SYNTHESIS OF VOICED SOUNDS FROM A 2-MASS MODEL OF VOCAL CORDS
SYNTHESIS OF VOICED SOUNDS FROM A 2-MASS MODEL OF VOCAL CORDS
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DOI：
10.1002/j.1538-7305.1972.tb02651.x
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发表时间：
1972-01-01
影响因子：
--
通讯作者：
FLANAGAN, JL
中科院分区：
文献类型：
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作者：
ISHIZAKA, K;FLANAGAN, JL
浊音生成的模型，其中计算人类声带和声道的详细声学行为。声带近似由两个刚度耦合质量组成的自振源。声道被表示为双边传输线。通过声带的一维伯努利流和声道中的平面波传播用于建立在有声语音生成中占主导地位的声学因素。推导出连续系统的差分方程描述，并在DDP-516计算机上编程进行交互式研究。计算采样波形：通过声带开口（声门）的声学体积速度;声门面积;和口输出声压。还确定了基本语音频率、声门下（肺）压力、声带张力、声门面积和声带振动占空比之间的函数关系。结果表明，双质量模型复制了人类声带行为的主要特征。基频随声门下压的变化范围为2 ~ 3 Hz/cm H2O，基本上与程序化声道中元音的结构无关。声道本征频率与声门容积流量之间的相互作用很强。脐带边缘运动的相位差在0至60度的范围内，并且脐带张力的控制导致类似于人类的胸部/假声状况的行为。发声中性，或声带开口的休息区，被证明是建立自振荡的关键因素。最后，完整的合成系统提出了语音信号的有效的生理描述，即声门下压力、声带张力、声带开口的剩余面积和声道形状。
A model of voiced‐sound generation is derived in which the detailed acoustic behavior of the human vocal cords and the vocal tract is computed. The vocal cords are approximated by a self‐oscillating source composed of two stiffness‐coupled masses. The vocal tract is represented as a bilateral transmission line. One‐dimensional Bernoulli flow through the vocal cords and plane‐wave propagation in the tract are used to establish acoustic factors dominant in the generation of voiced speech. A difference‐equation description of the continuous system is derived, and the cord‐tract system is programmed for interactive study on a DDP‐516 computer. Sampled waveforms are calculated for: acoustic volume velocity through the cord opening (glottis); glottal area; and mouth‐output sound pressure. Functional relations between fundamental voice frequency, subglottal (lung) pressure, cord tension, glottal area, and duty ratio of cord vibration are also determined.Results show that the two‐mass model duplicates principal features of cord behavior in the human. The variation of fundamental frequency with subglottal pressure is found to be 2 to 3 Hz/cm H2O,and is essentially independent of vowel configuration in the programmed tract. Acoustic interaction between tract eigenfrequencies and glottal volume flow is strong. Phase difference in motion of the cord edges is in the range of 0 to 60 degrees, and control of cord tension leads to behavior analogous to chest/falsetto conditions in the human. Phonation‐neutral, or rest area of cord opening, is shown to be a critical factor in establishing self‐oscillation. Finally, the complete synthesis system suggests an efficient, physiological description of the speech signal, namely, in terms of subglottal pressure, cord tension, rest area of cord opening, and vocal‐tract shape.