Calculation of vocal tract length

There are many different vocal tract shapes which could produce the same speech signal. One of the parameters of the vocal tract which is not directly available from the speech signal is the length of the tract. A hypothesis is proposed for determining the vocal tract length from a specification of the impedance seen at the lips. Vowel data of Fant [3] are used to test the hypothesis. There is very good agreement between the experimental and predicted values of this length parameter.