Bandwidth extension of narrow band speech using cepstral linear prediction

In this paper we propose a new post processing technique to recover the missing high band frequency components lost during low pass filtering in band-limited narrow band speech signals. The approach taken is based on linear prediction of cepstral coefficients from narrow band speech and an excitation function to estimate the high band spectral envelope of the original wideband speech signal. The method presented here improves both subjective and objective quality of bandlimited speech at the receiver side of a communication system.