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Researchers Beam 230Mb/sec Wireless Internet WIth LEDs

timothy posted more than 4 years ago | from the binded-by-the-light dept.

Networking 218

MikeChino writes "A group of scientists from Germany's Fraunhofer Institute have devised a way to encode a visible-frequency wireless signal in light emitted by plain old desklamps and other light fixtures. The team was able to achieve a record-setting data download rate of 230 megabits per second, and they expect to be able to double that speed in the near future. While the regular radio-frequency Wi-Fi most of us use currently is perfectly fine, it does have its flaws — it has a limited bandwidth that confines it to a certain spectrum and if you've ever had someone leech off of your connection, you know that it also leaks through walls. LED wireless signals would theoretically have none of these downsides."

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No upsides either (4, Informative)

IICV (652597) | more than 4 years ago | (#31445728)

"Leaking through walls" isn't a bug, it's a feature; I don't want to wire my whole house for Ethernet just to have wireless in every room, as that defeats the purpose.

Re:No upsides either (0)

Anonymous Coward | more than 4 years ago | (#31445808)

It doesn't have upsides for your home, yes. It's hard to say why the summary tries to play that up as an advantage for home users. There are, however, plenty of situations where wireless may be desirable within a confined area, LOS exists to all end points and you want to make sure that no one outside of that area can attach to the network.

Re:No upsides either (0)

Anonymous Coward | more than 4 years ago | (#31446104)

If you're all in the same room, this is just a very expensive plug. If you're not, it won't work. I'm not sure how else it could work.

Re:No upsides either (1)

WrongSizeGlass (838941) | more than 4 years ago | (#31446490)

This won't help any outdoor wireless networks so indoors is all they've got.

Re:No upsides either or side-by-sides (0)

Anonymous Coward | more than 4 years ago | (#31445880)

No way ... is that too early for April Fools ???

I can Haz Beam-of-Light Interwebs ???

No kitty, that's my pot pie! (3, Funny)

Anonymous Coward | more than 4 years ago | (#31445944)

No, you can not haz beam of light interwebs. You are obviously a lolcat, and the only thing lolcats should do with beams of light is chase them. Who is a cute kitty? Who is? You! Yes you are!

Re:No upsides either (5, Insightful)

maxume (22995) | more than 4 years ago | (#31445892)

That's a huge upside for linking up video devices though. No interference from the neighbors, no interference from the other room.

Re:No upsides either (1)

Midnight Thunder (17205) | more than 4 years ago | (#31447188)

That's a huge upside for linking up video devices though. No interference from the neighbors, no interference from the other room.

There is probably another use (ironically based off 'NCIS: LA') which I can think of: temporary connection to a visual display device without needing a physical connection. Imagine the following:

You have a large display screen in the conference room with a line of sight receptor built in. You want to quickly show something to everyone in the room, but don't want to spend time leaning over to physically connect to the device or set up any special network connections (think security issues). Instead you simply point your iPad type device towards the screen and hey presto you are sharing what you see on your device with everyone else in the room. Since it is line of sight you know no one outside the room can tap it.

Beyond that you could do the same with game consoles. You charge up the device, remove it from its charging cradle and simply point it to the TV. No cables and easy way of deciding which device is making use of the TV.

Re:No upsides either (1)

Mr0bvious (968303) | more than 4 years ago | (#31446138)

Huh? lack of wiring is not the only benefit of wireless.. How about being untethered to your network? That sounds like a pretty large benefit to me..

Re:No upsides either (1)

martas (1439879) | more than 4 years ago | (#31446176)

what if you could use the lighting that already exists in your house to do this? kinda like internet over power lines?

Re:No upsides either (5, Funny)

Anonymous Coward | more than 4 years ago | (#31446228)

I tried that in my epilepsy classroom and everyone had a fit.

Re:No upsides either (1)

icebike (68054) | more than 4 years ago | (#31446372)

what if you could use the lighting that already exists in your house to do this? kinda like internet over power lines?

Probably not. The summary mentions "plain old desk lamps", but TFA is specific in stating the lamps must be LED, which is still not common.

Incandescent can't be modulated at the frequencies necessary for anything much beyond S O S signals.

Of course once all your house lighting is converted to LED, your network might work provided you modulated at least one lamp in every room. This of course would leak out windows, which the Summary writer would be perfectly fine with, even tho he disparages leaking radio waves.

Re:No upsides either (0)

Anonymous Coward | more than 4 years ago | (#31447084)

Indeed, incandescent lamps were used as a crude RMS integrator in one of the first automatic gain circuits...

Re:No upsides either (4, Interesting)

Nefarious Wheel (628136) | more than 4 years ago | (#31446928)

what if you could use the lighting that already exists in your house to do this? kinda like internet over power lines?

Retailers already use this technology to change the display tags on shelves. After hours, they send a series of codes to modulate the fluorescent lighting in such a way that it sends new data to smart shelf tags. The shelf tags display a product name and a price. Changing the prices on those shelf tags are a major operational cost of grocery retailers.

Fujitsu is one of the firms offering this. Here's Fujitsu's system [fujitsu.com] .

Re:No upsides either (2, Interesting)

DigitAl56K (805623) | more than 4 years ago | (#31446408)

Leaking through walls is not always a feature. I can't get the maximum benefit of my Wifi setup because I live in an apartment building and all my neighbors have devices chattering on every channel. All their routers are probably defaulted to high power, and there's nothing I can realistically do to improve my situation except switch to 802.11n/5G, which I did, and now I'm seeing more routers on that frequency range too.

I don't want to lose my through-walls access, but if it could be heavily supplemented by light within my own home then I have an extra channel that my neighbors systems won't degrade. Even better if the lights can work as repeaters so if I leave some doors open I can get good signal around many corners, and better still if they also support several invisible frequencies so that my signal strength doesn't depend on bright lighting (or any lighting!) and devices like IR remotes don't interfere when you use them. I've also heard others complain their microwave kills their wifi, and I don't know if that's true or not, but if it is then there is another practical problem solved by this technology.

Tell people about the practical benefits. As far as any security related story, I don't care. I already use WPA2/AES. 99.99% of the population probably doesn't care beyond that, either.

If you want the signal to go through walls... (1)

NotQuiteReal (608241) | more than 4 years ago | (#31446442)

The Fraunhofer Institute also has an audio-frequency wireless solution that will go through walls, with the proper amplification.

Very high bandwidth, it conveys a lot of information, especially in thin-walled multiple dwelling buildings.

Re:If you want the signal to go through walls... (1)

noidentity (188756) | more than 4 years ago | (#31446658)

The Fraunhofer Institute also has an audio-frequency wireless solution that will go through walls, with the proper amplification.

Very high bandwidth, it conveys a lot of information, especially in thin-walled multiple dwelling buildings.

Unfortunately the teenagers who drive down the street at night also have this technology, though there's about zero information content to the "boom boom boom" sound it makes. It certainly penetrates walls, thick or thin, and is definitely audible.

Re:No upsides either (0)

Anonymous Coward | more than 4 years ago | (#31446938)

Why wire your house, just put mirrors everywhere.

Re:No upsides either (1)

Nefarious Wheel (628136) | more than 4 years ago | (#31447012)

Why wire your house, just put mirrors everywhere.

Sorry, no. I have two daughters. It's hard enough to get them moving as it is.

Re:No upsides either (2, Interesting)

sexconker (1179573) | more than 4 years ago | (#31447040)

Why wire your house, just put mirrors everywhere.

Just make sure to use an even number of mirrors.
Using an odd number of mirrors will flip your bits and should only be used when pairing two computers together.

Eventually most ports will automatically handle both setups, but Dell will inexplicably ship systems that don't for decades to come.

Re:No upsides either (1)

blackC0pter (1013737) | more than 4 years ago | (#31447090)

While LED based internet is a nice idea, the technology is still immature. You should look at Laser based systems (Free Space Optical). They are deployed and running now. I am just about to sign up for such a service in Los Angeles. They offer up to 100Mb/s at rates about 1/4 to 1/5 the cost of hard fiber. I did a lot of research and the latency is extremely low on these laser based systems (near zero since it works at layer 1) but the downside is the attenuation in space due to rain, snow and fog. Basically, rain and fog increase the bit error rate and decrease the effective distance between two end points. However, the charts showed that this technology was viable at 500+ meters. In Los Angeles, the downtime will be negligible due to the weather. Also, the provider I am looking at doesn't have very large gaps between lasers so the weather will affect the system even less. Also, it's nice having a very fast connection to my datacenter in one wilshire from the office. Note, some of the FSO systems go up to 10Gbps.

Here is the ISP for the FSO system: http://www.aerioconnect.net/ [aerioconnect.net]

Here is the equipment manufacturer for FSO systems: http://www.lightpointe.com/products/default.cfm [lightpointe.com]

Just different ones (4, Insightful)

MozeeToby (1163751) | more than 4 years ago | (#31445762)

LED wireless signals would theoretically have none of these downsides.

Nope, instead it'll have a whole range of different ones, such as requiring line of site.

Re:Just different ones (2, Funny)

wealthychef (584778) | more than 4 years ago | (#31445788)

I don't think "site" means what you think it means.

Re:Just different ones (2, Insightful)

Uranium-238 (1586465) | more than 4 years ago | (#31445934)

You know what he meant really and he's quite right too. People could dick with these connections by putting a piece of paper infront of the transmitter or receiver. This just sounds like a uesless idea.

Re:Just different ones (1)

twidarkling (1537077) | more than 4 years ago | (#31446132)

Forget people being a dick, how about people just innocently wandering between transmitter and reciever? Or the user himself accidentally setting something down in the way? Too many ways to screw it up.

I think we had a story about LOS wireless before, and really, same as then, the only use I can see for it is in lab environments, where you usually don't have people wandering around in undefined patterns. Attach unit to roof on a per-row basis, aim all computers in that row at that reciever, and no one can accidentally interrupt the beam. Beyond that, I can't see a common residential use, or much industrial use.

Re:Just different ones (1)

tlhIngan (30335) | more than 4 years ago | (#31446252)

Forget people being a dick, how about people just innocently wandering between transmitter and reciever? Or the user himself accidentally setting something down in the way? Too many ways to screw it up.

I think we had a story about LOS wireless before, and really, same as then, the only use I can see for it is in lab environments, where you usually don't have people wandering around in undefined patterns. Attach unit to roof on a per-row basis, aim all computers in that row at that reciever, and no one can accidentally interrupt the beam. Beyond that, I can't see a common residential use, or much industrial use.

Who says using a light based PHY means it has to be direct line of sight? There's one common technology that uses light, yet for the most part, indirect line of sight works quite well. It's called Consumer IR, and it powers your remote controls. With many modern remotes, you don't have to aim the remote at the device, but you can bounce it off walls and furniture and have it work great.

Don't forget, 802.11b works on two different bands. One is 2.4GHz, another is IR.

Re:Just different ones (2, Informative)

twidarkling (1537077) | more than 4 years ago | (#31446320)

With many modern remotes, you don't have to aim the remote at the device, but you can bounce it off walls and furniture and have it work great.

Tell that to my fucking Blu-Ray player. The remote for my parents' 15 year old TV worked better at wider angles.

Besides, the article mentioned Visible Spectrum. Good luck reflecting that and maintaining usefulness.

Re:Just different ones (0)

Anonymous Coward | more than 4 years ago | (#31446412)

Good luck reflecting that and maintaining usefulness.

I live in a hall of mirrors you insensitive clod.

Re:Just different ones (1)

Gilmoure (18428) | more than 4 years ago | (#31446428)

Cats! That'll do in this stuff.

Re:Just different ones (2, Funny)

mrclisdue (1321513) | more than 4 years ago | (#31446202)

If we continue to make a spelling mistake in each reply, at some point approaching infinity, we may have reconstructed the bible: to discover that you read it first on /..

chers,

Re:Just different ones (5, Funny)

Maxo-Texas (864189) | more than 4 years ago | (#31446270)

Slashdot 57:30, If we covet making a spelling mistake for each wife, at some point we forsake other gods and we may do unto others before they can do unto us first on /..

Re:Just different ones (1)

WrongSizeGlass (838941) | more than 4 years ago | (#31446310)

That's why we should just skip LED's and go straight to lasers. Or lightning. Need to download really big file? Try our 'lightning fast wireless service'.

Re:Just different ones (1, Offtopic)

noidentity (188756) | more than 4 years ago | (#31446672)

That's why we should just skip LED's and go straight to lasers.

NOW I know why the sharks have their lasers... it's for communications!

Re:Just different ones (1)

The Mighty Buzzard (878441) | more than 4 years ago | (#31447096)

Yeah but since this is /. you have to go the extra step and think of some of the creative uses you could put those to. For instance, say your neighbor's kid keeps waking you up by playing outside your window every morning.

"Gah, fucking kid!"
*reorients laser networking device that's been slightly modified*
$sudo ifup zap0
*chuckles maniacally*

Re:Just different ones (1)

Surt (22457) | more than 4 years ago | (#31446686)

If you allow such people in your house, you really get what you deserve.

Re:Just different ones (1)

Maxo-Texas (864189) | more than 4 years ago | (#31446250)

Nah, he's just playing fast and lose with spelling.

Re:Just different ones (1)

Chris Burke (6130) | more than 4 years ago | (#31446242)

Yeah I like how being able to go through walls is listed as a downside. Though I guess if leeches are your biggest concern, it is an improvement. They'd still exist, but you'd be a lot more likely to notice the guy sitting outside your window with a laptop than if he was in his own home.

I remember in college making a radio and a wireless speaker system on the same breadboard, using an LED to transmit the audio from the radio to the amplifier. It was a pretty cool thing to do in a lab, but it didn't occur to me to rush home and duplicate this amazing feat on my home stereo.

Re:Just different ones (1)

camperdave (969942) | more than 4 years ago | (#31446446)

In businesses security is a big issue, and being able to stop a wireless signal at the office wall would be a huge plus.

Re:Just different ones (2, Insightful)

Chris Burke (6130) | more than 4 years ago | (#31446560)

And losing your network connection because you were sitting at the wrong end of the conference table in your meeting would be a huge minus.

And having the signal stop at the wall but not at the window sounds like a major ding to the "huge plus", not to mention a recipe for a false sense of security.

In either case you'd have to secure your wireless network in a traditional fashion. So, why not just do that, and get the benefit of non-line-of-sight communication too?

Re:Just different ones (0)

Anonymous Coward | more than 4 years ago | (#31446514)

Line-of-sight should not be a huge issue.

"The signal would be generated in a room by slightly flickering all the lights in unison." [sciencedaily.com]

Looks like something based off ambient lighting. A couple of light sources should be sufficient to get around LOS issues.

Re:Just different ones (1)

Cassius Corodes (1084513) | more than 4 years ago | (#31446722)

Yes... that would not be annoying at all.

Oh Great (1)

WrongSizeGlass (838941) | more than 4 years ago | (#31445766)

A Desklamp? Other light fixtures? What's next, the overheard fluorescent lights??

Now everything I own, from my Star Wars light saber to my Krusty the Klown glow-in-the-dark alarm clock, could potentially with wireless signal. Oy carumba

Re:Oh Great (1)

weirdo557 (959623) | more than 4 years ago | (#31445872)

did you accidentally with your wireless signal

Re:Oh Great (1)

WrongSizeGlass (838941) | more than 4 years ago | (#31446002)

Indeed I did. It appears I had an extra helping of dumbass for lunch, and I should never have that much at one sitting.

Re:Oh Great (2, Informative)

noidentity (188756) | more than 4 years ago | (#31446730)

Now everything I own, from my Star Wars light saber to my Krusty the Klown glow-in-the-dark alarm clock, could potentially with wireless signal. Oy carumba

That's actually been a documented problem in some devices with status LEDs, which inadvertently leaked information [cnet.com] due to being tied directly to the (serial) data line, rather than a low-pass filtered version of it.

Re:Oh Great (1)

zippthorne (748122) | more than 4 years ago | (#31447160)

Apparently the National Security Agency, the federal agency responsible for military intelligence and the security of the U.S. government's communications, believes the threat to be low-risk.

Said a spokesman on his way into the building carrying a large box labeled "Etalons, 550nm, Tunable."

Re:Oh Great (1)

jgreco (1542031) | more than 4 years ago | (#31447250)

I keep having this vision of Cmdr. Data on that episode of TNG where he suddenly appears on the bridge with a rapidly flashing palm light. Maybe this will not only do our networking, maybe it'll be able to fix brainwashing too. (And if it can fix it, betcha someone can hack it to DO the brainwashing too...)

Blast from the past (5, Funny)

jpmorgan (517966) | more than 4 years ago | (#31445774)

It's the return of IrDA!

Re:Blast from the past (1)

salesbot (1524011) | more than 4 years ago | (#31446334)

It's the return of IrDA!

only this version is Jonny Mnemonic compatible!

Re:Blast from the past (1)

idontgno (624372) | more than 4 years ago | (#31446502)

And junkie dolphins can have forehead communications lasers as well as SQuIDs!

Perfect!

Fraunhofer juggernaut (2, Informative)

Anonymous Coward | more than 4 years ago | (#31445798)

http://en.wikipedia.org/wiki/Fraunhofer_Society [wikipedia.org]

(anon, copied from wiki, I just thought people should be more aware that Fraunhofer is an amazingly huge beast.

It employs over 12,500, mainly scientists and engineers, with an annual research budget of about €1.2 billion

The Fraunhofer Society currently operates 59 institutes. These are Fraunhofer Institutes for:

        * Algorithms and Scientific Computing - SCAI
        * Applied Information Technology - FIT
        * Applied Optics and Precision Engineering - IOF
        * Applied Polymer Research - IAP
        * Applied Solid State Physics - IAF
        * Biomedical Engineering - IBMT
        * Building Physics - IBP
        * Center for Molecular Biotechnology- CMB
        * Ceramic Technologies and Systems - IKTS
        * Chemical Technology - ICT
        * Communication Systems - ESK
        * Computer Architecture and Software Technology - FIRST
        * Computer Graphics Research - IGD
        * Digital Media Technology - IDMT
        * Electron and Plasma Technology - FEP
        * e-Government - Fraunhofer eGovernment Center
        * Environmental, Safety and Energy Technology - UMSICHT
        * Experimental Software Engineering - IESE
        * Factory Operation and Automation - IFF
        * High-Speed Dynamics, Ernst-Mach-Institut - EMI
        * Industrial Engineering - IAO
        * Industrial Mathematics - ITWM
        * Information and Dataprocessing - IITB
        * Information Center for Regional Planning and Building Construction - IRB
        * Integrated Circuits - IIS
        * Integrated Systems and Device Technology - IISB
        * Integrated Publication and Information Systems - IPSI
        * Intelligent Analysis and Information Systems - IAIS
        * Interfacial Engineering and Biotechnology - IGB
        * Laser Technology - ILT
        * Machine Tools and Forming Technology - IWU
        * Manufacturing Engineering and Applied Materials Research - IFAM
        * Manufacturing Engineering and Automation - IPA
        * Material and Beam Technology - IWS
        * Material Flow and Logistics - IML
        * Mechanics of Materials - IWM
        * Medical Image Computing - MEVIS
        * Microelectronic Circuits and Systems - IMS
        * Molecular Biology and Applied Ecology - IME
        * Telecommunications, Heinrich-Hertz-Institut - HHI
        * Non-Destructive Testing - IZFP
        * Open Communication Systems - FOKUS
        * Patent Center for German Research - PST
        * Photonic Microsystems - IPMS
        * Physical Measurement Techniques - IPM
        * Process Engineering and Packaging - IVV
        * Production Systems and Design Technology - IPK
        * Production Technology - IPT
        * Reliability and Microintegration - IZM
        * Secure Information Technology - SIT
        * Silicate Research - ISC
        * Silicon Technology - ISIT
        * Software and Systems Technology - ISST
        * Solar Energy Systems - ISE
        * Structural Durability and System Reliability - LBF
        * Systems and Innovation Research - ISI
        * Technological Trend Analysis - INT
        * Technology Development Group - TEG
        * Surface Engineering and Thin Films - IST
        * Toxicology and Experimental Medicine - ITEM
        * Transport and Infrastructure Systems - IVI
        * Wind Energy and Energy System Technology - IWES
        * Wood Research, Wilhelm-Klauditz-Institut - WKI

FhG owns MP3 (2, Informative)

tepples (727027) | more than 4 years ago | (#31445910)

Fraunhofer Society (FhG) is the organization that owns the MP3 patents and licenses them through RCA.

download is fine but how about uploads? (0)

Anonymous Coward | more than 4 years ago | (#31445806)

appears quite unidirectional to me

Don't look into the light!?! (1)

tootalltom (1097273) | more than 4 years ago | (#31445810)

Anyone bother to ask the epileptics how they feel about this?

Re:Don't look into the light!?! (1)

Jeremi (14640) | more than 4 years ago | (#31445854)

According to TFM, the flickering is slight enough to be imperceptible by humans. So unless epileptics have superhuman sensitivity to tiny light variations, I doubt they will notice anything either.

Re:Don't look into the light!?! (0)

Anonymous Coward | more than 4 years ago | (#31446282)

Not only that, but flickering a light at a speed that could transmit 230Mb, it's going to be so fast you're not going to be able to see it...even if it were from 0% to 100% intensity... Our eyes can't see flickering much past 75Hz or so...this is going to be in the MHz.

Re:Don't look into the light!?! (1)

magarity (164372) | more than 4 years ago | (#31445874)

Don't worry, the flicker rate is so fast not even Bobby Fischer would complain about it.

Re:Don't look into the light!?! (1)

santax (1541065) | more than 4 years ago | (#31445938)

Hehehe, just as long as you made sure he didn't knew before hand it was flickering... *sorry, that man is both my hero (first part of life) as my anti-hero (his later days)*

Re:Don't look into the light!?! (1)

MichaelSmith (789609) | more than 4 years ago | (#31446954)

I have a seizure disorder, but according to my EEG I am not photosensitive. Generally you would worry about pulses below 100hz. This system sends data at megabits per second so there is no primary need to pulse at low frequencies. I a imagine that starting and stopping downloads (say) could generate visible pulses but I am sure the system could be designed not to behave that way.

I have read that usable data can be extracted from the TX/RX LEDS on some hubs and switches. I am more concerned about the 9-12Hz pulsing LED lights on bicycles. I don't use them on my bike.

Great! (1)

TrippTDF (513419) | more than 4 years ago | (#31445832)

So now I'll have a strobe light effect every time I check my email!

Re:Great! (1)

smd75 (1551583) | more than 4 years ago | (#31445886)

Do you have a strobe effect with your lights on normally? Im assuming this will be at a frequency higher than humans can perceive. Which doesnt require much above 60hz because thats what most lights operate at normally

You won't notice it (1)

tepples (727027) | more than 4 years ago | (#31445978)

So now I'll have a strobe light effect every time I check my email!

As long as the modulation they use on the LEDs is DC-free, your eyes won't pick up this strobing. A traditional light bulb flickers at 100 or 120 Hz, and you probably don't notice it. So you definitely won't notice flicker that's a million times faster.

Re:You won't notice it (1)

harrkev (623093) | more than 4 years ago | (#31446090)

Since they got 230MB per second, you can safely assume that the modulation will be in the gigahertz. Good luck seeing that. If they use something like 8B/10B encoding, then they will get a guaranteed 50% duty cycle, so there will never be any brightness variation visible to the human eye.

Re:You won't notice it (0)

Anonymous Coward | more than 4 years ago | (#31446288)

But I bet my cat will.

Re:Great! (1, Funny)

Anonymous Coward | more than 4 years ago | (#31445984)

It goes well with the porn! This is red light, right?

One small problem (0)

Anonymous Coward | more than 4 years ago | (#31445894)

Any epileptic within a one mile radius is turned into a flesh-eating zombie.

Transparent walls (1)

lcampagn (842601) | more than 4 years ago | (#31445930)

LEDs don't transmit through walls unless they happen to be transparent, like, say, a WINDOW. And while your GHz-based wireless signal drops off just down the block, the signals leaking through your window can be picked up from miles away with a telescope. Didn't we learn this from the modem-blinkenlights exploit like 10 years ago? I suppose most of us have also learned how to use encryption in the interim..

Re:Transparent walls (1)

zippthorne (748122) | more than 4 years ago | (#31447218)

No, you can pick up any signal that leaks with an appropriate sized telescope. It's just that due to the wavelength, the telescope required to resolve an LED from four miles away will fit in a van, while the telescope required to resolve your wireless emissions would be pretty conspicuous.

An idea that's been around (2, Interesting)

dtmos (447842) | more than 4 years ago | (#31445990)

US patent 6,542,270 [uspto.gov] ("Interference-robust coded-modulation scheme for optical communications and method for modulating illumination for optical communications"), issued April 1, 2003, assigns direct sequence spread spectrum-type codes to each overhead fluorescent light, so that communication and location-determination can be performed. The chip frequency of the coding scheme is fast enough that there is no human-audible or -visual effect, and supportable by electronic ballasts.

Utterly Stupid.... (3, Insightful)

loose electron (699583) | more than 4 years ago | (#31445992)

If you really want to use optical communocation you might as well go infrared so you don't need to see it, similar to your TV remote.

Then you have all the problems (visible light or infrared) of orientation, line of sight and similar.

Hopefully the creator of this gadget has not quit their day job.

utterly stupid.

Re:Utterly Stupid.... (1)

femto (459605) | more than 4 years ago | (#31446740)

Not as dumb as you think. By using visible light, the system gets to use infrastructure that will be in place anyway. (Think this will be combined with data over powerlines? You betcha.) That saves energy and costs. In addition, the transmitter power is much higher than would be used for IR, so one gets greater SNR and higher speed data. The lighting system of a building also lights up every nook and cranny, overcoming most line of sight issues. Finally, the visible spectrum is pretty well unregulated, so bandwidth is free.

I think it's a killer application, and that it will soon be providing lots of people with day jobs.

Re:Utterly Stupid.... (1)

dominious (1077089) | more than 4 years ago | (#31446748)

just because you don't see any potential applications it doesn't mean it's "utterly stupid". Line of sight is not so difficult if all I want is to stream from my laptop to the tv to watch a HD movie with some friends.

Ok this is /. No friends, forgot.

Re:Utterly Stupid.... (0)

Anonymous Coward | more than 4 years ago | (#31446826)

I can imagine a very useful situation for this: Spying
If you can turn something as innocuous as a light into your comms you have a secret network connection that no normal person would ever suspect existed. Extreme Big Brother environments have lights everywhere. Do you think even the most hardcore of spooks would think to check the frequency of the lights?

Re:Utterly Stupid.... (1)

Nefarious Wheel (628136) | more than 4 years ago | (#31447164)

I can imagine a very useful situation for this: Spying

Meh. Easier than that. Bounce a laser signal against any window (larger the better) where you want to hear the occupants. As the window responds to the change in internal pressure caused by the vibrations of speech, your return signal will reflect that change with a difference in the angle of the return beam. You do need to watch your beam alignment though, so that the return laser beam impacts your photoreceptor array. It's simple laser interferometry from that point. Stick the signal difference through an oscillator/amp and listen to all the boring crap being spoken on the other side of the window. FFT for noise cancellation.

Early push button office telephones had the clear plastic buttons illuminated by a light that was in circuit with the audio. You used to be able to read those directly with a telescope with a photodiode at the focus. Very easy thing to do.

Re:Utterly Stupid.... (1)

project-nova (930308) | more than 4 years ago | (#31446962)

Visible-frequency wireless works by flickering all the lights in a room ever so slightly -- so slightly, in fact, that the human eye could never detect it.

The idea is to re-use your existing LED room lights to also transmit a data signal, *not* some completely new tech!

Re:Utterly Stupid.... (0)

Anonymous Coward | more than 4 years ago | (#31446994)

When you are pumping 10 Watts into a device, there is the 'green' argument for using that energy for more than just data transmission.

What I want to know is: (4, Funny)

killmenow (184444) | more than 4 years ago | (#31446006)

What happens if you cross the beams?

I RTFA (2, Interesting)

harrkev (623093) | more than 4 years ago | (#31446026)

I RTFA. It says that they achieve the bandwidth by filtering out the blue light. This makes sense, as white LEDs are actually blue LEDs with phosphors added to get the other colors. Phosphors are similar to glow-in-the-dark stuff, so they retain light for a little while. Presumably, the blue filter is only needed over the receiver.

The one questions is: how does your laptop equipped with this technology talk back? Will your laptop have a multi-watt emitter on the top (read "bright white light") lighting up the room for the upstream traffic?

Re:I RTFA (1)

Chris Burke (6130) | more than 4 years ago | (#31446134)

The one questions is: how does your laptop equipped with this technology talk back? Will your laptop have a multi-watt emitter on the top (read "bright white light") lighting up the room for the upstream traffic?

Naw, it's like some satellite internet connections. You use the LED for download, and upstream you use dialup. I'm sure it'll catch on. :)

Re:I RTFA (1)

c0lo (1497653) | more than 4 years ago | (#31446520)

I RTFA. It says that they achieve the bandwidth by filtering out the blue light

Proud, huh? Then, I suggest you doing it again:

Luckily, researchers were able to expand the bandwidth by leaps and bounds by filtering out all but the blue light (cool!).

Which makes sense, given that blue has a higher freq in the spectrum.
Otherwise it would be like: now, filter out the green and increase the bandwidth a.s.o.

Re:I RTFA (1)

c0lo (1497653) | more than 4 years ago | (#31446756)

On the same line, cannot stop wondering what's next?
I mean: to remove the limitations of walls being opaque to Vis light and increase the bandwidth, one can imagine using hard X-Rays and gamma radiation as a carrier for WiFi, ain't it?

Go figure: applying the Niquist-Shanon theorem [wikipedia.org] , the bandwidth would be around 15 PHz: yes, right, peta-hertz, about 12 orders of magnitude higher than the puny 230 MHz - at this rate, one would download a BlueRay full-quality-rip movie in a matter of nanoseconds - that's for sure faster than any epileptic cat would be able to notice and throw a fit.

I just can't wait! No, seriously, I really can't hold my breath that long (i.e. until this quantum-leap technology becomes commercially available).

Oh, and ... (3, Informative)

dtmos (447842) | more than 4 years ago | (#31446116)

Those interested in this LED-based technology can check out the IEEE 802.15.7 Visible Light Communication Task Group [ieee802.org] . Members of the Fraunhofer Institute are regular contributors to the standard.

Re:Oh, and ... (2, Informative)

xigxag (167441) | more than 4 years ago | (#31446566)

Members of the Fraunhofer Institute are regular contributors to the standard.

In that case, it's bound to be cool. And by cool, I mean patent encumbered.

BTW, {nitpick} it's not "the" Fraunhofer Institute, it's "Fraunhofer Society [fraunhofer.de] ," within which are various institutes [fraunhofer.de] . Probably the most famous is on the internet is the Fraunhofer Institute for Integrated Circuits (Fraunhofer IIS) in Erlangen, whence came the mp3 standard. But the one responsible for Visible Light Communication is Fraunhofer HHI [fraunhofer.de] in Berlin. {/nitpick}

Re:Oh, and ... (1)

dtmos (447842) | more than 4 years ago | (#31446856)

In that case, it's bound to be cool. And by cool, I mean patent encumbered.

Not if they want the standard to be approved. 802.15 voters do not take kindly to approving standards for which they will then have to pay royalties to use. Politically, it's almost impossible to get a royalty-bearing patented technology into an 802.15 standard.

I accidentally (1)

ijakings (982830) | more than 4 years ago | (#31446196)

I accidentally the entire visible spectrum.

This is great... but... (3, Funny)

troylanes (883822) | more than 4 years ago | (#31446256)

I'm an epileptic you insensitive clod!

Re:This is great... but... (1)

MichaelSmith (789609) | more than 4 years ago | (#31446842)

(pre woosh)

Photo sensitivity in seizure disorders is generally for pulses below 20Hz and definitely below 100Hz. It is legitimate to ask why bicycle head and tail lights are allowed to pulse at 9-12Hz.

It's the clacks! (0)

Anonymous Coward | more than 4 years ago | (#31446298)

Vetinari abides.

I will screw with your download (1)

ParanoiaBOTS (903635) | more than 4 years ago | (#31446312)

I will get an LED flashlights and screw your downloads all to hell

big whoop (4, Funny)

pablo_max (626328) | more than 4 years ago | (#31446330)

We do the same thing at work with Interns and flashlights.

No problem (1, Informative)

Anonymous Coward | more than 4 years ago | (#31446578)

The modulation frequency is much too high to be perceptible. If an encoding is used which has a constant light/dark ratio, the light will look perfectly steady. (LEDs are often driven with an unfiltered pulse width modulation signal in the kHz range and that doesn't cause problems with epileptics. This technique uses hundreds of MHz.)

Seizure LAN (0)

Anonymous Coward | more than 4 years ago | (#31446610)

I just had a seizure thinking about it.

Wait for the first idiots to... (0, Flamebait)

Hurricane78 (562437) | more than 4 years ago | (#31446612)

...protect themselves from desk lamp radiation.

After all, it’s 3000 times more powerful! So it must be like... OMGDEADLYWTFBBQ!!!1!1one(lim (x->0) (sin(x)/x))

I remember a DIY LED netsystem.... (4, Informative)

Ogi_UnixNut (916982) | more than 4 years ago | (#31446622)

...called Ronja, only 10-mbits/sec, but ~1.4km range, and it could all be built by yourself. Quite cool IMO. You can find out more info (on the now bit dated) site here: http://ronja.twibright.com/ [twibright.com]

Re:I remember a DIY LED netsystem.... (1)

EkriirkE (1075937) | more than 4 years ago | (#31447146)

I've been looking for this site again forever, thanks! It's applied to many-a-slashdot story claiming to have invented something similar

related idea (1)

sonamchauhan (587356) | more than 4 years ago | (#31446690)

A light pen that 'reads' an 'imperceptible flickering' LCD screen to both figure out which point its touching, and the data the PC wants to send at that point

Sounds familiar. (0)

Anonymous Coward | more than 4 years ago | (#31446780)

Wow, I've never seen a device [wikipedia.org] which used light and line of sight to communicate before!

Where is this useful? (1)

MikShapi (681808) | more than 4 years ago | (#31446860)

This would be
[a] a dedicated technology you need to explicitly buy gear for, rather than use what you implicitly get in nearly every device you buy - phone, lappie, printer, home SAN, what have you.
[b] they wont sell as many radios as the wifi people do, so dont expect anywhere near the same price for a device with a radio on it.
[c] Wifi would advance faster (in bandwidth and price primarily). As would Wireless USB, Bluetooth 4.0, etc.
[d] you'd need to go back to the days of pointint irda devices. Consumer inconvenience.

This would have an advantage where you want to set up line-of-sight comms, wireless doesnt cut it (cuz you're in an appartment building in the middle of Hong Kong or something), and cabled ethernet is not good enough. AND the consumer is sufficiently inconvenienced by wifi to go through this hassle.

Which accounts for about 0.00000000000001% of the consumer base. (The vast majority of which, as stated, couldn't be f#@!%ed and will opt to use Wifi anyway)

Who's funding this? PALM?

zenith space commander (1)

mirix (1649853) | more than 4 years ago | (#31447042)

zenith made the first remote controls, they used ultrasonic chimes for signaling. A side affect was the TV would change channels when people dropped pots and pans.

IR sucks. visible sucks even more, because there happens to be a lot of interference. I suppose they could compensate for static levels of ambient light, but you still need line of sight, which is a pain... and you need light, which is a pain if you're watching a movie in the dark on a laptop or so...

RF is really the only way for mobile stuff. Fixed links between fixed installations could be light/laser though. Have fun aligning the laser though, and enjoy the light pollution for less focused light sources. Not to mention that rain, snow, and fog tend to render optical systems useless.

IrDA died for a good reason. (3, Insightful)

teh dave (1618221) | more than 4 years ago | (#31447112)

In case they hadn't noticed, IrDA is dead for a good reason. The fact that the last two versions of it are much faster than Bluetooth (2.x) is irrelevant, it's too much of an inconvenience for most of its potential users in comparison to Bluetooth. It was great before Bluetooth came about and I used the latest versions of it with my old phone because it was much faster than Bluetooth, and I never had a problem with it for that purpose. Most potential users prefer the convenience of Bluetooth though, for obvious reasons. My new phone doesn't have IrDA, and hardly any new phones do, and as far as consumers go, that technology is all but dead. I can see LED networking going the same way.
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