一种二阶差分式耳蜗模型

A Second-Order Difference Cochlear Model

本文通过双线性变换将一连续时间、连续空间耳蜗模型变换成一离散时间、离散空间耳蜗模型，并获得了一种实用的二阶差分式耳蜗模型．与传统耳蜗模型相比，新模型的幅频特性与相频特性更加接近耳蜗实际特性，尤其是幅频特性下降沿得到了较大改善，另外，文章从理论上推出了耳蜗图，并求出了耳蜗滤波器的３ｄＢ带宽特性，该模型具有简单的数学结构和较好的频率特性，相信其在语音信号处理中的应用会变得更加实际．

A mathematical model of cochlea is transformed into a applicable second-order difference cochlear model with bilinear transformation.Compared with the traditional cohlear model,the frequency response of new model are found to be quite consistent with the experimental data,especially the high frequency slope is much more improved.A new cochlear map and 3dB bandwidth characteristics for cochlear filter banks are obtained and presented,which will make applications of the cochlear model more quantitative and accurate.Due to simplicity of its structure and reality of its characteristics,it will be proved the model can be used effectively in speech processing system.