The communication method known as Spread Spectrum transmission was invented by none other than Hedy Lamarr, the internationally known actress whose many roles included the character of "Tondelayo" in the 1942 movie "White Cargo."

Hedy Lamarr (1913-2000), along with her co-inventor, musician George Antheil (1900-1959), came up with the idea of "frequency hopping" as a method of shifting radio signals quickly to make them less vulnerable to radio interference and jamming. Lamarr, who had no technical education, developed her theories during the 1930's in Austria by observing her first husband's research efforts on German wireless torpedo launchers. When she left him to come to Hollywood, she learned of George Antheil and his mechanical musical compositions using multiple player pianos. Lamarr's idea of using multiple, randomly changing frequencies for sending messages securely between the transmitter and receiver was combined with Antheil's method of sound synchronization to solve the problem of synchronizing the frequencies used by the 2 radios.

Lamarr applied for a patent on this new "spread spectrum" technology using her married name of "H. K. Markey" in 1941. US Patent number 2292387, for a "Secret Communication System," was granted on Aug. 1, 1942. Lamarr signed the application "Hedy Kiesler Markey," combining Keisler, her maiden name, with second husband Gene Markey's last name. Lamarr was her stage name.

Lamarr gave her Secret Communication System to the US government in support of the World War II efforts for secure military communication purposes. After the war, Sylvania Electronic Systems Division replaced the mechanically driven paper rolls with digital components to make spread spectrum systems more reliable. However, Hedy never received any compensation or official thanks from the Army or Navy, and her invention remained a secret until 1963 when the patent expired and became public domain.

Spread spectrum systems take a narrow band signal and spreads it across several frequencies using one of the five encoding methods. This process has significant military advantages because a signal from a spread spectrum system is harder to detect and jam. Spread spectrum also allows very efficient use of the bandwidth because multiple systems can occupy the same frequency space without interfering with each other.

The same features that were highly coveted by the military during World War II are now in demand in the highly competitive commercial market. Spread spectrum technologies are found in wireless ethernet links, cordless telephones, GPS devices, PCS devices, and digital cellular telephony (CDMA).

Systemonic has named the 5GHz chipset, Tondelayo, as a tribute to the memory of Ms. Lamarr and her considerable contribution to this country and to our industry.

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