Hi guys,
I have spent over 25 years testing antennas on antenna ranges.
Everything from the small NBS Gain Standard to microwave parabolic
antennas up to 15 feet in diameter. From 300 MHz to 38 GHz.
I have not seen or read the test comparison that you all are talking
about so I can't make specific comments about the tests.
However, my impression of all the tests based on the comments
in this thread in this
N.G. is that these tests are like the story of the mouse trying
to describe an elephant by feeling around the part of the legs of
the elephant that he can touch.
An antenna is a three dimensional animal. It radiates in all
directions , some better than others.
There's only 2 things you can do:
1. decide which plane is most important to you and
measure it in that plane.
2. or measure it all planes.
IN hf communications where we utilize skywave, the angle of
arrival is variable. How can you possible say that this antenna
or that antenna is better when you've only measured it in one
plane ???
It seems to me that the zero elevation is the least important
plane in which to measure these antennas. How many of thhese
antennas are used to receive signals where the signal comes in at
zero elevation ?
Saying that all these antennas patterns are the same is not
related to the real world.
Every antenna has it's own signature, the pattern. THey don't
even reproduce from one antenna to another.
When we published antenna patterns, they were a combination of 5
antennas meaured at low end of the band, the center of the band
and the high end of the band.
Unless you can compare at least this data (3 d , a number of
antennas of the same model, and multiple frequencies) I maintain
you can't make a reasonable or fair comparison.
--
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