Associated with all electronic circuits is noise. Types of noise include This is a Root page. ... Four thousandths of a second of white noise White noise ( (help· info)) is a random signal (or process) with a flat power spectral density. ... Pink noise ( (help· info)), also known as 1/f noise, is a signal or process with a frequency spectrum such that the power spectral density is proportional to the reciprocal of the frequency. ... When speaking of acoustic noise, or noise in relation to sound, what is commonly meant is meaningless sound of greater than usual volume. ... Environmental Noise, is unwanted sound, which may cause either nuisance or damage to health. ... Audio noise In audio, recording, and broadcast sytems noise refers to the residual low level sound (usually hiss and hum) that is heard in quiet periods of programme. ... Video noise In video and television, noise refers to the random dot pattern that is superimposed on the picture as a result of electronic noise, the snow that is seen with poor (analog) television reception or on VHS tapes. ... Statistical noise is the colloquial term for recognized amounts of variation in a sample. ... Cosmic noise: Random noise that originates outside the Earths atmosphere. ...

• Shot noise in resistors.
• Johnson-Nyquist noise (Thermal noise) in resistors.
• White noise
• 1/f noise (pink noise, or flicker noise)
• Gaussian noise

Gaussian noise

Main article: Gaussian noise

Gaussian noise is noise that has a probability density function (pdf) of the Normal distribution (aka Gaussian distribution). It is most commonly used as additive white noise to yield additive white Gaussian noise (AWGN). Gaussian noise is noise that has a probability density function (pdf) of the Normal distribution (aka Gaussian distribution). ...

Shot noise in resistors

Main article: Shot noise

Shot noise in electronic devices consists of random fluctuations of the electric current in an electrical conductor, which are caused by the fact that the current is carried by discrete charges (electrons). Shot noise is a type of noise that occurs when the finite number of particles that carry energy, such as electrons in an electronic circuit or photons in an optical device, gives rise to detectable statistical fluctuations in a measurement. ... // Electric current is the flow of electric charge. ... In science and engineering, conductors are materials that contain movable charges of electricity. ... Properties The electron is a fundamental subatomic particle that carries a negative electric charge. ...

Johnson-Nyquist noise

Main article: Johnson-Nyquist noise

Johnson-Nyquist noise (sometimes 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). 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). ... In science, and especially in physics and telecommunication, noise is fluctuations in and the addition of external factors to the stream of target information (signal) being received at a detector. ... Look up equilibrium in Wiktionary, the free dictionary. ... // Electric current is the flow of electric charge. ... Electrical conduction is the current (movement of charged particles) through a material in response to an electric field. ... This article may be too technical for most readers to understand. ... Properties The electron is a fundamental subatomic particle that carries a negative electric charge. ...

White noise

Main article: White noise

White noise is a random signal (or process) with a flat power spectral density. In other words, the signal's power spectral density has equal power in any band, at any centre frequency, having a given bandwidth. Four thousandths of a second of white noise White noise ( (help· info)) is a random signal (or process) with a flat power spectral density. ... In applied mathematics and physics, the spectral density is a general concept applied to a signal which may have any physical dimensions or none at all. ...

An infinite-bandwidth white noise signal is purely a theoretical construct. By having power at all frequencies, the total power of such a signal is infinite. In practice, a signal can be "white" with a flat spectrum over a defined frequency band.

Pink, flicker or 1/f noise

Main article: 1/f noise

Pink noise, also known as 1/f noise, is a signal or process with a frequency spectrum such that the power spectral density is proportional to the reciprocal of the frequency. Sometimes pronounced as one over f noise, it is also called flicker noise. In other words, it is a sound that falls off steadily into the higher frequencies, instead of producing all frequencies equally. 1/f noise is a signal or process with a frequency spectrum such that the spectral energy density is proportional to the reciprocal of the frequency. ...

External links

• White noise calculator, thermal noise - Voltage in microvolts, conversion to noise level in dBu and dBV and vice versa