Additive white Gaussian noise

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As additive white Gaussian noise , short AWGN or AWGN (English additive white Gaussian noise ), a channel model called, in which the influence of the channel on the useful signal is modeled by a noise signal of constant spectral noise power density ( white noise ) and gaußverteilter signal amplitude , which is superimposed (added) on the useful signal.

model

In the Telecommunications simple mathematical model of a AWGN channel has gained importance. If a useful signal s (t) is sent through this channel, the signal g (t) at the receiver also contains additive interference n (t) in addition to the useful signal, which represent a realization of a WGR process:

This simple model does not map many real effects of message transmission , such as interference , multipath propagation or dispersion .

Note:

  • white noise is not always Gaussian.
  • The existence of a WGR process cannot be inferred from the Gaussian distribution.

example

Thermal noise in electronic components - for example in a resistor - can be roughly modeled using an additive white Gaussian noise process: In this model, the instantaneous voltage is Gaussian at every point in time, and the voltage at different points in time is completely uncorrelated . Very small noise voltages (in the practical example in the range of nV , µV) occur with a very high probability; however, the probability that noise amplitudes in the range of volts or even kilovolts will occur is very low.

More types of noise

literature

  • Thomas Görne: Sound engineering. Fachbuchverlag Leipzig in Carl Hanser Verlag, Munich et al. 2006, ISBN 3-446-40198-9 .
  • Hubert Henle: The recording studio manual. Practical introduction to professional recording technology. 5th, completely revised edition. Carstensen, Munich 2001, ISBN 3-910098-19-3 .
  • Jens Timmermann: System analysis and optimization of ultra broadband transmission. Scientific Publishing, Karlsruhe 2010, ISBN 978-3-86644-460-7 .
  • Markus Hufschmid: Information and communication. Basics and methods of information transfer, BG Teubner Verlag, Wiesbaden 2006, ISBN 978-3-8351-0122-7 .
  • Robert M. Fano: Information transfer. A statistical theory of communication, R. Oldenbourg Verlag, Munich 1966.
  • Martin Meyer: communication technology. Modern messaging concepts. 2nd Edition. Friedrich Vieweg & Sohn Verlagsgesellschaft, Wiesbaden 2002, ISBN 3-528-13865-3 .
  • Martin Werner: Communication technology. Analog and digital processes with modern applications, 1st edition, Friedrich Vieweg & Sohn Verlag, Wiesbaden 2006, ISBN 3-528-04126-9 .
  • Rudolf Müller: Noise. Second revised and expanded edition, Springer Verlag, Berlin / Heidelberg 1990, ISBN 978-3-540-51145-8 .