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Old Marconi Patent Inspires Tiny New Gigahertz Antenna

Posted by samzenpus on from the getting-small dept.

agent elevator writes Gehan Amaratunga and a group of engineers in England noted that the Guglielmo Marconi's famous British patent application from 1900 had an interesting and little noticed detail. It depicted a transmitter linked to an antenna connected to a coil, which had one end dangling while the RF signal was fed to the middle of the coil. That detail inspired them to develop a way to reduce the size of a GHz antenna without significant transmission loss by using dielectrics as the radio wave emitting material instead of conductors.

12 of 76 comments (clear)

  1. My B.S. Detector is Going Off by Bruce+Perens · · Score: 5, Informative

    Marconi's connection to the center tap of a coil with one end not connected worked by broken symmetry? Really? It wasn't just a method of tuning a coil to the correct reactance for a particular frequency?

    --
    Bruce Perens.
    1. Re:My B.S. Detector is Going Off by JonWan · · Score: 2

      Clearly none of the "Engineers" had a ham license.

    2. Re:My B.S. Detector is Going Off by elgatozorbas · · Score: 2

      I was also a bit surprised by that part. It rather looks like a wave is launched into a piece of dielectric, which then may act like a dielectric waveguide. Somewhat. More or less...
      In any case I can hardly believe that quantum theory is needed to explain the behaviour of antennas. Most surprising, however is to find such clumsy explanation in Spectrum, the flagship journal of the IEEE.

    3. Re:My B.S. Detector is Going Off by Bruce+Perens · · Score: 2

      If the end of the coil that is hanging is grounded (earthed), it becomes an autotransformer. As it's shown, it's a variable inductor and the disconnected end is irrelevant and has no meaningful physical effect at the frequency a spark transmitter could have reached.

      This comment seems to get closer to what they actually mean in their scientific paper. But the article about it is garble and the paper might suffer from second-language issues, and a lack of familiarity with the terms used in RF engineering.

      --
      Bruce Perens.
  2. 100 year old news? by gurps_npc · · Score: 2
    So basically, this is a 100 year old invention, that some people just happened to notice today?

    Hey, people I don't know know if you are aware, but if you take a radar unit, drop the receiver and turn up the power, you can cook FOOD on it to!

    --
    excitingthingstodo.blogspot.com
    1. Re:100 year old news? by cdrudge · · Score: 2

      Hey, people I don't know know if you are aware, but if you take a radar unit, drop the receiver and turn up the power, you can cook FOOD on it to!

      Really? That's really cool. I guess it's a RadaRange then?

    2. Re:100 year old news? by Jesus_666 · · Score: 2

      Excuse me but that sounds entirely implausible. Cooking food with a radar unit? I'll believe it when someone uses one to, say, melt a chocolate bar. Until then keep your loony theories to yourself!

      --
      USE HOT GRITS WITH STATUE OF NATALIE PORTMAN (NAKED AND PETRIFIED)
  3. Obviously by Anonymous Coward · · Score: 5, Funny

    This means that Guglielmo Marconi's hard work was stolen without compensation and he has no incentive to invent anymore. Extends patents to 115 years!

  4. have to admit... by hitmark · · Score: 3, Interesting

    I read the title as "old macaroni patent" on first glance.

    --
    comment first, facts later. http://chem.tufts.edu/AnswersInScience/RelativityofWrong.htm
    1. Re:have to admit... by rubycodez · · Score: 2, Funny

      And it's so ambiguous. Is that a patent on old pasta? a macaroni patent that expired? A patent inscribed on a tube of pasta? patent on fancy 18th century duds?

    2. Re:have to admit... by sconeu · · Score: 2

      Clearly, the patent is for sticking a feather in one's hat.

      --
      General Relativity: Space-time tells matter where to go; Matter tells space-time what shape to be.
  5. Maxwell's equations fail? by wbean · · Score: 2

    Tech reporters should be licensed. I seriously doubt that Maxwell's equations are failing: "Maxwell’s equations explain how high-frequency flows of electrons in conductors generate electromagnetic waves, but they do not explain how an insulating material, where there is no flow of electrons, would also act as an antenna."