. And what about charging?? Back in my day we used to charge all day every day until the battery went bad, then we'd buy more phones! its like you kids dont even understand how fun it is to buy a new phone every year or something.
Good people go to bed earlier.
I realize this particular Reuters article may be new; but haven't we seen stories about this exact same research project several times already over the past couple of months?
#DeleteChrome
If this was the article from a few days ago, the device in question harvests RF power from a transmitter within 30 or so feet of the device and transmits back to that same device.
Given the 30ft range it is unlikely to be useful for much of anything, and probably does not have close to enough power to even deliver audio to a person to be a viable basic phone. And it is not as if the physics are going to work (harvesting enough device even for basis audio usage is pretty much impossible, unless there is significant amounts of RF running around).
I wonder if this battery-free cell phone from the University of Washington is anything like the battery-free cell phone from the University of Washington last month?
https://mobile.slashdot.org/st...
Correct me if I'm mistaken, but isn't tuning into an RF freq essentially just a form of induction. Meaning, the moment you tune into that frequency, the minute energy captured is also putting a load on the transmitter. So, if everyone in a city tuned into an AM radio station at the same time, there would be a significant draw on the antenna until people tuned off the channel. If so, the energy isn't "free" in a since of being ambient; somebody is paying for that electricity.
Life is not for the lazy.
Since the article points to something about bitcoins, I can't readily respond to the specifics, but stuff like this has been around a while. You can even find cheap little kits on eBay that power an LED from GSM RF, although those don't work very well in the states. And there are the classic crystal radio kits that have no battery at all.
The most important thing to develop for something like this is ultra low-power technology, like displays and CPUs that run on less than a microvolt and antennas that can transmit and receive low power signals over long distances. In which case a modern battery could run a cell phone for years on a single charge (or be replaced with a much smaller battery). Which begs the question, why bother with a battery-less device with all the components (read: cost) that would need to go into it to harness electricity from RF when you can just plug in a battery that'll run for years? I don't think you would. I think this is more novelty than something for mass-market.
I hope to be proven wrong.
Does solar count as RF power? Since radio and light are both EM radiation...
Some people didn't pass.
Some schools passed people who absolutely didn't deserve it.
That's the only logical explanation that I can see for this story appearing on Slashdot today.
NYT Link: https://www.nytimes.com/reuter...
Research web site: http://batteryfreephone.cs.was...
Research paper: https://homes.cs.washington.ed...
The interesting aspect is that, given that most people text more than they call, the power requirements for the cell call drop when you use methods like that, making some of the related work on clothing to incorporate cell elements tie in. Basically, Star Trek comm badges become highly viable, using incident work/home power from wi-fi and TV sets, and you can set up common areas to have higher levels of broadcast power (elevator lobbies, conference areas) for actual voice and video calls.
The future is now. The fact that you remain in denial of it is not our problem.
You can even power these by window solar biofilms, which radiate the power inside, or flexible solar printed wraps. So you could do handsfree calls even when riding a bike or while skateboarding. Without bulky batteries.
-- Tigger warning: This post may contain tiggers! --
at first glance it looks little more than a circuit board with a few parts attached and the caller must wear headphones and press a button to switch between talking and listening
This was on /. within the last three months.
Also, judging by the description above it's not a phone, it's a walkie talkie.
I hope for magic unicorns
... turning a generator will power it indefinitely, so long as I keep turning it. No battery required.
The problem here is cell phones transmit back to a tower regularly, which requires more power than can be drawn from the air. For that you need either a really big ultracapacitor, or ... a battery. Either that or you can go about your day turning a crank for the generator on your phone.
So it's able to harvest enough power from radio signals to power the phone *in real time*? Including the screen?
I could understand a technology like this being used to *charge* phones, passively, but they would still require a battery. What happens if you momentarily enter a shielded area that radio waves cannot penetrate? Your phone just instantly dies? That would be terrible.
I *really* hope this is just marketing idiocy, and there is, in fact, a battery incorporated into the design of these devices.
There is about a 140 decibel gap between the amount of energy you can receive and the amount you need to transmit. My iPhone right now is receiving about -110dBm. To transmit at 1 watt, it needs about +33dBm. That's 140 decibels, or 10^14. Even if you lived in a very RF-rich environment, that only shrinks the gap by say a factor of 1000, you are still 100,000,000,000 times short on power. Not gonna work.
So it's able to harvest enough power from radio signals to power the phone *in real time*? Including the screen?
I could understand a technology like this being used to *charge* phones, passively, but they would still require a battery. What happens if you momentarily enter a shielded area that radio waves cannot penetrate? Your phone just instantly dies? That would be terrible.
I *really* hope this is just marketing idiocy, and there is, in fact, a battery incorporated into the design of these devices.
What screen? This isn't a smart phone, it's a very, VERY basic cell phone. No screen included: http://batteryfreephone.cs.washington.edu/
I browse on +1 so AC's need not respond, I won't see it.
This is a rather old idea, but I'm not aware of anyone doing it with modern hardware. You can't actually draw that much power through ambient radio waves, though. In the past, it's never been more than a curiosity because you couldn't build devices that could do anything useful with the amount of power you could get -- but these days, you can build useful circuits that need a whole lot less. This will be interesting to watch.
The first thing that popped into my mind when reading the title was the Heechee novels by Frederik Pohl. They were an alien species that required low-level microwave background energy to maintain body warmth, and to power the 'old ones', digitally(?) preserved brain images of the deceased.
I've often wondered when the level of background radiation was going to become high enough to allow devices to 'capture' this background flux and use it to power low-power devices.
OK, so it smacks of the 'TESLA' radiated energy schemes, still - it's everywhere in industrialized areas of the world, and it was only a matter of time before the flux density became high enough to be scavenged and put to use powering small, low-power devices.
redneck geek
If these cell phones become ubiquitous it will play havoc with broadcast radio and TV signals, as well as public safety radios. Millions of phones harvesting radio waves won't leave any signal for legitimate receivers. In fact the very signals these phones need to receive to provide communication will be disrupted. This is a bad idea.
There are much more appliances that would benefit a lot from this kind of technology, like remote controls, wall clocks, wristwatches (non/lightly smart), e-readers, all kind of sensors, etc.
Seems more like a battery free walkie talkie. Also, while I can understand how you can recieve with no battery (using old school crystal radio technology) the ability to transmit using no power is quite a surprise.
I read the internet for the articles.
Why don't they just plug an outlet strip into itself, then plug the phone charger into that? Infinte power! xD xD xD
That's what this reminds me of: Troll Physics memes.
RF power is no way close to powering your cell phone even 30 min a day of basic operation of talk time. Solar phone covers are already existing and works pretty well.
....an article, I believe from Byte Magazine, about micro tesla coils on a chip that too advantage of all the latent ratio signals that always are around us. About time someone figured out how to actually implement a device that can turn these radio waves into useful energy to power up devices. :)
Imagine how long one of these will last with a battery! The problem is not with the capacity of batteries - the problem is with how many things a modern phone is asked to be.
How many "battery breakthroughs" announced in Slashdot over the years have ever made it to the masses? One in fifty? One in a hundred? None/
You wouldn't need a battery. An ultracapacitor would store the gathered energy just fine.
Crystal radio is so weak because it only uses rf that contains the signal. more modern devices have the entire EM spectrum to feed upon.
Yeah this particular device is short sighted. We should be building devices that graze on the entire EM spectrum
I built a crystal radio when I was 6. It also required the user to wear a mono earpiece. https://en.wikipedia.org/wiki/... I guess my 6 year old self was smarter than the researchers they have at the University of Washington.
This device operates 10-15 m away from the base station. A regular cell phone won't even work at that distance, its receiver being saturated.
Depending on base station power and antenna gain it may be unsafe for a human to stay too long in that area.
This really isn't a phone, because what they forget to mention is that this is actually nothing more than the 'receiver' (as in microphone/headphone), it has a basestation that does the actual digitizing and has the rest of the phoneparts (it's not even to be compared to a DECT handset and it's basestation), which ofcourse drinks it's juice from the wallplug.
If this gets out then no one will be able to listen to the radio.