Thread: Image theory
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Old January 7th 07, 08:24 PM posted to rec.radio.amateur.antenna
Gene Fuller Gene Fuller is offline
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First recorded activity by RadioBanter: Jul 2006
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Default Followon to image theory

David wrote:
Various books claim that a ground plane reflects the radio wave emitted by
the vertical, and then claim that a ground plane is formed or simulated by
four elevated radials.


[big snip]

David,

The images in these cases are not real. That's why they are called
virtual. However, real or not, these images can provide useful
assistance in simple determination of the expected radiation patterns.
Like most models, the image model has limitations. Some applications
will succumb to image modeling more readily than others.

Bottom line: There is no real conflict among the experts. Image modeling
is generally quite easy. If the results make sense, be happy. If not,
then try more complex methods. I would expect all of the experts to
agree that detailed mathematical modeling is required for the best
accuracy unless the image model has unrealistic parameters such as
infinite extent, perfect conductivity, etc.

73,
Gene
W4SZ