Chiu K M, Ching P C
Department of Electronic Engineering, Chinese University of Hong Kong, Shatin, N.T.
J Acoust Soc Am. 1996 Apr;99(4 Pt 1):2365-9. doi: 10.1121/1.415424.
The excitation parameters of a multiband excitation model for speech production consist of a pitch period and a series of voiced/unvoiced (v/uv) decisions for a number of fixed frequency bands around the harmonics of the fundamental. In this paper, it is shown that, at most, four v/uv variable-length nonoverlapping frequency bands spanning over the telephone bandwidth are adequate to represent the excitation spectrum that provides an improved modeling of mixed voicing and noisy speech. A quad-band excitation (QBE) method is presented which generates excitation source for a linear prediction vocoder for low bit rate transmission of speech signal and the DRT scores validate the potential of the method.
