Steve Best VE9SRB published an article in QEX a number of years ago
showing that fractal antennas were no better than conventionally
"meander line" antennas. My recollection when they first were being
showcased in the trade magazines were articles that showed gain and VSWR
curves with multiband coverage, but there were never any comparisons to
show that these fractal designs were better than conventional
non-fractal techniques. IOW, yes, you can make an electrically small
broadband antenna using fractal geometry, but it isn't necessarily any
better than a conventional meander line antenna of the same size. Just
because fractals occur over and over in nature doesn't prove they make
better antennas. Proving they make better antennas requires valid NEC
simulations and/or measurement data.
73, Mike W4EF.........................
On 2/20/2010 10:02 AM, Neal Campbell wrote:
> The greatest story on this is from a show on PBS about Fractal Geometry.The
> first half of the show is about how skeptical and belittling the mathmatical
> world was about fractal geometry when it could be proven over and over and
> seen recurring everywhere in nature.
> The second half of the show was about the practical applications of fractals
> and they spent quite a bit of time telling the story of Nathan Cohen who as
> a ham started to wonder if antennas would benefit from fractal design and
> wrote a paper in Communications Quarterly. He kept going, finally starting
> up the Fractal Antenna company which sells antennas it seems in the cell
> phone market, etc.
> Its a great great show.
> Neal Campbell
> Abroham Neal Software
> (540) 645 5394 NEW PHONE NUMBER
> Amateur Radio: K3NC
> Blog: http://www.abrohamnealsoftware.com/blog/
> DXBase bug reports: email to firstname.lastname@example.org
> Abroham Neal forums: http:/www.abrohamnealsoftware.com/community/
> On Sat, Feb 20, 2010 at 12:40 PM, Vic Watkins<email@example.com>wrote:
>> The web site was up and working yesterday. http://www.fractenna.com
>> Vic (W7VLW)
>> On 2/20/2010 6:15 AM, TexasRF@aol.com wrote:
>>> You will find information about Fractal Antennas in back issues of Ham
>>> Radio Magazine. CQ Magazine offers CD ROM copies I believe.
>>> Gerald K5GW
>>> s In a message dated 2/20/2010 5:03:32 A.M. Central Standard Time,
>>> Jim.firstname.lastname@example.org writes:
>>> Some time back there was an article in QST about Fractal Antennas and I
>>> believe they used one on 10 meters.
>>> So far, searches find listings, but the pages have been blank.
>>> They'd be a limited space antenna with negative gain and are more often
>>> associated with cell phones
>>> Anything happening along this front and where did all the examples go?
>>> Roger (K8RI)
>>> ## Fractal ant's were the subject of a big article in Scientific
>>> American many year's ago. Cell co's were all going to use em, greatest
>>> sincesliced bread, 1.2 deg BW, etc. Fractal ants are a myth, just like
>>> 'air car'. Jim VE7RF
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