Bombshell: The Hedy Lamarr Story Videos for Engineers
By now, most people involved with spread spectrum
communications are (or should be) aware that Hollywood starlet
is credited for being the first to suggest a frequency hopping scheme for secure communications.
If you do a Google search on Hedy Lamarr and spread spectrum, you see that except for
a few mentions on tech websites, it has only been in the news since the end of the last
decade. Scientific American magazine ran an article titled, "Hedy Lamarr: Not Just a Pretty Face," in 2008. Google honored her
on November 9 (her birthdate), 2015, with a
Doodle on their
"The most beautiful woman in the world," with the assistance of her co-inventor-composer
George Antheil, came up with the idea while working on a piano piece. Ms. Lamarr and
Mr. Antheil were concerned about the massive torpedo attacks by German
U-boats against not only naval ships but passenger and merchant ships
in the northern Atlantic ocean. The objective was to discourage supply shipments to Europe,
which was already under siege by the Third Reich. Radio-controlled torpedoes were used
by Allied forces against Axis warships and submarines, but the signals were easily jammed
by high power transmitters broadcasting on the same frequency as the controller. Frequency
hopping would allow the controller to change frequency faster than the enemy could keep
up with to block. Both the transmitter and the receiver are given an identical schedule
of frequencies and times for synchronization (using a
type of tape for programming). Just as your ears and brain can pick out known notes to
a melody while ignoring other non-related notes playing simultaneously, the spread spectrum
receiver heeds only information on its frequencies and ignores all others.
Lamarr and Antheil share the patent titled "Secret Communication System" (US2292387) which
was granted on August 11, 1942; however, the military did not adopt the scheme for tactical
use until nearly two decades later. Interestingly, the patent application was filed on
June 10, 1941 - six months prior to the Japanese bombing of Pearl Harbor that marked
America's official entrance into World War II. Note also that the inventors are
listed as George Antheil and Hedy Kiesler Markey. Hedy Lamarr was her screen name, Markey
was her married name, and her birth name was Hedwig Eva Maria Kiesler.
"Bombshell: The Hedy Lamarr Story," produced by Zeitgeist Films, is
just now showing in select theaters around the country, so it will be a few months before
it is available online or on DVD. I realize that the double entendre created by using
the the term "https://www.merriam-webster.com/dictionary/bombshell" refers to both explosive
torpedoes and the common vernacular for a very attractive woman. However, it is notable
that a film meant at least partly to quash the concept of recognizing women for their
beauty rather than for their brains would choose to make such a blatant comparison. Surrendering
of core principles is often done in the pursuit of profit (aka
Bombshell: The Hedy Lamarr Story
Secret Communication System - U.S. patent
"This invention relates broadly to secret communication systems involving the use
of carrier waves of different frequencies, and is especially useful in the remote control
of dirigible craft, such as torpedoes.
An object of the invention is to provide a method of secret communication which is
relatively simple and reliable in operation, but at the same time is difficult to discover
Briefly, our system as adapted for radio control of a remote craft, employs a pair
of synchronous records, one at the transmitting station and one at the receiving station,
which change the tuning of the transmitting and receiving apparatus from time to time,
so that without knowledge of the records an enemy would be unable to determine at what
frequency a controlling impulse would be sent. Furthermore, we contemplate employing
records of the type used for many years in player pianos, and which consist, of long
rolls of paper having perforations variously positioned in a. plurality of longitudinal
rows along the records. In a conventional player piano record there may be 88 rows of
perforations, and in our system such a record would permit the use of 88 different carrier
frequencies, from one to another of which both the transmitting and receiving station
would be changed at intervals. Furthermore, records of the type described can be made
of substantial length and may be driven slow or fast. This makes it possible for a. pair
of records, one at the transmitting station and one at the receiving station, to run
for a length of time ample for the remote control of a device such as a torpedo.
The two records may be synchronized by driving them with accurately calibrated constant
speed spring motors, such as are employed for driving clocks and chronometers. However,
it is also within the scope of our invention to periodically correct the position of
the record at the receiving station by transmitting synchronous impulses from the transmitting
station. The use of synchronizing impulses for correcting the phase relation of rotary
apparatus at a receiving station is well-known and highly developed in the fields of
automatic telegraphy and television."
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