Harald T. Friis

Source: Wikipedia, the free encyclopedia.
Harald Trap Friis
Born22 February 1893
Næstved, Zealand, Denmark
Died15 June 1976 (1976-06-16) (aged 83)
Palo Alto, California, United States
NationalityAmerican
Alma mater
Known for
Awards
Scientific career
FieldsElectrical engineering
InstitutionsBell Labs

Harald Trap Friis (22 February 1893 – 15 June 1976), who published as H. T. Friis, was a

Bell Laboratories included pioneering contributions to radio propagation, radio astronomy, and radar.[1] His two Friis formulas remain widely used.[2]

Background

Friis was born in

Western Electric Company
research group which in 1925 became part of Bell Laboratories. There he remained for his entire professional career. [3]

Career

Friis' first important publications were his 1923 Institute of Radio Engineers (IRE) paper on radio transmission measurements, 1925 IRE paper on directional antennas, and 1928 IRE paper on oscillographic observations of propagation phenomena. These papers documented studies of field strength and noise over a wide range of frequencies and stressed the importance of the signal-to-noise ratio (SNR) in receivers rather than simple field strength.

During the early 1930s Friis helped design the radio receiver used by

Teal, 1942).[4]

In 1946 Friis published his well-known analytic formula for transmission loss, the

Hewlett-Packard Company as a friend of David Packard
. He held 31 U.S. patents.

Friis died on 15 June 1976, at age 83, of a stroke in Palo Alto, California.[1]

Awards

Friis received the IRE Morris N. Liebmann Award in 1939, the IRE Medal of Honor (now the IEEE Medal of Honor) in 1955, the Valdemar Poulsen Gold Medal of the Danish Academy of Technical Sciences [da] in 1956, the Stuart Ballantine Medal from the Franklin Institute in 1958 and the Mervin Kelly Award of the IEEE in 1964.[5]

Selected works

  • Seventy Five Years in an Exciting World, (1971)
  • Antennas: Theory and Practice, (1952) – with Sergei A. Schelkunoff
  • Proceedings of the IRE, vol. 34, p. 254, (1946) – Friis transmission equation
  • A New Directional Receiving System, (1925)
  • High Frequency Amplifiers, (1924)

Work papers

The papers of Harald Trap Friis span the years 1921-1976. These documents are available to the public and are maintained at the Manuscript Division, Library of Congress, Washington, D.C.[6]

References

  1. ^ a b c "Died". Time. 28 June 1976. Archived from the original on 20 February 2011. Retrieved 2008-04-28.
  2. doi:10.1038/262826b0
    . Retrieved 10 March 2016.
  3. ^ Pierce, John Robinson (1957). The Wisdom of Harald Friis.
  4. ^ "Harald T. Friis (1893-1976)" (PDF). Library of Congress. Retrieved 10 March 2016.
  5. ^ "H. T. Friis, 1955, Spectrum of radio frequencies, leadership". IRE Medal of Honor Winners 1917-1963. Retrieved 10 March 2016.
  6. ^ "Harald T. Friis papers, 1921-1976". Manuscript Division. Washington, DC: Library of Congress. Retrieved 10 March 2016.

Other sources

  • Teal, Gordon K. (July 1976). "Single Crystals of Germanium and Silicon—Basic to the Transistor and Integrated Circuit". IEEE Transactions on Electron Devices. 23 (7). IEEE: 621–639.
    S2CID 11910543
    .
Retrieved from "https://en.wikipedia.org/w/index.php?title=Harald_T._Friis&oldid=1218961285"