Editing Demodulation (section)

{{short description|Process of extracting the original information-bearing signal from a carrier wave}}
{{More citations needed|date=June 2009}}
{{Modulation techniques}}

'''Demodulation''' is the process of extracting the original information-bearing [[signal]] from a [[carrier wave]]. A '''demodulator''' is an [[electronic circuit]] (or [[computer program]] in a [[software-defined radio]]) that is used to recover the information content from the modulated carrier wave.<ref>
{{cite web
|url=http://dictionary.reference.com/browse/Demodulator
|title=Demodulator - Definitions from Dictionary.com
|publisher=dictionary.reference.com
|access-date=2008-05-16
}}
</ref>  There are many types of [[modulation]], and there are many types of demodulators.  The signal output from a demodulator may represent sound (an [[analog signal|analog]] [[audio signal]]), images (an analog [[video signal]]) or [[binary signal|binary]] data (a [[Digital signal (electronics)|digital signal]]).

These terms are traditionally used in connection with [[radio receiver]]s, but many other systems use many kinds of demodulators. For example, in a [[modem]], which is a contraction of the terms [[modulator]]/demodulator, a demodulator is used to extract a serial digital data stream from a [[carrier signal]] which is used to carry it through a [[telephone line]], [[coaxial cable]], or [[optical fiber]].