I believe there are limitations on antenna gain and total EIRP in those frequency bands which would make it difficult - if not impossible - to get any kind of link budget over that distance. I could be wrong, but that's my reading of 47 CFR Part 247(I think that's the correct citation). David Leonard ShaysNet On Thu, 16 Aug 2001, Leo Bicknell wrote:
On Thu, Aug 16, 2001 at 11:01:54AM -0500, Cerqua, Toby wrote:
client needs 45Mbps pushed over 20 miles... and he wants it wireless. the kicker is that they don't want a T3 because it is "too expensive" and it would take too long to get installed. it doesn't need to be constant, but he wants to move of 2.5GB within 45 minutes. this is in the chicago area, if that helps any. so, i don't know, satellite?
802.11a might do what you need. Not sure if it has been standardized yet, but if not there are a number of proprietary implementations in the same speed range. It promises 50Mbps with similar properties to 802.11b.
20 miles is going to be a long throw, but not outside the range of possibilities if you have line of site and good rooftop acesss. You will need some big antennas though. A site in the middle making it 2 10 meg shots would be ideal.
-- Leo Bicknell - bicknell@ufp.org Systems Engineer - Internetworking Engineer - CCIE 3440 Read TMBG List - tmbg-list-request@tmbg.org, www.tmbg.org