From
Strapless to Wireless
Hedy Lamarr helped to set the groundwork for some
of the most revolutionary technology of our time.
Following the outbreak of World War II, Lamarr, a
passionate opponent of the Nazis, wanted to contribute more to the
allied effort. As Mrs. Fritz Mandl, she had closely observed the
planning and discussions that went into attempting to design
remote-controlled torpedoes. These never went into production, because
the radio-controlled guidance system was too susceptible to disruption.
She got the idea of distributing the torpedo guidance signal over
several frequencies, thus protecting it from enemy jamming. The only
weak point was how to employ the synchronization of the signal's
transmitter and receiver. In
1940, Lamarr met the American avant-garde composer George Antheil of
"ballet mécanique" fame. She described her idea to him, and asked him
to help her construct a device that would enable this signal to be
synchronized. Antheil laid out a system based on 88 frequencies,
corresponding to the number of keys on a piano, using perforated paper
rolls which would turn in sync with one another, transmitting and
receiving ever-changing frequencies, preventing interceptance and
jamming. In
December of 1940, the "frequency hopping" device developed by Lamarr
and Antheil was submitted to the national inventors council, a
semi-military inventors' association. Lamarr and Antheil went on to
file for a patent application for the "Secret Communication System,"
June 10, 1941. The patent was granted by the United States patent
office on august 11, 1942.
Lamarr and Antheil immediately placed their patent at the disposal of
the US military. Though the us government did not deploy the "secret
communication system" during World War II, the US Navy commissioned a
project to acoustically detect submarines using sonar buoys
remote-controlled from airplanes employing "frequency hopping" in the
1950s. Twenty
years after its conceptualization, during the 1962 Cuban missile
crisis, the first instance of large-scale military deployment of Lamarr
and Antheil's frequency hopping technology was implemented-- not for
the remote-controlled guidance of torpedoes, but to provide secure
communications among the ships involved in the naval blockade. The
early '60s saw the development of reconnaissance drones based on
frequency hopping, which were later deployed in Vietnam. With the
emergence of digital technology and the military's release of frequency
hopping for public use in the 1980s,
Lamarr and Antheil's invention took on new significance. Instead of
"frequency hopping," today's term is "spread spectrum" but the basic
idea is the same. The FCC recently allotted a special section of the
radio spectrum for an experiment using the spread spectrum idea in a
test designed to make cell phone calls more secure. A lot of corporate
dollars have been invested in this process which has allowed more cell
phone users to use the existing frequency spectrum.
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