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View Full Version : multipath analysis in Pathloss



saslin
2010-08-04, 09:02 PM
Hi,

I have 15 km long MW link at 13 Ghz over the water surface (sea), as you can see in attached screen shots, which is often experiencing some sort of fade. Could someone please explain this documents, or give me guidance have to make this multipath analysis in Pathloss ? Thanks!

http://rapidshare.com/files/410972204/Multipath_040810.png
http://rapidshare.com/files/410972372/link_profile_040810.png

byja
2010-08-05, 07:13 AM
Hi,

I have 15 km long MW link at 13 Ghz over the water surface (sea), as you can see in attached screen shots, which is often experiencing some sort of fade.

Not the explanation, but a simple advice to counter multipath fade in this situation, which could help.

First of all make sure that your antennas are properly alligned. I had a case where guys alligned the antennas so that they're actually looking not at each other but at reflection of the antenna over water surface.

Second, once you've made sure no. 1 is checked, try uptilting (change the elevation angle of the antenna so that it looks up into the sky a bit) both of the antennas so that you loose a decibel on each side. You'll loose 2 dBs, but fading should be decreased more.