Nyquist frequency
Nyquist frequency
The Nyquist frequency is a fundamental concept in the field of signal processing and digital signal processing. It is named after the Swedish-American engineer Harry Nyquist, who made significant contributions to the field of telecommunications.
Definition[edit | edit source]
The Nyquist frequency is defined as half of the sampling rate of a discrete signal processing system. It represents the highest frequency that can be accurately represented when a continuous signal is sampled. Mathematically, if the sampling rate is denoted as \( f_s \), the Nyquist frequency \( f_N \) is given by:
\[ f_N = \frac{f_s}{2} \]
Importance[edit | edit source]
The concept of the Nyquist frequency is crucial in the context of the Nyquist-Shannon sampling theorem, which states that a continuous signal can be completely represented in its sampled form and perfectly reconstructed if it is sampled at a rate greater than twice its highest frequency component. This minimum sampling rate is known as the Nyquist rate.
Aliasing[edit | edit source]
If a signal is sampled at a rate lower than the Nyquist rate, aliasing occurs. Aliasing is a phenomenon where higher frequency components of the signal are indistinguishably mapped to lower frequencies, leading to distortion and loss of information. To prevent aliasing, an anti-aliasing filter is often applied to the signal before sampling.
Applications[edit | edit source]
The Nyquist frequency is a key parameter in various applications, including:
- Digital audio and digital video processing
- Telecommunications
- Radar and sonar systems
- Medical imaging techniques such as MRI and CT scans
Related Concepts[edit | edit source]
- Sampling (signal processing)
- Nyquist-Shannon sampling theorem
- Aliasing
- Anti-aliasing filter
- Fourier transform
- Discrete Fourier transform
See Also[edit | edit source]
References[edit | edit source]
Navigation: Wellness - Encyclopedia - Health topics - Disease Index - Drugs - World Directory - Gray's Anatomy - Keto diet - Recipes
Search WikiMD
Ad.Tired of being Overweight? Try W8MD's physician weight loss program.
Semaglutide (Ozempic / Wegovy and Tirzepatide (Mounjaro / Zepbound) available.
Advertise on WikiMD
WikiMD is not a substitute for professional medical advice. See full disclaimer.
Credits:Most images are courtesy of Wikimedia commons, and templates Wikipedia, licensed under CC BY SA or similar.
Translate this page: - East Asian
中文,
日本,
한국어,
South Asian
हिन्दी,
தமிழ்,
తెలుగు,
Urdu,
ಕನ್ನಡ,
Southeast Asian
Indonesian,
Vietnamese,
Thai,
မြန်မာဘာသာ,
বাংলা
European
español,
Deutsch,
français,
Greek,
português do Brasil,
polski,
română,
русский,
Nederlands,
norsk,
svenska,
suomi,
Italian
Middle Eastern & African
عربى,
Turkish,
Persian,
Hebrew,
Afrikaans,
isiZulu,
Kiswahili,
Other
Bulgarian,
Hungarian,
Czech,
Swedish,
മലയാളം,
मराठी,
ਪੰਜਾਬੀ,
ગુજરાતી,
Portuguese,
Ukrainian
Contributors: Prab R. Tumpati, MD