In electronics,
noise temperature is one way of expressing the level of available noise power introduced by a component or source. The
power spectral density of the noise is expressed in terms of the temperature (in
kelvins) that would produce that level of
Johnson–Nyquist noise, thus:
![](http://info.babylon.com/onlinebox.cgi?rt=GetFile&uri=!!ARV6FUJ2JP&type=0&index=1985)
where:
is the power (in watts)
is the total bandwidth (Hz) over which that noise power is measured
is the Boltzmann constant (1.381×10-23 J/K, joules per kelvin)
is the noise temperature (K)