Metamaterial Antenna Technology Surpasses Yagis, Receives Patent

Amateur Radio inspired innovation is always interesting news.

73, John, WØPV



Fractal Antenna Systems, Inc. (FRACTAL) today announced upcoming issuance of a fundamental patent on unidirectional antennas, that replace existing applications with smaller, more versatile and visually pleasing options and form factors. The breakthrough is made possible by the firm’s proprietary fractal and metamaterial technology.

For more than two decades, FRACTAL has explored, developed, and invented fractal-based electromagnetic technology, using size-shrunk fractal resonators/fractal antennas with a broad and or multiband advantage. Fractals have self-similar structure on a variety of size scales. Close-packing of the fractals makes this a metamaterial, producing a unique composite: a ‘fractal metamaterial,’ that enables wave bending, gain, and control in ways previously not attained. For example, fractal metamaterials made possible the firm’s invention of the invisibility cloak, for which it now holds the patent portfolio for virtually all aspects and uses.

The new fractal metamaterial technology offers a superior alternative to Yagi-Uda antennas. Resembling a fishbone, ‘Yagis’ are among the most used of antenna designs because they produce high gain directional coverage with only one electrical connection point. But Yagis suffer from long, stretched form factors that make them susceptible to wind load, environment, and a lack of aesthetic appeal.

FRACTAL inventors found that fractal metamaterials, with their ability for wideband evanescence and surface waves, could produce parasitic antennas that were highly directional and far smaller in form factor than Yagis. From VHF to frequencies encompassing Wi-Fi and even 5G, the new “metablade”™ antennas can be drop replacements for their Yagi counterparts, while their smaller size lets them be used in situations where Yagis cannot.

A key difference for the metablade™ antennas is they are not locked into a fishbone arrangement. Notes co-inventor Nathan Cohen (W1YW): “the gain doesn’t need the elongated sideways arrangement of the Yagi. Metablade™ antennas can be a smaller, vertically-oriented structure with the same or better performance than the Yagi. A metablade™ antenna looks more like the mounting bracket for an antenna rather than the antenna itself. It’s a huge difference. This becomes a superior antenna choice for tower and building owners. Fishbones are best left for the cat.”

FRACTAL recently announced its first metablade™ antenna product—a wideband antenna for public safety needs, at the In-Building Wireless Congress. Additional rollout of SCADA, Wi-Fi, 5G, and other applications commence in the fall. The metablade™ antennas are exclusively offered and sold through FRACTAL.

ABOUT FRACTAL ANTENNA SYSTEMS, INC.

Fractal Antenna Systems, Inc. (www.fractenna.com) supplies products and solutions for the world's most demanding wireless, electromagnetic, and electronic applications. Backed by over six dozen U.S., and international patents, plus patents pending, FRACTAL is the recognized pioneer in fractal and electromagnetic technology, with extensive research and field experience over 25 years in business. The company is a privately held and headquartered in Bedford, Massachusetts, USA.

View source version on businesswire.com: https://www.businesswire.com/news/home/20190612005672/en/

 

Thanks for posting John.

The first example of what I did on this was the ham band at 900 MHz. That was, oh, 9-10 years ago. Like many of my new ideas/inventions, they sit around until I think there is a demonstrable need. I sit on many even now.

Shortly after the PR came out, I received two emails basically saying that 'nothing beats Yagis and you're full of BS', and the additional puzzle of to the effect that I was advocating injuring cats(from pointy fish bones). See John's italics....

The first point: Yagis are fine for most ham usage, especially at HF and low VHF. At higher frequencies--and that is where MOST Yagis ARE used-- they are not the best (parasitic antenna) option from a size, arrangement, and form factor standpoint. The PR describes, briefly, this new and better solution.

Uda did millions of people a huge service with the invention of the 'Yagi', but we should be surprised it lasted this long--over 90 years.

To put it simply, Yagis 'undersample' the near field in their parasitic arrangement, in part because of the mutual coupling caused by the large dipole-like elements. There are clever way(s) around this (in a parasitic arrangement), which lead to smaller size and form factor for the same gain, hence the new invention. BTW, the new invention is not a Yagi. Yagis are a class of parasitic directional antennas. Not all parasitic such antennas are 'Yagis'.

Next, in cases where Yagis shine--such as HF--recent work shows a great benefit beyond the 'NBS Yagi' days. In particular, I cite (Professor) Jim Breakall's(WA3FET) tremendous work on 'OWA' designs. Cool stuff!

Finally, onto cats-- No, don't harm cats. It was a joke. Put simply, be sure any food you serve to your pet is safe for their consumption.

73
Chip W1YW

 

That only works if you really don't like your cat!!

Looks like the really cool aspect of this is that it could built right into a wall or a side of a building!

Are they easily scalable to lower frequencies? (like lower VHF or upper HF?)

 

The fractal metamaterials are on a conformable circuit board. For cost reasons, it presently doesn't make a lot of sense to make these (commercially) under about 300 Megs (top of VHF).

I've been building circuit board based HF antennas for my station for quite a while---and its just too expensive for HF (for others). IOW I think the options we (hams) use at HF are pretty good from a performance AND cost issue.

Then again, I still see a lot of resistance(pun) to even bending wire. Catch the Hamnation podcast with Valerie last year (NV9L) where I give a simple example.

73
Chip W1YW

 

Chip ,
How about a link ?
Also a time on video ?
It would help , with over an hour video , I do not know , but like many references to something on these videos - that something only last 5 min.
Having to search through one or more videos , each lasting an hour or more .
I would rather give my time to info that is not so hard / time consuming - time is the only thing we really have to spend !

 

Here is the slide deck from the Tech Symposium talk on the new tech, from Radio Club of America--Nov 2017. A live (gain) demo was also done--with a VNA . Live demos really resolve skeptical concerns!

https://www.radioclubofamerica.org/wp-content/uploads/2017/11/8-RCATechSymp2017COHEN.pdf


Here is the Hamnation video....a bit dark and slightly off in picture order...see 'fracvert'.

 

"No cats were harmed during the making or use of these antennas!"

 

Chip ,
Ya that is the one I found with a search , then I can back with my post , seeing that it was over an hour .
Where to start , this is an old story about new ideas , at least to me .
I'm one of those types that when I get something , new or used , I open it up to get some ideas of what I have , much like Dave's EEV blog https://www.google.com/search?q=dav...2.69i57j0l5.8680j0j7&sourceid=chrome&ie=UTF-8
One of his quotes " don't turn it on / tear it apart "
So looking to get a better grasp on why the lower bands don't play well with this idea .
I did watch the Nova [ if I remember correctly ] PBS program .
And caught a bunch of the threads here over the last few yrs.
I think it was the 1st time a caught that you ideas did not work / cost for lower bands .
It can take me longer to get my head rapped around something new to me , most because I'm a self taught type , at least that's the excuse I use .

 

Couldn't resist highlighting the fishbones metaphor. Rest assured that my feline companion Rudi W4SUN and I understood and appreciated the gag. (pun intended)


73, John, WØPV

 

Dang cat's these days , laying down on the job

 

Fractal metamaterials (I assume you are referring to)are close spaced resonators, roughly 1/10 to 1/8 wave in size apiece. On 20 m, each would be roughly 2+ meters across. Now make lots of them, spread them on a dielectric manifold, and put them up in the air. It will be a smaller form factor on 20M than your Yagi, but will look more like a crazy quilt in the air--and expensive.

Doing this on, say, 700MHz makes more sense.

73
Chip W1YW

 

What makes it expensive ?
I'm guessing the size of the circuit boards , I haven't seen any that big .
Except for the one in the Hamnation video , looked like traces on a rolled up material ?
Also on the example of small circuit boards making up the traps on the drawing of the dipole , I was thinking they were coils for shorting the total length of the dipole , until you mentioned capacitors inside - so traps .
My guess is that some type of calculator / program that figures dimensions / shapes of the traces - are you secret sauce ?

 

Thank you Dave.

Yeh, its been a tough ride but I can finally say I am at the point where I can enjoy it--and a big piece of that is enjoying others.

I worry about ham radio--not about hams, but about our perception 'out there' and the sense we are age-enfeebled; antiquated; living in the past; you name it.

That is wrong, wrong, wrong.

We are an enabling service/hobby (see, I said it!) that has a 100 year philosophy of come as you are and become what you want to be. Ain't that America, as they say . And clearly hams across the globe share our approach. That is a very unique and important thing.

Furthermore, if you sense we are GROWING, you are correct.

73
Chip W1YW

 

Here's one of the MAX sections...this is not the fractal metamaterial stuff in the press release but part of one of my HF antennas; the caps are on the inside nestled against the foam.

PCB is not cheap. Should be but isn't. I refuse to buy substrate from PRC.

Not traps. Traps are low pass filters. These are electrically long---physically short-- radiating sections. They look like traps, for sure.

Simulation has limitations as a predictive source with complex geometric structures. Easier to build and play with it. The math( for impedance/gain)? Good luck! As soon as you do a series expansion you discover that there are no (mere) 'leading terms' and you have to pay attention to the whole (dang) expansion.

73
Chip W1YW