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Google Tests White Space Spectrum For School Broadband In South Africa

Posted by Soulskill on from the spread-cat-pictures-far-and-wide dept.

judgecorp writes with news that Google is beginning tests on white space spectrum to deliver broadband internet access to rural communities in South Africa. "White space has the advantage that low frequency signals can travel longer distances. The technology is well suited to provide low cost connectivity to rural communities with poor telecommunications infrastructure, and for expanding coverage of wireless broadband in densely populated urban areas. ... Ten schools in the Cape Town area will receive wireless broadband to test the technology. During the trial, we will attempt to show that broadband can be offered over white spaces without interfering with licensed spectrum holders. To prevent interference with other channels, the network uses Google’s spectrum database to determine white space availability."

33 comments

  1. Damn it, Google by Anonymous Coward · · Score: 5, Funny

    White space, huh? Is Google bringing apartheid back to South Africa!?

    1. Re:Damn it, Google by idunham · · Score: 0

      You got it backwards.
      They're using it to benefit the blacks, which must mean desegregation.

    2. Re:Damn it, Google by flyingfsck · · Score: 1

      Well, the white having to make space, is part of black empowerment.

      --
      Excuse me, but please get off my Pennisetum Clandestinum, eh!
    3. Re:Damn it, Google by Sigg3.net · · Score: 1

      No no. It's only white Lebensraum for our signals...!

      --
      Defining Statistics and Social Research
  2. sounds like... by Myself337 · · Score: 2

    They have something to prove to the FCC. I for one welcome our low cost wide range broadband overlords.

    --
    I'm poor. Please donate. http://albanypcs.com
  3. Microsoft already doing it in Kenya by PineHall · · Score: 2, Informative

    Microsoft is already using a whiite space network in Kenya to bring 16Mbps broadband powered by solar panels to towns without electricity.

    1. Re:Microsoft already doing it in Kenya by Anonymous Coward · · Score: 0

      That's just fabulous, for Kenya. Personally, I could use a little bit of that high-tech sort of broadband connectivity right here in central Missouri. Do you realize just how badly dialup sucks? My spell checker doesn't even know that word "dialup". Sheesh.

    2. Re:Microsoft already doing it in Kenya by Anonymous Coward · · Score: 1

      That's it, I'm moving to Kenya.

    3. Re:Microsoft already doing it in Kenya by crutchy · · Score: 0

      Microsoft now owns the Kenyan government

      Kenya is now just a Microsoft subsidiary, and Ballmer can use Kenyans to alpha test all future versions of Windows

    4. Re:Microsoft already doing it in Kenya by Anonymous Coward · · Score: 0

      Only in Kenya!

      http://www.weebls-stuff.com/songs/kenya/

  4. DIgital people never learn by Ol+Olsoc · · Score: 2
    Tropo Ducting

    Meteor burst

    General propagation

    Most digital people seem to think that all frequencies act the same, or in this case, lower frequencies travel farther than higher frequencies.

    Some even seem to think that Bandwidth is infinite.

    This project smacks of BPL, (Broadband over Power Line) who's promoters seemed to think that you could impress Radio signals onto Power lines without interference to other services, and other services would not interfere with BPL..

    The lowest Television channels, in the VHF portion of the band, are known as the "magic" band by Amateur radio operators, because the frequencies some times act like much lower frequencies, with long distance propagation, and some times like higher frequencies, with strictly line of sight distances. And there is noise also. The old school TV stations used a lot of power for a reason. Get that signal to noise ration as high as possible. And a meteor burst noise is going to disrupt digital immensely, and they happen all the time.

    What ever could go wrong? There is a reason why those Gigahertz frequencies in use work for wireless. They are much more quiet, they specifically have much shorter range, which keeps everyone from interfering with everyone else, and the bandwidth is inherently higher at those higher frequencies. Look up Shannon's limit, and spare me the phase modulation infinite bandwidth bs, because the bandwidth become infinite - but the power need is also infinite. This is probably a Government Grant make some money for failing trick.

    --
    The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
    1. Re:DIgital people never learn by Anonymous Coward · · Score: 0

      Yes, many people seem to think the laws of physics don't apply when talking about radio frequencies. And many of them seem otherwise intelligent!

      I suspect the governments will fall prey to companies wanting to sell hardware that will use those frequencies, and then those governments will eventually have to rent or purchase other frequencies to get clear channels for what those frequencies used to be used for. Or maybe they'll just have to purchase back all those devices they allowed to be sold.

    2. Re:DIgital people never learn by crutchy · · Score: 1

      i'm pretty sure BPL was only limited because of transformers being in the way

      BPL works fine for LAN within a home or business

    3. Re:DIgital people never learn by tlhIngan · · Score: 1

      This project smacks of BPL, (Broadband over Power Line) who's promoters seemed to think that you could impress Radio signals onto Power lines without interference to other services, and other services would not interfere with BPL..

      BPL tried to use a bunch of frequencies modulated over the power line. Of course, BPL proponents never considered that power lines were excellent antennas. That resulted in interference to the airwaves. This is a problem as power lines are NOT shielded.

      The lowest Television channels, in the VHF portion of the band, are known as the "magic" band by Amateur radio operators, because the frequencies some times act like much lower frequencies, with long distance propagation, and some times like higher frequencies, with strictly line of sight distances. And there is noise also. The old school TV stations used a lot of power for a reason. Get that signal to noise ration as high as possible. And a meteor burst noise is going to disrupt digital immensely, and they happen all the time.

      What ever could go wrong? There is a reason why those Gigahertz frequencies in use work for wireless. They are much more quiet, they specifically have much shorter range, which keeps everyone from interfering with everyone else, and the bandwidth is inherently higher at those higher frequencies. Look up Shannon's limit, and spare me the phase modulation infinite bandwidth bs, because the bandwidth become infinite - but the power need is also infinite. This is probably a Government Grant make some money for failing trick.

      Except that "white space" uses unused TV channels. A vast swatch of the VHF and UHF spectrum has been allocated to TV. Since not everywhere has all channels in use (most places probably are lucky to have single digits channels available OTA), that gives a wide swath of unused spectrum available. White space won't interfere with 6m or 2m or 440 operations because TV isn't there.

      Indeed, it's why white space is trialed outside of the US - the FCC has been trying to encourage white space development, but the problem is stepping on legitimate broadcasters. Proposals have included a GPS database (Google has agreed to host it), but the problem is how to bootstrap it - a fixed database will get old quickly (and products may sit on shelves or unused). And you need a data connection to get an update. And you can't just blindly transmit because it could interfere when you try to get the update.

    4. Re:DIgital people never learn by s122604 · · Score: 1

      They did not say they are using VHF low. They are most likely using VHF HI (>175 MHZ), or UHF frequencies between 400-700MHZ.
      These frequencies are in a "sweet spot", traveling much better than > 2GHZ signals and don't get hammered by Sporadic E, Meteor scatter or other weird propagation effects as much as lower frequencies.

      Although from TFA, the hop they are doing is 6.2 miles. With decent towers and highly directional antennas on both ends, 2.4ghz could work.

    5. Re:DIgital people never learn by Ol+Olsoc · · Score: 1

      i'm pretty sure BPL was only limited because of transformers being in the way

      BPL works fine for LAN within a home or business

      also/quote> What the issues with BPL were was that running the signals along the power lines acted as an antenna. Not a good antenna, but an antenna none the less.

      The digital signal is a radio frequency wavelength signal, So it can escape from the line. Other signals can get into the line, also.

      Hams regularly communicate around the world on HF with microwatts of power.

      In tests, a one watt signal into a loaded whip at around 27 MegaHertz would shut adow all BPL for blocks around, imagine Ham radio operators who typically transmit at 100 Watts or more. and the BPL interfered with licensed services even though they used notch filters to keep the digital signals away from those services. I believe th eproblem was intermod, with two signals mixing to create a third, something else digital engineers often don't know.

      It was basically a bad idea championed by people who didn't understand RF.

      --
      The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
    6. Re:DIgital people never learn by Ol+Olsoc · · Score: 1

      Although from TFA, the hop they are doing is 6.2 miles. With decent towers and highly directional antennas on both ends, 2.4ghz could work.

      And there you have it. One other thing that they might not have thought about is that longer distances automatically limit th dnumber of channels you can use. That short range is a big plus.

      --
      The shepherds did so well protecting the flock that the sheep no longer believed that wolves existed.
    7. Re:DIgital people never learn by Sigg3.net · · Score: 1

      Also, African elephants make excellent wifi APs!

      According to BBC elephants communicate long distance by thumping (yeah, like Dune). Add that to the mesh network controller and you're all set!

      --
      Defining Statistics and Social Research
  5. In other news... by TankSpanker04 · · Score: 4, Informative

    Looks like Microsoft is doing basically the same thing in Kenya:
    http://arstechnica.com/information-technology/2013/03/solar-power-and-white-spaces-bring-internet-to-towns-without-electricity/

  6. White Space? by dohzer · · Score: 1

    Doesn't the specific white space they are using determine its long-distance performance, not just the fact that no one is currently using that frequency band?

  7. Frequency? by quenda · · Score: 1

    TFA is short on detail. TV whitespace could be anything from 40MHz to just under the 850 and 900 MHz bands widely used for cellular internet connection.

  8. Re:YOU IFAIL IT! by Anonymous Coward · · Score: 0

    is there at least a female version of this?

  9. won't that f up all the elephants by Anonymous Coward · · Score: 0

    just postin for the heck of it, but don't the elephants use that space ?

  10. Google spectrum database by manu0601 · · Score: 1

    How is Google spectrum database fed? I did not find the information on their site.

    1. Re:Google spectrum database by flyingfsck · · Score: 1

      Uhm, with a RF spectrum analyzer?

      --
      Excuse me, but please get off my Pennisetum Clandestinum, eh!
    2. Re:Google spectrum database by ve3oat · · Score: 1

      If they are setting up communications transmitters in a foreign country, shouldn't Google be asking that country's national telecommunications administration which channels are clear to use and which are not? It probably never occurred to Google that every country in the world has its own version of the U.S. FCC, and for the same reasons that the FCC exists, that is to regulate such things as frequency allocations, exact channel assignments, transmitter powers, emission bandwidths, etc etc. Many countries have different regulations than the U.S.

    3. Re:Google spectrum database by manu0601 · · Score: 1

      You mean they deployed sensors everywhere in the US?

  11. Why not a tower? by evilviper · · Score: 1

    Here's a crazy question... Are the lower (white-space) frequencies really worth all the efforts? We're talking about UHF TV frequencies here, which generally only go up to 60 miles, really only slightly beyond line-of-sight (VHF can do quite a bit better). Outside of heavily wooded forests and dense urban cities, how much benefit are they getting out of these frequencies, versus needing to site their WiFi antennas better (ie. higher up), or having twice as many base stations repeating the signal?

    Is the benefit of slightly better range with the lower frequencies really worth buying custom equipment, rather than commodity $35 off-the-shelf APs? Neither the stories on Google or Microsoft's efforts with this tech actually say a non-trivial amount about the tech.

    --
    Slashdot gets worse every day... Pipedot: News for nerds, without the corporate slant
    1. Re:Why not a tower? by redneckmother · · Score: 1

      Here's a crazy question... Are the lower (white-space) frequencies really worth all the efforts? We're talking about UHF TV frequencies here, which generally only go up to 60 miles, really only slightly beyond line-of-sight (VHF can do quite a bit better). Outside of heavily wooded forests and dense urban cities, how much benefit are they getting out of these frequencies, versus needing to site their WiFi antennas better (ie. higher up), or having twice as many base stations repeating the signal?

      Is the benefit of slightly better range with the lower frequencies really worth buying custom equipment, rather than commodity $35 off-the-shelf APs? Neither the stories on Google or Microsoft's efforts with this tech actually say a non-trivial amount about the tech.

      From what I've read, the primary advantage of using white space (802.22) is provisioning sparsely populated areas without building expensive point to point infrastructure. I have high hopes for the technology(ies). My only available 'net connectivity is via satellite (blech!), with its high latency, low throughput, punishing data caps, and unreasonable expense.