One-dimensional static vocal tract model in the time domain

Acoustical science and technology

article

Hironori Takemoto¹  Seiji Adachi²  Natsuki Toda¹ 

[1] Chiba Institute of Technology;Tezukayama University

关键词: Vocal tract model;    FDTD;    Wall vibration;    Vowel production;    Time domain;   

DOI  :  10.1250/ast.44.9

学科分类：声学和超声波

来源: Acoustical Society of Japan

【 摘 要 】

The vocal tract can be modeled as an acoustic tube in the low-frequency region because the plane wave propagation is dominant. Further, it can be considered static for a limited short period during running speech, such as vowels. Thus, its acoustic properties have been examined mainly using the transmission line model (TLM), that is, the one-dimensional static model in the frequency domain. In the present paper, we propose a one-dimensional static model in the time domain based on the finite-difference time-domain method. In this model, the vocal tract is represented by the cascaded acoustic tubes of different cross-sectional areas. The pressure and wall vibration effects are simulated at the center of each tube. On the other hand, the volume velocity is calculated at the labial end. According to the leapfrog algorithm, the pressure and volume velocity are sequentially computed. As a result, the impulse responses of the vocal tracts for the five Japanese vowels were calculated, and the corresponding transfer functions agreed well with those calculated by the TLM in the low-frequency region. The mean absolute percentage difference of the lower four peaks for the five vowels was 2.3%.

【 授权许可】

Unknown