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Area Oscillations, signals and related devices / Noise and interference

IEV ref702-08-59

Symbol
F ¯ MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbbjxAHXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaeqabiGaciGacaqadmaadaqaaqaaaOqaaiqadAeagaqeaaaa@3630@

en
(mean) noise factor (of a linear two-port device)
(mean) noise figure (of a linear two-port device)
the ratio of the total noise power appearing at the output of a given linear two port device within a specified frequency band, to the portion of this power originating from the one-port device connected to the input of the two port device, the noise temperature of the one-port device being assumed equal at all frequencies to the reference thermodynamic temperature conventionally fixed around 290 K

Note 1 – The mean noise factor F ¯ MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbbjxAHXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaeqabiGaciGacaqadmaadaqaaqaaaOqaaiqadAeagaqeaaaa@3630@ is related to the mean noise temperature T as follows:

F ¯ =1+ T ¯ T 0 MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbbjxAHXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaeqabiGaciGacaqadmaadaqaaqaaaOqaaiqadAeagaqeaiabg2da9iaaigdacqGHRaWkdaWcaaqaaiqadsfagaqeaaqaaiaadsfadaWgaaWcbaGaaGimaaqabaaaaaaa@3B93@

where T0 is the reference thermodynamic temperature.

Note 2 – The value of the mean noise factor may be expressed in decibels. 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.


fr
facteur de bruit (moyen) (d'un biporte linéaire) m
rapport de la puissance totale du bruit apparaissant à la sortie d'un biporte linéaire donné dans une bande de Fréquences spécifiée à la partie de cette puissance qui provient du monoporte connecté à l'entrée du biporte, la température de bruit du monoporte étant supposée égale, à toute fréquence, à la température thermodynamique de référence fixée conventionnellement au voisinage de 290 K

Note 1 – Le facteur de bruit moyen F ¯ MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbbjxAHXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaeqabiGaciGacaqadmaadaqaaqaaaOqaaiqadAeagaqeaaaa@3630@ d'un biporte est relié à sa température moyenne de bruit T par la relation:

F ¯ =1+ T ¯ T 0 MathType@MTEF@5@5@+=feaagCart1ev2aqatCvAUfeBSjuyZL2yd9gzLbvyNv2CaerbuLwBLnhiov2DGi1BTfMBaeXatLxBI9gBaerbbjxAHXgarqqtubsr4rNCHbGeaGqipG0dh9qqWrVepG0dbbL8F4rqqrVepeea0xe9LqFf0xc9q8qqaqFn0lXdHiVcFbIOFHK8Feea0dXdar=Jb9hs0dXdHuk9fr=xfr=xfrpeWZqaaeqabiGaciGacaqadmaadaqaaqaaaOqaaiqadAeagaqeaiabg2da9iaaigdacqGHRaWkdaWcaaqaaiqadsfagaqeaaqaaiaadsfadaWgaaWcbaGaaGimaaqabaaaaaaa@3B93@

T0 est la température thermodynamique de référence.

Note 2 – Le facteur de bruit moyen peut s'exprimer en décibels. En anglais, on emploie généralement "noise factor" pour désigner un facteur de bruit exprimé sous forme arithmétique, et "noise figure" lorsqu'il est exprimé en décibels.


ar
متوسط عامل الضوضاء

de
mittlerer Rauschfaktor (eines linearen Zweitors), m

es
factor de ruido (medio) (de un dispositivo bipuerta lineal)

it
cifra di rumore (medio) (di un elemento lineare a due porte)

ko
평균 잡음 지수, <선형 2-단자쌍 장치>

ja
平均雑音指数, <線形二端子対デバイスの>
雑音指数, <線形二端子対デバイスの>

pl
współczynnik szumu średni (czwórnika liniowego)

pt
factor médio de ruído (de um biporto linear)

Publication date: 1992-03
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