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Li-Fi-like System Pushes 100Gbps Within a Small Room

Posted by Soulskill on from the go-big-or-go-home dept.

An anonymous reader writes: Oxford University is [building] a system that takes light from the fiber, amplifies it, and beams it across a room to deliver data at more than 100 gigabits per second. ... The trick, of course, is getting the light beam exactly where it needs to go. An optical fiber makes for a target that's only 8 or 9 micrometers in diameter, after all. The team, which also included researchers from University College, London, accomplished this using so-called holographic beam steering at both the transmitter and receiver ends. These use an array of liquid crystals to create a programmable diffraction grating that reflects the light in the desired direction. ... With a 60-degree field of view, the team was able to transmit six different wavelengths, each at 37.4 Gb/s, for an aggregate bandwidth of 224 Gb/s (abstract). With a 36-degree field of view, they managed only three channels, for 112 Gb/s.

38 comments

  1. Don't gloss over the dynamic holograms so quickly by Anonymous Coward · · Score: 0

    What's that about? Does it involve some hitherto unseen display resolutions? How long does it take to calculate the pattern?

  2. ..."lif-fi"!? by Anonymous Coward · · Score: 0

    Just... no.

    Clever, but... please, no.

    1. Re:..."lif-fi"!? by rossdee · · Score: 1

      Agreed, Li means Lithium

    2. Re:..."lif-fi"!? by redwraith94 · · Score: 1

      Seconded.

      Light-Fidelity ... means nothing
      Wireless-Fidelity ... meant nothing
      Hi-Fidelity as in a sound system actually meant something once.

      --
      I art more snarky, and terse than thou. I art Slashdot!
    3. Re:..."lif-fi"!? by ColaMan · · Score: 1

      'Fidelity' in the wireless sense was because the methods and algorithms developed by the CSIRO had a considerable impact on the recovery of the transmitted signal.

      --

      You are in a twisty maze of processor lines, all alike.
      There is a lot of hype here.
    4. Re:..."lif-fi"!? by redwraith94 · · Score: 1

      It seems to me that fidelity is a requirement for anything digital to operate, and it isn't really used anywhere else in computer parlance. I always assumed it was borrowed by 'marketing speclalists' from hi-fi for stereo systems, since that was always taken to be the 'high-end' version of a stereo, and it makes more sense to me as a claim of high-fidelity in an analog system, where the end result can approximate the original, and still get away with it.

      Or put more simply lo-fi computer system = bsod.

      --
      I art more snarky, and terse than thou. I art Slashdot!
  3. Resonace: Beings of Frequency by Anonymous Coward · · Score: 0

    Resonace: Beings of Frequency

    1. Re:Resonace: Beings of Frequency by davester666 · · Score: 1

      "The trick, of course, is getting the light beam exactly where it needs to go"

      I know, lets call this trick "a laser".

      --
      Sleep your way to a whiter smile...date a dentist!
    2. Re:Resonace: Beings of Frequency by HiThere · · Score: 1

      Lasers need to be quite accurately directed. You may well need a laser to generate the signal, but you probably want to focus it at a mirror that will spread the signal around the room. The trick is to either avoid or allow for multi-path "ghosts". This will even allow the receiver to be moving around within the room (as long as it is moving "slowly" enough .. and my rough guess is that anything slower than 100 Kps would count as slow enough).

      --

      I think we've pushed this "anyone can grow up to be president" thing too far.
  4. Do Not Look Into Laser With Remaining Eye? by cruff · · Score: 3, Funny

    Aaaah! My eye!

  5. While the idea it good. Impractical by jellomizer · · Score: 1

    Wi-fi key advantage is the fact that it goes threw walls and a single router can give strong coverage in you home, as well most small offices.
    This is a point of sight technology. So for home or office it will need to be Non obstructive.
    You are still better off with wired if you need such speed, the wire will just be more convenant and dependable

    --
    If something is so important that you feel the need to post it on the internet... It probably isn't that important.
    1. Re:While the idea it good. Impractical by FlyingGuy · · Score: 4, Informative

      goes threw walls

      Tell that to anyone with a house that is more than 400 sqft and they will laugh in your face. 2.4ghz is radar! It is supposed to be reflected. 2.4ghz is smack in the middle of the "E" band radar spectrum and that is why Wifi has a range of about 100 ft indoors and that is if your house is made after 1950. If you have lathe and plaster, forget about it!

      --
      Hey KID! Yeah you, get the fuck off my lawn!
    2. Re:While the idea it good. Impractical by Anonymous Coward · · Score: 0

      Maybe you didn't notice the 100Gbps part? This is so much faster than any wire-based consumer networking tech, that no one would care that it fails to go through walls.

    3. Re: While the idea it good. Impractical by Anonymous Coward · · Score: 0

      Our house is 4000sqft, worked with a single router fairly well though we added a second one recently. Airport express and AirPort Extreme, range is good and haven't noticed any dead spots

    4. Re:While the idea it good. Impractical by Anonymous Coward · · Score: 0

      For you, proof reading is just something that happens to other people eh?

    5. Re:While the idea it good. Impractical by Anonymous Coward · · Score: 0

      Maybe you didn't notice the 100Gbps part? This is so much faster than any wire-based consumer networking tech, that no one would care that it fails to go through walls.

      What, are you retarded? Fiber can already get into the Tbps.

      What do you call a wireless technology that only works LOS in a single room? A solution in search of a problem.

      Anyone who needs speed and reliability will be using a wire, and anyone needing more flexibility will be using a radio transceiver that doesn't need to be placed in a very specific site in order to work.

    6. Re: While the idea it good. Impractical by Anonymous Coward · · Score: 0

      You mean proofreading (one word), right?

    7. Re:While the idea it good. Impractical by sribe · · Score: 1

      ...Tell that to anyone with a house that is more than 400 sqft.... Wifi has a range of about 100 ft indoors

      Which means the range covers over 30,000 sqft. Now of course your house is not perfectly round, and your access point won't be in the exact center. But there's still plenty of margin to cover a decent-sized house.

    8. Re:While the idea it good. Impractical by Anonymous Coward · · Score: 0

      I said consumer networkng. Tbps-class fiber is not consumer networking.

    9. Re: While the idea it good. Impractical by Anonymous Coward · · Score: 0

      Neither is this lab bench experiment, yet. Intel's reflective optical cable makes it as easy to work with as ethernet, which is near its practical limit for humans being able to terminate it to spec. 60 degrees is too narrow to put in a wall plate. Good start but line of sight is too limiting. Once they can do reflections, we'll be getting somewhere. Obviously this is necessary progress towards that.

    10. Re:While the idea it good. Impractical by Anonymous Coward · · Score: 0

      I said consumer networkng. Tbps-class fiber is not consumer networking.

      ...despite the fact that this is nowhere near available as a product, for either the enterprise *or* the domestic consumer. Tbps class fiber is far more of a consumer product than this "product" that exists only in a university research lab.

      Also, I'm guessing your idea of a *consumer* networking environment allows rigid emplacement of direct LOS optical transceivers but somehow precludes far simpler, more reliable fiber interconnects.

      Do you have a short position on fiber networking companies or something? You're certainly shoveling a lot of shit.

    11. Re:While the idea it good. Impractical by Anonymous Coward · · Score: 0

      But that is *outdoors*. Inside, most of the installs I've done for Comcast have trouble reaching all of a two bedroom apartment. I had to use three access points for my 900 sq ft two bedroom apartment. I can pick-up more than 120 other wireless networks so combating that much interference is hard. My old place was a 400 sq ft studio that I had to put the AP in the middle of to get full coverage since it had floor to ceiling windows facing downtown Seattle and obviously a bunch of interference. I still couldn't get a signal in my bathroom. In our office, we have nine access points for a little over 2,000 sq ft. The microwaves in the restaurants on each side and the lead lined sheetrock (used to be a dentist office) plus the odd shape make it hard to cover. A single AP will not cover a house, much less have plenty of margin like you claim.

    12. Re:While the idea it good. Impractical by bjwest · · Score: 1

      ...Tell that to anyone with a house that is more than 400 sqft.... Wifi has a range of about 100 ft indoors

      Which means the range covers over 30,000 sqft. Now of course your house is not perfectly round, and your access point won't be in the exact center. But there's still plenty of margin to cover a decent-sized house.

      Yeah, right. My house was build in the 1940's. My router is about 40 feet straight line to my bedroom. We're talking three walls between it and me, and I get piss-poor wifi in the bedroom.

      Now granted those three walls do have quite a bit of lumber in them, being 1/2" tongue and grove boards covered in drywall. I'd be willing to bet you could get close to completing two of todays "normal sized" 2400 sq. ft. homes with what's in my 1800 sq. ft. home.

      --

      --- Keep the choice with the user..
    13. Re:While the idea it good. Impractical by drinkypoo · · Score: 1

      A single AP will not cover a house, much less have plenty of margin like you claim.

      I'm using a single AP, and not only does it cover the house, but also most of the yard, and the non-attached addition. And by 'yard' I mean a couple of acres.

      Of course, I live in the sticks, and I don't have a microwave. I can't see any other APs from here, even with the transmit power cranked. So yeah, a single AP will cover a house with no problems at all, if you don't have to compete. This house is built like most houses are (like crap) and the wiring is cheap and sloppy so I wouldn't imagine this is even a best-case scenario.

      --
      "You're right," Fisheye says. "I should have set it on 'whip' or 'chop.'"
    14. Re:While the idea it good. Impractical by sribe · · Score: 1

      Now granted those three walls do have quite a bit of lumber in them, being 1/2" tongue and grove boards covered in drywall.

      You sure about that? I bet they're lath boards (no tongue, no groove), supporting plaster walls (not drywall). And that might be your problem. Typically, when people with plaster walls have wifi problems it's because their walls use metal mesh lath instead of wood strips, which seems not to be your case. But plaster is also substantially denser than drywall, so I suppose that alone could result in some attenuation.

      Anyway, drywall started to replace plaster in the 1950s, so newer homes don't have these problems, and really do get good coverage from a single access point.

    15. Re:While the idea it good. Impractical by bjwest · · Score: 1

      I'm positive about it. I had to cut into a wall to reroute my toilet fill line (old one filled from the top of the reservoir, new ones fill from the bottom). Definitely drywall and tongue and groove boards. There's still tatters of the original fabric wall coverings nailed to the boards.

      Butifull wood, too. Very tight growth rings and zero knots in the couple of square foot section I opened up.

      --

      --- Keep the choice with the user..
    16. Re: While the idea it good. Impractical by Anonymous Coward · · Score: 0

      As an Apple acolyte your house will be cheaply built with paper-thin walls (paper?) and need replacing every 3 years. This is the only way I can think of that you get a 4000 ft^2 house connected with a WiFi-compliant router, because they're not MAGIC.

  6. Going back to smoke signals. by Anonymous Coward · · Score: 0

    It doesn't matter how fast the transfer speeds are when that crippling "direct line of sight" requirement comes into play.

    For getting faster than wi-fi speeds I'm pretty sure plugging in a cable is easier than calibrating beam projectors.

    1. Re:Going back to smoke signals. by Anonymous Coward · · Score: 0

      Why would we need to eliminate the possibility of multiple arcs? We currently are using directed wifi to eliminate the issues of interference, why can't we go the opposite direction to obtain more coverage? We know they showed to arcs with two data rates, and while I admit the 300Gb number is impressive, 100Gbs is nothing to sneeze at, and we could partition the arc of a whole room. The problem will be how to handle moving targets such as cell phones, laptops and tablets.

      Captcha: reputes

    2. Re: Going back to smoke signals. by Anonymous Coward · · Score: 0

      For those who aren't familiar, free space optical systems are used for line-of-sight connections, such as between two buildings. Radio connections to serve comparable bandwidth involve additional costs in spectrum licensing, so FSO systems tend to be cheaper, but they suffer from alignment issues between the transmitters and receivers. This technology could represent a pretty cool step forward for FSO systems. No more alignment pr

    3. Re: Going back to smoke signals. by Anonymous Coward · · Score: 0

      Whups. I'm having problems aligning my fingers with the keyboard - comes of drinking a bottle and a half of wine with a beautiful woman tonight :)

    4. Re: Going back to smoke signals. by Anonymous Coward · · Score: 0

      If you just turn off the screen the picture of the beautiful woman won't distract you any more and it might free up one of your hands. :-)

      Couldn't resist.

    5. Re: Going back to smoke signals. by Anonymous Coward · · Score: 0

      Hahaha! Damn, that's where my other hand was!

  7. O_o by Anonymous Coward · · Score: 1

    I really need 224 gbps internet so I can burn my 350gb cap in 13 seconds.

  8. Pointing is hard by TechyImmigrant · · Score: 1

    This has been done to death. If you concentrate the otherwise omnidirectional signal into a beam, it can get improve snr between sender and receiver and so get higher data rates.

    The problem is not beamforming. We've been able to dynamically beamform for decades. The problem in mobile packet networks like WiFi is knowing in what direction to point the bloody beam. This is not a solved problem. These researchers have not solved this problem. They've invented a better beam former, when the missing piece is the prescient algorithm that can predict where someone has moved since the last packet.

    --
    I should use this sig to advertise my book ISBN-13 : 978-1501515132.
  9. Re: Hooray! Another potential replacement for Wif by Anonymous Coward · · Score: 0

    Meh. I'd rather enjoy WiFi then go live in a shack deep in the woods. If I die earlier, whatever.

  10. Not Possible by JimSadler · · Score: 2

    As a citizen of the United States I know that this technology can not exist. My fellow Americans have long concluded that only the US can have any advanced technology or scientific knowledge. England in particular along with those non bathing French weirdos have never had any non US technology that was worth a hoot. This conclusion is part of respect for American exceptional doctrines which explain that Shakespeare and Chris Columbus were both born in New Jersey and that Christ was born after the Civil War ended.