Reinhold Rudenberg (or Rüdenberg; February 4, 1883 – December 25, 1961) was a German-American electrical engineer and inventor, credited with many innovations in the electric power and related fields.[1] Aside from improvements in electric power equipment, especially large alternating current generators, among others were the electrostatic-lens electron microscope, carrier-current communications on power lines, a form of phased array radar, an explanation of power blackouts, preferred number series, and the number prefix "Giga-".[citation needed]