How a Hollywood Star Helped Invent Wi-Fi

One of the most important ideas in modern wireless communication did not come out of a corporate research lab or a defense contractor. It was patented in 1942 by one of the most famous movie stars of the era, working alongside an avant-garde composer. The actress was Hedy Lamarr, and the technique she helped invent, frequency hopping , is a direct ancestor of the Wi-Fi, Bluetooth, and GPS signals your devices rely on every day. The patent Hollywood forgot At the height of her Hollywood fame, Hedy Lamarr was also a self-taught inventor who tinkered between film shoots. Early in World War II she became fixed on a hard problem: radio-controlled torpedoes were easy to jam, because an enemy who found the single control frequency could simply drown it in noise and send the weapon off course. Working with composer George Antheil, she designed a system where the transmitter and receiver would rapidly and secretly switch together across many different frequencies. Antheil, who had once synchronized sixteen player pianos for a concert piece, suggested using a slotted paper roll like a player piano to keep both ends hopping in step across 88 frequencies , the same number as the keys on a piano. On August 11, 1942, they received U.S. Patent 2,292,387 for a "Secret Communication System." The U.S. Navy filed the idea away and did not use it during the war. For decades the patent sat largely forgotten, and Lamarr received no money and little recognition for it in her lifetime. She was finally inducted into the National Inventors Hall of Fame in 2014, years after her death. What frequency hopping actually does The core insight is deceptively simple. Instead of putting a signal on one fixed frequency, you spread it across many frequencies in a pattern that only the sender and receiver know. Both ends "hop" in perfect synchronization, dwelling on each frequency for only a fraction of a second before jumping to the next. This buys you two enormous advantages. It is very hard to jam, b