Dawn had just cracked, and America was waking up to the sound of crashing waves and the call for duty. Just two years before, World War II had broken out. In one incident alone in 1940, 293 lives were lost, including 83 children, when a ship was torpedoed. The Axis had more advanced military technology and were highly skilled in triumphing over the Allies. Almost all hope seemed lost for America, and the Nazis were about to win the war.

Hedy Lamarr was in front of her inventing table in her house that morning. She was trying to help the Allies with a different approach instead of the typical war bonds. She sketched several detailed diagrams of communication systems to help solve the ongoing problem.

Hedy Lamarr was an iconic actress and little-known inventor in the 20th century. While she was known for her great beauty, very few knew about her intellectual side. She had always been adroit and inquisitive. When she was five, Hedy would take apart and reassemble a music box to understand the machinery behind it.

As Hedy grew into an adult, her experiences in engineering became more sophisticated. She helped aviator Howard Hughes design the world’s fastest airplane by changing the airplane’s wing structure. Surprisingly, Hedy was not formally trained in any of these fields.

Hedy constantly thirsted for knowledge and submerged herself in intellectual content. It was how she learned about torpedoes and their communication using radio systems. In one encounter, Hedy put that knowledge to use. While conversing with composer George Antheil, Hedy realized they were changing frequencies when talking. Using her knowledge of how torpedoes operate on one frequency, she thought constantly “hopping” between frequencies would be much harder to jam and hack. Together, they came up with the idea of a torpedo guidance system.

When WWII hit America, Hedy wanted to help. The Axis were constantly sending attacks on the Allies and deflecting torpedo attacks through skilled hacking. They jammed the radio signals that controlled the Allies’ torpedoes.

Torpedoes were controlled by using electromagnetic waves of one high frequency alone. Any station set to that frequency would be able to receive the signal and control the torpedo. Hedy thought of a plan to protect radio communications with Allie torpedoes so it was nearly impossible to jam the signal. By this, torpedoes would be guided smoothly without any interference.

That is when it struck her. Hedy thought the frequency hopping idea could serve as a solution and plan. Instead of just one frequency directing the torpedo, there would be several. That way, even if one frequency were blocked, the torpedo would only be jammed for a short time before recovering.

Theoretically, it would be impossible to sink the torpedo and avoid the attack. Hedy believed this could be a potential solution. If this idea succeeded, it would be a turning point in the war, and the Allies could win.

However, the road to discovery was not a smooth path. Along the way, Hedy faced many challenges. One of which was that they needed the transmitter and the receiver to be on the same frequency, even with the constant change. She overcame that obstacle by changing the frequency of both the transmitter and the receiver. She successfully developed a radio-controlled system for guiding Allied torpedoes using a frequency-hopping mechanism.

Even with this amazing invention, Hedy’s work was not received well at the time. It was regarded as cumbersome and unreliable and was not used in WWII. Nevertheless, decades later, it proved its use. In the 1960’s Cuban Missile Crisis, frequency hopping was used to guide and protect all US torpedoes.

Hedy’s frequency hopping technology changed our lives. It is now the basis of much of our modern-world technology, such as Wi-Fi, Bluetooth, cell phones, military equipment, GPS, and many more. We can thank Hedy Lamarr for her contribution to our lives and engineering.