1.3mi PtP link. Suggestions?

[Frank]

The only problem with NLOS and WiFi that normally the calculations aren't
worth much. I witnessed a group do 125 miles between Nevada and Utah (with
LOS no amps) and 1000' fail with NLOS.

The fact is, you won't know until you try it. I'd suggest going out with at
least two different pairs of antennas of different designs and gains. You'll
want to test the setup with setting to 80.11g and then set to only 802.11b.
B mode has higher sensitivity and power on most radios.

So far, my limited testing of non vertical/horizontal antennas has not shown
any advantage (at least in my test environments, your mileage may vary).


Frank Keeney
Blog: http://www.unwiredadventures.com
Work: http://www.wlanparts.com 
Photos: http://snurl.com/unwirephotos


> -----Original Message-----
> From: Steve Mickeler
> 
> 
> I'm in the planning stages of a 1.3mi link. It's a NLOS 
> situationdue to
> some trees and rooftops.
> 
> I'm planning to use 2 x linksys WTR54GL units running DD-WRT.
> 
> Based on the following calculations, using a 2400MHz Tx frequency, the
> 1.31mi distance, along with a 200mW Tx power, -80dBm Rx 
> sensitivity, 1dB
> loss for connectors and cable, and 14dB antenna gain on the 
> Tx and Rx, I
> get a Theoretical System Operating Margin of 23.5 dB.
> 
> This is using a helical antenna, chosen because it is of a circular
> polarization and according to my research, the best for 
> getting through
> and around obstructions.  Now I may be incorrect on this 
> which is why I'm
> asking here.
> 
> The antenna specs can be found here :
> http://www.wade-antenna.com/Wade/Helical.PDF