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Researchers Create 'Spray-On' 2D Antennas (phys.org)

Posted by BeauHD on from the cease-and-desist dept.

In a study published in Science Advances, researchers in Drexel's College of Engineering describe a method for spraying invisibly thin antennas, made from a type of two-dimensional, metallic material called MXene, that perform as well as those being used in mobile devices, wireless routers and portable transducers. Phys.Org reports: The researchers, from the College's Department of Materials Science and Engineering, report that the MXene titanium carbide can be dissolved in water to create an ink or paint. The exceptional conductivity of the material enables it to transmit and direct radio waves, even when it's applied in a very thin coating. Preserving transmission quality in a form this thin is significant because it would allow antennas to easily be embedded -- literally, sprayed on -- in a wide variety of objects and surfaces without adding additional weight or circuitry or requiring a certain level of rigidity.

Initial testing of the sprayed antennas suggest that they can perform with the same range of quality as current antennas, which are made from familiar metals, like gold, silver, copper and aluminum, but are much thicker than MXene antennas. Making antennas smaller and lighter has long been a goal of materials scientists and electrical engineers, so this discovery is a sizable step forward both in terms of reducing their footprint as well as broadening their application.

20 of 42 comments (clear)

  1. You scratched it! by Anonymous Coward · · Score: 2, Funny

    You scratched my antenna! How am I supposed to look at cat photos now?

    1. Re:You scratched it! by PopeRatzzo · · Score: 2
      Worse yet, a "2D antenna" is going to have "2 problems" which make it impractical:

      • 1. The material is not a perfect conductor. As such, putting, oh, I don't know, a nanowatt (just making up numbers) will melt the antenna.
        2. The material is not a perfect conductor. Lossy materials cause lower gain on the receive end.

      Food for thought. Yes, I read the article.

    2. Re:You scratched it! by LazarusQLong · · Score: 1

      one could spray it on in heavier concentrations, cover it with a protective coating, etc...being able to spray an antenna on, vice build an antenna then mount it is a big deal. Protective coatings are not unknown.

      --
      "Governments have been dominated by the corporate entities and citizens have ceased to matter in public policy" true in
  2. Thinner, but not smaller by Ozoner · · Score: 2

    This might make thinner antennas, but they won't be any smaller.

    They will still need a plastic support structure, will still need to be the same physical wavelength, and will still need to be mounted away from other metal.

    Sadly, it won't change the laws of physics.

    1. Re:Thinner, but not smaller by SeaFox · · Score: 2

      They will still need a plastic support structure, will still need to be the same physical wavelength, and will still need to be mounted away from other metal.

      Imagine painting an antenna onto the support structure for the roof of a building, and then overlaying non-metallic roofing material on top of it, or painting over it on the inside.

    2. Re:Thinner, but not smaller by beheaderaswp · · Score: 4, Interesting

      This might make thinner antennas, but they won't be any smaller.

      They will still need a plastic support structure, will still need to be the same physical wavelength, and will still need to be mounted away from other metal.

      Sadly, it won't change the laws of physics.

      You got that right.... Though electrical length can be fudged using Mandelbrot forms. Though it's still not the most efficient antenna.

      Most antennas in cell phones are considered "efficient dummy loads". Ever since they went internal there are all kinds of polarization/gain issues. At least with the old semi-vertically polarized antennas you didn't drop 20db of gain by turning your head.

      And you are right... spray paint an antenna onto a piece of metal... and the metal will couple distorting the radiation pattern.

      The whole technology is rife with pitfalls. But some MBA will try and make it work leading to more crappy products...

      --
      Another consultant who stuck it out.

      "We are the Priests, of the Temples of Syrinx..."
    3. Re:Thinner, but not smaller by religionofpeas · · Score: 1

      If you're going to put an antenna on a roof, there's nothing wrong with a conventional one.

      I'm guessing this technique is most useful for portable devices, where every penny counts. Spray the antenna on the inside of the plastic case.

    4. Re:Thinner, but not smaller by Ozoner · · Score: 1

      This only requires that you run a relatively thin wire.

      And if you are going to paint over it, it doesn't even need to be thin.

      FWIW, Hams have been using "invisible" stealth antennas since day one.

      And invisible antennas have been printed on car windscreens for years

    5. Re:Thinner, but not smaller by LazarusQLong · · Score: 1

      I see you have not heard of fractal antennas also known as a variation on space filling antennas. https://en.wikipedia.org/wiki/...

      --
      "Governments have been dominated by the corporate entities and citizens have ceased to matter in public policy" true in
    6. Re:Thinner, but not smaller by LazarusQLong · · Score: 1

      how about we stop being simplistic in our thinking? Imagine I have a metalic substrate, I spray a 4 mm coating of urethane to it, then I my antenna over that after the urethane has dried. Now I have an antenna with a backplane 'distorting'; the beam in one direction, or one could say, attenuating the incoming signals from one direction. Would this have value? Depends on my use case. Imagine instead I use an expanding foam as my barrier rather than simple urethane? Now I can develope a larger thickness if I so desire. In both cases I mention above one can create much cheaper antennas in a conformal mode.

      --
      "Governments have been dominated by the corporate entities and citizens have ceased to matter in public policy" true in
    7. Re:Thinner, but not smaller by beheaderaswp · · Score: 1

      In both cases I mention above one can create much cheaper antennas in a conformal mode.

      And they won't work....

      You can't slap a metal "backplane" on a sprayed on 2d antenna and get anything other than a ridiculous standing wave ratio. Also, the electronics used in a conformal antennas to create directional beamforming are prohibitively expensive and even classified. "Backplanes" do not create directionality.

      The next time you Wikipedia dive for a comment- make sure you read the whole article.

      --
      Another consultant who stuck it out.

      "We are the Priests, of the Temples of Syrinx..."
  3. Ringworld Throne by DougDot · · Score: 4, Interesting

    This spray-on antenna technology first appeared in Larry Niven's Ringworld Throne, published in 1996.

    1. Re:Ringworld Throne by Rick+Schumann · · Score: 1

      Intimately familiar with Larry Niven's works. I think you're thinking of Puppeteer technology, that allowed entire audio-visual surveillance and communications devices to be literally sprayed onto surfaces; it was described as looking quite a bit like a spiderweb.

  4. A link that works by Procrasti · · Score: 2

    http://theconversation.com/spray-on-antennas-unlock-communication-of-the-future-103637

  5. How to do you connect to it? by viperidaenz · · Score: 1

    You need to spray it on something, then connect a wire to it. Why not use the wire for the antenna?
    Like a PCB antenna, which is only 35um thick copper.

    If you want something thin and transparent, why not use ITO? It has similar resistivity to titanium carbide.
    Alternatively if this is cheaper than ITO, why not use it for LCD manufacturing?

    1. Re: How to do you connect to it? by Ozoner · · Score: 1

      > and in the middle of it you have a giant mammoth antenna

      But this doesn't make it smaller or more compact.

      It still needs the same wavelength and the same spacing from nearby components.

  6. The link seems to have gone bad by I+kan+Spl · · Score: 1

    The second link in the summary "describe a method for spraying invisibly thin antennas" seems to go to an article titled "Facebook stops sending staff to help political campaigns". Was this link changed when being posted?

    --
    My UID is prime and so is this number: 09 F9 11 02 9D 74 E3 5B D8 41 56 C5 63 56 88 C0.
  7. WOW! Conductive paint! by Anonymous Coward · · Score: 1

    We don't have that where I come from.

  8. Very limited capability by mysidia · · Score: 1

    sprayed on? I imagine this cannot transmit or receive very much RF power.... A few milliwatts, perhaps. Not going to be able to receive a weak VHF/UHF signal or transmit at 5 or 10 Watts, comparable to a portable radio.

  9. Not exactly a new idea by Rick+Schumann · · Score: 1

    I don't think this is a new or ground-breaking development, considering that we've had the ability to draw conductors with a pen for quite some time now. Not particularly cheap, and tricky to solder to or otherwise connect to, but you could draw quite a few antennas with it. I'd bet good money I could, for instance, draw an HDTV antenna on a piece of cardboard with this, and it'd have decent gain. The 300-to-75-ohm balun would be a challenge, though, probably have to just buy one of those. Now, imagine a special print cartridge for an inkjet printer, or special toner for a laser printer, or a plotter pen. Just design the antenna you want in CAD then print it straight onto whatever.