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Old August 14th 07, 12:39 AM posted to rec.radio.amateur.antenna
nx7u nx7u is offline
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First recorded activity by RadioBanter: Oct 2006
Posts: 13
Default Patch antenna Polarization?

Yes to both.
A corner-fed patch is roughly circularly polarized...I say roughly
because there are some other pertubations typically made to force the
sense of the CP, and also to improve the circularity.
But if the feed is just offset a bit (like 1/4-3/4 rather than
1/2-1/2)...well that should act similarly to an offset-fed dipole, so
you'd have higher input impedance and some feedpoint reactance. And
the pattern linearity would be more elliptical (patches typically have
relatively high crosspolar response anyway).


Ok, to make sure I understand;
If I put the feed on the lowerhalf of the patch the antenna would be
vertically polarized?
And, if I put the feed on the left or right half of the patch the antenna
would be horizontally polarized?
Now to complicate things, I see some patches split the difference and put
the feedpoint on the left side of the lowerhalf. What does that do?
Thanks, Mike