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Using LED Ceiling Lights For Digital Communication
PatPending writes "A Minnesota start-up company, LVX, is developing products under several patents and about a dozen pending applications, e.g., 'Building illumination apparatus with integrated communications, security and energy management,' that put clusters of LEDs in a standard-sized ceiling light fixture. The LEDs are in optical communication with special modems attached to office computers. The first generation of the LVX system will transmit data at speeds of about three megabits per second, roughly as fast as a residential DSL line. LVX Chief Executive Officer John Pederson said a second-generation system that will roll out in about a year will permit speeds on par with commercial Wi-Fi networks. It will also permit lights that can be programmed to change intensity and color. Pederson said the next generation of the system should get even more efficient as fixtures become 'smart' so the lights would dim when bright sunlight is coming through a window or when a conference room or hallway is empty. Hurdles: speed and installation costs. No word on the reliability and security of this system."
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What one fool can do, another can. (Ancient Simian Proverb)
I don't see how this is much better than the IRDA infrared that used to be built into laptops, printers, mice, etc. It got replaced by radio technology several generations ago.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
Kohls has had technology like this in their stores for a little while now. They use the lights to update little LED price tags throughout the store. I think Fujitsu makes the tech, though I could be wrong. Anyone wanna help me out on this?
The "integrated security" of the "illumination apparatus" means you can kill the communication link by quickly putting the computer with the "special modem" under your desk, and out of line-of-sight with the ceiling LEDs.
If it operates in the infrared spectrum, the bonus is that most glass blocks it, so it would be harder to get a signal. The downside is, a sufficiently sensitive thermal camera with LoS to the bulb or a reflector in LoS with the bulb would give it to you.
#fuckbeta #iamslashdot #dicemustdie
From TFA:
Mohsen Kavehrad, a Penn State electrical engineering professor who has been working with optical network technology for about 10 years, said the approach could be a vital complement to the existing wireless system. He said the radio spectrum usually used for short-range transmissions, such as Wi-Fi, is getting increasingly crowded, which can lead to slower connections. "Light can be the way out of this mess," said Kavehrad, who is not involved in the LVX project.
What one fool can do, another can. (Ancient Simian Proverb)
They're also working on a getting a patent for a new modem where you just set the phone headset right on the modem, by sticking both round parts in little earmuff thingies. Apparently it's only good for a couple hundred bits per second now, but they claim the next version will reach speeds in excess of 1000 bits per second. No word on whether it will work with cell phones.
slashdot = stagnated.
This from the /. Troll with dozens of /. accounts. From
http://slashdot.org/~MichaelKristopeit300
now through
http://slashdot.org/~MichaelKristopeit328
More intelligent use of the spectrum is the solution, not light.
Technically speaking, isn't light part of the spectrum?
From what I've read about this, while the LED lights are optical, the transmission line, aka the power line will still be used to carry data transmissions to and from the LED lights, I don't see how this or any other BPL tech being allowed by the FCC then again anything these days is allowed to pass through and transmit whatever it wants all over the Shortwave radio bands under FCC Part 15 rules, Plasma TV's being just one example which plasters the lower shortwave radio band with an insane amount of interference. Please lets stop using power lines for data transmissions, all it does is cause headaches and takes a dump all over the shortwave band! We've already got WiFi, we don't need yet another standard that is just going to end up plastering interference all over the entire street, and probably causing rife with our bodies as well. Just imagine what the implications would be of this, every person in your street or unit could then have a hardwired connection to your ethernet network as long as they knew the correct password, usually default, no need to use high powered wireless adapters anymore.... I can see how a means of optical data transfer would be a good idea over infrared, It would be more healthier for our brains than wireless, IRDA springs to mind, but as soon as you put the blanket over your laptop the signal drops out completely. Its a worthless technology which will just end up spluttering interference over the entire lower shortwave band, making the valuable and irreplacable shortwave band useless for long distance DX contacts, what happens when we need that band in times of emergency? Oh wait, we can't use it because somebody needs their broadband fix, doh!
*sigh* More intelligent use of the radio frequency spectrum.
Damn pedantics =)
Damn pedantics =)
I believe you mean "damn pedants". Pedantic is an adjective.
Just sayin...
/...
Having this in offices/factories would eliminate 'network' from the list of worries when you restack cubes, or re-arrange focus factories.
Display some adaptability.
+1, Pedantic.
I'm not a coward by any name.
The first generation of the LVX system will transmit data at speeds of about three megabits per second, roughly as fast as a residential DSL line.
Is that physical layer rate? If so, what's the rate after protocol overhead?
Let's assume that is the physical layer rate. Which would make it three and a half times slower than 802.11b, and 18 times slower than 802.11g, which is virtually everywhere. And, drumroll please, at least one hundred times slower than 802.11n, which is 300-600Mbit/sec (physical layer speed.)
Please help metamoderate.
Hide a sensor anywhere nearby, and you can read all the internal traffic.
Drop a tiny node in a plushy on someones desk, spewing out all sorts of Window virus, and see how long it takes for the IP staff to find it.
Shine a modulated laser beam through a window, and disrupt all the network traffic in an office.
Who would win this election: Andrew Weiner vs Andrew Weiner's weiner.
Ouch. That's rough. You would almost be better off with something like shitty HughesNet with their 250Mb per day bandwidth cap. Of course latency would be an issue. Also, who's the asshat that modded C64 offtopic? I suppose the bit about comcast doesn't add anything useful to the discussion, but it is at least partially related to the article at hand. If anything my comment is offtopic.
The teachers will crack any minute, purple monkey dishwasher.
Saving you from running cable that last 6 feet?
It saves the company from running cable that last average of 100 feet or so from the wiring closet to each desk, multiplied by the number of desks on the floor (in this building there are about 100 desks per floor) multiplied by the number of times cube moves take place (you don't want to know how often this is, but triennial is not far from the truth) multiplied by the cost for an electrician to run a single line of cable. I think the average cost to pull a single run ranges from about $200-$400 on up, depending on the city and state, and that's in a newer building designed to have cable runs to desks. If you consider a older building with no pre-existing trenches in the floor, the costs treble.
And LED light fixtures are more efficient than fluorescent tubes. Electricity costs spent on lighting will be cut in half or more. LEDs have a much longer lifetime than fluorescent tubes, and will cut maintenance visits to replace bulbs by a factor of 10.
The numbers multiply out rapidly. Fixed wiring and fluorescent lighting might cost a company several hundred dollars per employee annually to run and maintain. A Fortune 500 company might have 10,000 employees or more, so that could be tens of millions of dollars a year in savings.
Of course, there are the offsetting expenses. This licensed and patented blinkenlight technology isn't free. It needs expensive LED lamps to be installed at each light fixture. It will need ethernet runs to each fixture to carry the data, if the power lines can't do it, or if it doesn't use RF. It'll require special light receiver dongles for each PC and laptop. And this new technology won't be bug free. It will have maintenance costs of its own, not to mention a few rounds of upgrades as people realize they screwed up the security protocols when they first invented it (WEP is neither gone nor forgotten.)
So far, 802.11 is much cheaper as the components are off-the-shelf, but the band is crowded and congestion isn't improving over time. This looks like one way to mitigate it, but until they address the low bandwidth I doubt it will take off.
John
Light therapy for Seasonal Affective Disorder ("SAD") can be implemented with LEDs. While it's typically used in 30min bursts first thing in the morning, I wonder if it can be spread out through a longer time and worked into standard lighting via this kind of array. Very intersting...
Use my userscript to add story images to Slashdot. There's no going back.
3Mbit/sec is plenty for voice and texting. With every room/hallway fed separately (via fibre) you can run every single cellphone in the building without using RF. If you wanted to eliminate exposure to RF/EM fields that would certainly help. Also you can modulate different colours independently to multiply bandwidth. Your so called white room lights could easily consist of a dozen LED's tuned to a specific frequency. Also given that cheap fibre systems can use LED's as transmitters and your total bandwidth could easily reach 1000 MBit/sec range.
IBM has/had key patents in this area for decades, and offered wireless office networking from ceiling-mounted LED lamps about 30 years ago. Some of those patents were apparently used in the first wireless PC keyboard--for the PCjr (aka "Peanut")--the second version of which was actually a very nice wireless keyboard. I'm assuming IBM's patents in this area are what kept other optical wireless keyboards and networking gear off the market. -bernieS
Modify all the lights produced by a factory to carry network traffic, but don't advertise it. Modify all cellphones (in software) to listen for that network, and send back a ping when it gets a connection. Make a list of all the replies and wait for a target of interest. You've now got an unmonitored link to that targets cellphone/pda/laptop. This would be very useful for spying on Iran/China/Interpol etc. If the system rarely sends traffic then the odds of accidentally finding it is very low. And yes, even though China makes everything they just build to plan so they wouldn't know about the "extra" bits.
I just can't see why this has to be wired.
I mean, don't LED lights get their energy from the aether?
-- Tigger warning: This post may contain tiggers! --
Parent was making a joke, probably, but back when 10Mbit network hubs were the latest thing the LEDs would flicker directly with activity and it actually was possible to spy on the network given determination and the proper equipment.
That's all well and good until the visible spectrum gets overloaded with competing and incompatible communications protocols. The way out of this mess is for upcoming 802.11 wireless protocols to get their own piece of spectrum.
Even if windows gave you some filtering, you'd still have to deal with insiders, virus-infected users, etc. If you want security, you still need to use crypto.
Bill Stewart
New Fast-Compression-only CPR http://preview.tinyurl.com/dy575ks
You know, I heard rumors about that, but I don't see how it could have possibly worked. The light flickered as traffic went by. Knowing that a packet was sent is useless if you don't know the payload of it.
This is a different case entirely though. Well, mostly. They've reinvented fiber optic networks, without the fiber. Of course, that increases the noise for the receiving end, the chances for interception, and the ability for someone to break a connection with a Post-It note or paintball gun.
Serious? Seriousness is well above my pay grade.
I prefer mine much higher on the spectrum. Closer to 10^20Hz. It takes care of pesky problems in your transmission stream too.
Serious? Seriousness is well above my pay grade.
-1, Pedantic. ?
[The Universe] has gone offline.
This will be nothing more than a toy communications protocol or a very niche market for manufacturing or retail outfits that can use a low bandwidth, unreliable, wireless, non-radio communications protocol. It could be really helpful in places with lots of RF interference that precludes the use of the wireless 802.11 protocols. But even if they do address the bandwidth, I can't see how this could be much more reliable than the existing IR or laser based networking products.
Bandwith-wise, this has the same problems as wireless. Wireless communications (aside from lasers or directional microwaves) are by necessity a shared transmission medium. With 802.11b/g (2.4 GHz) you can only colocate 3 access points without them starting to interfere with each other. 802.11a (5 GHz) is better. It allows 4 access points before they impede on each other, but it's also more expensive. That may be fine for some cubical farms, but for most, sharing 33 Mb (802.11b), 162 Mb (802.11g), or 216 Mb (802.11a) of bandwidth is unworkable. Only 802.11n is potentially usable in this sort of situation with a maximum of 600 Mb per access point. These numbers are all theoretical, of course, so real world conditions will reduce throughput significantly. With a white-light based technology you wouldn't probably even have the option of co-locating 3 or 4 transponders. Wired Ethernet does not have this problem, which is why we use it for dense computing environments, like computer labs and cubical farms.
I also think you also misrepresent the costs of a wired installation. At 200 to 400 per drop, your number are probably pretty accurate for a new installation. 10,000 empoyees x $400 = 4 million bucks. But even if these drops only last 3 years, it averages to only around 1.3 million per year in rewiring. However, when reconfiguring a network it is not necessarily required to pull new wire. Wires can be relocated as long as the new location is not farther from the wiring closet. If the original installers were smart, they would also have left some extra wire spooled up just in case of a move. If all that is needed is moving a drop 5 feet to the right, the wire can probably accommodate it, and that will cost far less than pulling new wire. A 12 foot patch cable and some wire management can also mean drops don't have to be relocated. Our hypothetical Fortune 500 will spend far short of tens of millions per year on rewiring. And since you mentioned the trienniel cubical reconfiguration, don't ignore the trienniel desktop refresh. 802.11cards don't come standard in desktops. Dell charges about 50 bucks to add an 802.11b/g wireless card. That's an extra half a million dollars every three years when you refresh desktops for your 10,000 cubical dwellers
OK, so I know my back-of-the-envelope calculations are not exactly accurate either, and I've left out more detail than I included. But every time I hear someone say how much cheaper it is to go wireless, I just have to point out the flaws in the scheme.
Thanks. My back-of-the-envelope is a lot less optimistic than yours, as I was trotting out worst cases on all counts.
What I really wanted to do was answer the GP as to "why" a company might want to avoid the last-mile expenses of a cubicle farm. I don't think for a moment that it's a good idea, mind you, because I agree that hard-wired installations are always technically superior to wireless in terms of performance.
For grins, follow the LVX link to their "technology introduction" page, where you'll find some great FUD:
On the other hand, it has long been established that light is an extraordinary carrier of digital information. The fastest networks today are equipped with fiber optic cabling and equipment. The next generation of wireless networks will use light as its communication medium because of these superior attributes.
The way they weasel-worded it is as if the technical benefits of fiber optics are magically conferred upon all optical communications media, especially including their scheme.
But my original point was that there is a complex cost equation that goes hand-in-glove with the technical arguments, and that it's not just as simple as "saving you from running cable that last 6 feet". And yes, Fortune 500 companies are stupid enough to put in bad or inferior technical solutions just because they "reduce costs". Trust me on this one. :-)
TFA's point is that if the company is already going to replace fluorescent or incandescent ceiling lamps with LEDs for energy reasons, this company is saying they should consider offsetting the higher cost of the LEDs by adding the extra hardware to outfit them as networking transceivers.
John
If your lights are being used as a cableless fiber optic system, what is to keep big brother from sitting outside and picking up the communications from the street?
It's used to send pricing information to LCD price displays attached to shelves via the supermarket lighting (it's done at night when there's no-one around to be affected by it, and in any case since it's at a much higher frequency than the usual 50Hz flicker it wouldn't be noticed anyway). Think of the usual paper price tags in plastic holders attached to shelves, but now they have LCD displays and are updated automatically by modulating the in-store lighting.
HHI is already doing that, saw it in FOE2010.
-- I was raised on the command line, bitch