Noise power
In telecommunications, the term noise power has the following meanings:
- The measured total noise in a given bandwidth at the input or output of a device when the signal is not present; the integral of noise spectral density over the bandwidth
- The power generated by a random electromagnetic process.
- Interfering and unwanted power in an electrical device or system.
- In the acceptance testing of radio transmitters, the mean power supplied to the antenna transmission line by a radio transmitter when loaded with noise having a Gaussian amplitude-vs.-frequency distribution.
Noise power can be calculated by multiplying the noise spectral density with the signal bandwidth <math display=block>N_\text{p} = k_\text{B}TB,</math> where:
- Template:Math is the Boltzmann constant ≈ Template:Physconst
- Template:Mvar is the absolute temperature of the device; and
- Template:Mvar is the bandwidth.