Equivalent noise resistance
In telecommunications, an equivalent noise resistance is a quantitative representation in resistance units of the spectral density of a noise-voltage generator, given by Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle R_n = \frac {\pi W_n}{k T_0} } where Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle W_n} is the spectral density, Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle k} is the Boltzmann constant, Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle T_0} is the standard noise temperature (290 K), so Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle kT_0 = 4.00 \times 10^{-21}\,[Ws]} .
Note: The equivalent noise resistance in terms of the mean-square noise-generator voltage, e2, within a frequency increment, Δ f, is given by
- Failed to parse (SVG (MathML can be enabled via browser plugin): Invalid response ("Math extension cannot connect to Restbase.") from server "https://wikimedia.org/api/rest_v1/":): {\displaystyle R_n = \frac{e^2}{4 k T_0\,\Delta f}.}
Public Domain This article incorporates public domain material from the General Services Administration document: "Federal Standard 1037C".
