Thermal noise
In
telecommunication,
thermal noise (
Johnson noise) is the
noise generated by thermal agitation of electrons in a conductor. The
noise power,
P , in watts, is given by
P = k
T Δ
f , where k is
Boltzmann's constant in joules per
kelvin,
T is the conductor temperature in kelvins, and Δ
f is the
bandwidth in
hertz.
- Thermal noise power, per hertz, is equal throughout the frequency spectrum, depending only on k and T .
- For the general case, the above definition may be held to apply to charge carriers in any type of conducting medium.
Source: from
Federal Standard 1037C and from
MIL-STD-188
