The Hollywood Actress Who Invented Wi-Fi

In August of 1942, the United States Patent Office granted patent US2292387 to two applicants: a composer named George Antheil, and one Hedy Kiesler Markey, of Beverly Hills. Mrs. Markey was better known by her stage name. Hedy Lamarr was, at that point, under contract to MGM and had recently been described in the studio's publicity materials as "the most beautiful woman in the world." The patent had nothing to do with that.

Title: Secret Communication System. The mechanism: a transmitter and receiver that hopped together across 88 different radio frequencies, in a sequence dictated by a synchronized punched-paper roll. The number 88 was not arbitrary; Antheil had built his career on synchronized player pianos, and the number of keys on a piano is 88.

The intended use was torpedo guidance. The Allies had a problem in 1942: radio-controlled torpedoes were susceptible to jamming, and a jammed torpedo missed. If the transmitter and receiver hopped frequencies fast enough, no jammer could keep up. The signal would be back on a fresh channel before the jammer found the previous one.

The Navy filed it away

Lamarr and Antheil submitted the design to the National Inventors Council in 1940. The Council passed it to the Navy. The Navy classified it, decided the mechanism was too complex to fit in a torpedo of the era, and took no further action during the war. The patent expired in 1959 without ever being used for its stated purpose.

How Lamarr knew about torpedo design is, by itself, a longer story. Before fleeing to Hollywood she had been married to Friedrich Mandl, an Austrian munitions manufacturer who supplied weapons to fascist governments across Europe. She sat through dinners with weapons engineers for years. She remembered.

What it became

The Navy revived the technology in 1962, during the Cuban Missile Crisis blockade, on ships intercepting Soviet vessels. By then the patent had expired and the mechanism could be built freely. Through the 1980s and 1990s, frequency hopping became foundational for spread-spectrum wireless communication of nearly every kind: GPS, military radio, Wi-Fi, Bluetooth, and the early cellular networks. Every device in your house that talks wirelessly to another device is, in a real sense, executing the principle described in US2292387.

Lamarr received almost no credit for any of it during her lifetime. The Electronic Frontier Foundation gave her a Pioneer Award in 1997, when she was eighty-two. She was inducted into the National Inventors Hall of Fame in 2014, fourteen years after her death.

See the original

The full text of US2292387 — including the surprisingly elegant player-piano-roll synchronization mechanism — is on patents.us.