>> I've heard of sufficiently excited people getting distances in 
>> excess
>> of 100km with 802.11,

> Show me two of those excited. They need cold water.
> There are a few problems with transmission:
> - for 100km it must be stright line, direct visibility and good
> wheather = almost impossible, now you have Wilma's interferencies.

What he says.
And, to get range you need good antenna height at both ends and 
significant clearance in between. This is to provide that line of 
sight path above the curvature of the earth and to avoid "Fresnel 
Zone" problems due to interference with phase shifted reflected 
signals. (Google knows).

Ranges of 100 km are technically achievable but in addition to the 
above you'll want an excellent antenna at each end (probably a largish 
parabolic), as much power as you are (possibly not) allowed (although 
aerial considerations usually swamps power limitations), low loss and 
short feed lines and good equipment. Alignment becomes crucial with 
high gain aerials. Then pray for no rain or operate in eg Arizona - 
there's an excellent reason that microwave ovens share the same 
frequency band :-).




        RM 

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