It was back in 1941 when Hedy Lamarr, an Austria born actress, together with George Antheil co-patented a “secret communication system” which allowed radio control of torpedoes that could not be easily discovered, deciphered or jammed.

Her secret: frequency hopping! Coordinated, rapid changes in radio frequencies would literally “hop” in the radio spectrum, thus evading detection and the potential of interference, in other words, being suppressed or jammed.

Even though her idea was ahead of its time and not implemented in the U.S. until 1962, when it was used by U.S. military ships during a blockade of Cuba (after the patent had expired), it is now the basis for modern Frequency Hopping Spread Spectrum (FHSS) wireless communication systems.

FHSS wireless systems are very resilient when it comes to impairments such as interference (deliberate or coincidental) and “jamming.” Other effects can be observed when wireless signals travel through space, such as the “multipath” phenomenon, simply because they use only very small amounts of radio spectrum at a time and don’t dwell (or remain) at that frequency long, instead “hop” to another frequency quickly. Statistically, chances are that the signal does not “land” at the interfering frequency, thereby successfully evading the jamming signal. This makes Denial of Service (DoS) attacks on FHSS systems very difficult, albeit not completely impossible.

Information Pioneers – Hedy Lamarr Edition

As part of BCS, The Chartered Institute for IT video series, Miranda Raison presents Hedy Lamarr for the “Information Pioneers” series and dives deeper into the history behind one of wireless communication’s leading ladies who, together with George Antheil, pioneered the beginning of a communication revolution. Hedy Lamarr would’ve been 101 years old this November.

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