Wireless data can be delivered by LED lights, anywhere: call it ‘Li-Fi’

[one...two...tree 2,762]

Think about it: around the world, there are millions of street lamps, in every city and town on every continent. One visionary has a proposal to put each and every one of these lamps to work for a new purpose beyond illuminating the street below. They could serve as wireless Internet access points, communicating to devices, as well as vehicles.

Harald Haas, a professor of engineering at Edinburgh University, even has a name for this new networking technology: “Li-Fi,” for light-fidelity.

At a recent TED conference, Haas pitched his proposal for Li-Fi data transmission, suggesting that the applications and capacity for data would be limitless — from using car headlights to transmit data, or employing line of sight light sources as data transmitters.

Haas says data can be transmitted via LED bulbs that glow and darken faster than the human eye can see.

The system, which he’s calling D-Light, uses a mathematical trick called OFDM (orthogonal frequency division multiplexing), which allows it to vary the intensity of the LED’s output at a very fast rate, invisible to the human eye. For the eye, the bulb would simply be on and providing light. The signal can be picked up by simple receivers. As of now, Haas is reporting data rates of up to 10 MBit/s per second (faster than a typical broadband connection), and 100 MBit/s by the end of this year and possibly up to 1 GB in the future.

There’s plenty of capacity, he says: “We have 10,000 times more spectrum, 10,000 times more LEDs installed already in the infrastructure. You would agree with me, hopefully, there’s no issue of capacity anymore.” The added bonus, he adds, is that the infrastructure is free, and even would promote more rapid adoption of more energy-efficient LED bulbs. “It should be so cheap that it’s everywhere,” Haas says. “Using the visible light spectrum, which comes for free, you can piggy-back existing wireless services on the back of lighting equipment.”

Plus, there would be wireless access points anywhere there is a light source. Even smartphones, with their LED displays, could serve as data sources. Consider all the possibilities, Haas elaborates:

“…In hospitals, for new medical instruments; in streets for traffic control. Cars have LED-based headlights, LED-based back lights, and cars can communicate with each other and prevent accidents in the way that they exchange information. Traffic lights can communicate to the car and so on. And then you have these millions of street lamps deployed around the world. And every street lamp would be a free access point.”

Security is another benefit, he points out, since light doesn’t penetrate through walls, he points out.

http://www.smartplanet.com/blog/business-brains/wireless-data-can-be-delivered-by-led-lights-anywhere-call-it-8216li-fi/18180

[rsn 135]

Sounds like a neat idea, but, as with most things, the devil is in the details.

100 Mbps will be useful for home networks, but not terribly useful for internet access. I'm not aware of any ISPs that offer more than 50 Mbps service, and that is quite expensive and rare.

Note: Whoever wrote this article needs to get their acronyms straight (megabits = Mb, megabytes = MB, gigabit = Gb, gigabyte = GB)

Edited August 24, 2011 by rsn

[Zero Sum 305]

Sounds like a neat idea, but, as with most things, the devil is in the details.

100 Mbps will be useful for home networks, but not terribly useful for internet access. I'm not aware of any ISPs that offer more than 50 Mbps service, and that is quite expensive and rare.

Note: Whoever wrote this article needs to get their acronyms straight (megabits = Mb, megabytes = MB, gigabit = Gb, gigabyte = GB)

Now you know how I feel every GW thread where we're expected to take 1) some dude's internet opinions as a smoking gun of proof and 2) someone's biased opinion about what constitutes a scientific finding.

[rsn 135]

Now you know how I feel every GW thread where we're expected to take 1) some dude's internet opinions as a smoking gun of proof and 2) someone's biased opinion about what constitutes a scientific finding.

I think you are comparing apples and oranges. This was simply a fun, entertaining article. Not exactly political in nature. I think we can agree that GW has become a political topic.

[Zero Sum 305]

I think you are comparing apples and oranges. This was simply a fun, entertaining article. Not exactly political in nature. I think we can agree that GW has become a political topic.

Yes, we can agree it certainly is a political topic, particularly when the actual science is ignored. And therein are the demonic details which you brought up in your own post.

[rsn 135]

Yes, we can agree it certainly is a political topic, particularly when the actual science is ignored. And therein are the demonic details which you brought up in your own post.

I wasn't questioning the science of the original article. I was simply pointing out a couple issues with the practical application of the idea.

[Zero Sum 305]

I wasn't questioning the science of the original article. I was simply pointing out a couple issues with the practical application of the idea.

I know you weren't. As I point out the flaws in claiming skepticism in a science certain 'skeptics' show no proof of actually understanding. You point out obvious pragmatic issues that are right on target. Others... not so much, while these things are obviously brought to their attention to their stubborn denialism. Clearly you should see the parallels.

[rsn 135]

You are talking about an issue specific to global warming as far as I can tell. Perhaps that should be discussed in a global warming thread and not one about wireless internet.

[Zero Sum 305]

You are talking about an issue specific to global warming as far as I can tell. Perhaps that should be discussed in a global warming thread and not one about wireless internet.

You understand I am talking about a parallel, right?

Let me re-post just part of the first post I had here, in case you think I want to make this about GW science.

"Now you know how I feel every GW thread "

[rsn 135]

You understand I am talking about a parallel, right?

Let me re-post just part of the first post I had here, in case you think I want to make this about GW science.

"Now you know how I feel every GW thread "

Perhaps you'd like to bring up a parallel involving the mating habits of moles while you're at it?

Edited August 25, 2011 by rsn

[Zero Sum 305]

Perhaps you'd like to bring up a parallel involving the mating habits of moles while your at it?

Or of Steve Irwin and how he will return from the grave.

[rsn 135]

Or of Steve Irwin and how he will return from the grave.

Precisely!

[Zero Sum 305]

As long as we focus on Steve and not a retarded critique of his wardrobe... then we'd be following the logic I'd prefer, not what we see with nutters focusing on non-science while calling it scientific proof.

[Dan and Judy 614]

I can't trust any technology called li fi

[Usui Takumi 1,562]

Perhaps you'd like to bring up a parallel involving the mating habits of moles while you're at it?

like mating a few moles of carbon and oxygen?

Edited August 25, 2011 by Sousuke