Harry Nyquist (pron. [nʏ:kvɪst], not [naɪkwɪst] as often pronounced), (February 7, 1889 – April 4, 1976) was an important contributor to information theory. is the 38th day of the year in the Gregorian calendar. ... Year 1889 (MDCCCLXXXIX) was a common year starting on Tuesday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Thursday of the 12-day slower Julian calendar). ... is the 94th day of the year (95th in leap years) in the Gregorian calendar. ... Year 1976 Pick up sticks(MCMLXXVI) was a leap year starting on Thursday (link will display full calendar) of the Gregorian calendar. ... A bundle of optical fiber. ...

He was born in Nilsby, Sweden. He emigrated to the USA in 1907 and entered the University of North Dakota in 1912. He received a Ph.D. in physics at Yale University in 1917. He worked at AT&T's Department of Development and Research from 1917 to 1934, and continued when it became Bell Telephone Laboratories in that year, until his retirement in 1954. Year 1907 (MCMVII) was a common year starting on Tuesday (link will display the full calendar) of the Gregorian calendar (or a common year starting on Monday of the 13-day-slower Julian calendar). ... The University of North Dakota (UND) is a comprehensive, public university in Grand Forks, North Dakota, USA. UND is the largest and oldest university in the state of North Dakota. ... 1912 (MCMXII) was a leap year starting on Monday in the Gregorian calendar (or a leap year starting on Tuesday in the 13-day-slower Julian calendar). ... “Yale” redirects here. ... 1917 (MCMXVII) was a common year starting on Monday of the Gregorian calendar (see link for calendar) or a common year starting on Tuesday of the 13-day slower Julian calendar (see: 1917 Julian calendar). ... AT&T Inc. ... Year 1934 (MCMXXXIV) was a common year starting on Monday (link will display full 1934 calendar) of the Gregorian calendar. ... Bell Telephone Laboratories or Bell Labs was originally the research and development arm of the United States Bell System, and was the premier corporate facility of its type, developing a range of revolutionary technologies from telephone switches to specialized coverings for telephone cables, to the transistor. ...

As an engineer at Bell Laboratories, he 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 classical paper on stability of feedback amplifiers (H. Nyquist, "Regeneration theory", Bell System Technical Journal, vol. 11, pp. 126-147, 1932). Nyquist stability criterion can now be found in all textbooks on feedback control theory. Johnson-Nyquist noise, thermal noise, Johnson noise, or Nyquist noise) is the noise generated by the equilibrium fluctuations of the electric current inside an electrical conductor, which happens regardless of any applied voltage, due to the random thermal motion of the charge carriers (the electrons). ... It has been suggested that this article or section be merged with Feedback loop. ... For the British rock band of the same name, see Amplifier (band). ... Dr. Herbert Eugene Ives (1882–1953) was a scientist and engineer who headed the development of facsimile and television systems at AT&T in the first half of the twentieth century. ... AT&T Inc. ... The Nyquist plot for . ...

His early theoretical work on determining the bandwidth requirements for transmitting information, as published in "Certain factors affecting telegraph speed" (Bell System Technical Journal, 3, 324–346, 1924), laid the foundations for later advances by Claude Shannon, which led to the development of information theory. Bell System Technical Journal was the in-house journal of Bell Laboratories. ... Year 1924 (MCMXXIV) was a leap year starting on Tuesday (link will display the full calendar) of the Gregorian calendar. ... Claude Shannon Claude Elwood Shannon (April 30, 1916 – February 24, 2001), an American electrical engineer and mathematician, has been called the father of information theory,[1] and was the founder of practical digital circuit design theory. ... A bundle of optical fiber. ...

In 1927 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. Nyquist published his results in the paper Certain topics in Telegraph Transmission Theory (1928). This rule is essentially a dual of what is now known as the Nyquist–Shannon sampling theorem. Year 1927 (MCMXXVII) was a common year starting on Saturday (link will display full calendar) of the Gregorian calendar. ... This article does not cite any references or sources. ... Year 1928 (MCMXXVIII) was a leap year starting on Sunday (link will display full calendar) of the Gregorian calendar. ... In mathematics, duality has numerous meanings. ... The Nyquist–Shannon sampling theorem is a fundamental result in the field of information theory, in particular telecommunications and signal processing. ...

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." The IEEE Medal of Honor is the highest recognition of the IEEE, and has been awarded once each year since 1917, when its first recipient was Major Edwin H. Armstrong. ... Franklin Institute Front steps as seen from the adjacent Moore College This article is about the science museum in Philadelphia. ... Founded in 1964, the National Academy of Engineering (NAE) in the United States provides engineering leadership in service to the nation. ...

Nyquist lived in Pharr, Texas after his retirement, and died in Harlingen, Texas on April 4, 1976. Pharr is a city located in Hidalgo County, Texas, United States. ... Harlingen is a city in Cameron County in the heart of the Rio Grande Valley of south Texas, United States. ... is the 94th day of the year (95th in leap years) in the Gregorian calendar. ... Year 1976 Pick up sticks(MCMLXXVI) was a leap year starting on Thursday (link will display full calendar) of the Gregorian calendar. ...

See also

• Nyquist plot
• Nyquist–Shannon sampling theorem
• Nyquist frequency
• Nyquist stability criterion
• Nyquist ISI criterion
• Johnson–Nyquist noise

A Nyquist plot is a graph used in signal processing in which the magnitude and phase of a frequency response are plotted on orthogonal axes. ... The Nyquist–Shannon sampling theorem is a fundamental result in the field of information theory, in particular telecommunications and signal processing. ... The Nyquist frequency, named after Harry Nyquist or the Nyquist–Shannon sampling theorem, is half the sampling frequency of a discrete signal processing system. ... The Nyquist plot for . ... In communications, the Nyquist ISI criterion describes the conditions which, when satisfied by a communication channel, result in no intersymbol interference or ISI. When consecutive symbols are transmitted over a channel by a linear modulation (such as ASK, QAM, etc. ... Johnson–Nyquist noise (thermal noise, Johnson noise, or Nyquist noise) is the noise generated by the thermal agitation of the charge carriers (the electrons) inside an electrical conductor in equilibrium, which happens regardless of any applied voltage. ...

External links

• IEEE page about Nyquist
• Nyquist criterion page with photo of Nyquist with John R. Pierce and Rudy Kompfner