excess noise ratio (ENR)

The excess noise ratio(ENR) is a temperature-dependent noise ratio. It is defined as the noise generated above 290 Kelvin (K), i.e. above room temperature. This forms the standard noise temperature.

Typically, the ENR value, which is expressed in decibels( dB) and calculated from the logarithm of the temperature difference, is plotted as a graph of temperature in Kelvin versus frequency.