Point to point sharing of ADSL connection

I am too far away from my local British Telecom exchange to get ADSL but I have found a willing partner who can get broadband and have been looking at the options to link to his service via a wireless link. We have direct line of sight with a distance of 1.5Km. I am looking at a pair Netgear ANT24D18 Antennae for the purpose. One snag I have hit is that the line of sight goes straight through national grid high voltage electricity lines between two pylons. Does anyone know or can anyone point me to a source of expertise that would tell me if the electromagnetic field around the lines would screw up the wireless transmission? I would hate to buy all the gear for it not to work for this reason!

Reply to
Chris
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David Taylor is in the UK.

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don't think power lines should be a problem.

Reply to
dold

Be sure to do the math necessary to insure that you have a reliable link.

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for a fade margin or system operating margin of about 20dB. Nothing worse than 10dB will work reliably. Your receiver sensitivity will vary with connection speed.

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you sure 18dBi is enough gain? You can get 24dBi from a dish antenna with a narrower beamwidth (for interference reduction) and

12dB more fade margin. Do the math. If you're lost, kindly supply what hardware you have to work with, something about the path, how much coax cable you're going to use, and I'll work the numbers. See:

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an example of how it's done.

Also, be sure to do a site survey to insure that there are no other

802.11 systems around that might interfere, especially if they are along the line of sight between the two endpoints.

You won't have any trouble from the power lines. If you use horizontal polarization, the horizontal power lines will act as less of a barrier. With at 24dBi gain dish, the beam width is about 7 degrees. At 1.5km, that's a 150 meter wide spot. A few cm of blockage by the power lines isn't going to be noticed.

What you may get is some 2.4Ghz RF noise coming from the power lines. There isn't much noise coming from the power lines, but the gain of the antennas will increase its stength substantially. If your system displays highly variable connection loss, it might be noise. It's difficult to see and will require a spectrum analyzer and low-noise amplfier with a big dish antenna to detect. I wouldn't be overly concerned about it as such noise interference is rather rare. However, if something goes wrong, look for it.

Reply to
Jeff Liebermann

Reply to
Chris

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