I could probably find the answer to this by some research, but I'm too lazy. :D We have the beginnings of free wifi in our city (Portland), though it's still spotty, at best, since not all areas of the city are 'wired.' I was thinking about how the nodes only cover about 300' each, then there's obstacles, interference, etc. Why can't they put up one big antenna, like radio stations, and pump out 50k watts, or whatever would be necessary to cover the entire city?
That's ok, because I'm too lazy to research a proper answer.
Are you thinking perhaps of the MetroFi system:
Ummm... we gotta work on the terminology. One does not "wire" a wireless network. I guess "install" might be a suitable substitute. Personally, I prefer to "plant" an access point, since many of mine are hidden inside fake plants, but nobody else likes the term. I'm open to alternatives.
Well, lots of reasons, some of which others have mentioned. 50,000 watts means an AM broadcast band xmitter operating on about 1MHz with a bandwidth of about 9KHz. Wi-Fi is 2,400Mhz, with a bandwidth of about 26MHz, or about 3000 times the bandwidth of the AM station. So, you could use a 50,000 watt AM transmitter to run wireless data, but it would be at the speed of a really slow dialup connection, with only one user for perhaps 100 square miles.
Need reading material on RF theory? I'm too lazy to supply a list but might be able to generate a few buzzwords that you can insert into a Google search.