EFFECTIVE PARAMETER FOR RECOGNIZING VOWEL IN CHINESE SPEECH - VOCAL TRACT LENGTH.

This paper is based on the similarity of the anatomical structures of the vocal organs among adults and the regularity of vocal tract length. The purpose is to distinguish between different vowels in Chinese speech. We have discovered that vocal tract lengths of spoken vowels a, o, u, i, e have fixed length rates and their absolute lengths are quite certain. Therefore this characteristic is useful for automatic identification of speech sounds produced by arbitrary speakers. The vocal tract length is not directly available from the speech signal. A hypothesis which uses the fourth or the fifth formant frequency to determine the vocal tract length is proposed. There is very good agreement between our experimental length parameter and Fant's reference value.