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Old February 14th 07, 04:18 PM posted to rec.radio.amateur.antenna
Jerry Martes Jerry Martes is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 173
Default Antenna Axial Ratio RHCP LHCP


"art" wrote in message
ups.com...
On 13 Feb, 22:18, "Jerry Martes" wrote:
"Bobby" wrote in message

ups.com...

All,


How do you determine the axial ratio from a RHCP wave to a LHCP wave
from an antenna? In essence, I need an axial ratio transformation from
RHCP to LHCP.


Any ideas on the equation or where I can find it will be helpful.


Thanks.


Bobby.


Hi Bobby

If you are working with an antenna that radiates RHCP it is totally
insensitive to LHCP.
If you have an antenna that radiates "RHCP" (or LHCP) the axial ratio
is
the ratio of the Minor axis to the Major axis of the E field. So, it
varies from zero to one as the radiated field varies from Linear to
Circular.

Jerry


You mentioned insensetivity above, are there any other polarities
insensitive to others ? I note that weather antennas are now migrating
to
dual diversity antennas for horizontal and vertical, is it possible to
totally isolate those too.?
Art



Hi Art

I may make mistakes by using non scientific terms. When I read my post,
I realize that nothing is actually defined by my above statement. I would
submit that a LHCP antenna will receive no RHCP signal. I'm sure you know
that any linearly polarized antenna is insensitive to linearly polarized
signals that are orthogonal to the line of polarity of that antenna.
Tell me more about the "weather antennas". What frequency do they use?
Where do they transmit from?

Jerry