Austrian and American actress Hedy Lamarr, the prototype for Disney’s Snow White, was renowned not only for her beauty but also for her intelligence. During World War II, when she could no longer act in films and promote war bonds, she invented technology that is now used in Wi-Fi, GPS, and Bluetooth.
One of the most beautiful women in the world, Hedy Lamarr was born to a Jewish family in Vienna. There, she gained worldwide but controversial fame for appearing nude in the film “Ecstasy,” which was condemned by the Pope and banned by Hitler. Four years later, the actress, then known as Hedwig Kiesler, fled to London to escape growing anti-Semitism and her first marriage to a military magnate with Nazi ties.
In London, she met Louis B. Mayer, one of the founders of the Metro-Goldwyn-Mayer film studio. Learning that Mayer was returning to New York, she bought a ticket on the same liner. She disembarked with a contract and a new name, as Mayer advised her to change her name to avoid being associated with “Ecstasy” in the eyes of Americans.
In Hollywood, Hedy Lamarr quickly rose through the ranks, starring in films such as “Algiers,” “Lady of the Tropics,” and “The Strange Woman,” earning about $30 million.
An Idea Ahead of Its Time
In 1939, World War II began, and Hedy Lamarr wanted to help her new homeland. The actress was used for her specialty—promoting defense bonds, with buyers of $7,000 worth receiving a kiss from the beauty. However, Hedy knew she could help America in other ways. She had loved science since childhood, and with the start of the war, along with her lover, engineer Howard Hughes, she began thinking about how to increase the speed of military aircraft.
Radio Transmission Technology with Anti-Jamming Protection
Lamarr knew that ships in the Atlantic were being sunk by German submarines. There was a problem with controlling torpedoes due to the Germans intercepting target coordinates. This led Hedy to think about creating radio transmission technology with anti-jamming protection. She approached the National Inventors Council in the USA, but her proposal was not supported.
In the summer of 1940, Hedy met George Antheil, a popular Hollywood pianist and composer who also wanted to help in the fight against fascism. Playing piano duets gave them the idea of sending parts of a signal on one frequency and then switching to another. If the transmitter and receiver were synchronized in advance, the signal could become resistant to jamming. They called their idea “frequency-hopping spread spectrum.”
They decided to test their theory on a mechanical piano, as their idea was to synchronize the transmitter and receiver using a roll from the instrument. It was small enough to fit into a torpedo, which this invention was intended for. The rotating roll set the course encoded on a punched tape, which was a data carrier with holes. A short radio signal transmitted its rotation to the torpedo’s roll, automatically setting the course.
Similar pseudorandom codes had been used before but were transmitted over open channels, making them easy to intercept. Now, a special key was required for both transmission and reception. The Germans couldn’t jam all 88 frequencies (the number of piano keys), and calculating the correct frequency would take too long.
In December, they filed a patent application with the National Inventors Council, labeling it “Secret Communication System.” Hedy and George received a patent for their invention but waived royalties, transferring the technology to the US government. However, the project was difficult to implement practically, so the patent was shelved and forgotten.
A Second Chance
During the Cuban Missile Crisis, the invention was revisited. With advances in electronics, Lamarr and Antheil’s idea was reworked to include semiconductor components instead of mechanical ones. This led to the concept of “spread spectrum”—a wide range of frequencies, high data throughput, and resistance to interference.
In the late 1980s, the Pentagon declassified several patents, making them available for civilian use.
CDMA radio telephone communication was one of the first technologies to apply the spread spectrum concept. Each user is assigned a unique numerical code, which the receiver and transmitter separate from the total number of radio signals and connect. This is similar to a conversation in a café—ears pick up conversations at other tables and music, but focus on the voice of the person you are speaking with. Today, all mobile phone operators, as well as GPS, Bluetooth, and Wi-Fi technologies, work on similar principles.
Patent No. 2,292,387, issued to Hedy Kiesler Markey (her married name) and George Antheil.