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https://www.satsig.net/cgi-bin/yabb/YaBB.pl VSAT technology and installation >> Dish pointing and alignment >> Ka rain fade https://www.satsig.net/cgi-bin/yabb/YaBB.pl?num=1363006390 Message started by tearepa13 on Mar 11^th, 2013 at 12:53pm

Title: Ka rain fade
Post by tearepa13 on Mar 11^th, 2013 at 12:53pm

I was told not so long ago that Ka band is above the frequencies an oscillating rain drop impacts on RF namely for Ku band at about 10-20Ghz (for the rain drop) and therefore is not a huge issue. I haven't been converted on that theory however thought I'd bring it to your attention, see if you'd like to comment.

Title: Re: Ka rain fade
Post by USN - Retired on Mar 11^th, 2013 at 6:08pm

Statement is not false, but true only in context. Rain fade is a function of wavelength. Ka-band is of a higher - therefore shorter - wavelength than is Ku-band. Big rain drops attenuate lower frequencies, small rain drops attenuate higher frequencies. So it simply depends upon the prevalent precipitation characteristic in your location.

//greg//

Title: Re: Ka rain fade
Post by Oasis Networks on Mar 12^th, 2013 at 7:38am

Adding my drop of water as well :)

It depends as well on the elevation of the dish.

Think of what Greg mentioned above and you will figure out why...

Just a quick search in Google, I found out this very nice and comprehensive document:

https://www.philsrockets.org.uk/Rain%20Fades.pdf