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Japan Network Wireless Networking

Japanese Researchers Transmit 3Gbps Using Terahertz Frequencies 134

Posted by samzenpus from the greased-lightning dept.
MrSeb writes "Researchers at the Tokyo Institute of Technology have developed a new wireless transmission system that works above all currently regulated spectrum frequencies. The new system works at the range of 300GHz to 3THz (terahertz), which is the Far Infrared (FIR) frequencies of the infrared spectrum. That spectrum is currently totally unregulated by any country or standards organization in the world, making it ripe for development of new technologies. So far the Japanese researchers have transmitted data at 3Gbps, but in theory speeds of up to 100Gbps should be possible."
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Japanese Researchers Transmit 3Gbps Using Terahertz Frequencies More

Japanese Researchers Transmit 3Gbps Using Terahertz Frequencies

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  • Gamma Rays (Score:5, Funny)

    by Sigvatr ( 1207234 ) on Wednesday May 16, 2012 @03:17PM (#40020391)
    How soon will it be until Japan begins transmitting gamma rays?

  • Hmmm... (Score:4, Insightful)

    by mcgrew ( 92797 ) * on Wednesday May 16, 2012 @03:19PM (#40020421) Homepage Journal

    Infrared? Not exactly wi-fi. You'd have to be in the same room as the router for this to work. I don't see many practical applications.

    • Re:Hmmm... (Score:5, Interesting)

      by MacTO ( 1161105 ) on Wednesday May 16, 2012 @03:24PM (#40020479)

      Different wavelengths of IR have different properties. Indeed the BBC article notes: "as terahertz waves penetrate many materials as effectively as X-rays".

      • Re: (Score:2)

        by bws111 ( 1216812 )

        But isn't the point of using x-rays for diagnostic purposes is that they only penetrate stuff that isn't dense? Things like walls tend to be dense.

        • But could be ideal for a wireless back-haul, where you are currently using microwave with line of site..

        • Re: (Score:2)

          by h4rr4r ( 612664 )

          Walls are dense? Where?

          The average wall is two half inch think drywall sheets and air. External walls have insulation, but that stuff is designed not to be very dense. Studs are dense, but they are only every 16 or so inches.

          • Concrete is dense by every definition.

            • Re: (Score:2)

              by h4rr4r ( 612664 )

              Very few walls are concrete. Even in office buildings only the exterior walls are likely to be concrete.

            • How many houses have you lived in that were built out of concrete, Vault Dweller?

              • Here in Arizona, most of the houses are built out of concrete. It's called "stucco": it's a thin layer of concrete sprayed on top of some substrate (possibly drywall; these houses are dirt-cheap). Obviously, if you're only interested in networking inside your building that's not a problem, but if you're trying to communicate outside your house the walls will be a problem.

                In other parts of the country, bricks are still pretty popular for exterior walls, even if they're just a facade.

              • Remember his POV, basement walls tend to be concrete.

              • Re: (Score:3)

                by rev0lt ( 1950662 )
                I know some houses that have concrete walls. And where I live, granite houses are pretty common (and they have some internal master walls made of granite). My house is made of bricks and a layer of concrete, and lots of apartments, office buildings and schools are built the same way.

              • Re: (Score:1)

                by Anonymous Coward

                In Brazil, the regular wall of homes and offices are made of bricks. Much denser than regular US walls.

              • Re: (Score:1)

                by Ghaoth ( 1196241 )
                you lot obviously don't live in cyclone (hurricanes) prone areas.

              • Nice Fallout reference, but a very large number of houses in warm areas of the planet are built out of either poured concrete forms or concrete block. It's unusual in the US for residential construction which is nearly always stick frame, but the rest of the world actually builds that way quite a bit.

                In fact pretty much every house I have lived in outside of the US used concrete construction at least for the exterior walls. The interior walls are often concrete as well.

          • Walls are dense? Where?

            The average wall is two half inch think drywall sheets and air. External walls have insulation, but that stuff is designed not to be very dense. Studs are dense, but they are only every 16 or so inches.

            Perhaps in your part of the world, the average wall is like that -- but that doesn't mean that that's applicable throughout the rest of the world. Over here (Cape Town), stuff generally gets built with bricks, and the walls of my apartment are of sufficient thickness that my Desire HD has an extremely hard time picking up the wireless signal from an adjacent room.

            • Re: (Score:2)

              by h4rr4r ( 612664 )

              That's probably because you are holding the phone upside down from being so far south. Try flipping it over.

              Even interior walls are brick? That seems highly wasteful.

              • diversity and taste. that's why there are more options for aesthetics than what purely pragmatic, utilitarian points of view have to offer. it turns out that people will design things all kinds of crazy ways with crazy materials just to stand apart, break the monotony, add value, or serve a particular purpose that is outside of average. yes, interior walls can be brick. in a lot of homes, in a lot of places. stop trying to excuse your assumptions by projecting your ignorance as insults, you look stupid. muc

                • Re: (Score:1)

                  by Anonymous Coward

                  Before modern insulation, double brick houses were cheaper in cold areas.

                • Also concrete construction is simply the norm in many countries. Stick frame construction is superior in terms of thermal insulation, but generally inferior in terms of sound transmission level. Stick frame construction would be quite a bit more expensive in countries that normally use concrete.

              • In north of france, buildings build after the second war are mostly build from red bricks. 2 to 3 bricks wide for structure walls and 1 brick wide for interior walls.

          • Thickness and density are two completely different things.

      • ...most of them being gases...

    • Re:Hmmm... (Score:4, Interesting)

      by heypete ( 60671 ) <pete@heypete.com> on Wednesday May 16, 2012 @03:26PM (#40020509) Homepage

      Infrared? Not exactly wi-fi. You'd have to be in the same room as the router for this to work. I don't see many practical applications.

      It sounds actually quite reasonable for private wireless networks: put a transceiver on the ceiling or an elevated part of the wall and provide high-speed access to network devices in that room.

      Assuming the waves wouldn't penetrate ordinary building materials (though the wikipedia [wikipedia.org] suggests that some building materials are not reasonably opaque to these waves) then one could have the convenience of a wireless network without the security risks involved with longer-range radio waves that can be picked up at much greater distances.

    • You'd have to be in the same room as the router for this to work.

      Sounds ideal, I'll have one in each classroom please!

      • And if you're getting your routers with a government stimulus grant, you can buy top-of-the-line $22,000 Cisco routers for every single classroom too!

    • Media center interconnects. Large rooms, e.g. event centers.

    • Re: (Score:3)

      by dissy ( 172727 )

      Infrared? Not exactly wi-fi. You'd have to be in the same room as the router for this to work. I don't see many practical applications.

      No terahertz is not exactly wifi. Both are blocked by thick metal for example, neither are blocked by wood glass or plastic.

      In fact the only things I know of that will block terahertz which wifi goes through are water and bone.
      If your walls are made of water or bone, then yes you will need to stay with gigahertz frequencies :P

      • " If your walls are made of water or bone, then yes you will need to stay with gigahertz frequencies :P"

        This is an idiotic statement to make. One of the first things you should have learned in science is that damn near EVERYTHING contains water, including rocks... Those wooden walls are holding quite a significant amout of water. That AIR you're breathing has substantial water in it (see humidity). And not to mention things like resonant frequencies of oxygen mollecules...

        With all this stuff absorbing

    • Re: (Score:3)

      by hawguy ( 1600213 )

      Infrared? Not exactly wi-fi. You'd have to be in the same room as the router for this to work. I don't see many practical applications.

      Then you haven't seen how much it costs to wire an office and provide network ports.... *and* keep it neat "Why do those wires have to come down the wall, why can't they go through the floor? Because I'd have to core through 8" of concrete to do that. Well, just do it, it's only money!" (then the same thing happens next year when the cubes are moved).

      If I could hang 4 or 6 of these off the ceiling to provide network coverage to a 40 person open office area, it could be a huge money (and headache) saver. Es

      • Re: (Score:3)

        by hawguy ( 1600213 )

        The article has an even better application of a short-range wireless system that doesn't penetrate walls -- networking for servers in the datacenter. Currently I have a 6 node VMware cluster built from discrete 1U servers with about 60 network interconnects (including intra-cluster communications, but also connections to the core network and SAN network) Ok, so all are 1Gig and it would take a fraction of that in 10Gig connections and a blade center would help too, but the cluster was built before 10Gig wa

    • Re: (Score:2)

      by Ihmhi ( 1206036 )

      Big tower with multiple IR lasers.

      Every roof has an IR receiver.

      We can already align satellite dishes just fine on our own. Now would my idea be any good for the city? Not really. But how about in a rural area where they have a lot of open space and LoS? Sure, the occasional passing goose might get blinded, but hey, free dinner if he crashes onto land!

    • Why does transmission have to happen in the "room", and not, say, "outside the room", to, say, a satellite 50,000 miles away?

      And, why only 3 Gbps??? Check this one out: http://www.irconnect.com/noc/press/pages/news_releases.html?d=118076 [irconnect.com]

      Definitely infrared (THz for some definition of THz) carrier, with up to 40 Gbps datarate, able to go to and from a big router in space...

      In the interest of full disclosure, I have been working on a small part related to that program in my past, so immediately reacted along

    • Single-room apartments are common in Japan. And though I have a multi-room house with computers in other rooms, my main computer and router are in the same room.

  • Also cuts heating costs (Score:3)

    by Orga ( 1720130 ) on Wednesday May 16, 2012 @03:20PM (#40020433)

    as the water molecules contained in the upper layers of your skin move in reaction to these waves!

    • Re: (Score:1)

      by gewalker ( 57809 )

      It will be worth it if you can reheat your burrito without having to walk all the way to the kitchen.

  • I have an ignorant question... (Score:5, Interesting)

    by MobileTatsu-NJG ( 946591 ) on Wednesday May 16, 2012 @03:21PM (#40020447)

    I've heard before that the higher the range of frequency, the harder it is for signals to penetrate things like walls. If we keep advancing along these lines, could this potentially ease our troubles with wifi-over-saturation because we won't be picking up our neighbors' signals?

    • I've heard before that the higher the range of frequency, the harder it is for signals to penetrate things like walls. If we keep advancing along these lines, could this potentially ease our troubles with wifi-over-saturation because we won't be picking up our neighbors' signals?

      I already have trouble get wi-fi through the whole house without multiple APs. You must be living in an apartment or something.

      • Yes, you're exactly right. It happens at my office, too. We have so many hotspots nearby that I have gotten a stability boost by telling it not to auto-change channels.

        Any suggestions on how I might be doing it wrong would be appreciated. This is not my area of expertise.

        • Yes, you're exactly right. It happens at my office, too. We have so many hotspots nearby that I have gotten a stability boost by telling it not to auto-change channels.

          Same here. At any given moment there are literally 35+ wireless networks within range of my wireless devices, so many that the automatic channel-changing was degrading performance because 2/3 of the routers in the building chase each other across every channel all day long. I've actually fired up my wifi sniffing ap on my phone to show people out of pure amusement; watching it in real time is like watching some sort of competitive sport. It's not even just residential signals, either...there is a strip m

        • Re: (Score:3)

          by jandrese ( 485 )
          Well, it's not exactly legal, but you could tell all of your wireless gear that you are Japanese and switch over to channel 14. You'll be stepping on radiolocation beacons, but those shouldn't be around in the middle of a city anyway.

          • Would those radio location beacons be the sort of thing that airports would find useful?

            • Re: (Score:2)

              by jandrese ( 485 )
              No, airport beacons operate on different frequencies, as do maritime ones. I've not been able to find any actual radiolocation devices using that band. There is a patent application for one, but I can't find any examples of one that has been built. The 2.45Ghz band is not a good one for radiolocation anyway, since it is absorbed strongly by water, meaning it will be less effective in storm conditions--which is when you need radiolocation services the most.

    • Yes, you're right. After all, visible-light is pretty damn high-frequency and it sucks at penetrating walls.

      Visible light: 400 to 700 nm
      Far Infrared: 15,000 nm to 1,000,000 nm
      Regular wifi: 125,000,000 nm

      I have no idea at what wavelength drywall and other modern building materials start seriously attenuating a signal (as in "only good for line-of-sight" attenuating). Anyone?

      • Just answered my own question (Score:5, Informative)

        by LanMan04 ( 790429 ) on Wednesday May 16, 2012 @03:34PM (#40020625)

        "Terahertz radiation is non-ionizing submillimeter microwave radiation and shares with microwaves the capability to penetrate a wide variety of non-conducting materials. Terahertz radiation can pass through clothing, paper, cardboard, wood, masonry, plastic and ceramics. It can also penetrate fog and clouds, but cannot penetrate metal or water."

        http://en.wikipedia.org/wiki/Terahertz [wikipedia.org]

        • Re: (Score:1)

          by cdibbs ( 1979044 )
          So it won't work very well in humid environments. "Sorry, boss, the wife took a long shower."

          • It can also penetrate fog and clouds

            So it won't work very well in humid environments.

            Fog and cloud are humid environments.

            • Re: (Score:1)

              by cdibbs ( 1979044 )
              Hah. Missed that, somehow. Nevertheless... depending on the application, I probably wouldn't trust a technology that can penetrate water vapor, but not water, until I learned a bit more about the specifics.

        • Re: (Score:2)

          by jd ( 1658 )

          So it'll be useless in England or the US' Pacific Northwest.

          Although it can penetrate a wide range of materials, that doesn't mean there's zero reflection. I'm much less interested in this for Wifi and much MORE interested in it for building a GPR, since it is essentially illegal in the US for garage developers to experiment with GPR technology (you can't even get the license to operate one unless you've a provable corporate need or are military). If these frequencies aren't regulated, FCC rules prohibiting

          • Re: (Score:2)

            by Nethead ( 1563 )

            Ground Penetrating Radar [wikipedia.org] research? How much power do you need? There are nice chunks of UHF, SHF and EHF frequencies available to hams. (http://www.arrl.org/frequency-allocations) Are there other US TLAs that keep you from pointing you ham antenna at the ground? (CQ CQ CQ DX!) You would just have to incorporate your call sign in your modulation every 10 minutes.

            And regarding PNW rain, Terabeam Free Space Optics [terabeam.com] started in Seattle. I had rackspace in the same colo that they started in (Westin Building.

            • Re: (Score:2)

              by jd ( 1658 )

              GPR is very low power, as transmissions go. The higher-power high-end 2.4 GHz and 5 GHz radars out there can manage 10 feet through soil but typical sets will manage about half that. Although people will talk about GPR not working well when there's water around, I've no particular interest in trudging through muddy fields in heavy rain. That kind of stuff only really affects corporate and military users, where there's very specific time constraints involved.

              My interest is in building GPR systems that are sp

              • Re: (Score:2)

                by Nethead ( 1563 )

                The basic Technician license lets you have full privileged above 50MHz. It's about as hard as getting a food worker permit. The FCC rules for ham are designed for experimentation. They let people use 1.5KW (input, not ERP) to feed gain antennas at VHF/UHF to bounce signals off the moon. I can't recall anything that wouldn't let you pump a few dozen watts into the ground.

                Email me if you need help getting licensed.

                Also note that ham and wifi share some bandwidth, but a ham can run much more power. Some

      • As I recall, drywall never attenuated the noise in the next dormroom very well. This was a pre PC experience however.

        • Re: (Score:1)

          by Anonymous Coward

          Those were low frequency signals. Penetration was the whole point.

    • Re: (Score:2)

      by wfolta ( 603698 )

      The BBC article says, "Terahertz wi-fi would probably only work over ranges of about 10m, but could in theory support data rates up to 100Gb/s - close to 15 times higher than the next-generation 802.11ac wi-fi standard that is under development." So the distance would pretty much limit wi-fi saturation whether its ability to penetrate materials did or not.

    • Re: (Score:2)

      by tlhIngan ( 30335 )

      I've heard before that the higher the range of frequency, the harder it is for signals to penetrate things like walls. If we keep advancing along these lines, could this potentially ease our troubles with wifi-over-saturation because we won't be picking up our neighbors' signals?

      Well, 300GHz+ is considered "light" rather than "radio", so it won't penetrate far through the walls. In fact, it may be a bit inconvenient since the only signal is coming through the open door unless you put in a repeater in the sa

  • How much is that in median tentacle pr0n movie units per second?

  • hehehe, tit (Score:1)

    by Anonymous Coward

    Tokyo Institute of Technology? hahaha, TIT.

  • Riddle (Score:1)

    by Anonymous Coward

    Q: What do you call electromagnetic waves at Terahertz frequencies on the other side of a wall?

    A: Utterly useless.

  • It requires line of sight and only has a range of 1-3 meters without significant power boosting. In other words.....you are better off just running wires

    • Re: (Score:2)

      by jd ( 1658 )

      Since the lower frequencies can pass through rock, it's safe to say line of sight isn't necessary. However, the limited range is a problem and as 100 Gb/s is already achievable by Ethernet (300 Gb/s for Infiniband), it's not clear what the benefit is of adopting a technology that will max out (in the future) at the speeds you can get now, when most of the benefit of wireless really won't apply.

    • Re: (Score:2)

      by JSBiff ( 87824 )

      Seems like it'd be useful for something like a "Wireless HDMI" standard, to allow your computer, phone, etc to transmit HD video to your TV or projector.

  • *reconfigures pirate radio station to broadcast in FIR frequencies*

  • If terahertz wifi cards become generally available, how long before we see articles about people repurposing the hardware to do terahertz reflective imagery like the security guys already do for looking through walls to spot people in a room or look through cloths to see "weapons"?

    http://www.dailymail.co.uk/sciencetech/article-2131932/The-REAL-X-Ray-spex--new-terahertz-scanner-lets-mobile-phones-walls.html [dailymail.co.uk]

  • Major advance, stupid article (Score:5, Interesting)

    by Animats ( 122034 ) on Wednesday May 16, 2012 @04:00PM (#40020921) Homepage

    The real news here is that terahertz electronics is getting small, and potentially cheap. That has many uses. Most of them, though, do not involve data transmission. Terahertz radar will be useful for medical imaging, security, and driverless cars. There will probably be manufacturing applications, like quick 3D profiles of objects for inspection and measurement.

    Point to point terahertz data transmission probably isn't that useful. Point to point laser links have never been very useful. At light and near-light frequencies, rain, snow, and fog will block the beam. If you want one, outdoor laser links are commercially available. [digitalairwireless.com]

  • There they go! (Score:1)

    by Anonymous Coward

    There go the rest of the bees!

    • I think some researchers recently came to a conclusion that bees get wiped out due to widespread use of pesticides and insecticides. We might, of course, plop some bee-sized tinfoil hats and see how that works out :)
  • You might be able to cook a turkey at those frequencies.
  • "Researchers at the Tokyo Institute of Technology have developed a new wireless transmission system that works above all currently regulated spectrum frequencies. The new system works at the range of 300GHz to 3THz (terahertz), which is the Far Infrared (FIR) frequencies of the infrared spectrum"

    Except such frequencies are prone to interference and don't travel far and don't work well when the transmitter and receiver are moving, which means you need lots of base stations.

    "Terahertz wi-fi would probab

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