Noise (electronics)

random fluctuation in an electrical signal

In electronics, noise is a random fluctuation in an electrical signal. This happens in all electronic circuits.[1] Noise made by electronic devices varies greatly. In communication systems, noise is an error or random disturbance of useful information in a communication channel.

Analog display of random fluctuations in voltage

The noise is the total of unwanted or disturbing energy from natural and sometimes man-made sources. Noise is usually distinguished from interference, such as deliberate jamming or other unwanted electromagnetic interference.

If a message is transmitted in a natural language (a series of letters which make sense), then it is more resistant to noise than a spoken language.


  1. Motchenbacher C.D. & Connelly J.A. (1993). Low-noise electronic system design. Wiley Interscience.