Freifunkblog

The workshop of Christiane Rütten und Sven Dortmund (German) to build a simple Wi-Fi antenna using household materials is now also available in English at heise uk. As in the German version the authors included an antenna calculator in the article. Thanks also for including a link to the global freifunk newswire!

Who'd have thought that a toilet-brush holder, of all things, would turn out to be an excellent Wi-Fi antenna? The lesson is that you can achieve great results for little expense - and half an hour's work. (15.4.2008, http://www.heise-online.co.uk/networks/Build-a-Wi-Fi-radio...) ...

If the access point is three rooms further on, or even in the house on the other side of the road, you need a directional antenna. If you have to make a connection to your nearest DSL-equipped acquaintance at the other end of the village street, or to bridge even longer radio links to reach the free radio node in the next block but one, you may even require two directional antennas. ...

The simply made tin-can antenna, with the dimensions given here, is suitable for base stations and for clients who transmit on 2.4 GHz in accordance with the IEEE 802.11b and 802.11g standards. 802.11a uses the 5-GHz band, requiring different antenna dimensions. The necessary background for a recalculation is given in an article on building tin-can radio antenna (Building a Wi-Fi Antenna Out of a Tin Can)

Very recent base stations that comply with the draft standard 802.11n also use the 2.4 GHz band. But they automatically use a number of methods to combine their antennas for optimal range and speed. However, this only works if the antennas have the characteristics expected by the WiFi chipset. (15.4.2008, http://www.heise-online.co.uk/networks/Build-a-Wi-Fi-radio...)