Ikigai Daily
Menu
WonderTechnology fact

In 1942 the actress Hedy Lamarr and the composer George Antheil patented a way to stop enemies jamming radio-controlled torpedoes: the signal kept hopping between frequencies. Bluetooth uses frequency hopping today.

US patent 2,292,387, 1942

TechnologyBiography

The story behind the card

Born in Vienna in 1914, Lamarr became a Hollywood star billed as the most beautiful woman in the world, but she was bored by her roles and kept an inventing table at home. Antheil, known for a piece written for synchronised player pianos, suggested using punched rolls like a pianola's to keep the transmitter and the torpedo hopping in step across 88 frequencies, the number of keys on a piano. The US Navy shelved the idea, and the patent expired without earning either of them anything. Frequency hopping later became common in military and civilian radio, including Bluetooth. Lamarr was inducted into the US National Inventors Hall of Fame in 2014, fourteen years after her death.

Türkçe oku
Oyuncu Hedy Lamarr ile besteci George Antheil 1942'de, düşmanın radyoyla yönlendirilen torpidoların sinyalini bozmasını önleyen bir yöntemin patentini aldı: Sinyal sürekli frekans değiştiriyordu. Bugün Bluetooth da bu frekans atlama ilkesini kullanıyor.
ABD patenti 2.292.387, 1942

1914'te Viyana'da doğan Lamarr, Hollywood'da “dünyanın en güzel kadını” diye tanıtılan bir yıldız oldu; ama oynadığı rollerden sıkılıyor, evinde icatları için ayrı bir masa tutuyordu. Otomatik piyanolar için yazdığı bir eserle tanınan Antheil, verici ile torpidonun 88 frekans arasında aynı sırayla atlamasını, pianola rulolarına benzer delikli şeritlerle sağlamayı önerdi; 88, piyanodaki tuş sayısıydı. ABD Donanması fikri rafa kaldırdı, patentin süresi de ikisine bir kuruş kazandırmadan doldu. Frekans atlama sonradan askerî ve sivil telsiz iletişiminde yaygınlaştı; Bluetooth da bu yöntemi kullanıyor. Lamarr, ölümünden on dört yıl sonra, 2014'te ABD Ulusal Mucitler Onur Listesi'ne alındı.

Sources and further reading

Background reading: Hedy Lamarr
Get the mobile appAbout our cards

Related cards

These cards share a subject or reading mode with the card above.

DriveBiography

Fazlur Rahman Khan, a Bangladeshi-American structural engineer, made very tall buildings cheaper to build with his 'tube' systems, in which a tower's outer walls work together to resist the wind. They shaped Chicago's John Hancock Center and the Sears Tower, now Willis Tower.

Before Khan, most skyscrapers relied on a rigid internal frame of steel columns and beams, and the taller they went, the more steel they needed to keep them from swaying in the wind. In Khan's framed tube, columns are set close together around the outside of the building and tied by deep beams called spandrels, so the whole outer wall acts like one stiff, hollow tube anchored in the ground. Working at the Chicago firm Skidmore, Owings & Merrill, he developed variations: the John Hancock Center (1969) braces its tube with giant diagonal X-shapes, and the Sears Tower (1973) bundles nine tubes together. Khan was born in Dhaka in 1929 and died in 1982.

Fazlur Rahman KhanRead card
WonderScience

Gladys West, a mathematician at a US Navy laboratory, programmed computers to build ever more accurate models of the Earth's true shape from satellite data. That work helped lay the groundwork for satellite navigation systems such as GPS.

West grew up on her family's farm in rural Virginia and won a scholarship to Virginia State College. In 1956 she was hired as a mathematician at the Naval Proving Ground in Dahlgren, Virginia, where she stayed for 42 years. The Earth is not a perfect sphere: it bulges at the equator, and its gravity varies from place to place. Scientists describe its true shape with the geoid, the surface the oceans would take under gravity alone, and positions and heights are measured against it. From the mid-1970s West programmed an IBM Stretch computer to calculate this shape ever more precisely, using data from satellites such as Seasat, whose radar altimetry project she managed, and Geosat. Her role became widely known only in 2018, when she was inducted into the US Air Force Space and Missile Pioneers Hall of Fame.

Gladys WestRead card
DriveBiography

Christine Darden, a NASA engineer, wrote computer programs to predict sonic booms, the thunder-like bangs made by aircraft flying faster than sound. Her research showed that reshaping a plane's nose and wings could make them softer on the ground.

Darden, a mathematics graduate of Hampton Institute, joined NASA's Langley Research Center in 1967 as a 'human computer', doing calculations for engineers. She pressed her managers to move her into engineering, and in the 1970s they did. A sonic boom forms when the shock waves from an aircraft's nose, wings and tail merge into one sharp jolt that reaches the ground. Darden's programs modelled those waves and pointed to shapes that keep them from merging, so people below hear a softer thump. She earned a doctorate in engineering from George Washington University in 1983, led NASA's sonic boom team from 1989 and wrote more than 50 papers. NASA's X-59, which first flew on 28 October 2025, was built to test this idea. Her story is also told in Margot Lee Shetterly's book Hidden Figures.

Christine DardenRead card
DriveBiography

Annie Easley joined NACA, NASA's forerunner, in 1955 as a 'human computer' doing calculations by hand, then became a programmer. Her code supported the Centaur rocket stage, which later sent probes such as Voyager and Cassini into space, and research on energy and batteries.

Easley was born in Birmingham, Alabama, in 1933. When she joined the Lewis Flight Propulsion Laboratory in Cleveland, Ohio, she was one of only four Black employees among about 2,500. As machines took over the arithmetic, she learned the programming languages FORTRAN and SOAP. Centaur, a rocket stage that fires after the first stage is spent, was the first to burn liquid hydrogen with liquid oxygen, and her programs supported its analyses. Her energy work included simulations that supported early battery research for hybrid vehicles. She finished a mathematics degree at Cleveland State University in 1977 while working full time. As an equal employment opportunity counsellor, she helped resolve discrimination complaints, and she encouraged girls and minority students to take up science. She retired in 1989.

Annie EasleyRead card
DriveBiography

Evelyn Boyd Granville, one of the first Black American women to earn a PhD in mathematics, wrote computer programs at IBM that calculated orbits for Vanguard and Mercury, the early US satellite and crewed spaceflight projects. She later worked on the Apollo programme.

Granville grew up in Washington, D.C., studied mathematics and physics at Smith College and earned her doctorate at Yale in 1949. Among Black American women, only Euphemia Lofton Haynes, in 1943, had earned a mathematics PhD before her; Marjorie Lee Browne finished hers the same year. Top academic posts were closed to Black women, so she taught at Fisk University, then joined IBM in 1956. At its Vanguard Computing Center in Washington she turned the mathematics of orbits into computer programs, and she later worked on trajectory calculations for Apollo at North American Aviation. From 1967 she was a professor at California State University, Los Angeles, co-wrote a textbook on mathematics for teachers and ran maths enrichment programmes for young children. She died in 2023, aged 99.

Evelyn Boyd GranvilleRead card
Next card in the archiveIn April 1970 an oxygen tank exploded on Apollo 13, more than 300,000 km from Earth, forcing the three astronauts into a lunar module built for two. Engineers on the ground then had to make the command module's square air filters fit the lunar module's round sockets, using only what was aboard.Read next →