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EU Communications Networking United Kingdom Wireless Networking IT

TWEETHER Project Promises 10Gbps MmW 92-95GHz Based Wireless Broadband 54

Mark.JUK writes A new project called TWEETHER, which is funded by Europe's Horizon 2020 programme, has been set up at Lancaster University (England) with the goal of harnessing the millimetre wave (mmW) radio spectrum (specifically 92-95GHz) in order to deploy a new Point to Multipoint wireless broadband technology that could deliver peak capacity of up to 10Gbps (Gigabits per second). The technology will take three years to develop and is expected to help support future 5G based Mobile Broadband networks.
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TWEETHER Project Promises 10Gbps MmW 92-95GHz Based Wireless Broadband

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  • Cool. (Score:2, Interesting)

    by Anonymous Coward

    Now I can use my cell data plan for 0.8 seconds at full speed before hitting the monthly cap.

  • by Rob from RPI ( 4309 ) <xrobau@gmail.com> on Thursday January 22, 2015 @05:15PM (#48879387) Homepage

    The higher the frequency, the less penetration of solid objects you have.

    At -that- frequency, it'll work well for extremely short range, indoor, communications. But as soon as you put something even slightly solid, or damp, in the way, the signal will get blocked.

    • by jandrese ( 485 )
      I think this is for tower to tower type communication. I do have to wonder about rain fade on a 95Ghz signal though.
    • by Coren22 ( 1625475 ) on Thursday January 22, 2015 @05:52PM (#48879695) Journal

      From Wikipedia:

      Compared to lower bands, radio waves in this band have high atmospheric attenuation; they are absorbed by the gases in the atmosphere. Therefore they have a short range and can only be used for terrestrial communication over about a kilometer.

      and

      While this absorption limits potential communications range, it also allows for smaller frequency reuse distances than lower frequencies. The small wavelength allows modest size antennas to have a small beam width, further increasing frequency reuse potential.

      It sounds like the absorption will be a feature, not a bug. This will allow many more antennas in a city like situation. It won't be any good in rural areas, but I don't think it is meant for that.

      • by Kjella ( 173770 )

        It sounds like the absorption will be a feature, not a bug. This will allow many more antennas in a city like situation. It won't be any good in rural areas, but I don't think it is meant for that.

        I really don't see it, in the city any point-to-point beam is going to be a lot slower, unreliable and probably more costly than just running a fiber. Wireless for consumers is a different story, people expect their cell phones and tablets and wifi laptops and whatnot to run at higher and higher speeds but this will be useless for that since it can't penetrate buildings.

        Near my cabin in Norway they're planning a fiber rollout now, population density of county is about 35 people/km^2 (92/square mile) or a li

        • It is point to multipoint. So it will be a connection to your cell phone, or someone's internet access.

          Taking the average population density of the US vs other countries is counter intuitive, much of the central US is farmland, mountains or deserts, most of the population is on the coasts, so the density of the cities is much higher than that figure would imply. A better figure would be comparing specific city's population densities, which you would be amazed at with New York, but would find LA or Dallas

    • In addition to penetrating solids the range is challenging (or expensive anyway) just because of limited transmit power levels. Power is important because that gives you your range, your cell phone and home wireless router transmit up to about 1 watt. A 1 watt output solid-state power amplifier at this frequency would cost $5-10k, or at least that was the case about a year ago. This project seems to propose using travelling wave vacuum tube technology which provides lots of drive power (50-100 watts) but

    • The higher the frequency, the less penetration of solid objects you have.

      At -that- frequency, it'll work well for extremely short range, indoor, communications. But as soon as you put something even slightly solid, or damp, in the way, the signal will get blocked.

      Yup. At this frequency, walls and vegetation are essentially opaque to RF. This will be useful for in-room or sub-kilometer line-of-sight deployments. Great for Phoenix (little rain, few tall trees), horrible for Seattle (damp, heavily forested).

      One good thing about hitting 25 GHz or higher is that indoor APs and outdoor APs don't fight with each other the way that they do at 2.4 or 5.8 GHz (lower co-channel interference). So you can have a PTMP or mesh network running in dense areas like New York City.

    • Then I should be able to flip this and say that, if and when I am able to reduce my "body frequency" I can walk through walls

      • by hattig ( 47930 )

        Yeah, but the process of reducing "body frequency" is rather terminal - however ghosts can indeed walk through walls. Interacting with physical matter is a problem though - poltergeists must be able to change their frequency on demand.

    • Hell, even 5GHz WiFi doesn't have enough penetration for full coverage of a three-room appartment (albeit in Germany - no US style cardboard walls here). If my router wasn't dual-band I'd be screwed every time I need to take a dump :p

      90+GHz is going to be pretty much limited to Line-of-Sight unless they have some pretty awesome tricks up their sleeves.

  • by Anonymous Coward

    "MmW" would mean... Mega-metre-Watt. Yes, metric, bitches. There's a method to the madness, and getting it wrong can be disastrous like mistaking " for ' can yield disaster. No, you don't get to complain that it's too hard, for it isn't.

  • The TW in TWEETHER is for a Travelling Wave Tube, which is about the only way to get decent power at mmWave, thus these nodes are not going to be cheap. Why not just use the Ka band backhaul, where you can get soild state PAs, and push it to 4096 QAM, or perhaps the new angular momentum diversity. Is all the bandwidth really eaten up at Ka band, even given the narrow beamwidths?
    • Solid state GaAs is slowly catching up to TWTAs at this frequency. They're not common but it is possible to buy a 30 watt solid state amplifier, probably for the same price you can get a TWTA that has a little bit more power. GaN still has lots of problems at this frequency but it's improving and will likely be competitive with tubes within 5-10 years.

      But yes it seems like it would be much easier to do this at Ka band where solid state amps are now a better value than tubes for communication applications.

      • by rfengr ( 910026 )
        Is it possible to get tens of watts at W-band without spatial power combing or other hairy stuff? I'm doing some GaN load pull right now, but it's no where near W-band.
        • To get tens of watts from solid state in W-band yes you need either spatial or corporate (or both) combining of individual chips. So the amp ends up being of similar size to a mm-wave TWT but you don't need an expensive and large HV power supply or water cooling. Chip level output powers in GaAs I think have been done up to about 500mW, and 1-2W in GaN.

          GaN for mm-wave still has some yield and reliability problems (pick at least one depending on supplier), and performance is not yet up to the ideal levels.

  • Could something like this could completely hose all the ISP's if open sourced and if it works well? Here's the concept: People like the dd wrt folks could customize router firmware to act as repeaters and whoever wants can set up relay stations with home type routers, weatherproofed and sitting on a pole outside if need be, creating a de facto municipal wireless broadband network without needing ISP's. I guess some question are: how to hook it up to the regular Internet's backbone, address space, etc. Could
    • by rfengr ( 910026 )

      Could something like this could completely hose all the ISP's if open sourced and if it works well? Here's the concept: People like the dd wrt folks could customize router firmware to act as repeaters and whoever wants can set up relay stations with home type routers, weatherproofed and sitting on a pole outside if need be, creating a de facto municipal wireless broadband network without needing ISP's. I guess some question are: how to hook it up to the regular Internet's backbone, address space, etc. Could a Gorilla Internet [wikipedia.org] be created with something like this?

      Not really, as the beamwidth on these antennas is 1 degree. You would need multiple antennas aimed at multiple neighbors. This seems strictly point-to-point back-haul.

    • I know some gorillas can stand up [goo.gl], but I don't think they're going to start using the internet any time soon, at least not soon enough that we have to start planning a municipal network for them.

  • ... to displace all the wired high speed rural internet that the US tax payers will be installing.

  • You know, stuff we've had for years, that you can knock up a homemade antenna in about five minutes and have something that can kick a few milliwatts up and over 100km?

    I think this is just a solution looking for a problem.

  • by nullchar ( 446050 ) on Thursday January 22, 2015 @06:47PM (#48880211)

    Which HER am I supposed to TWEET?

  • Exec Sum: Wifi VOIP provider wants more wifi discussion, offers prize to OSS OS devs Android

    General Interest: 802.11i and 802.11s? Sliced Bread? Too power intensive? Conspiracy theories?

    Technocrats: We want x frequencies and why, what comes after i/s, why switching is bad compared to standard cell, why power consumption is bad compared to standard cell, why we don't get two radios/frequency changing radios etc. Who knows, (I love slashdot).

    Legal Beagles/ idealists who avoided this discussion because wi
  • I always post [slashdot.org] to the wrong duplicate article! ~sarcasm

    From my other post:

    According to line 'A' on this graph [wordpress.com], the atmospheric absorption at 95-100 GHz is fairly low, but this graph [wordpress.com] shows that rainfade is an absolute killer. Light rain contributes 1 dB/km, which amounts to losing 20.6% of your signal per km. After 10km, you're under 1% of your original signal.

    Somewhere between medium and heavy rain you cross the 10 dB/km line - you lose 90% of your signal per km. That ventures into 'unusable' territory very

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