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Researchers Beam 230Mb/sec Wireless Internet WIth LEDs

Posted by timothy on from the binded-by-the-light dept.

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."

13 of 218 comments (clear)

  1. No upsides either by IICV · · Score: 4, Informative

    "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.

    1. Re:No upsides either by maxume · · Score: 5, Insightful

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

      --
      Nerd rage is the funniest rage.
    2. Re:No upsides either by Anonymous Coward · · Score: 5, Funny

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

    3. Re:No upsides either by Nefarious+Wheel · · Score: 4, Interesting

      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.

      --
      Do not mock my vision of impractical footwear
    4. Re:No upsides either by GrpA · · Score: 4, Interesting

      Even if it doesn't have windows open, you can still go through a closed or even shuttered window. Telescopes replace direction antennas and have phenomenal gain and accuracy. Lasers beamed back in can return signals and don't have to be visible ( You can control transmit spectrum a lot easier than receive spectrum ). AlGaAs based photonic detectors can pick up single photons and are sensitive enough to spot light coming through a thin gap in shutters or curtains. ( think more sensitive than military NV devices ).

      Now, instead of being worried about people parking in cars just up the street, you need to worry about anything you can see from your house... Thos e hills 10km away? Not far enough. The highrise across the river? Huge risk.

      The good news is that tinfoil is sufficient to stop all photons, so a few rolls of tinfoil and tinfoil plated tape will be all you need to secure the wireless visible spectrum devices in your house.

      Until someone burns a ten micron hole in your defenses with an infra-red laser....

      GrpA

      --
      Enjoy science fiction? "Turing Evolved" - AI, Mecha, Androids and rail-gun battles. What more could you want?
    5. Re:No upsides either by noisyinstrument · · Score: 5, Funny

      People who live in glass houses shouldn't use plain text passwords.

  2. Just different ones by MozeeToby · · Score: 4, Insightful

    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.

    1. Re:Just different ones by Maxo-Texas · · Score: 5, Funny

      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 /..

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  3. Blast from the past by jpmorgan · · Score: 5, Funny

    It's the return of IrDA!

  4. What I want to know is: by killmenow · · Score: 4, Funny

    What happens if you cross the beams?

  5. big whoop by pablo_max · · Score: 4, Funny

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

  6. I remember a DIY LED netsystem.... by Ogi_UnixNut · · Score: 4, Informative

    ...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/

  7. Digital video by BillX · · Score: 4, Funny

    I assume the 230Mb/s is for stuff like delivering digital video to your TV without plugging cables.

    "Wow, this movie looks even better in digital!"

    "Here, let me turn the lights out so we can wa...oh."

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