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Wireless Networking

German Researchers Hit 40 Gbps On Wireless Link 104

Posted by Unknown Lamer from the don't-stand-in-front-of-it dept.
judgecorp writes "German researchers from the Fraunhover and Karlsruhe institutes have achieved 40Gbps transfers over 1km using a wireless link. The new record raises the hope that point-to-point wireless could be used instead of expensive fibers in some rural broadband applications." Partially thanks to transmitting between 200GHz and 280GHz.
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German Researchers Hit 40 Gbps On Wireless Link More

German Researchers Hit 40 Gbps On Wireless Link

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    • Re:2 obligatory questions (Score:4, Funny)

      by Anonymous Coward on Tuesday May 21, 2013 @04:23AM (#43779631)

      Here's another obligatory question

      3. How many Australian Luddites care about what's happening in Germany?

      Enquiring minds want to know

    • Re: (Score:3, Insightful)

      by Anonymous Coward

      1. How the hell is this going to fare in a real world test where a metropolis of people oversaturates the frequency?

      What part of "point to point" did you not understand?

    • Re:2 obligatory questions (Score:5, Insightful)

      by ikaruga ( 2725453 ) on Tuesday May 21, 2013 @04:45AM (#43779695)

      1. How the hell is this going to fare in a real world test where a metropolis of people oversaturates the frequency?

      From the summary.

      ...used instead of expensive fibers in some rural broadband applications

    • Re:2 obligatory questions (Score:5, Informative)

      by Anonymous Coward on Tuesday May 21, 2013 @04:52AM (#43779713)

      The higher the frequency, the more like light. It is a highly directional transmission, so unless there is another source of 200-280GHz signals within a few degrees of the transmitter sending in the direction of the receiver, there's not going to be interference.

      When somebody tells you that fiber is a waste of money, ask them if we should stop building those expensive roads as well, because we can all fly helicopters instead.

      • yeah but helicopters are expensive compared to cars. I'm fairly certain that this setup is cheaper than the amount of fiber its replacing.

        • yeah but helicopters are expensive compared to cars. I'm fairly certain that this setup is cheaper than the amount of fiber its replacing.

          Give this man a cigar!

          Hopefully it will not rely on any "proprietary" tech so it can't be priced at $5 million per radio or, (cost of building fiber - 10%).

        • The issue is that this is only going to be replacing a single fiber. You never run a single fiber except short loops to your endpoint customers. This could potentially replace the point-to-point links for the "last mile", until such time as you get enough subscribers to make it worth your time to trench the land and run a bundle of fiber.

    • Re: (Score:2)

      by Chrisq ( 894406 )

      How many Australian luddites are going to look at this say that the national fibre-optic broadband network rollout is going to be made obsolete by this wireless tech?

      A 1km range is next to nothing for rural Australian

      • A 1km range is next to nothing for rural Australian

        For Texans, 1 mile is "neighbors" . . .

        . . . 100 miles is "just down the road" . . .

        . . . 1000 miles is "just down the road, aways" . . .

        • Re:2 obligatory questions (Score:5, Insightful)

          by niftydude ( 1745144 ) on Tuesday May 21, 2013 @07:04AM (#43780111)

          A 1km range is next to nothing for rural Australian

          For Texans, 1 mile is "neighbors" . . .

          . . . 100 miles is "just down the road" . . .

          . . . 1000 miles is "just down the road, aways" . . .

          Heh, I know people in the US like to think Texas is big, but the truth of the matter is that the area of the state of Texas is just under 700 thousand sq km, while the area of the state of Western Australia is a bit over 2.5 million sq km.

          That's about 3.5 Texii*.

          * I know - Texii probably isn't the correct plural for Texas, but Texases just sounded wrong.

          • Aye, I spent some time with family up "near" southern cross, "near" kalgoorlie, where the nearest house was around 200km away. Go bush around here, and distances get epic.

            • Go bush around here, and distances get epic.

              . . . which is probably way off the rural scale in Germany, where the system was developed.

              Folks in Germany see Australia on TV as a place where B-celebrities are sent to eat nasty looking creepy-crawlers and bathe in kangaroo poo. And then whine and bitch about each other to see who gets to stay the longest.

              So how does one stay connected in southern cross . . . ?

          • Re: (Score:2)

            by Shatrat ( 855151 )

            There is no correct way to pluralize Texas, there can be only one Texas. Anyway, just because Australia or Alaska or Siberia are larger, doesn't mean Texas still isn't a big place. You can drive from Beaumont, Texas to Los Angeles and by the time you're halfway there, you're still in Texas.

            • Re: (Score:2)

              by drkim ( 1559875 )

              You can drive from Beaumont, Texas to Los Angeles and by the time you're halfway there, you're still in Texas.

              This doesn't mean anything. You could say that New Mexico is bigger than Texas by saying, "You can drive from Farmington, New Mexico to Odessa, Texas and by the time you're halfway there, you're still in New Mexico."

          • So, you got one large province, which has some pretty big empty expanses. But, being from Canada, I'd have to say you have nothing on us. And We probably having nothing on Russia. I mean, the Sakha [wikipedia.org] state/province consists of over 3 million square kilometers. They also have Krasnoyarsk Krai [wikipedia.org] which is 2.3 million square kilometers. And the size of the country is over 17 million square kilometers. Canada and Australia on the other hand both have much lower population densities than Russia.

          • Re: (Score:2)

            by Krojack ( 575051 )

            Are they planing on supplying Internet Porn to the Australian outback tribes or something? =)

        • Re: (Score:2)

          by dbIII ( 701233 )
          In rural Australia 100 miles is "neighbors" :(

          • Re: (Score:3)

            by Chrisq ( 894406 )

            In rural Australia 100 miles is "neighbors" :(

            Please don't mention Australia and neighbours [neighbours.com] in the same sentence. Now I have that terrible signature tune going through my head.

    • Re: (Score:2)

      by bmo ( 77928 )

      The question really is, why are there so many kangaroos in Austria?

      --
      BMO

      • Re: (Score:2)

        by drkim ( 1559875 )

        The question really is, why are there so many kangaroos in Austria?

        --
        BMO

        Because kangaroo marriage is STILL illegal in the USA.

        • Re: (Score:2)

          by bmo ( 77928 )

          But if we legalize kangaroo marriage, people will be marrying their furniture!

          We don't want that now, do we?

          --
          BMO

          • Re: (Score:2)

            by drkim ( 1559875 )

            But if we legalize kangaroo marriage, people will be marrying their furniture!

            We don't want that now, do we?

            --
            BMO

            That ottoman LIES! That stain is from leather polish.

            • Re: (Score:2)

              by bmo ( 77928 )

              I heard you talking sweetly to the ottoman. I thought you were on your cellphone, but then I saw the bluetooth earpiece on the kitchen counter.

              Fess up!

              --
              BMO

              • Re: (Score:2)

                by drkim ( 1559875 )

                I heard you talking sweetly to the ottoman. I thought you were on your cellphone, but then I saw the bluetooth earpiece on the kitchen counter.

                Fess up!

                --
                BMO

                Yeah.. the kitchen counter asked if it could make a booty call to the lawn chair.

    • 1. How the hell is this going to fare in a real world test where a metropolis of people oversaturates the frequency?

      You do realize they said *point-to-point wireless could be used instead of expensive fibers in some rural broadband applications*, right? How many rural metropolises do you know of?

  • ...for RIAA, SACEM and the like...
    • Offtopic? This is not a secret that RIAA and the like are not investing any effort in building faster infrastructures ( quite the opposite ). If history was made based on their whims, we'd still be using vinyl records, without even a cassette to make a copy... At 40Gbps, a HD movie is copied within a second...

  • Does anyone on /. know if any studies have been done to determine if all of this ever-increasing 'wireless' energy we are putting out has any significant effect on warming our environment?

    I am not trying to be chicken little here, but the thought just occurred to me seeing this summary.

    • Re: (Score:1)

      by Anonymous Coward

      It has more or less the same effect as the same amount of energy put into wired solutions. In other words, the only relevant question is how it affects total energy consumption.

    • Re:Serious question.... (Score:5, Informative)

      by Anonymous Coward on Tuesday May 21, 2013 @05:02AM (#43779745)

      Wireless LAN access points send at less than 1W (much less, depending on the regulatory domain), which is eventually converted to heat. Your brain on the other hand turns more than 10W of chemical energy into waste heat and you have only that stupid comment to show for it.

    • Your average wifi antenna radiates 100mW.
      Doing some very rough calculations in an hour that will heat a litre of water by about 0.08 degrees Celsius assuming that the water can't lose any heat to its environment.

      Compared to say 2000 Watts for a microwave that does cook food with 'wireless energy'.

      Also compare that with just the temperature from your car's engine and exhaust gasses.
      I think the latter wins hands down.

      • Re: (Score:2)

        by rts008 ( 812749 )

        Thanks for the info.

        I figured it was probably not a problem, but did not really know.

  • on the link quality. I'd bet a light mist will halve the throughput.

    • FTA: "According to researchers, the atmosphere shows especially low attenuation in this frequency range, and the technology has already been tested with distances over one kilometre."

      Does not say if this includes in rainy conditions, since you're right that - normally - the higher the freqency the more it is impacted by atmospheric moisture.
      Still, you get TV and your cell phone works when it rains...

      • Yeah, but the 2.4 GHz band goes through walls and humans easily. 240 GHz is a different story. 50 GHz already has trouble getting through on a rainy day, 240 GHz won't do much better. You'll need some insane receivers for this thing.

    • Re: (Score:2, Insightful)

      by Anonymous Coward

      The important facts are missing from both the summary and the English article. The german original has more info:

      http://www.kit.edu/visit/pi_2013_12950.php [kit.edu]

      Basically, the important news is that they build new send/receive integrated chips that can be feed directly a optical link, transmit over radio waves and on the other side feed directly back to optical (fibre).

      Formerly, you either have to:

      * transcode from optical to radio link, and back on the other side, which is expensive (extra components), draws more

    • Re: (Score:2)

      by dbIII ( 701233 )
      Microwaves attenuate in wet weather due to the wavelength being close to the length of the hydrogen-oxygen bonds in water. This stuff has a different wavelength so it might go through mist as if it isn't there.

  • Those frequencies are probably affected just as much by rain and fog as optical, and pretty much as directional. You can easily get multiple Gbps systems off the shelf.

    • Re: (Score:1)

      by Anonymous Coward

      this can be usefull for tower-to-tower comunication. the last mile can be 3/4G or even wifi.

  • Fraunhofer not Fraunhover (Score:1)

    by Anonymous Coward

    Has nothing todo with hovering ;)

  • Bad naming in summary (Score:1)

    by Anonymous Coward

    For those not wanting to read TFA:
    It's two institutes: The Fraunhofer Institute for Applied Solid State Physics and the Karlsruhe Institute for Technology. Karlsruhe is a city, not an institute.

    • Re: (Score:1)

      by Anonymous Coward

      Not enough fun is made of the University of Karlsruhe for renaming themselves Karlsruhe Institute of Technology to create a mental association with the Massachusetts Institute of Technology.

  • Not good for long haul use (Score:5, Interesting)

    by Muad'Dave ( 255648 ) on Tuesday May 21, 2013 @06:55AM (#43780093) Homepage

    This band is not useful for long haul carriage due to atmospheric water vapor absorption. According to this chart [eoportal.org], absorption between 200 and 280 GHz varies between 3 and 40 dB/km. That means at the low end only 50% of your signal is absorbed every km. At the high end, only 1/10,000th of your signal remains after each km.

    this post [slashdot.org] speaks to similar issues including refraction.

    • Re: (Score:1)

      by Anonymous Coward

      Easily solved. Just use RF waveguides between the repeaters. The wavelengths at the given frequencies would be a bit larger than 1 mm, so the waveguides would be about the size of fiber optic cables.

      Uh ... wait ...

    • Re: (Score:2)

      by xtal ( 49134 )

      They're not proposing using this for longhaul - although, there are lots of longhaul microwave links. You design for the fade margin and availability you need taking into consideration the rain fade. No big deal. These issues are common to all microwave links.

      The point of TFA, and the exciting thing about this technology is it provides a way to do last mile distribution potentially to homes, in a multi-gigbit class. If the manufacturing cost goes down, this does provide a interesting solution to the distrib

      • Designing a microwave link below 50 GHz where the path loss is at most 0.2 dB/km is MUCH easier than designing one that can range from 3dB/km to 40dB/km. For every km of path, 37dB of dynamic range/headroom is a factor of around 5000x (closer to 5012, actually). If you need 1W to achieve your desired S/N ratio in dry air (3dB loss) over 1 km, you'll need 5kW when it's raining. Make that 2 km and you go from needing 2W (6dB loss) to needing 50 MW (yes, megawatts at 80dB loss).

        Even if the required signal leve

    • This band is not useful for long haul carriage due to atmospheric water vapor absorption. According to this chart [eoportal.org], absorption between 200 and 280 GHz varies between 3 and 40 dB/km. That means at the low end only 50% of your signal is absorbed every km. At the high end, only 1/10,000th of your signal remains after each km.

      this post [slashdot.org] speaks to similar issues including refraction.

      That has not and will NEVER stop $TELCO from selling services across this with "UP TO" marketingspeak which means "we fuck you royally for a service which is online but effectively unuseable".

  • shouldn't we be investing research into subspace communications? Seems to me that would be the next logical step forward

  • Given the standards organizations' propensity to drag things out (802.11n anyone? [wikipedia.org] (7 years)) This is nice from a research perspective but probably years away from having practical equipment you can use.

    Why not FSO [wikipedia.org], or microwave? Running wireless at long distances has already been done. http://en.wikipedia.org/wiki/Long-range_Wi-Fi [wikipedia.org] If you look at that long range Wi-Fi link, those are some substantial distances. Sure, not 1Gbps but they work.

    I have a customer with an openWRT setup running 802.11a at 1/2 mi

  • German researchers from the Fraunhover and Karlsruhe institutes have achieved 40Gbps transfers over 1km using a wireless link.

    Technicians from the German Telekom immediately showed up to cap the link to 300kbps due to excessive use of bandwith...

  • Limits and caps [nytimes.com] at 75GB unless you pay a lot more. "Former" monopoly Telekom owns a hell of a lot more than just that last mile of copper.

    The article is a puff piece which ignores the massive amount of data lost through connection drops, forced restarts & reloads YouTube and many other sites cause/require, as well as the ever-increasing bandwidth necessary due to "cloud" services, software-as-a-service, growing page programming/scripting and third-party & indirect loads (predictive actions, agents

  • you are not going to have massive range at 200 and 280 GHz
  • I've aimed microwave STLs before and that was a royal pain in the ass. In the hundreds of gigahertz range aiming the antennas has got to be a bitch. And damn well better make sure the mast and mountings will never shift under wind pressure.

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