A new error concealment method for consecutive frame loss based on CELP speech

Lower bit-rate speech coding by digital signal processing becomes more and more important with the development of communication technology. Speech codec should keep good quality in various conditions such as diverse channel, different speakers and background noises. When transmission environment is poor and the channel coding could not effectively control error occurrences, error concealment will be applied. Generally speaking, error concealment is based on extrapolation method or repetition method in which the speech coding parameters are extrapolated or repeated from the parameters of the surrounding good frame received. This paper focuses on speech coding standard Adaptive Multi-Rate (AMR) and two points are discussed: the value of pitch lag when consecutive frames are lost and the recovery of codebook gain for good frames after continuous bad frames. Objective and subjective experimental results confirm that the proposed algorithm could achieve better speech quality.