Variable rate speech coding for multiple access wireless networks

Variable-rate speech coding is a key component of certain multiple access schemes for wireless networks. Such coding methods exploit the silent intervals in a conversation and the statistical variability of active speech, to enhance network capacity for a given speech quality. Voice activity detection schemes distinguish active speech from background noise. Variable-rate coding algorithms are based on source or network control of rate. A source-controlled variable-rate speech coding algorithm, named variable rate phonetic segmentation (VRPS), is described. In VRPS the rate and coding strategy are based on phonetic classification of speech segments