[aprssig] Helix Groundplane?
Robert Bruninga
bruninga at usna.edu
Tue Dec 11 18:49:37 EST 2007
> Helix antennas being circulary polorized have
> rejection to the opposite rotation generaly
> caused by reflections provided that both...
Wow, interesting. I just realized then, that the "reflector
screen" at the back of a Helix is not adding any gain then.
Because it is true, that any reflected energy will be the
opposite circularity! Thus it cannot add in phase to the direct
wave.
I guess all the ground plane is doing is providing a
counterpoise for the feed system. Oh, and possibly a degree of
attenuation to ground noise... Both well worth the metal, I
guess. Comments?
Bob, WB4APR
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