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Extreme high speed wireless range

  1. Jun 3, 2009 #1
    high speed wireless with extreme range

    I'm trying to find a way to transmit hd video and data over long distances. Thats not the hard part. Hard part is that all connection points are mobile at varying speeds and MUCH longer range than any network I've ever seen. I have enough power to use any amplifyer or antenna but I'm not sure what type to use?

    I have thought of making near point to point with some sort of tracking system (possible gps)?

    I'm also having trouble deciding what type of wireless tech would be best to use (802.x.x)?
    Last edited: Jun 4, 2009
  2. jcsd
  3. Jun 11, 2009 #2
    How long is long?
  4. Jun 12, 2009 #3
    about 15-20 miles.
  5. Jun 12, 2009 #4


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    I seriously doubt that it is possible to transfer HD video over that kind of distance; as far as I know not even WiMAX can do better than a couple of Mbit over 10km; and at 15-20 miles you would be lucky to get a signal at all.
  6. Jun 12, 2009 #5


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    Uh, yeah, this is the sort of thing that entire companies of very skilled engineers spend years doing. It's not something you're going to cook up in your garage, particularly if you need to deal with constantly-changing multi-path distortion.

    No offense, but if you're seriously considering using 802.x you need to go back and hit the books; you don't know much about digital communications.

    - Warren
  7. Jun 13, 2009 #6
    ok thank you.
  8. Jun 13, 2009 #7


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    I saw a demonstration of someone doing this a couple of years ago.

    He was just using standard computer wireless connections at each end but feeding the signal into small (18 inch) parabolic dishes. Transmit power was about 30 mW on 2.4 GHz at each end.

    The distance was about 20 km and he connected to Internet on his computer at work while using a laptop in a park 20 km away.

    However, the dishes had to be precisely aligned and there was a perfect line of sight path.

    So, it is sort of possible, but not if either location is changing or if there is not a good path between the dishes.
    Last edited: Jun 13, 2009
  9. Jun 13, 2009 #8
    If you've decided to obey your country's radio regulations, then technically you probably can't do what you want to do using radio energy. If you don't mind stretching the rules a little, then it ~might~ be doable with enough power. However you'll probably need two separate simplex links so you don't have to switch the power amp in and out according to whether the wireless device is transmitting or receiving. If you have high-tech engineers at your disposal, then other options are laser com (hardly possible for mobile com) and UWB. UWB is an awesome technology. It yields practical channel capacity gains of 1000-fold given the same transmit power. This is mainly because of its immunity to fading, the Shannon-Hartley theorem, and much easier duty-cycle reduction than narrow-band systems.
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