A robust Packet Loss recovery scheme for wideband speech codecs

Abstract-In this paper, the use of Source-Controlled Channel Decoding (SCCD) was investigated in estimating parameter values of parametric wideband speech codecs subjected to noise and packet losses. The technique was applied to LP-based and sinusoidal transform-based wideband speech codecs assuming a first order Markov chain to model interframe parameter distribution. Fading and non-fading channels were considered with AWGN using BPSK at the bit level and specified Packet Loss Rates (PLR) at the packet level. An approximation of the 2-state Gilbert model was used in erasing packets. The performance of the scheme was compared to the frame replication scheme of the GSM standard. The scheme gives favorable results in objective and subjective quality measures, and is very robust even at a high PLR of 30%.