What was the initial wartime purpose of the frequency-hopping spread spectrum technology co-invented by Hedy Lamarr?

Answer

To prevent the jamming of radio-controlled torpedoes.

Lamarr and Antheil developed frequency-hopping technology during World War II specifically to maintain the control signal integrity of radio-guided torpedoes against enemy jamming attempts.

What was the initial wartime purpose of the frequency-hopping spread spectrum technology co-invented by Hedy Lamarr?
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