Abstract
According to antisymmetry of basilar membrane (BM) movements, a new mathematical model of cochlea is derived using viscous cochlear fluid theory, and then transformed into a digital cochlear model with bilinear transformation. The frequency responses are found to be quite consistent with the experimental data, especially the high frequency slope is much more improved. A new cochlear map and 3 dB bandwidth characteristics for cochlear filter banks are obtained and presented, which will make applications of 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 easily in speech processing system.
Highlights
As a central part of auditory system, cochlea acts electrically as a highly overlapped bandpass filter bank
H.B.Allen, et al [1,2] used Green's function method to find a fluid pressure with assumption of inviscous cochlear fluid and acquired a two-dimensional cochlear model represented by an integration equation
Cochlear characteristics can be influenced by many factors, but basilar membrane (BM) vibration and cochlear fluid motion should be two main factors
Summary
As a central part of auditory system, cochlea acts electrically as a highly overlapped bandpass filter bank. The amplitude frequency response is not very satisfied, especially low frequency slope is not as sharp as desired, structure of the model appears complicated either. Cochlear characteristics can be influenced by many factors, but BM vibration and cochlear fluid motion should be two main factors. Much work was focused on BM properties, such as nonlinearity and activity of BM vibration [3,4,5], but cochlear fluid properties were paid little attention. A two-dimensional mathematical model of cochlear with viscous fluid motion was developed in [7,8], but high frequency slope of model's amplitude frequency response is not as sharp as desired, the time variable was not discretized either. Based on our previous results, a new mathematical model of cochlea is developed and transformed into a digital form using bilinear transformation. The cochlear map which relates the center frequency of cochlear filters with BM locations are acquired and presented in a mathematical formula, and 3 dB bandwidth characteristics which relate the 3 dB bandwidth of cochlear filters with BM locations are formulated
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
