Harald T. Friis

Harald Trap Friis
Harald Trap Friis
Born	22 February 1893; Næstved, Zealand, Denmark
Died	15 June 1976 (aged 83); Palo Alto, California, United States
Alma mater	Technical University of Denmark; Columbia University;
Known for	Friis transmission equation; Friis formulas for noise; Horn-reflector antenna; Rhombic antenna;
Awards	Stuart Ballantine Medal (1958); Valdemar Poulsen Medal (1956); IEEE Medal of Honor (1955); IRE Morris Liebmann Memorial Prize (1939);
	Scientific career
Fields	Electrical engineering
Institutions	Bell Labs

Harald Trap Friis (22 February 1893 – 15 June 1976), who published as H. T. Friis, was a Danish-American radio engineer whose work at Bell Laboratories included pioneering contributions to radio propagation, radio astronomy, and radar. His two Friis formulas remain widely used.