Armstrong, Edwin Howard (1890-1954), an American electrical engineer and inventor, made important contributions to electronics and radio communication. In 1933, he introduced the frequency modulation, or FM, broadcasting system that is still in use today. This system provided better sound reproduction and less static interference than the older amplitude modulation, or AM (see Frequency modulation). Earlier, in 1918, Armstrong developed the superheterodyne radio receiver, which became widely used. In 1921, he developed the superregenerative receiver that came into use in mobile radio and other systems. Armstrong was born on Dec. 18, 1890, in New York City. He died on Jan. 31, 1954.