A comparison of adaptive differential pulse code mod- ulation (ADPCM) speech compression systems is made using different recursive adaptive linear prediction algorithms. The particular algorithms considered are 1) a fixed predictor, 2) the adaptive least mean square (LMS) transversal predictor, 3) the LMS (gradient) lattice predictor, 4) the least squares (LS) lattice predictor, and 5) an LS lattice predictor combined with a third-order pitch inverse filter. The last configuration uses the pitch detection scheme described in  to recursively estimate the pitch period in the context of an adaptive predictive coder (APC). The results indicate that for the conditions simulated, the difference in system performance using the different adaptive algorithms is negligible, suggesting that the predictor having the simplest implementation is the best.
ASJC Scopus subject areas
- Electrical and Electronic Engineering