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Old January 30th 10, 11:43 AM posted to rec.radio.amateur.antenna
Richard Fry Richard Fry is offline
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First recorded activity by RadioBanter: Jun 2006
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Default Remarkably Small Antennas - Fact or Fiction

On Jan 29, 7:57*pm, Roger wrote:
The metamaterial
makes the antenna behave as if it were much larger than it really is,
because the antenna structure stores energy and re-radiates it.”
Conventional antenna designs, Holloway says, achieve a similar effect
by adding bulky “matching network” components to boost efficiency, but
the metamaterial system can be made much smaller.


So far nothing has been written about the radiation resistance of this
"1/50-wave" antenna.

Even if the design eliminates the feedpoint Xc of this electrically
small radiator at the operating frequency, its radiation resistance
could be expected to be miniscule, because the Rr of a radiator
depends on the electrical wavelengths it exposes to space.

The claim that it radiates 95% of the power applied to it may be true,
but needs to evaluated with the radiator as part of an r-f system --
where with very low Rr, much of the available power can be subject to
very high losses before it reaches the radiator.

RF