IEVref: 702-08-57 ID: Language: en Status: Standard Term: spot noise factor, Synonym1: spot noise figure, [Preferred] Synonym2: Synonym3: Symbol: F(f) Definition: ratio of the available power spectral density of the noise appearing at a given frequency at the output of a given linear two-port device, to the spectral density which would be present at the output if the only source of noise were the thermal noise due to a one-port device connected to the input and which is assumed to have at all frequencies a spot noise temperature equal to the reference thermodynamic temperature fixed by convention at around 290 KNote 1 to entry: The spot noise factor F(f) of a linear two-port device is related to the equivalent spot noise temperature T(f) as follows: $F\left(f\right)=1+\frac{T\left(f\right)}{{T}_{0}}$where T0 is the thermodynamic reference temperature. Note 2 to entry: In English, the term “noise factor” is generally employed when the ratio is expressed arithmetically, and “noise figure” is employed when the ratio is expressed in decibels. Publication date: 2018-09 Source: Replaces: 702-08-57:1992-03 Internal notes: CO remarks: TC/SC remarks: VT remarks: Domain1: Domain2: Domain3: Domain4: Domain5: