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Intel Encodes Data In Flickering LEDs (and Shows Off Other Bright Ideas)
darien writes "On the day before the Intel Developer Forum opens in San Francisco, Intel has been showing off some of its current research projects, including a system for encoding data in apparently steady light sources, a Kinect-based projected 'touch interface' that works on any surface and an ambitious signage concept that could revolutionise your weekly shop." My favorite thing about light-based networking is that it's the basis of a certain strain of (all too plausible, all too often) conspiracy theory. ("The modern LED 'eco-friendly' light bulb is also a two-way communications device." — easy to believe, since many of them can be. )
Imagine being an light dependent alien, coming to visit you with all your blinking communications leds all over your house.
Wow...what a mind job that would be.
What this world is coming to - is for you and me to decide.
IRDA, but without the "I".
"National Security is the chief cause of national insecurity." - Celine's First Law
Back in the old days(tm), people claimed to be able to intercept your communications from outside the building by simply having a view of your modem TX RX lights. That was in the days of the 1200 baud modem. Nothing has changed. There are still those that claim the same thing about your high-speed cable modem.
Wha... encoding digital data at a rate faster than the flicker response of the human eye? Is that even legal? OMG what a breakthrough. Next thing you know, someone will figure out how to encode stereo information in a high-frequency side-band to the mono signal.
https://app.box.com/WitthoftResume Code: https://github.com/cellocgw
encoding data in apparently steady light sources
This is the "new" part. Not hard, but new. Usually you design a modulation method to minimize total power, usually you don't care about DC balance or constant power output unless there's something weird going on with the AGC ckt of the receiver.
The new part isn't so much reinventing something like manchester encoding, but considering its constant long term average power the primary feature.
I would think simple FSK would be reasonably constant power as long as LED device capacitance or lead inductance isn't distorting the signal (giving it a tilt)
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
He said to the king, you will now be able to spread your words to all.
Then a year later, the king comes back complaining about how everybody else is writing about him.
I swear, they write the summaries in a deliberate attempt to induce nerd rage.
LEDs on some devices leak data. This is not a conspiracy theory. There have been proof of concept attacks staged against real, commercially built devices that are in production. http://news.cnet.com/2100-1001-854946.html
Also, the idea of using visible light to transmit data is not new. It's just not really useful for anything, compared to the other available methods.
I think someone posted this TED talk here some time ago: http://www.smartplanet.com/blog/business-brains/wireless-data-can-be-delivered-by-led-lights-anywhere-call-it-8216li-fi/18180
I read the full article, I have to say, I was a bit disappointed. Nothing really of interest. The LED encoding has been done, before, and better. The "Display without Borders" has also been done, before, and much better. And the digital signage was a gimmick. Even as a prototype, it's silly. Yes, you took 18 androids, put them in cases, and glued them to a display rack. Presto, digital signage. Please....
I find it more interesting to read up on the research.microsoft.com projects, or MIT Media lab.
-Malakai
A Dragon Lives in my Garage
Since most traffic lights now use LEDs, this flicker-comm technology might be a good way to send info to intelligent cars about the traffic light timing, traffic conditions on the road ahead, etc.
a system for encoding data in apparently steady light sources
You mean Intel has finally invented IrDA (but with visible light - VDA?)? I can't wait for that technology to trickle down to laptops, I bet I can use it to sync my computer with my Palm Pilot.
"The modern LED 'eco-friendly' light bulb is also a two-way communications device."
At least it's a progress over incandescent lamps, actually heaters which happen to emit a little light.
High powered LED flashlights of the Luxeon, Fenix and Inforce (among others) families use timer circuits to oscillate between multiple beam elements to produce high efficiency and very bright emitters, that are capable of draining every erg from the battery.
source: I use tactical equipment. Efficiency and ruggedness is key. Keep your 5D Maglite.
The linked device is the bare LED, if you buy from that site you'll require a driver IC as well, otherwise a direct connection to a power source will cause momentary lasing before the emitter burns out. The IC prevents burnout and lasing (hence also takes the emitter out of the laser class of consumer devices).
Operation Guillotine is in effect.
This is nothing new at all. It's actually why some super-security-sensitive workplaces have strict control over even the keyboards. A keyboard modification can be made so that the scroll-lock/caps-lock/whatever-LED light actually blinks out a code for every key press. Then, any detector anywhere in the room can detect the frequency and record the keypresses, which can effectively compromise many such systems. And to the human eye, the LED blinking is too fast to detect, so it just looks like it's on.
You could read the blinking console lights to determine what the machine was doing--no need for LEDs, small incandescent bulbs were good enough.
Right.
Pricer already has 80 million shelf price label units installed. The big issues there involve cost and battery life. Display devices that draw no power when static have advantages, but most of those have a grey-on-grey look, which retailers don't like.
Sending data through lamps at 15Hz hardly seems worth the trouble. It's also likely to be annoying. Humans can see 15Hz flicker. If the amplitude is so low that humans can't see it, ambient light will interfere with reception. They can't increase the modulation rate because the input device is supposed to be a 30Hz cell phone camera.
Did Intel get these projects from their science fair program?
You mean, like virtually every grocery store in the US has been doing for ten years now?
(That's how those little digital price tags on shelves get programmed -- the lights flicker the codes down to them all day long, and slowly update the tags.)
Here is what LVX is offering: http://www.youtube.com/watch?v=m58f-XkhOjo
I don't know why Intel is getting this attention. Why not give it to LVX? Also this technology is not all that sophisticated.
I did that circa 1985 when a project did not have a suitable debug port, but had a single LED on the panel.
Excuse me, but please get off my Pennisetum Clandestinum, eh!
SOS, like this: http://lkml.indiana.edu/hypermail/linux/kernel/0302.2/0548.html
Excuse me, but please get off my Pennisetum Clandestinum, eh!
Seriously, I had one of those little radio shack electronic lab play toy thingies. Showed how to encode data via LED both visible and infrared, the infrared was a 'fiber' demo those, so you had to stick a fiber in the transmitter and receiver for the link but its really no different. The standard LED version used the red or green LED and the photoresistor right next to it as the receiver.
Its not like it was new then either. This shit is literally 30 years old AT LEAST, judging by the state of those toy kits when I got into it, I'd say they'd been doing it for a while at that point too.
Persistent Volume manager for Kubernetes - https://github.com/dwimsey/openshift-pvmanager
http://www.imdb.com/title/tt0083530/quotes
Oh, cut the bleeding heart crap, will ya? We've all got our switches, lights, and knobs to deal with, Striker. I mean, down here there are literally hundreds and thousands of blinking, beeping, and flashing lights, blinking and beeping and flashing - they're *flashing* and they're *beeping*. I can't stand it anymore! They're *blinking* and *beeping* and *flashing*! Why doesn't somebody pull the plug!
Went to find a video clip of this and well it's been taken down so the quotes will have to do.
Don't know something? Look it up. Still don't know? Then ask.
And without significant success: IrDA. The culprits were the inverse square law, multipath and capacitance. It's hard to detect a flickering LED in the mass of light we typically use to avoid running ourselves into doorframes. A light source focussed and concentrated on a detector works well, a detector scanning a large angle, not so well. Walls reflect light and pulses equally well, and the further you are from the light source, the harder it will be to pick out the right signal in all the noise. Lastly, to get a high data rate, you need high speed LEDs and high current drivers. These are more expensive than DC driven light emitters.
wherein a method of communication is described by using modulated light in a multiplicity of codings is used to send information between a multiplicity of sites.
http://tech.slashdot.org/story/10/12/27/1911223/using-led-ceiling-lights-for-digital-communication
Of course news about a fake are Fake News.
An LED that flickers with a high-frequency signal and looks like it's always on?
You mean like pretty much every optical SPDIF interface on the planet?
"Nine times out of ten, starting a fire is not the best way to solve the problem." - my wife