Comfort noise ( engl. Comfort noise ) is in the context of digital signal processing, artificially generated noise , which is used in the digital transmission of human speech for filling speech pauses.
Applications can be found wherever voice signals are digitally compressed using audio codecs . Examples are digital mobile communications such as GSM and IP telephony . Comfort noise is always used in conjunction with a squelch , which suppresses all noise below a certain volume level on the speaker's side.
Comfort noise creates the illusion of a continued connection for the listener during pauses in speech, without using the data transmission rate in the network that is otherwise necessary for the transmission of the noise . Without comfort noise, complete silence would occur during pauses in conversation, which is usually disruptive to the listener. The sudden silence gives the impression that the voice connection has been broken.
- Dr. Egmont Foth: IP Telephony Manual. FOSSIL-Verlag, Cologne 2001, p. 17.
- Jochen Nölle: Voice over IP basics, protocols, migration. 2nd edition, VDE Verlag, Berlin 2005, p. 44.