The polar orbiting NOAA weather satellites have right hand circular helical antennas for the VHF APT service. Right hand circular polarization is recommended for NOAA APT receiving antennas.
http://www.noaasis.noaa.gov/NOAASIS/pubs/Users_Guide-Building_Receive_Statio ns_March_2009.pdf
See the section on ground station antennas, p. 45
Grant Zehr AA9LC
-----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of Graham Dillabough Sent: Saturday, October 27, 2012 3:58 PM To: [email protected] Subject: [amsat-bb] Polarization for ISS and Weather Satellites
I haven't posted here in a very long time. I hope this works.
I am building two Quadrifilar Helix antennas (from QST, August 1996); one for weather satellite experimentation, and one as a backup antenna for an upcoming ARISS contact.
I haven't found anything in the ARRL antenna book, or on the web, that specifically says that one mode (RHCP or LHCP) of circular polarization is better than the other for either of the two applications noted above.
Any insight or experience with polarization issues with the ISS and weather satellites are appreciated. The last time I did an ARISS contact, I was plagued with very deep fades, and want to do better this time.
Thanks, Graham
Graham Dillabough, VE6KJ, VO1DZA
Albert Einstein, when asked to describe radio, replied:
"You see, wire telegraph is a kind of a very, very long cat. You pull his tail in New York and his head is meowing in Los Angeles. Do you understand this? And radio operates exactly the same way: you send signals here, they receive them there. The only difference is that there is no cat." Albert Einstein (1879-1955)
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