Research on hoarse speech based on vocal cord model and glottal waveform

Considering the faCt that hoarse speech is usually caused by pathological changes of vocal cords whose motion state is reflected by glottal waveform,this paper presents a method of research on hoarse speech based on dissymmetric four-mass model of vocal cords and glottal wave analysis-synthesis.By linking hoarse speech waveform with glottal wave and the vocal cord model,the characteristic parameters of normal speech and hoarse speech before and after laryngeal operation are studied.The parameters of glottal wave periodicity and vocal cord symmetry of hoarse speeChes are compared with those of normal speech.It is applied to analyzing the relations between model parameters and hoarse mechanism in pathology and physiology.Experimental results show that the new method of research can unveil the relations between acoustic features and pathological causes of hoarse speech and thus provides theoretical and experimental bases for non-contact diagnoses of laryngeal diseases and for improving the tone quality of hoarse speech.