Hi Graham:
F.Y.I., WIMAX is using the 5ghz band in Europe. Most antennas are outside and running low power less than 4 watts erp. Wimax systems are usually installed in Dense cites or densely populated residential areas.
I installed a 5 Ghz system in Marousi (Athens Greece) a few years ago. From 1 tower I was able to provide 2-mbit speeds at a distance of 10 kilometers and cover the whole city with just 1 tower.
I used 6 (60-degree) antennas to get a full 360 pattern. I also placed each antenna on a different channel (I used the whole band). The antennas installed at the houses were similar, running less than 1-watt erp. I was also able to get a Wimax LOS detectable signal to the Island of Agena (45 km) from my Marousi tower, if I had another dish, I could have had a useable signal all the way to the island.
Since these antennas are aimed horizontally and trees suck up 5 Ghz, their useful range is usually limited 5-10 km from each tower. Anyone living near one of these towers (usually in a city) will have issues with listening to satellites. A good directional satellite dish will block most of the offending signals.
Wimax frequencies 5.725-5.850 Ghz bands
Take care, Miles WF1F
,
--- On Sun, 4/12/09, Graham Shirville g.shirville@btinternet.com wrote:
From: Graham Shirville g.shirville@btinternet.com Subject: [amsat-bb] Frequency advice requested To: amsat-bb@amsat.org Date: Sunday, April 12, 2009, 7:54 AM Hi all,
AMSAT-UK is involved with the development of a "C Band" beacon to be deployed on a satellite in low earth orbit sometime during 2012. The satellite is ESEO - The European Student Earth Orbiter and the beacon will be part of an amateur package which will also include U/S and U/V linear transponders.
The beacon has to be somewhere in the 5830-5850MHz part of the band as this is the allocation that is available for space to earth transmissions. So the question is - what would be the best part of the band to use - taking into account existing ground equipment and antennas (if any) and potential QRM from other terrestrial systems.
Any ideas or suggestions will be most welcome!
thanks
Graham G3VZV _______________________________________________ Sent via AMSAT-BB@amsat.org. Opinions expressed are those of the author. Not an AMSAT-NA member? Join now to support the amateur satellite program! Subscription settings: http://amsat.org/mailman/listinfo/amsat-bb