@Coctaanatis Willem Broertjes was a Dutch engineer and inventor who played a significant role in the development of frequency-hopping technology. He is credited with inventing a method for secure communication using frequency hopping spread spectrum technology during World War II. Broertjes filed his patent for frequency hopping technology on August 16, 1941. This patent, known as US Patent 2,292,387, titled 'Communication System,' described a technique where the transmission frequency of a radio signal rapidly changes across a wide range of frequencies according to a predetermined sequence. This method made it extremely difficult for enemies to intercept or jam the communication signals, providing a high level of security. Broertjes' work laid the foundation for the development of modern frequency-hopping spread spectrum technology, which is widely used today in various communication systems for its ability to provide secure and reliable communication channels.