On Thu, 03 Sep 2009 23:01:30 -0500, tom wrote:

http://802.11junk.com/jeffl/antennas/isotropic/index.html

Nice. The 3d pic is impressive.
tom
K0TAR

Thanks, but the design is not mine. I think it came with a 4NEC2
samples collection, MiniNEC, or possibly with one of the other antenna
modeling packages. I've got them all muddled together so I can't
easily determine the source. I don't think I made any changes to the
model. Mostly, all I did was package the results into something
presentable on a web page. (Note: I tried to convince Ari to add a
web page creation feature to 4NEC2, but failed).

Incidentally, I has some illusion of using the isotropic approximation
antenna as a gain reference antenna. I know there are other reference
antenna designs that are more suitable, but I thought it would be an
interesting exercise. I also built one for 2.4GHz, which was a total
failure.

Drivel: Isotropic antenna patents:

"Spherical antennas having isotropic radiation patterns"
http://www.google.com/patents?id=--I2AAAAEBAJ

"Isotropic antenna system and notebook computer"
http://www.google.com/patents/about?id=M2UOAAAAEBAJ
Using multiple antennas to get a reasonably hemispherical pattern on a
laptop.

"Omnidirectional isotropic antenna"
http://www.google.com/patents?id=VQcYAAAAEBAJ
Uses a microwave lens fed by wavguide. Pattern is roughly
hemispherical.

"Near-isotropic low-profile microstrip radiator especially suited for
use as mobile vehicle antenna"
http://www.google.com/patents?id=wNE5AAAAEBAJ

"Near isotropic circularly polarized antenna"
http://www.google.com/patents?id=saMgAAAAEBAJ

etc.... plenty more found with a search for "isotropic antenna". Of
course, isotropic antennas don't really exist. Therefore all the
patents must be science fiction.

Incidentally, I'm still scratching my rapidly depilating head about
your answers to my question about antenna resonance. However, I wanna
do some more reading before demonstrating my ignorance on the subject
and making a fool of myself. Real-soon-now.

--
Jeff Liebermann
150 Felker St #D http://www.LearnByDestroying.com
Santa Cruz CA 95060 http://802.11junk.com
Skype: JeffLiebermann AE6KS 831-336-2558