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Harvesting Wi-Fi Backscatter To Power Internet of Things Sensors
vinces99 (2792707) writes "Imagine a world in which your wristwatch or other wearable device communicates directly with your online profiles, storing information about your daily activities where you can best access it – all without requiring batteries. Or, battery-free sensors embedded around your home that could track minute-by-minute temperature changes and send that information to your thermostat to help conserve energy. This not-so-distant 'Internet of Things' reality would extend connectivity to perhaps billions of devices. Sensors could be embedded in everyday objects to help monitor and track everything from the structural safety of bridges to the health of your heart. But having a way to cheaply power and connect these devices to the Internet has kept this from taking off. Now, University of Washington engineers have designed a new communication system that uses radio frequency signals as a power source and reuses existing Wi-Fi infrastructure to provide Internet connectivity to these devices. Called Wi-Fi backscatter, this technology is the first that can connect battery-free devices to Wi-Fi infrastructure. The researchers will publish their results at the Association for Computing Machinery's Special Interest Group on Data Communication's annual conference this month in Chicago. The team also plans to start a company based on the technology.
The Pre-print research paper.
And now a word from our sponsors, the NSA. Oops, I mean look a distraction.
Don't waste your vote! Vote for whoever you want, unless you live in a swing state it won't matter anyways
I can't believe they're actually advocating for RF pollution as a way to power things.
Powered by radio waves.
Correct me if I'm wrong, but didn't Tesla say wireless charging like this was impossible?
I mean I hate "Internet of Things". Stupid term created by stupid people for stupid people.
...is new again:
http://en.wikipedia.org/wiki/The_Great_Seal_bug
Nice to see the idea being put to a less nefarious use. :)
I have no idea what they said, but it's trivial to get power from radio waves. It's easy to build your own circuit to do so.
https://www.google.com/webhp?sourceid=chrome-instant&rlz=1C1RQEB_enUS598US598&ion=1&espv=2&ie=UTF-8#q=crystal%20radio%20circuit%20diagram
It's a matter of how much power you can harvest. An earphone uses a few microwatts of power whereas a car motor uses kilowatts. 9 orders if magnitude difference. 1,000,000,000x
This sounds just what iFind was promising before they were suspended from kickstarter
Remember throwies? Magnet+battery+LED. Throw it up on exposed steel beams, water towers, stainless trim, etc. Mostly a harmless prank except that somebody eventually has to remove them to avoid permanent marks on surfaces due to weathering. I can't help but picturing "lighting up" their networks with a bunch of throwies. Cheap Solar Cel + ID Chip = a neighborhood with a much different appliance profile than they think. Refrigerators in the garden, all needing milk. Blenders up a tree. Microwaves in the bushes. Not as amusing for passers-by as LEDs on buildings; but maybe it might teach somebody a lesson.
Didn't we just have this argument, like, a month ago?
Sure, the term is a bit stupid, but the technology and the intent aren't.
So, what it boils down to is this: are you going to get hung up on a rather silly term, or are you going to realize that it's just a term and that the term makes not slightest bit of difference to the physical reality of the devices?
Since you don't like "stupid", I suggest that you don't act stupid --- don't get hung up on a phrase.
They're talking about very short ranges, like under 2 meters. This may not be too useful.
What we need in wireless power is for the inductive charging pad industry to get their act together. There are at least three competing standards (QI, PMA, and WiPower/Rezence), so they're not widely used. Last February, the PMA and WiPower groups agreed to develop multi-mode charging pads that will power both PMA and Rezence devices. Then there are some Samsung devices that will charge from either a Qi or a Rezence pad, but not a PMA pad.
but thank you anyway.
... when there's much more energy in light or heat?
Solar cells power calculators and garden lights pretty well. Domestic lights put out 5-100 watts of power distributed around a room.
Wifi power levels are much lower - 0.15 watts or so.
Andrew Yeomans
Oh great. You take a walk during lunch because you're concerned about your health. You stop to re-tie your shoe. Too bad your watch tattled that you just paused in front of a 'bookstore' that sells gay porn.
Suddenly you get spammed with offers for gay porn. It's also too bad your employer was exempted from EOE because it's against the corporation's sincerely held religion, so you get fired in the process.
Sadly for you, as you take that long walk back to your parking space you pause a gain (you'll never learn!) next to a fast food joint. By the time you get home you have an e-mail informing you of the increase in your health insurance premium.
The internet of things could be interesting if those things would report to a server that I own and control. Too bad most corporations make internet enabled things report to them so they can sell your personal information to the highest bidder with no questions asked.
Won't this just put a greater load on the Wifi transmitters, or dampen the signal ?
All great comments from the tinfoil hat folk ;), but just look at the practicality of all this. It still is a long way of.
What they do, is in effect the same mechanism they use to detect planets if far away solar systems. Because the light from that sun dimms only slightly (because the planet deflects/absorbs the light), they can detect a planet (or at least, they hope so). So they did this in a lab for the RF and so called "internet of things" devices, and were able to have a whopping range of up to 65 cm, communicating by fluctuating the signal strength of the wifi signal to morse code data, just like they use the light pattern coming from the star te determine the size and orbital period of the planet). WOW! Obviously, there are a lot of things wrong with this. Cranking the range up will be massively difficult for one. What about when multiple devices do this: I thinks it will be extremely difficult to keep them apart. Also, just being able to communicate, does not make it a useful thing. Mostly you'll need power to sense or act. This has to come from somewhere, too.
I'd say this is still years from being a commercially viable product, if at all.
It (hopefully) tends to be more energetic.
BTW Europe does pretty well regarding saving heating by using insulation and a couple of stratetically placed sensors (outdoor, indoor temp, heating circuit outgoing, heating circuit back) coupled with a real programmable heating control unit (insulation levels, night programm, backoff, etc). Thermal efficiency of around 92% is not uncommon.
This simple example show that we don't need crazy complex stuff.
Can you ...
...Imagine a world in which your wristwatch or other wearable device communicates directly with your online profiles, storing information about your daily activities where you can best access it â" all without requiring batteries.
All to well, I'm afraid. What I can't imagine is what the hell I or anybody else would want that? I'm not much of a Luddite, but being constantly online is just not part of my lifestyle, and seeing the quality of the online natterdom, I feel no attraction at all, on the contrary. It's just like having a million TV channels, all of them showing Big Brother and Coronation Street and nothing else, 24/7.
We need to build tin foil suits. The hat is just not going to do it for us anymore. Pass me the roll.
Once again the 'E' word and the 'F' word is missing - encryption and firewall. Putting something on the internet is not practical if it can't support encryption and a firewall.
Technically, the device would need to harvest power from 2.4GHz RF and then use that power to power its own transceiver and CPU. Sorry, but I don't see this happen. Harvested RF may be in the order of microwatts. How on earth is this going to power anything besides maybe, a very low dutycyle / long period beacon of some sort? It's just not plausible.
I will continue to call the phrase "Internet of Things" stupid, for as long as you continue to hype it.
The battle of pointless endurance is mine!
Of course it has nothing to do with cost, uselessness, or invasion of privacy. People are just waiting for this technology in Bumfuck Nowhere like they've been waiting for "home automation" all these years.
*LMAO*
I do not fail; I succeed at finding out what does not work.
Have gnu, will travel.
"Imagine a world in which your wristwatch or other wearable device communicates directly with your online profiles, storing information about your daily activities where you can best access it â€" all without requiring batteries."
Because I certainly don't feel comforted by it.....
Donald Trump, on a crusade to make Nixon look respectable
Inforwars called. They said all of ya are at the wrong website.
The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
Take a look at how RFID chips have worked since day one - they use the incident RF to power the chip that then back-modulates the transmitted signal. In other words, the RFID tag actively modulates the load impedance it places on the antenna causing changes in the radar cross-section of the tag. The tag transceiver sees these variations in cross section as data from the tag.
Tiller's Rule: Never use a word in written form that you've only heard and never read. You will end up looking foolish.
Will it power the rfid tag embedded in my skull? I demand to be tracked constantly by always on devices embedded in my skull or ingested so that I can share all the gross details on facebook and with our very own intelligence services. You can never know enough about your social and bodily habits!
Must be a wet dream for NSA
Gathering power from RF is not new. This might be a novel way to implement it, but it will have the same issues.
1) No free ride. Taking RF and turning it into electricity means less range for the RF.
2) You are still paying for power. No it's just a lot less efficient.
There is a reason the radio industry has worked hard to stop RF power light bulbs. Because the broadcaster would be paying for your electricity.
The Kruger Dunning explains most post on
"Imagine a world in which your wristwatch or other wearable device communicates directly with your online profiles, storing information about your daily activities where you can best access it..."
My friends don't need to know about my wrist's daily life. Adding sensors for heart rate, glucose level, and so on would make me even less inclined to want my wrist to be ratting me out constantly to Facebook.
Call me a curmudgeon, but I see all this wearable tech crap as a passing fad at best, and more likely just a load of baseless hype.
Write me an app that lets me spend more time with my kid, or get to a campground more often and we can talk. More gadgets to clutter my already hectic life just has no appeal to me.
Do you want a Samsung Android backdoor in your refrigerator, your gym shoes, your thermostat, your clothes hamper?
What the fuck people? Seriously. This is fake convenience, pushed to micro-monitize every minor detail of your lives - bad enough.
That entails micro-monitoring of where you are walking, how much milk you drink, what you say when you can't find something in the bathroom, how long you pant after taking out the garbage, how many times you have to say goodnight to your kids before they sleep, how many days you go between masturbating, how frequently this occurs after viewing a particular FaceBook profile...
All to run a fucking gas-meter on your life - ticking it out, pennies at a time for the benefit of parasitical middle-men in some dubious "value chain".
Then? There are the "Agencies" and it doesn't take tin-foil to go this direction, after Snowden.
SAY NO. NO INTERNET OF THINGS.
"Flyin' in just a sweet place,
Never been known to fail..."
Seems like every time someone says "not possible" here, someone eventually proves them wrong.
So, violating the laws of gravity is going to be possible someday? Something tells me that Newton's laws are safe... So I think your whole argument just came crashing down.... (Yea, Ok.. Not that funny but I tried...)
"File to fit, pound to insert, paint to match" - Aircraft Maintenance 101
Imagine a world in which your wristwatch or other wearable device communicates directly with your online profiles, storing information about your daily activities where you can best access it
This must be an early April fools joke.
. Sensors could be embedded in everyday objects to help monitor and track everything from the structural safety of bridges to the health of your heart
Who thinks it is a good idea for sensors monitoring "structural safety" to be harvesting energy from WiFi signals?
battery-free sensors embedded around your home that could track minute-by-minute temperature changes and send that information to your thermostat to help conserve energy.
Unless your using resistive heating (most wasteful way to heat a home imaginable) no complex array of sensors is going to conserve anything worth measuring compared with a simple PID loop and properly sized forced air system.
Imagine a world in which your wristwatch or other wearable device communicates directly with your online profiles, storing information about your daily activities where you can best access it – all without requiring batteries.
Even if it doesn't require batteries, why would I want to have an online profile updated with what I've shat today?
I apologize for the lack of a signature.
Hmmm, I think that has practical applications.
The following are impossible: FTL, strong AI, Mr. Fusion, routine interplanetary spaceflight, and a thoroughly usable Slashdot Beta.
"When you have eliminated the unacceptable, whatever is left, however improbable, must be the truthiness" - Holmes