[Study of three-dimensional speech chart by time-frequency analysis in Chinese Mandarin Monosyllabic word phonemes].

OBJECTIVE: To investigate the physical characteristic of Chinese Mandarin Monosyllabic word phonemes by the time-frequency analysis. METHODS: Manufactured and study the three-dimensional speech chart which was on the basic of information of the time-frequency analysis in 40 monosyllabic words with the SigmaPlot 9.0 and Matlab 7.0 software. RESULTS: The mean value of basic frequency in 40 monosyllabic words was between 220 to 320 Hz area, and the mean value of four groups has significant difference by t-test. It is indicated by time-frequency analysis that the characteristics vary according to the tone of monosyllabic words. With the change of time, the various frequencies and its intensity of tone first remain basically unchanged, the curve is horizontal type; the different frequencies of tone second gradually tend to high-frequency direction, the graph is upward-type, additionally, the intensity of some tone drops little; the divers frequencies of tone third firstly deflect to low-frequency areas, then increasingly deviate to high-frequency direction of bias after maintaining a period of time, the figure is v-type, intensity changes are concave-shaped; The various frequencies of tone fourth deviate from high-frequency to low-frequency areas, and its intensity drops sharply, the graph is decreased type. CONCLUSION: Through time-frequency analysis and three-dimensional speech chart observation, we consider that the physical characteristic of Chinese Mandarin Monosyllabic word phonemes mainly reflects the frequencies and intensity change with time.