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Thread: Hedy Lamarr & frequency hopping communications

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    Hedy Lamarr & frequency hopping communications

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    Was watching PBS "How we got to Now" last night. This one was about sound and not as good as other installments. But it had an interesting blurb about how a Hollywood starlet helped in WW2

    https://en.wikipedia.org/wiki/Hedy_Lamarr

    from the wiki page:

    During her first marriage, Lamarr developed a keen interest in applied science, and bored by her acting career, utilized this knowledge as an inventor. At the commencement of World War II, keen to aid the Allied war effort, she identified jamming of Allied radio communications by the Axis as a particular problem, and with composer George Antheil, developed spread spectrum and frequency hopping technology to defeat it.[4] Though the US Navy did not adopt the technology until the 1960s, the principles of her work are now incorporated into modern Wi-Fi, CDMA and Bluetooth technology,[5][6][7] and this work led to her being inducted into the National Inventors Hall of Fame in 2014.[4][8]

    Lamarr's reputation as an inventor is based on her co-creation of a frequency-hopping system with George Antheil, an avant garde composer and neighbor of Lamarr in California. During World War II, Lamarr was inspired to contribute to the war effort, and focused her efforts on countering torpedoes. In her home, explains author Richard Rhodes during an interview on CBS, she devoted a room to drafting her designs for frequency-hopping.[17]

    Lamarr and Antheil discussed the fact that radio-controlled torpedoes, while important in the naval war, could easily be jammed by broadcasting interference at the frequency of the control signal, causing the torpedo to go off course.[18] Lamarr had learned something about torpedoes during her marriage to Mandl. Lamarr and Antheil developed the idea of using frequency hopping to avoid jamming. This was achieved by using a piano roll to unpredictably change the signal sent between a control center and the torpedo at short bursts within a range of 88 frequencies in the radio-frequency spectrum (there are 88 black and white keys on a piano keyboard).

    The specific code for the sequence of frequencies would be held identically by the controlling ship and in the torpedo. It would be practically impossible for the enemy to scan and jam all 88 frequencies, as computation this complex would require too much power. The frequency-hopping sequence was controlled by a player-piano mechanism, which Antheil had earlier used to score his Ballet Mécanique

    On 11 August 1942, U.S. Patent 2,292,387 was granted to Hedy Kiesler Markey, Lamarr's married name at the time, and George Antheil. This early version of frequency hopping, although novel, soon was met with opposition from the U.S. Navy and was not adopted.[19] The idea was not implemented in the U.S. until 1962, when it was used by U.S. military ships during a blockade of Cuba after the patent had expired. Lamarr's work was honored in 1997, when the Electronic Frontier Foundation gave her a belated award for her contributions.[4] In 1998, an Ottawa wireless technology developer, Wi-LAN Inc., acquired a 49% claim to the patent from Lamarr for an undisclosed amount of stock.[20]

    Lamarr's and Antheil's frequency-hopping idea served as a basis for modern spread-spectrum communication technology, such as Bluetooth, COFDM (used in Wi-Fi network connections), and CDMA (used in some cordless and wireless telephones).[21] Blackwell, Martin, and Vernam's 1920 patent[22] seems to lay the communications groundwork for Lamarr and Antheil's patent, which employed the techniques in the autonomous control of torpedoes.

    http://www.dioramaconcept.com/blog/s...n-hedy-lamarr/
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    Senior Member macaroonie's Avatar
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    My eyesight is getting bad Tom , did that say Topless or Torpedo's on both

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    Typical woman...can't make up her mind which frequency to use
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    RIP 2021 SEAWOLF97's Avatar
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    Quote Originally Posted by toddalin View Post
    [/video]
    the location of that video is at a very distinctive place called "Vasquez Rocks".
    Many Westerns filmed there and also had a stucco fort that showed up in many films.

    https://en.wikipedia.org/wiki/Vasquez_Rocks

    Went there on a field trip with the Scouts , long..long ..long ago
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    Quote Originally Posted by SEAWOLF97 View Post
    the location of that video is at a very distinctive location called "Vasquez Rocks".
    Many Westerns filmed there and also had a stucco fort that showed up in many films.

    https://en.wikipedia.org/wiki/Vasquez_Rocks

    Went there on a field trip with the Scouts , long..long ago

    I've been there myself several times, but it's been years.

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    Senior Member grumpy's Avatar
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    Lol, I knew someone would have to bring up Hedley.
    Vasquez Rocks is fun to hike around... although I get a weird feeling that a fight with a lizard man is inevitable...

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    Senior Member Ducatista47's Avatar
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    A Gorn, if I remember correctly.
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    Senior Member grumpy's Avatar
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    Give the man a prize!

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