Antenna (and to an extent RF theory): The ARRL Antenna Book

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HTH,
Curt

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"Jeff Liebermann" <jeffl@cruzio.com> wrote in message
news:c2d0e3d6u6ajko21v9mb4187iegk63srg6@4ax.com...
| sillyputty <karmictaragem@2die4.com> hath wroth:
|
| >I could probably find the answer to this by some research, but I'm too
| >lazy.
|
| That's ok, because I'm too lazy to research a proper answer.
|
| >We have the beginnings of free wifi in our city (Portland),
|
| Are you thinking perhaps of the MetroFi system:
| <http://www.metrofi.com/content/maps/mf_portland_map_ad.html>
|
| >though it's still spotty, at best, since not all areas of the city are
| >'wired.'
|
| 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.
|
| >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?
|
| 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.
|
| --
| Jeff Liebermann jeffl@cruzio.com
| 150 Felker St #D http://www.LearnByDestroying.com
| Santa Cruz CA 95060 http://802.11junk.com
| Skype: JeffLiebermann AE6KS 831-336-2558