question about ranges?

[Feyr]

ok here's the deal, we are looking at installing a wireless lan into some desert place (literally :P), that lan needs to have at least a 2 miles coverage around the antenna (or antennas if we need to). also the operating conditions are pretty low (-40 F). everything is pretty much line of sight there, scattered buildings in a small community. i'm not too sure about the power restrictions (canada) and even then the target might have more rights (indians, you never know) about what they can do over RF frequencies. as i said too it's pretty desert, so there's not really a problem with interferences

what we're wondering is, what kind of hardware do we need? this is to set up some kind of mini ISP (in replacement of a cable modem system, since we're not about to lay out our own cables under the permafrost).

we've found some 12 dbi omni antennas, would that be enough? (the antenna is gonna sit atop of a building, maybe with a few feet of extra lenght if needed but not too much as the winds are also pretty strong). is there a chart somewhere we can use to figure out the range?

beside the antenna and an access point for the central, what do we need to install? is there any kind of special routers?

on the end user side, do we need big antennas too? or just a smaller ones would do? all of these will be static, so maybe it would be more cost effective to lay out multiple smaller access points acting as repeaters?

and finally on the software side, can we have all this set up under linux? i'd rather not have to buy a windows license and use pcanywhere to admin this remotely

eh weew, long post :P thanks in advance

[MoleStrangler]

You will have to use more than 1 Access Point to cover this distance.

(1)

'-40' You have to remember that moisture in the air can cause major problems with the signal, 2.4GHz has real problems with moisture;

o Snow
o Rain
o Humidity

I can only guess that you maye have to test in the worst of weather conditions. I suspect that if you have a white-out then the link will not connect.

So you will have to use some 19Ddbi (if legal) to do a number of point-to-point links to a number of buildings to project the network. Then additional Access Points to provide coverage.

You WILL have to create building-to-building links with dedicated wireless links to puch the network furhter. from there you can lay Etherenet in a building and either connect another Access Point or wired PCs and printers.

(2)

You do not say anything about the clients, but generally they do not have good antenna and (with the cheap ones) do not offer an option for larger antenna.

I suspect that you will be stuck with a 0dbi antenna which will further restrict the range.

(3)

Another major problem you will have is the snow on the ground. 802.11 does not go very well over water.

I cannot explain it but it does not.

(4)

The problem with repeating (though possible) is that it adds latency between the end-stations. Some applications are very sensitive to delay and anyone on the end of multiple repeated links may get a lot of kick-outs.

Most companies limit wireless-hops to 3 for this very reason. Combined with the weather conditions your range will be vastly reduced and may be forced to use lots of wireless-hops.

Something that you have to test as well.