On Mon, 31 Mar 2008 19:26:14 -0700 (PDT), wrote:

To be more specific, I was reffering to such designs that reduce the
scale of antennas in at least one axis:
http://adsabs.harvard.edu/abs/2004ITAP...52.1945P
http://ctd.grc.nasa.gov/organization...i-antennas.htm
http://ntrs.nasa.gov/details.jsp?R=362773
http://ntrs.nasa.gov/details.jsp?R=470415
I have seen some of them described as fractal trees, but the
information is relatively scarce.

-SIGH-

I know research is continuing on
this subject and even found some info at a website somewhere but I
can't remember where. Since you probably know more about them than me,
I would appreciate some guidance here too

Hi Robert,

Well, your list of URLs just let the air out of the tires on this ride
into the new century.

"Relatively scarce" information comes from one of several problems:
1. you didn't look hard enough and it is out there;
2. you didn't look hard enough and it isn't out there;
3. you don't have to look at all because nothing new is out there.

That aside, and given you poor usage of efficiency:
Ok, it was my mistake to not clarify 'high efficiency'. By that I
meant 'at the same order of efficiency as normal scale designs'.
"Same order?"

A garden variety dipole in the back yard can be 95% efficient. Now,
what is comparable within the "same order?" 80%? 40%? 20%? 5%?
For the same bandwidth? For the same gain?

Without metrics this topic of "Antenna physical size" is a joke.

73's
Richard Clark, KB7QHC