<communications> Any part of a signal that is not the true or original signal but is introduced by the communication mechanism.
A common example would be an electrical signal travelling down a wire to which noise is added by inductive and capacitive coupling with other nearby signals (this kind of noise is known as "crosstalk").
A less obvious form of noise is quantisation noise, such as the error between the true colour of a point in a scene in the real world and its representation as a pixel in a digital image.
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Nearby terms: Nodal Switching System « noddy « node « noise » noise margin » noise shaping » NOL