The mother of wifi was a Hollywood legend

Seventy-two years ago this week a patent was filed - number US2292387 - for a "secret communication system".

Its holders were George Antheil and Hedy Lamarr, the latter then one of the most famous actresses in Hollywood.

The patent was designed to retain control of torpedoes without enemy craft discovering what frequency they were on.

But the technology - which has its roots in pianos that played music from perforated paper rolls - was shunned by the US government until the Cuban missile crisis.

Many years later still and the same principle, known as spread-spectrum broadcasting, can be found in wifi networks, smartphones and GPS.

Lamarr was born Hedwig Eva Maria Kiesler in Austria and married a munitions producer whereupon she developed a love of technology and tinkering with things.

Uncomfortable with her husband's growing links to the Nazis she immigrated to the US in 1937 and became a huge star with MGM during its golden age.

Despite starring in a series of hit movies she largely shunned the celebrity lifestyle, instead preferring to return to her inventions in her own time, leading to the patent being developed.

Any girl can be glamorous, all you have to do is stand still and look stupid.

• Hedy Lamarr

Lamarr died in 2000, three years after being awarded the Electronic Frontier Foundation's Pioneer Award, while this year she was inducted into the American National Inventor's Hall of Fame. Forbes describes her as the most glamorous geek of all time.

Her son Anthony Loder said his mother "realised that what she came up with was important but I don't think she knew how important it's going to be".

"The definition of importance is the more people that it affects over the longer period of time. The longer this goes on and the more people it affects the more important she will be," he added.

"She has her place in history now."

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(Picture: Getty)