The Notebook Review forums were hosted by TechTarget, who shut down them down on January 31, 2022. This static read-only archive was pulled by NBR forum users between January 20 and January 31, 2022, in an effort to make sure that the valuable technical information that had been posted on the forums is preserved. For current discussions, many NBR forum users moved over to NotebookTalk.net after the shutdown.
Problems? See this thread at archive.org.

    LiFi optical wireless data transmission

    Discussion in 'Networking and Wireless' started by alexhawker, Aug 31, 2017.

  1. alexhawker

    alexhawker Spent Gladiator

    Reputations:
    500
    Messages:
    2,540
    Likes Received:
    792
    Trophy Points:
    131
    http://www.newequipment.com/researc...20170831_NED-09_96&sfvc4enews=42&cl=article_1

    "What is LiFi?

    LiFi is a high-speed, secure, fully networked wireless communication technology similar to Wi-Fi. However, LiFi utilizes the entire light spectrum where Wi-Fi utilizes radio frequencies (RF).

    To do this, the LED light fixtures used in many energy-conscious homes and offices are outfitted with a module that controls the light for optical data transmission. The high speed light pulses are invisible to the naked eye, yet can be used to transmit data at extremely high speeds to a receiving device located in a laptop, computer tower, cell phone or other smart device."

    Get ready for all the PWM-sensitive folks to complain about headaches in the workplace...
     
    hmscott likes this.
  2. Vasudev

    Vasudev Notebook Nobel Laureate

    Reputations:
    12,045
    Messages:
    11,278
    Likes Received:
    8,815
    Trophy Points:
    931
    I'm one of them. I remember my friend doing a seminar on LiFi like it was yesterday.
     
    hmscott, Starlight5 and downloads like this.
  3. mujtaba

    mujtaba ZzzZzz Super Moderator

    Reputations:
    4,242
    Messages:
    3,088
    Likes Received:
    507
    Trophy Points:
    181
    Let's pretend nothing happened here :p
     
    Vasudev, alexhawker and hmscott like this.
  4. Starlight5

    Starlight5 Yes, I'm a cat. What else is there to say, really?

    Reputations:
    826
    Messages:
    3,230
    Likes Received:
    1,643
    Trophy Points:
    231
    As far as I read, LiFi tops out at 1Ggps in real life. How is it any better than current-gen WiGiG that already performs faster without annoying PWM-sensitive people?
     
    Vasudev and hmscott like this.
  5. bennni

    bennni Notebook Evangelist

    Reputations:
    91
    Messages:
    450
    Likes Received:
    278
    Trophy Points:
    76
    The article mentions that you could use existing LED light fixtures to transmit the signal in each room. This would in theory equate more consistent reception, as each room effectively has a signal receptor. No more inconsistent WiFi signal, which requires multiple routers/boosters to get perfect coverage everywhere.

    The downside, is that every room needs one of the LiFi receptors, making it somewhat inflexible if I'm reading this correctly.

    Had to laugh at the size of the "pureLifi-X" LiFi dongle in relation to the table that it's plugged into - but no-doubt, it can and will be made smaller.
     
    hmscott likes this.
  6. hmscott

    hmscott Notebook Nobel Laureate

    Reputations:
    7,110
    Messages:
    20,384
    Likes Received:
    25,139
    Trophy Points:
    931
    There shouldn't be any possible way with Lifi frequencies and data transmission rates so high that they would would be detectable - even in people most sensitive to light variations like PWM.

    Infrared light was used for networking back in the 90's by Apple, and although it wasn't successful long term due to the slowness of the data rate of the equipment available at the time, it was very useful before Wifi as a quick set up alternative to wires.

    IRTalk, IrDA, and the Mac
    http://lowendmac.com/2015/irtalk-irda-and-the-mac/

    There were offices set up with these emitters and receivers with lots of people working in them that were completely unaware IR light networking transceivers were in use.

    Given the health concerns of RF from Cell phones, Wifi and BT, this visible light network might be a good alternative for offices and public places.

    I have the lights off or dim them frequently, and I always like to turn the lights off if I leave a room or portion of the house, and so do many other people. Visible light solutions might not fit well into homes, but businesses might be fine with it.

    I think there is still a market for networking with light outside the visible spectrum like the previous IR solutions, but that would require additional fixtures in addition to office lighting fixtures.

    Integrating the functionality in every day lighting is the selling point for Lifi, but I think it simply "hides" the costs of the networking infrastructure components as there are costs over and above the costs of simple lighting.

    Those additional costs over and above basic lighting fixture costs if unbundled from the basic lighting costs would provide funding for the implementation of independent invisible light spectrum networking components that would keep working when I hit the light switch :)
     
    Last edited: Sep 2, 2017
    Vasudev and Starlight5 like this.
  7. alexhawker

    alexhawker Spent Gladiator

    Reputations:
    500
    Messages:
    2,540
    Likes Received:
    792
    Trophy Points:
    131
    From the FAQ on the company's site:

    "If all power to a light is turned off then there is no LiFi. However, LiFi technology can be enabled to dim low enough that a room will appear dark and still transmit data. There is consistent performance between 10 and 90 percent illumination.

    Currently, pureLiFi’s technology provide communications at light levels down to 60 lux. For comparison the British standard for minimum light level for reading is 400 lux.
    There are also other options for using invisible parts of the light spectrum such as infra-red, which is currently already being used for sending information back to the lightbulb (uplink)."


    Sent from my iPhone using Tapatalk
     
    Vasudev, Starlight5 and hmscott like this.
  8. hmscott

    hmscott Notebook Nobel Laureate

    Reputations:
    7,110
    Messages:
    20,384
    Likes Received:
    25,139
    Trophy Points:
    931
    That's good to know, if there were a way to expand the IR use that would be great. I wonder what the light bulb efficiency is at 60 lux or minimum for communications, that's the real concern leaving the lights on 24/7 to keep the clients online.
     
    alexhawker and Vasudev like this.
  9. Mr.Koala

    Mr.Koala Notebook Virtuoso

    Reputations:
    568
    Messages:
    2,307
    Likes Received:
    566
    Trophy Points:
    131
    Well, if this thing gets popular you could always install a secondary data-light.
     
    alexhawker, hmscott and Vasudev like this.