Search results
Results from the WOW.Com Content Network
Grey noise spectrum The result is that grey noise contains all frequencies with equal loudness , as opposed to white noise , which contains all frequencies with equal energy . The difference between the two is the result of psychoacoustics , more specifically the fact that the human hearing is more sensitive to some frequencies than others.
Noise that has a frequency spectrum of predominantly zero power level over all frequencies except for a few narrow bands or spikes. Note: An example of black noise in a facsimile transmission system is the spectrum that might be obtained when scanning a black area in which there are a few random white spots. Thus, in the time domain, a few ...
A long list of noise measures have been defined to measure noise in signal processing: in absolute terms, relative to some standard noise level, or relative to the desired signal level. They include: Dynamic range, often defined by inherent noise level; Signal-to-noise ratio (SNR), ratio of noise power to signal power
In technology, noise is unwanted signals in a device or apparatus, commonly of an electrical nature. The nature of noise is much studied in mathematics and is a prominent topic in statistics . This article provides a survey of specific topics linked to their primary articles.
Different types of noise are generated by different devices and different processes. Thermal noise is unavoidable at non-zero temperature (see fluctuation-dissipation theorem), while other types depend mostly on device type (such as shot noise, [1] [3] which needs a steep potential barrier) or manufacturing quality and semiconductor defects, such as conductance fluctuations, including 1/f noise.
Noise reduction is the process of removing noise from a signal. Noise reduction techniques exist for audio and images. Noise reduction algorithms may distort the signal to some degree. Noise rejection is the ability of a circuit to isolate an undesired signal component from the desired signal component, as with common-mode rejection ratio.
In telecommunications and computer networking, communication channels can be affected by wideband Gaussian noise coming from many natural sources, such as the thermal vibrations of atoms in conductors (referred to as thermal noise or Johnson–Nyquist noise), shot noise, black-body radiation from the earth and other warm objects, and from ...
Internet background noise has been used to detect significant changes in Internet traffic and connectivity during the 2011 political unrest from IP address blocks that were geolocated to Libya. [ 5 ] Backscatter is a term coined by Vern Paxson to describe Internet background noise resulting from a DDoS attack using multiple spoofed addresses. [ 6 ]