Harry Nyquist
Harry Nyquist (
February 7,
1889 â€"
April 4,
1976) was an important contributor to
information theory.
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 from 1917 to
1934, then moved to
Bell Telephone Laboratories.
As an engineer at Bell Laboratories, he did important work on thermal noise ("
Johnsonâ€"Nyquist noise") and the stability of
feedback amplifiers.
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, 324â€"346,
1924), laid the foundations for later advances by
Claude Shannon, which led to the development of
information theory.
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
Nyquistâ€"Shannon sampling theorem.
Nyquist received the
IRE Medal of Honor in 1960 for "fundamental contributions to a quantitative understanding of thermal noise, data transmission and negative feedback."
He retired from Bell Labs in
1954.
Nyquist died in
Harlingen, Texas on
April 4,
1976.
*
Nyquist plot*
Nyquistâ€"Shannon sampling theorem*
Nyquist frequency*
Nyquist stability criterion*
Nyquist ISI criterion*
Johnsonâ€"Nyquist noise*
IEEE page about Nyquist*
Nyquist criterion page with photo of Nyquist with
John R. Pierce and
Rudy Kompfner
