Some more thoughts on how wirelss works.
They install a radio transciever on light polls in the nieghborhood in a checkerboard grid pattern. Takes 5 minutes to install, non obtrusive, no ditches, no line crews.
Imagine a checkerboard and the black squares as the radio units. Each square has 4 other squares cadicorner to it for a path. Now imagine another checkerboard above that one, sort of like that chess game in the old Star Trek. That represents the top of the spectrum. i.e. the lower checkerboard is 800 MGHZ and the upper one is 900 MGHZ. In between you have all the frequencies in that range. (btw the number are made up for this example, I don't know the actual frequencies off hand. Anyway as you can see the path to one of the 4 cadicorner checkerboards is very broad. This is your basic "spread spectrum" design. What this allows is for a clear path to always be avaliable, even if one of the transmitters fail, it still works, because there are 3 more transmitters in range.
The other feature is security. If your transmission starts at 800 MGHZ and there is a clear path along that frequency, the system will not follow 800 the whole way. In one leg it will be 800 and in the next it will be 850 and so on. It also varies your starting frequency. Thi makes it very secure, since anyone "listening in" will only catch a packet or two on a particular frequency. You can see the military influence here, which is where this all got started.
Scott
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