No - it IS the polarization of the far field signal resolved as separate
horizontal and vertical components.
Take a look at the two components for a hexbeam as predicted by EZNEC:
http://www.karinya.net/g3txq/temp/hexbeam_vandh.png
Note the shape of the vertically polarized (red) component.
Now take a look at the actual MEASURED azimuth response of a hexbeam,
using a vertically-polarized sense antenna:
http://www.karinya.net/g3txq/temp/hexbeam_vpolarisation.png
The "skew" in the vertically polarized component is caused by
common-mode current in the vertical coaxial band interconnects; I was
making the measurements to understand the effect of alternative choke
positions.
It demonstrates how careful you need to be when trying to plot radiation
patterns. Depending on the polarization of the sense antenna, you can
achieve quite different results. You would have to combine the results
from a vertical and a horizontal sense antenna to produce the "normal"
EZNEC "Total Field" plot. You also need to take care to avoid
common-mode current on the sense antenna feedline if you want to be sure
what you are actually measuring.
Steve G3TXQ
Larry Banks wrote:
> If memory serves me well -- that is simply a vertical or horizontal cut
> through the plot 3D plot. It is not the polarization of the field.
>
> 73 -- Larry -- W1DYJ
>
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