Analog signal

From ArticleWorld

A variable signal which is continuous in time as well as amplitude is referred to as an analog signal. This term is used in not just the electrical context; pneumatic and hydraulic systems also involve this concept.


Information which is conveyed by an analog signal is a measured response to changes in phenomena such as light, sound, temperature and pressure. The measurement is achieved by means of a transducer, whose task is to produce electrical equivalents of the above mentioned physical quantities. The signals created may be in the form of current or voltage variations.

An example of a transducer at work is a microphone, which is used in sound recording. The variation in levels of pressure of sound reaching the microphone causes a corresponding change in the voltage amplitude of current present in it. This is how a nominally continuous electrical signal that matches with another physical signal impressed on a transducer is obtained.

Analog signaling drawback

The main drawback of analog signaling is the inclusion of noise. Noise refers to random distortions that gain dominance as distances and complexities involved increase.