The Enhanced Variable Rate Codec (IS-127) is defined in TIA-EIA-IS-127 and in 3GPP2 for use in wideband spread spectrum (CDMA) systems.

EVRC communicates at channel rates corresponding to 9600, 4800 and 1200 bps frame rates. The speech coder source bit rates corresponding to these channel rates are full rate (8.5 kbps), half rate (4 kbps), and eighth rate (800 bps). EVRC operates at these different bit rates depending on the source signal. The lowest rate is for background noise. Because EVRC is a source-controlled codec, its average bit rate varies, but it typically operates at around 6 kbps.

Widely used for cellular telephony in CDMA networks, it also has applications in VoIP.

For licensing IPR, please contact licensing@voiceage.com.