Modeling speech production using finite difference techniques

Because of limitations in computing resources and analysis methods, speech processing techniques have relied on linear models that make simplifying assumptions about the manner of propagation, losses, and the geometry of the vocal tract. This research has developed a new, more sophisticated model of speech production that is based on numerical simulation of wave propagation in the vocal tract. The model uses a numerical analysis technique, finite differencing, to solve for wave propagation in a complicated geometry that is more representative of the vocal tract than previous models. The objective in developing this model of speech production is to enable the researcher to investigate and compare theories of speech production of varying complexity. The model is designed as a research tool in which it is possible to vary the driving equations and boundary conditions as well as the vocal tract geometry and the excitation to the vocal tract. Simulations that compare the speech produced given several different glottal models in a fixed geometry have been conducted. The model has also been used to study speech produced in several geometric configurations representing several different vowels. [Work supported by NSF Grant No. CDA9211129.]