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| Hedy Lamarr, inventor of Frequency Hopping Radio |
The early years of World War II were grim. US forces were
deploying torpedoes against Axis ships to little avail. Aerial, shipborne, and
submarine-launched torpedoes were inflicting shockingly little damage against
the enemy. Top US submarine commanders often made dangerous, close approaches
and fired eight or ten torpedoes against enemy ships, none of which exploded.
To say this was frustrating is an extreme understatement.
Sometimes the torpedoes dived too deep and missed
underneath. Often the magnetic explosive heads detected the ship too soon and
exploded prematurely. And occasionally the gyroscopically controlled torpedoes circled
around and became a threat to the US ship or submarine that had launched it. Our
technology sucked.
There were many villains. The Newport, Rhode Island, torpedo
development labs were hamstrung by limited budgets. The Navy didn’t want live
testing because target ships might actually be sunk. The torpedoes themselves
were expensive and scarce, so sacrificing some to test runs was problematic in a tight
budget environment. So the torpedoes given to the fleets were assumed to work
based on engineering models, but were untested. The results were tragic, with many
of our submarines sunk after mounting unsuccessful attacks.
The Navy, realizing that something had to change, began to seriously
explore alternatives, one of which was radio guidance systems. But the problem was
that radio signals could easily be jammed by the enemy. If a torpedo were launched
under radio control, but the enemy jammed the signal, the guidance system
would be rendered inoperative.
Enter Hedwig Eva Maria Kiesler, who with co-inventor George
Antheil, designed a method to prevent the jamming of radio signals. This method
was based on frequency hopping, in which the sending and receiving radios (for instance, submarine and torpedo) would simultaneously and rapidly change
the frequency they used to communicate with each other. This method would render
enemy jamming ineffective, and allow the torpedo to follow the commands of the
controlling US ship, aircraft, or submarine. It was impossible for the enemy to
jam an unpredictable signal with constantly shifting frequencies.
While this technology did not come to fruition during World War
II, it did become useful, in different ways, later.
Frequency hopping is considered the basis for spread spectrum
communication. And this is the technology that allows your cellphone to communicate
with the nearest cellphone tower along with thousands of other cellphones, simultaneously,
without you hearing your neighbor’s salacious gossip. Spread spectrum
transmission provides privacy, eliminates the issue of signal interference, and reduces noise problems. Without this technology, we would be back to the
days of CB radio. 10-4, good buddy!
Hedwig Kiesler, a.k.a. Hedy Lamarr, was an Austrian-born star
of the golden age of cinema. She was a revered poster girl and adorned the
noses cones of multiple B-17 and B-25 bombers. She was the star of many
Hollywood blockbusters in the 40s and 50s, and performed with leading men such
as Clark Gable and Spencer Tracey. She was at once gorgeous and brilliant.
In 1997, she was awarded the Electronic Frontier Foundation
(EFF) Pioneer Award. In 2014, she was posthumously inducted into the Inventors
Hall of Fame. While a beautiful, famous movie star, she was at the same time a
serious scientist. She was said to observe “My face has been a misfortune, a
mask I cannot remove. I must live with it. I curse it.”
She passed away at the dawn of this century on January 19, 2000, almost exactly 18
years ago, after seeing, and being a part of, the sweep of the twentieth. What a wonderful life.
The next time you use your cellphone to check up on your kids,
please thank Hedy.
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