From Hollywood to Frequency Hopping
Hedy Lamarr (1914-2000) lived a double life that few people knew about. To the public, she was a glamorous Austrian-American movie star, one of the most famous faces in Hollywood. Away from the cameras, she was a self-taught inventor who spent her spare time solving technical problems.
During World War II, Lamarr wanted to help the war effort. Radio-controlled torpedoes had a serious weakness: the enemy could 'jam' the single radio frequency guiding them, scrambling the signal and sending the torpedo off course. Working with composer George Antheil, Lamarr designed a solution in which the transmitter and receiver would rapidly switch, or 'hop,' among many frequencies in a shared secret pattern.
This technique is called frequency hopping spread spectrum. Because the signal never stays on one frequency for long, an enemy cannot easily find it, jam it, or intercept it. Lamarr and Antheil patented the idea in 1942 as U.S. Patent 2,292,387.
For decades, few took Lamarr seriously as an inventor because she was known mainly as a beautiful actress. Yet her frequency-hopping concept became a foundation for modern wireless technology, including WiFi, Bluetooth, and GPS. In 2014 she was inducted into the National Inventors Hall of Fame, and today she is sometimes called 'the mother of WiFi.'
