Inner product based-multiband vector quantization for wideband speech coding at 16kbps

This paper describes a multiband vector quantization (VQ) technique for wideband speech coding at 16 kb/s. Our approach consists of splitting the input speech into two separate bands and then applying an independent coding scheme for each band. A code excited linear prediction (CELP) coder is used in the lower band while a transform based coding strategy is applied in the higher band. The spectral components in the higher frequency band are represented by a set of modulated lapped transform (MLT) coefficients. The higher frequency band is divided into three subbands, and the MLT coefficients construct a vector for each subband. For the vector quantization (VQ) of these vectors, an inner product-based distance measure is proposed.