Alien Antenna?
 

Hey guys,

I need some help. I had a long meeting with the inventor of this antenna which he claims can send/receive full duplex commo on several frequency ranges at the same time. Yup. I know it sounds like alien technology, and I have some test data from a chamber at NASA but it just seems too good to be true.

He insists this antenna passively tunes to any radio you plug it into, and it
can handle as much power as you want to pump through it (only limited by the
size of the transmission cable). The antenna can tune to freqs which go from 2Mhz to 5.8 Ghz with the same antenna.

It will supposedly freq hops - no problem - and based on the data I saw it averages a minimum 6dbi - true gain.

Needless to say, I don’t believe him but can’t prove him wrong. Is there anyone that has access to a chamber in SOF so I can get feedback from operators and not rock scientist! My expectations are low, but if this antenna can do ½ of what he claims it does it will revolutionize LOS comms. One antenna for all my radios, with a better dB gain than the antennas we commonly use AND its the size of a
Paperback book. No more antennas getting caught on brush, tree limbs, door frames, rotor blades, etc. One more thing, I guess because the way that its constructed it can take substantial damage and still transmit ‘cause its a fractional antenna.

Anyway, can someone help me out in vetting these claims .

Thanks all-
DeMo

Is there any literature on the web about this antenna?

I found this digging around.

DeMo, was the term Hexagonal and Pentagonal Fractal Multiband Antennas used?

Off the top I am thinking that in spite of the capabilites of the antenna you would still need to have a radio that was capable of discriminating between all the signals that are out there in that wide of a band. I have sat through some briefs on emerging MIMO technology, but the systems were operating on distinct bands that provided sufficient frequency separation in order to limit interference. The number of antennas was reduced, but there were still multiple systems being operated.

The short article has some diagrams associated (follow the link at the bottom)but no reference to scale. There is a Tech paper that I just pulled up...it required registering on the NASA Tech Briefs site.

Hexagonal and Pentagonal Fractal Multiband Antennas
John F. Kennedy Space Center, Florida
Friday, July 01 2005

These antennas could be suitable for multifunctional wireless-communication products.


Multiband dipole antennas based on hexagonal and pentagonal fractals have been analyzed by computational simulations and functionally demonstrated in experiments on prototypes. These antennas are capable of multiband or wideband operation because they are subdivided into progressively smaller substructures that resonate at progressively higher frequencies by virtue of their smaller dimensions.

The novelty of the present antennas lies in their specific hexagonal and pentagonal fractal configurations and the resonant frequencies associated with them. These antennas are potentially applicable to a variety of multiband and wide-band commercial wireless-communication products operating at different frequencies, including personal digital assistants, cellular telephones, pagers, satellite radios, Global Positioning System receivers, and products that combine two or more of the aforementioned functions. Perhaps the best-known prior multiband antenna based on fractal geometry is the Sierpinski triangle antenna (also known as the Sierpinski gasket), shown in the top part of the figure. In this antenna, the scale length at each iteration of the fractal is half the scale length of the preceding iteration, yielding successive resonant frequencies related by a ratio of about 2. The middle and bottom parts of the figure depict the first three iterations of the hexagonal and pentagonal fractals along with typical dipole-antenna configuration based on the second iteration. Successive resonant frequencies of the hexagonal fractal antenna have been found to be related by a ratio of about 3, and those of the pentagonal fractal antenna by a ratio of about 2.59.

This work was done by Philip W. Tang of Kennedy Space Center and Parveen Wahid of the University of Central Florida. For further information, access the Technical Support Package (TSP) free on-line at www.techbriefs.com/tsp under the Electronics/ Computers category. KSC-12393/482


http://www.techbriefs.com/component/.../122?task=view

Multiplexer
 

If you were to plug more than one radio into a single antenna, wouldn't you would still need a multiplexer?

I would see a multiplexer significant if all signals were being processed and distributed to a single end point. I believe what is being proposed is the transmission of distinct signals to disparate systems and locations.
The signal path is not the same and it isn't a composite signal.



Not sure if I am expressing myself clearly.....

Do you have the white paper on this antenna with a picture of it?

Can't speak for what would have to be done equipment-wise in order to handle multiple sets transmitting on different frequencies simultaneously without burning out any other radio plugged into the same antenna, but any antenna should be able to transmit multiple frequencies simultaneously. The antenna will transmit the two signals combined. It's just a matter of how resonant each freq. is for the given antenna. All the receiving radio is going to do is deconvolve the signal using a fourier transform...which they already do....in order to isolate the frequency they are looking for. As far as a listening radio is concerned, it doesn't matter where the *extra* frequencies that are being transmitted come from...might as well be the FM station down the street because the radio is still going to filter them out.

I don't see how you could receive on the same antenna that is actively transmitting without burning out your receiver though.

10lb brains - lol
 

Hey guys,
Thanks for all the knowledge sharing on this antenna. I may have overstated it's capability by mixing terms.

The inventor claims that the antenna doesn't need to be "cut" per se because it passively tunes to whatever you plug it into. It sounded like the antenna "dumbs down" to whatever the capability of the radio is. So if the system can do full duplex, than so can the antenna, if the radio can frequency hop - the same antenna will freq hop. If the system pushes out 400 watts or 4 watts the antenna can handle both efficiently. It can also have multiple radio's from multiple frequency bands all plugged into it at the same time. I don't think we can transmit on it all at the same time, but I've got no way to test that.
I do know, by looking at that NASA data, that the radio has an extremely "deep bucket", so it's super sensitive and can pick up very weak signals. As a matter of fact they recently tested it in underground facilities and found it to be significantly more effective than the systems they currently had in place.

This is fresh off the brainpan and into the field testing market so there isn't any real data to crunch. I've got some graphs from NASA testing that says it phenomenal, but like I said for all I know it was some other antenna and not the one I've got in my hands. However, if I could get someone I trust to tell me this thing is special, or not - and he is one of our own - then I would be energized.

I read what Ret10Echo wrote, although it took a couple of times and I couldn't read it without moving my lips to sound out the big words - but many of the things you mentioned about fractional antenna's the inventor also mentioned. This antenna looks like some kind of circuit board that has a bunch of little hexagonal shaped things all over it (if you could see what it looked like disassembled).
I don't know if that adds to the discussion or not.

There is no REAL documentation on this antenna you can find on the web. What you may find is all a bunch of hearsay and theoretical thinking. I'm not holding onto the information 'cause I'm competing with some other vendor or anything like that. We are the sole distributor of this item to DOD, but right now we don't know if we want to put our name on it until we know for sure it can do what it says it can do.

I'm hoping to tap into some REAL data that we can measure this antenna against. Would anyone be willing to look at this thing from an independent view and see if it's for real? I'm gonna talk to some of my old 1st Group Commo buds after the holidays to do some field testing, but I need someone that can just measure dB gain and the pattern it resonates at. You know, all that stuff they taught me at the 18E course 15 years ago on antenna thereoy!
Do you guys know of anyone who would be interested in doing that?

Thanks again, and Happy Thanksgiving all -

DeMo

I am willing to help this guy out.

If it works as advertised, I will let everyone know and will even hand out his business cards. But if not, I will also let everyone know.

Aplogies for geeking out this morning. You caught me fresh. :D

I did manage to download a Tech Brief on the antenna design (NASA Tech Briefs KSC-12393/482). Not a huge amount of information but the design layout is what you mention and it gets into the theory around it so we are talking about the same thing.

In a simple terms it is a grouping of little dipoles bundled in hexagons or pentagons and arranged around a center opening (see image below) and center fed (thus the dipole). The whole thing is basically a wafer from what I saw.

If it is a DoD project there are organizations that can play with those types of things and can do some controlled field work and provide an assessment. Project-managment types should be able to plug in to them. (Look up JITC or AFOTEC they may be able to point them in the right direction)

I'll let you know what happens
 

Hey guys,
I'm gonna try to get some of the guys from 1st SFG to field test this thing and I'll post what it does here. I'll also see if I can get one of the 1st Group guys to put in thier observations. Next week is kind of nutz at 1st group 'cause it Menton Week (for some reason we celebrate the deactivation of our unit?!). Anyway, I can't make any promises but I will let you know what happens one way or another.

Gregg, I hope to make my way to Bragg sometime in FEB after the commo convention in San Diego, CA and will definately look you up when I get there - if you're interested in playing with this thing.

Ret10Echo; please continue to bring your technical expertise. I need to understand all aspects of this technology and guys like you and Greg will keep me honest. I'm hoping this is a product that sells itself, and I can let the stats stand alone. The field test will let me know just what this antenna is capable of doing.

Again guys, thanks for your comments and I'll keep you posted.
DeMo

would like to help
 

I work in the force mod shop over at and I think after the holidays I may be able to get this into a test down in Tampa, it would take a few calls but I think it could work out, if this does do half of what it say's it will do then it would be something that every commo guy should have even if he is not tx on multiple freq's at the same time at least he won't have to change out ant. If you would like to push this to testing just drop me a line and I will give you my contact info

Test Chamber
 

I would definately be interested in getting this antenna chambered.
I did my first field testing of it using an Motorola XTS 5000 (http://www.motorola.com/business/US-...008406b00aRCRD) radio and the bottom line results were that LOS comms using the standard antenna I could reach out .9 miles consistantly with 5X comms. When I switched out the antenna to the Alien Antenna I was able to reach out to 1.6 miles. So that was in increase of .7 miles!!!
Not too shabby at all for just swapping out an antenna, eh?
Send me an email or feel free to call me at 877-772-8383 and we'll talk about making arrangements if you can do it, okay?
Thanks so much for your help!
:)

Hey DeMo, VHF or UHF?

Shoot me a PM if you develop any opinions on building penetration as you play around with it.

R10

Yep keep us in the loop about this antenna. I know a little about antennas, but like you its good to really test the hell out of it to see what it really can do. Paper can lie.
:munchin
AL