High quality 16 kb/s voice transmission
- 24 March 2005
- conference paper
- Published by Institute of Electrical and Electronics Engineers (IEEE)
- Vol. 1, 244-246
- https://doi.org/10.1109/icassp.1976.1170081
Abstract
In this paper, we discuss how adaptive predictive coders employing pitch and coefficient predictors perform when combined with adaptive multilevel quantizers to transmit speech at 16 Kb/s. Performance curves based on fixed point simulations provide a quantitative signal-to-noise analysis as a function of predictor complexity, quantizer adaptation strategy and channel error rate. For example, a fourth order adaptive predictor with pitch loop and adaptive 8-level quantization provides reconstructed speech that is perceptually indistinguishable from the original 2500 Hz band limited input. With channel errors, performance is found to be both a sensitive function of quantizer adaption strategy and predictor complexity. While complex predictors are superior to CVSD at error rates below 10-4, CVSD degrades less rapidly as channel errors increase, At 10-2BER and above, CVSD outperforms the other techniques studied.Keywords
This publication has 3 references indexed in Scilit:
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- Average magnitude difference function pitch extractorIEEE Transactions on Acoustics, Speech, and Signal Processing, 1974
- Digital coding of speech waveforms: PCM, DPCM, and DM quantizersProceedings of the IEEE, 1974