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Cantenna as Dish Feed

As with the USB dongle parabolic, you can use the cantenna design as a feeder for significantly higher gain. Mount the can on the parabolic with the opening of the can pointed at the center of the dish. Use the technique described in the USB dongle antenna example (watching signal strength changes over time) to find the optimum location of the can for the dish you are using.

By using a well-built cantenna with a properly tuned parabolic, you can achieve an overall antenna gain of 30dBi or more. As the size of the parabolic increases, so does the potential gain and directivity of the antenna. With very large parabolas, you can achieve significantly higher gain.

For example, in 2005, a team of college students successfully established a link from Nevada to Utah in the USA. The link crossed a distance of over 200 kilometers! The wireless enthusiasts used a 3.5 meter satellite dish to establish an 802.11b link that ran at 11Mbps, without using an amplifier. Details about this achievement can be found at www.wifi-shootout.com

Last Update: 2007-01-24