Sneha Girap (Editor)

Harry Nyquist

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Residence
  
United States

Role
  
Engineer

Nationality
  
American

Fields
  
Electronic engineering


Institutions
  
Bell Laboratories

Name
  
Harry Nyquist

Awards
  
IEEE Medal of Honor

Harry Nyquist httpsuploadwikimediaorgwikipediaenthumbb

Born
  
February 7, 1889 Stora Kil, Nilsby, Varmland, Sweden (
1889-02-07
)

Alma mater
  
Yale University University of North Dakota

Known for
  
Nyquist–Shannon sampling theorem Nyquist rate Johnson–Nyquist noise Nyquist stability criterion Nyquist ISI criterion Nyquist plot Nyquist frequency Nyquist filter Fluctuation dissipation theorem

Died
  
April 4, 1976, Harlingen, Texas, United States

Education
  
Yale University, University of North Dakota

Notable awards
  
IEEE Medal of Honor (1960), Stuart Ballantine Medal (1960), Rufus Oldenburger Medal (1975)

Doctoral advisor
  
Henry A. Bumstead

Harry nyquist


Harry Nyquist ( Harry Theodor Nyqvist , [nyːkvɪst]; February 7, 1889 – April 4, 1976) was a Swedish born American electronic engineer who made important contributions to communication theory.

Contents

Personal life

Nyquist was born in the Stora Kil parish of Nilsby, Värmland, Sweden. He was the son of Lars Jonsson Nyqvist (b. 1847) and Katrina Eriksdotter (b. 1857). His parents had seven children: Elin Teresia, Astrid, Selma, Harry Theodor, Aemelie, Olga Maria, and Axel. He emigrated to the USA in 1907.

Education

He entered the University of North Dakota in 1912 and received B.S. and M.S. degrees in electrical engineering in 1914 and 1915, respectively. He received a Ph.D. in physics at Yale University in 1917.

Career

He worked at AT&T's Department of Development and Research from 1917 to 1934, and continued when it became Bell Telephone Laboratories that year, until his retirement in 1954.

Nyquist received the IRE Medal of Honor in 1960 for "fundamental contributions to a quantitative understanding of thermal noise, data transmission and negative feedback." In October 1960 he was awarded the Stuart Ballantine Medal of the Franklin Institute "for his theoretical analyses and practical inventions in the field of communications systems during the past forty years including, particularly, his original work in the theories of telegraph transmission, thermal noise in electric conductors, and in the history of feedback systems." In 1969 he was awarded the National Academy of Engineering's fourth Founder's Medal "in recognition of his many fundamental contributions to engineering." In 1975 Nyquist received together with Hendrik Bode the Rufus Oldenburger Medal from the American Society of Mechanical Engineers.

Nyquist lived in Pharr, Texas after his retirement, and died in Harlingen, Texas on April 4, 1976.

Technical contributions

As an engineer at Bell Laboratories, Nyquist did important work on thermal noise ("Johnson–Nyquist noise"), the stability of feedback amplifiers, telegraphy, facsimile, television, and other important communications problems. With Herbert E. Ives, he helped to develop AT&T's first facsimile machines that were made public in 1924. In 1932, he published a classic paper on stability of feedback amplifiers. The Nyquist stability criterion can now be found in all textbooks on feedback control theory.

His early theoretical work on determining the bandwidth requirements for transmitting information laid the foundations for later advances by Claude Shannon, which led to the development of information theory. In particular, Nyquist determined that the number of independent pulses that could be put through a telegraph channel per unit time is limited to twice the bandwidth of the channel, and published his results in the papers Certain factors affecting telegraph speed (1924) and Certain topics in Telegraph Transmission Theory (1928). This rule is essentially a dual of what is now known as the Nyquist–Shannon sampling theorem.

Terms named for Harry Nyquist

  • Nyquist rate: sampling rate of twice the bandwidth of a signal; sampling faster than this rate assures the signal can be reconstructed exactly.
  • Nyquist frequency: half the sample rate of a system; signal frequencies below this value are unambiguously represented.
  • Nyquist filter
  • Nyquist plot
  • Nyquist ISI criterion
  • Nyquist (programming language)
  • Nyquist stability criterion
  • References

    Harry Nyquist Wikipedia