A novel vocoder concept based on discrete time acoustic tubes

A novel vocoder concept is presented which is based on discrete time equivalents of the uniform acoustic tube. Models of lossy sections of different lengths are cascaded to represent the vocal tract. Results comparable to a standard 12-section LPC-vocoder are achieved cascading typically 5 tube sections of different lengths. Major savings are derived in terms of the hardware complexity during speech synthesis and in terms of the data rate during speech transmission. The concept can also be used for modeling the nasal tract by interconnecting a discrete time acoustic tube system to the vocal tract model via a proper adaptor.