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1KM 802.11b @ 2MB

Posted by Hemos on from the if-you-build-it,-your-costs-will-fall dept.

OffTheRack writes "Check out this web site to see how a guy in Egypt built his own line-of-site (H:Get? It's Punny.) 1KM broadband connection. Plenty of nice pictures." Pretty cool set-up.

13 of 271 comments (clear)

  1. Cancer by DarthWiggle · · Score: 5, Funny
    I wonder if the great scourge of the twenty-first century will be runaway cancer rates with all the RF radiation we're pumping into the air. Cell phones, LOS broadband, radar, radio...

    I feel my children growing third arms, though they be but little swimmers in my special place.

    1. Re:Cancer by DarthWiggle · · Score: 5, Funny
      No thanks. I'll just go to the quiet zone in West Virginia... er... hang on...

      *looks at crotch*
      *looks at map of West Virginia*
      *looks at crotch*

      Nevermind.

  2. Interference by gpinzone · · Score: 5, Interesting

    Although I live in a small-ish town with presumably little electromagnetic interference, it is worth mentioning that this high-gain, 3 meter tall GSM network monstrosity is located about 7 meters away from my AP antenna, on the same roof. I really can't tell whether or not it is affecting my antenna.

    I think the more important question would be, "Is your unlicensed amplified antenna affecting their transmissions"

  3. amazing by satsuke · · Score: 5, Insightful

    amazing - a site that has all

    Clear text
    Clear reference links
    adequate pictures
    interesting topic matter

    and no popups or ads

    Sounds like the internet around 1995 .. when you could use lynx and download individual gifs and view them without problem ..

  4. He should try this by t0qer · · Score: 5, Interesting

    http://trevormarshall.com/biquad.htm

    I read direct TV dishes are a lot easier to build and go alot further.

  5. Lightning by Leebert · · Score: 5, Funny

    I sure hope they don't get serious electrical storms in Egypt, or this fellow may find himself with a big problem on his LAN.

  6. Like a true geek... by Pollux · · Score: 5, Funny

    After who knows how much time spent on planning and building the project, he finally gets it working, much to his delight: ...these antennae from the start looked as if they meant business, and indeed they did, because as soon as they were installed and properly aimed, they produced a 2Mbps signal at 1km distance. Hurrah! Me do download at home quicky-quicky now!

    But, like a true geek,

    Future mods:

    I am beginning to suspect that my choice of coca-cola cans as reflectors on the Yagi antennae may be affecting signal quality (hence the maximum speed of only 2Mbps). Hence I am looking for a flat-based can that has the same diameter as the coca-cola can.

    It works! It's perfect! Now let's take it apart merely for the sake of making it faster!

    I guess "quicky-quicky" just isn't quick enough.

  7. 1km? No biggie. by 4ginandtonics · · Score: 5, Interesting

    Linksys outputs 50mw. If you were to go to the FCC regulation maximum of 100mw (1 watt), you would do better.

    If you use Cisco's Wireless Calculator Excel spreadsheet, you will see that a 21 dbi parabolic dish (as seen here could grant you 76.1 kilometers.

    Now you have problems with this distance. Line of sight, for one.

    The common calculation calls for a cone shaped space from each antenna meeting at the middle. This is called the Fresnel Zone The calculator says that this zone, for 76km is 28.2 meters (92 feet). So, you have to have 92 feet of clearance. No trees. No buildings. Nothing.

    At this distance (44.5 miles) The earth curvature is 90 feet, somehow your signal must peak over that!

    So, you are going to need antenna heights of over 150 meters to set up a 802.11b wireless like of this long.

    Most engineers say this is simply not feasable. Other issues, such as antenna alighment, water (nasty multipath bounce), WiFi hotspot interferance, and the actual time it takes for a signal to travel that far are issues as well.

    So just remember line of sight. If you have clean line of sight to the other endpoint, and clarity through the Fresenel Zone, you might just have a chance for point-point 802.11b wireless.

    Cheers!

  8. Re:1km? No biggie. by Lord_Slepnir · · Score: 5, Informative
    If you were to go to the FCC regulation maximum of 100mw (1 watt), you would do better.

    not to nitpick, but is it 100mw or 1 watt....100 mw = 0.1 w

  9. 2Mb not 2MB by nihilogos · · Score: 5, Funny

    And as everybody knows you get more chicks if you can tell the difference.

    --
    :wq
  10. Hmmm . . . by CleverNickName · · Score: 5, Funny

    Am I the only person who glanced at this headline and thought that Slashdot was posting headinlines in leet?

  11. How I'm spending MY night by blitzoid · · Score: 5, Funny

    This guy has a page hit counter at the bottom of his page, it's quite funny to refresh it and watch it go up extremely fast. 45845... 45900... and so on.

    --
    I am a filthy pirate.
  12. Wow! I got Slash-Dotted! by HassanAdly · · Score: 5, Informative

    Hello everyone,

    Stop! I can't take all this attention!

    Anyway I wanted to shamelessly use this opportunity to post some comments:

    Since I wrote that article my network has improved significantly. I now use proper N-connectors and RG213 cable, and I've got some links at about 5km now. I now have ten nodes installed, including one AP with a 9dbi omni.

    All my AP's survived the summer and winter with no problems, the oldest units have been up for more than a year now.

    If anyone is wondering how well the WAP11 deals with heat, they would be interested to know that last summer we had 47degC temps, and besides the operational nodes staying up, I left a WAP11 in my car. When I got to it it was warped and melted - but it worked anyway!

    I never expected this kind of attention, else I would have updated my article.

    Thanks everyone for the comments and emails!

    Regards, Hassan