Equivalent noise resistance
In telecommunication, an equivalent noise resistance is a quantitative representation in resistance units of the spectral density of a noise-voltage generator, given by R n = (πW n)/(kT 0), where W n is the spectral density, k is Boltzmann's constant, T 0 is the standard noise temperature (290 K), and kT 0 = 4.00 × 10-21 watt-seconds.Note: The equivalent noise resistance in terms of the mean-square noise-generator voltage, e 2, within a frequency increment, Δf , is given by R n = e 2/(4kT 0Δf ).
Source: from Federal Standard 1037C
