Our workgroup had been seeking a low cost temporary solution for a point-to-point link to an offsite facility. We needed greater than 10Mbps throughput and thought 802.11a wireless might offer some promise.
At the present moment (June 2002) no manufacturers offer low-cost devices with detactable antennae. This significantly limits range of 802.11a to around 300 Meters under the best conditions. Directional antenna are needed to focus the send/receive energy at further distance.
Inspired by the work of Rob Frohne and his Primestar Wireless Antenna Page - http://www.wwc.edu/~frohro/Airport/Primestar/Primestar.html . I decided the solution was to integrate the low-cost Access Point, directly into an obsolete PrimeStar TV Dish.
After a little experimentation and engineering (the feed horn is a particularly important component). I found that simple modification of a US standard aluminum soda can would work. I obviously have a few mounting and water-proofing details the work-out.
Much to my shock, It Worked!!! I was able to get to the end of my test range easily (~1000ft), and my latop was registering 60% signal strength and 24Mbps connectivity. Now onto the actual installation...
I guess that the side-to-front gain is around 9-10db. The large area of the Primestar dish seemed to help pick-up the much lower energy laptop card well (I had tried previously with a Dish Network dish).
 A rough design of the feed horn, a sode can is 2.5inches, a bit too big. |  Cut top off can, cut antenna hole 0.6" from end |  Netgear HE102 ready to install. OBTW, the foil also helps one ground the can, which is needed. | |||||
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 Fully outfitted PrimeStar Dish ready for testing... |  My test range, I am limited to around 1000ft. |
June 29, 2002 Dean Eckstrom
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