vocoder


Also found in: Dictionary, Acronyms, Wikipedia.

vocoder

[vō′kōd·ər]
(electronics)
A system of electronic apparatus for synthesizing speech according to dynamic specifications derived from an analysis of that speech.

Vocoder

 

a system of telephone communication in which the transmitted signals are not those of speech but rather of a special representation of speech in an encoded form. In this system a sound analyzer at the transmitting end forms coded signals from the speech signals; at the receiving end a synthesizer artificially restores the speech signals from the coded signals. With a vocoder it is possible to achieve a coefficient of syllabic articulation of 83 to 85 percent (this coefficient is between 90 and 91 percent for the ordinary telephone communication). The coding reduces the width of the frequency passband required for the communication channel to 250-350 hertz, as compared with the band from 250 to 3,500 hertz of the ordinary telephone communication, thus increasing the carrying capacity of a long-distance communication line by ten to 13 times.

vocoder

(communications)
Hardware or software which implements a compression algorithm particular to voice.

For example Qualcomm uses a vocoding algorithm to compresses voice data in digital communication systems such as wireless CDMA and Eudora voice attach.

vocoder

(VOice CODER) Same as speech codec.
References in periodicals archive ?
A well-designed vocoder can endure random packet loss of up to 10% with only minor degradation of speech quality.
Other features and functions include two-way Short Messaging Service (SMS) capabilities; simple and mobile IP; AT command interface; dual UARTs; analog audio; two RF connectors; high-speed packet--and circuit-switched data; and support for both 13k QCELP and EVRC vocoders.
A comprehensive suite of vocoders and concurrent support for VoIP over Ethernet and AAL5, as well as VoATM AAL1 and AAL2, highlight the rich feature set and flexibility that system vendors require to migrate to next generation wireline and wireless networks.
This will enable OEMs to download proprietary or commercial-off-the-shelf software for functions such as vocoders, echo cancellers, speech analysis, data and fax modems, encryption, and many others.