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Old Feb 11, 2011, 08:54 AM
IBCrazy is offline
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Engineer for Christ
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Amherst, VA
Joined Jun 2006
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Cloverleaf modification

Ok, now I see. I am a bit confused right now. It appears a 3 lobe wheel is more efficient and has better SWR than a 4 lobe. Circularity appears distorted. I thought it would need the ground plane to acheive proper SWR, but apparently that is not the case. The rejecting characteristics are bizzarre! Look at the horizontal plane! I based the 3 lobe design on the wheel antenna that uses a flat lobes .2 wavelengths away from ground and just bent up the sides for circularity.

Looks like I need to try this new antenna. I got an SWR of 1.2 from my skew planar wheels. Now to a 3 lobe cloverleaf, I might actually get 1.1 or better! Element length appears to be 5% longer than calculated wavelength. Compensating for 70% humidity, I'm guessing this drops to 3% or so.

So the comparisons:

Cloverleaf: 1.3 dbic forward, 9-20 db rejection, SWR = 1.2
Skew planar wheel: .92 dbic forward, 12db rejection, SWR = 1.3
CPOD: 1.72 dbic forwar, 19 dbic rejection, SWR = ?

Now the problem... How in the world am I going to make this one easy to build???

-Alex
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Last edited by IBCrazy; Feb 11, 2011 at 09:01 AM.
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