# noisepow

## Syntax

``NPOWER = noisepow(NBW,NF,REFTEMP)``

## Description

example

````NPOWER = noisepow(NBW,NF,REFTEMP)` returns the noise power, `NPOWER`, in watts for a receiver. This receiver has a noise bandwidth `NBW` in hertz, noise figure `NF` in decibels, and reference temperature `REFTEMP` in kelvins.```

## Examples

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Calculate the noise power of a receiver having a noise bandwidth of 10 kHz, a noise figure of 1 dB, and a reference temperature of 300 K.

`npower = noisepow(10e3,1,300)`
```npower = 5.2144e-17 ```

## Input Arguments

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Noise bandwidth of the receiver in hertz, specified as a positive scalar. For a superheterodyne receiver, the noise bandwidth is approximately equal to the bandwidth of the intermediate frequency stages .

Data Types: `double`

Noise figure in decibels, specified as a nonnegative scalar. The noise figure is a dimensionless quantity that indicates how much a receiver deviates from an ideal receiver in terms of internal noise. An ideal receiver only produces the expected thermal noise power for a given noise bandwidth and temperature. A noise figure of 1 (0 dB) indicates that the noise power of a receiver equals the noise power of an ideal receiver. Because an actual receiver cannot exhibit a noise power value less than an ideal receiver, the noise figure is always greater than or equal to 1 (0 dB).

Data Types: `double`

Reference temperature in kelvins, specified as a nonnegative scalar. This argument specifies the temperature of the receiver. Typical values range from 290 to 300 kelvins.

Data Types: `double`

## Output Arguments

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Noise power in watts, returned as a nonnegative scalar. The internal noise power contribution of the receiver to the signal-to-noise ratio.

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