Scientists create wireless network with LED room light

Scientists create wireless network with LED room light

Summary: German researchers have demonstrated how regular LEDs can be turned into an optical WLAN with only a "few additional components."

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Lights are no longer just for lighting up.

Scientists from the Fraunhofer Institute for Telecommunications, Heinrich Hertz Institute (HHI) in Berlin, Germany, have developed a new kind of optical WAN with enough throughput to allow four people in a room to watch a film from the Internet on their laptops, in HD quality.

The technology can potentially be used on both laptops and mobile telephones.

Credit: Fraunhofer HHI

Credit: Fraunhofer HHI

The researchers say they've achieved a transfer data rate of 100 megabits per second (Mbit/s) without any losses, using LEDs in the ceiling that light up more than ten square meters (90 square feet). This area also marks the radius in which the receiver -- a simple photo diode on the laptop -- can be placed before it is out of range.

In lab tests, the team pushed speeds even further using red-blue-green-white light LEDs. Those transmitted data at a blistering 800 Mbit/s, setting a record for VLC or visible light communication.

Klaus-Dieter Langer, the project leader said:  “For VLC the sources of light – in this case, white-light LEDs – provide lighting for the room at the same time they transfer information. With the aid of a special component, the modulator, we turn the LEDs off and on in very rapid succession and transfer the information as ones and zeros."

The system works because the modulation of the light is imperceptible to the human eye. Langer explains: "The diode catches the light, electronics decode the information and translate it into electrical impulses, meaning the language of the computer.“

While rigging a system to turn LEDs into a transfer medium may not require many components, sending data over light waves is not without challenges. The key one is that whenever on object (like a hand) comes between the light and the photo diode the transfer is impaired.

The HHI scientists stress that the optical WAN is not intended to replace other networks, but rather serve as an additional and low-invasive option in environments where radio transmission networks are not desired or not possible, such as hospital surgical rooms.

"Combinations are also possible, such as optical WLAN in one direction and PowerLAN for the return channel. Films can be transferred to the PC like this and also played there, or they can be sent on to another computer," notes a release.

The scientists will demonstrate how videos are transmitted by light at the International Telecommunications Fair IFA (Internationale Funkausstellung IFA) in Berlin from September 2-7, 2011.

Related:

MIT: built-in motion sensors in devices improve wireless data rates

A wireless radio that can send and receive signals at the same time

'Microring' wireless devices could nix wires in homes, offices

Topics: Mobility, Laptops, Networking, Wi-Fi

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15 comments
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  • RE: Scientists create wireless network with LED room light

    Give me a break. These were engineers, not scientists!
    mmarquis
    • RE: Scientists create wireless network with LED room light

      @mmarquis Not to mention the fact that leaning over your laptop (or shelves above your desktop) creates shade, which breaks the network. I can't see anyone using this in real-world applications, so they shouldn't pat themselves on the back too hard.
      BillDem
  • RE: Scientists create wireless network with LED room light

    Engineers, scientists - they're all boffins.
    christopher_jablonski
    • RE: Scientists create wireless network with LED room light

      @christopher_jablonski - now, now. I'd like to see you get through the day without anything developed by an engineer or scientist. It's easy to bad mouth us, but you couldn't live your life without us!
      omb00900@...
  • RE: Scientists create wireless network with LED room light

    I seem to recall infra-red LED comms ports being pretty standard a few years back. Is this not just retro technology?
    colincooper@...
  • RE: Scientists create wireless network with LED room light

    That's 900 square feet ( not 90). Do the math.
    tb@...
    • RE: Scientists create wireless network with LED room light

      @tb@... Wrong! An area of ten square meters is not a 10 by 10 meter area (which would actually be 100 square meters)! It's still off by a little bit, though. The exact conversion for 10 square meters is 107.64 square feet. YOU do the math! Now don't you feel silly?
      omb00900@...
  • RE: Scientists create wireless network with LED room light

    This is great, until someone turns off the lights!
    boomchuck1
    • RE: Scientists create wireless network with LED room light

      @boomchuck1
      LMAO :D
      MrElectrifyer
  • RE: Scientists create wireless network with LED room light

    I wonder what the impact is on the LED bulb though.

    Currently LED bulbs are still pretty expensive, but people want them because they use little power and last a long time.

    Cycling them off and on for for high speed data transmission has to have a significant impact on the lifespan at least, but I wouldn't be surprised if it affected power consumption as well.
    krclark
    • RE: Scientists create wireless network with LED room light

      @krclark They are likely galium arsenide, like most LEDs or similar ..CR standard diodes that happen to emit light, p-n junctions are p-n junctions, everything obviously has fail point, but your question is quite valid as i'm sure they dont know really either. Sure you can extrapolate and such but remember when they said all HDD would die within a finite time period..well that never really happened either did it..
      pelicansnout
  • RE: Scientists create wireless network with LED room light

    Take this tech and feed it over a TOSLink cable, and you may have something.
    Champ_Kind
    • RE: Scientists create wireless network with LED room light

      @Champ_Kind Wired fiber optic connections already exist- this is wireless :)
      Gritztastic
  • RE: Scientists create wireless network with LED room light

    This is majorly cool. I would like to have this sort of capability in my house. Certain devices, like media centers, printers, etc that don't move and are in places not likely to have blocked light, could benefit from this sort of thing.

    Hopefully they work out the details and commercialize it within a few years.
    chadpengar
  • RE: Scientists create wireless network with LED room light

    Nice, starting to wonder how much my electricity bill is gonna get boost from this :)
    MrElectrifyer