An Improvement of G.711 PLC Using Sinusoidal model
Kazuyuki Nakamura, Keiichi Funaki · 2005
As broadband IP network is commonly used in home and office the demand of IP telephone is increasing more and more. On IP telephone packet loss occurs, as a result, speech quality is degraded seriously. Hence, packet loss concealment (PLC) is required in IP telephone. G.711 appendix I PLC algorithm has been recommended by ITU-T in 1999 and it is widely used in IP telephone. The performance of the G.711 PLC scheme is not sufficient, thus, we have already developed the improved algorithm using LPC analysis and synthesis scheme. In the improved method past speech is divided into LPC parameters and residual signal and lost residual signal is recovered by the G.711 PLC scheme and lost speech signal is recovered by synthesizing with the repeated LPC parameters and recovered residual signal. In this paper sinusoidal model is introduced to predict the lost residual signal more accurately. The estimation and prediction performance are evaluated by objective measure and the prediction is embedded in the improved G. 711 PLC method.