Front cover of Picturegoer magazine, 30th March 1940 featuring Austrian-born American film actress and inventor Hedy Lamarr. As well as being an MGM contract player, Lamarr is also credited with being an inventor. At the beginning of World War II, she and composer George Antheil developed a radio guidance system for Allied torpedoes, which used spread spectrum and frequency hopping technology to defeat the threat of jamming by the Axis powers. Although the US Navy did not adopt the technology until the 1960s, the principles of their work are arguably incorporated into Bluetooth technology, and are similar to methods used in legacy versions of CDMA and Wi-Fi.