Learn, hack!

URL

http://dewy.fem.tu-ilmenau.de/CCC/22C3/audio/mp3/22C3-1078-en-wifi_long_shots.mp3

File name

22C3-1078-en-wifi_long_shots.mp3

File size

23.7 MB

MD5

0327b9973274702105b0bfb9bb71629c

SHA1

c678b9c690d23f7a7fba25bc62083fe6635ce70e

What you need to know to successfully design and build a wifi long shot. RF Calculation. Knowledge about the Fresnel Zone. Polarisation of electromagnetic waves. Tricks to avoid interference. Timeout problems of 802.11abg and how to deal with them. What you need to know to successfully design and build a wifi long shot. RF Calculation. Knowledge about the Fresnel Zone. Polarisation of electromagnetic waves. Tricks to avoid interference. Timeout problems of 802.11abg and how to deal with them. Slightly more comprehensive description: Wifi is a really inexpensive way to build datalinks up to 120 kilometer distance. Such use of Wifi is already relatively widespread in developing countries that lack communication infrastructure. The world wide web is so far not truly for everyone - may 1 billion people use it and about 5 billions don't. It maybe unavailable, too expensive or both. Indeed, Information needs to be free - that also means that there must be cheap ways to share it. So far WiFi is the cheap way to go where no infrastructure exists - although that may change with WiMax in the future. Even if you live in a developed country it is fun or may be necessary to build your own (community) network beyond the range a few hundred meters.