Date: Wed, 15 Dec 2010 15:41:15 -0500
From: "Craig Clark" <jcclark@myfairpoint.net>
Subject: [TowerTalk] Fractal Antennas, Chip Cohen (N1IR
Fractal Antennas, Chip Cohen (N1IR) Summer 1995 Communications Quarterly
Magazine
http://rfdesign.com/mag/508RFDSF1.pdf
Craig Clark K1QX
Radioware
PO Box 209
107 Fitzgerald Rd
Rindge NH 03461
603 899 6957
www.radio-ware.com
## I read a Scientific American article about fractal antenna's 10 yrs ago.
It was touted as being able to have a super narrow
azimuth beam-width. The idea here was to be able to have the ability to
RE-USE cell freqs over and over and over..all at one
cell site! IE: the touted fractal cell ant was split into dozens of lobes,
each only a few degree's wide. The claimed 3db down points
were the eq of a jillion ele's on a conventional yagi. I read through the
Scientific American article several times..and the maths just
didn't add up. One of the techs at the Telco I worked at for 34 years had
brought in the magazine and was ranting on about it, like
it would solve all our problems at work. There is only so much radio spectrum
for cell freqs, hence the digital cell sites have shorter
range, and more cell sites are required. Then the freqs can be RE-used.
The buck roger's Fractal claims were sci Fi borderline
pseudo junk science imo. Fractal claimed the SINGLE cell site, with it's
dozens of segments could track a moving vehicle... and
as the vehicle moved from one segment to the next, the 'Processor controlled
system' would transparently..'hand off' the moving
vehicle from one segment to the adjacent segment... all on the SAME FRACTAL
ant.
## It was too good to be true. Why install 3 x doz cell sites on the roof tops
down town, of any mayjor city in NA...when you could do it all
with one-two cell site's.. with the super duper fractal ant.. which had loads
of gain, and dozens of narrow lobes, all neatly butted up against
each other. All the techs said this is pure BS, and will never happen.
## Several years later, I read some detailed scientific/peer reviewed expose
on the fractal and similar ant claims..and the poor
fractal ant myth was debunked once and for all. I'll be dipped if I can
remember where I read the expose article. [ it was not in
any ham publication either, it was a commercial /trade rag].
## here it is 2010... and no fractal ant's being used by any major cell co in
NA..at least that I'm aware of.
This kinda reminds me of the..."air car". 'They' have been working on this
damned air car for 15 years now... and always on the
verge of a break through. They even have a U tube video of it whizzing down
some European road at 60 mph. Apparently
'contracts' were signed with GM and Ford...and India was starting to..."
build them" etc. There was always some 'tech difficulty'
to be sorted out etc. The tech girls where I worked, were adamant the air
car was the real answer to mankinds car problems. The air
car 'engine' they depicted.. consisted of piston's and cylinders, and a
crankshaft, auto transmission etc..all being driven by a tank
of compressed air ! Perusing 'tree hugger.com' one day, several university
engineering students also got sucked into the bs.
They were all under the delusion that the air tank in the car could be refilled
at your local gas station, or a small 120 vac 1 hp air
compressor, like you have in the shop, would also RE-fill the onboard air tank.
Finally one pundit did the simple grade 9 maths. Energy = volume x pressure.
He calcuklated, that to make a small compact car
travel 180 miles on a single tank of air would require a 600 gallon tank
with a minimum of 10,000 PSI ! Now a 600 gal tank
is a big mother, and would have to be towed behind the sub compact car. To
handle 10, 0000 PSI would mean the wall thickness
of the tank would be absurdly thick. If you think a thick walled 600 Gal tank
is heavy, it's gonna be a helluva lot heavier with 10,000
psi. [The only compressed air engine I'm aware of is a torpedo]
## I looked at the bs on the aircar.com site. Guess what? NO street
address, NO ph number. NO fax number. NO info on which country 'they'
are in. NO e-mail address. The ONLY contact info was for "investor
relations info" [IE: send us $$$ and get in on the grnd breaking
technology].
The aircar is on a par with fractal ants.. both are a scam, and don't exist,
regardless of patents.
Later..Jim VE7RF
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