听觉部位学说与频率差阈

On the place theory and the frequency difference limen of hearing

长时间以来一直认为听觉的部位学说,是无法解释频率差阈这样高达0．3％的频率分辨能力的。因而有时间学说和模式识别方法来加以说明。本文提出一种部位相关模型——邻带差值法,在部位学说和心理物理调谐曲线实验数据的基础上, 利用听觉滤波器相邻通带之间的能量分配关系,完全可以达到千分之几的纯音频率分辨能力。文中用一个标准的1/3倍频程滤波器为例,实验证明了它的可能性。这一模型也可用于语音信号的基频提取和纯音频率的精密测量。

It has been a barrier that the place code is fax too coarse a mechanism to account for the finest frequency difference limen for place theory of hearing since which was proposed in 19th century. A place correlation model, which takes the energy distribution of a pure tone in neighboring bands of hearing filters into full account, was put forward in this paper. The model based on the place theory and some experimental results on the psychophysical tuning curves of hearing can explain the finest difference limen for frequency （about 0.3% at 1000 Hz） easily. Using a standard 1/3 octave filter bank the relationship between the frequency of a input pure tone apart from a center frequency of Kth filter band, A f, and the output intensity difference of Kth and （K ＋ 1）th filters, △E, was established in order to show the fine frequency detection capability of the filter bank. This model can also be used to abstract the fundamental frequency of speech and to measure the frequency of pure tone precisely.