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Receiver system-noise temperature



STEMP = systemp(NF) calculates the effective system-noise temperature, STEMP, in kelvin, based on the noise figure, NF, in decibels. The reference temperature is 290 K.


STEMP = systemp(NF,REFTEMP) specifies the reference temperature.


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Calculate the system noise temperature of a receiver with a 300 K reference temperature and a 5 dB noise figure.

T = systemp(5,300)
T = 948.6833

Input Arguments

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Noise figure in decibels, specified as a nonnegative scalar. The noise figure is the ratio of the actual output noise power in a receiver to the noise power output of an ideal receiver.

Data Types: double

Reference temperature in kelvins, specified as a nonnegative scalar. The output of an ideal receiver has a white noise power spectral density that is approximately the Boltzmann constant times the reference temperature in kelvin.

Data Types: double

Output Arguments

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Effective system-noise temperature in kelvins, returned as a nonnegative scalar. The effective system-noise temperature is REFTEMP*10^(NF/10).


[1] Skolnik, M. Introduction to Radar Systems. New York: McGraw-Hill, 1980.

Extended Capabilities

Version History

Introduced in R2011a