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Old June 8th 07, 03:51 AM posted to rec.radio.amateur.antenna
Richard Clark Richard Clark is offline
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Default Real time proof of Poyntings vector

On Fri, 8 Jun 2007 01:44:06 +0100, "Mike Kaliski"
wrote:

As a result of searches into gaussian antennae, it quickly became apparent
that commercial versions of these devices are being manufactured for use at
GHz frequencies.


Hi Mike,

Your research would be evidence of substantial "prior art." However,
all previous contexts suggest otherwise and your research bears no
relation to the topic - as described to this point by Arthur.

These designs all seem to use modified horns as the
transmitting element.


This fairly cements the disconnect.

I have not yet found a device made up of discrete
elements. At these sorts of frequencies, discrete element lengths may well
be all pretty much the same dimensions.


Well, I have a Radar background too, and horns are hardly resonant and
are more designed for a match without fringing effects. To accomplish
this they deliberately employ a sweep of dimensions, not one single
but replicated dimension as is suggested by Arthur's descriptions.

I suspect equilibrium may not be the
right term to use but resonance is obviously not quite right either.


Equilibrium has long been a term of vague parentage. Resonance is
hardly a tripping point until you come to phase relationships. As
phase is the name of the game in gain/directivity, and multiple phase
relationships even more; then resonance occurs for at least one
element. However, it is not always necessary as revealed with
Rhombics which are non-resonant but exceedingly directional. Resonance
is more a desirable attribute for feeding the antenna. The upshot of
it all is that your last statement reveals how nebulous the topic is.

Arthur
may be unwilling to give out too many details of his antenna, perhaps
because he wants to protect any future patent application. I inferred the
spread spectrum usage from the types of communication links that are being
developed for wi-fi and other links at these super high frequencies.


As antenna design is scaleable, application defines what is needed,
not what is possible.

I do
not make a distinction between directivity and gain because I believe that
the term 'gaussian' essentially implies a single transmission lobe.


This would suggest that your research (noted above) led you to
geometric descriptions of lobe attributes. Arthur has never used the
term Gaussian in that sense. If he had, it would be distinct from
Lambertian - another term unused which again draws the distinction
away from geometry.

Arts' antenna may be built and may perform as he predicts. If it doesn't
then we will all have learned from the experience whatever the outcome. That
is the principle of scientific advancement.


Standard modeling programs have been proven robust in this regard. The
Status Quo has been maintained throughout. No surprises yet.

73's
Richard Clark, KB7QHC