Abstract
While the frequency domain equivalent models were seldom utilized and discussed, previous computer models to simulate human auditory mechanism were mainly constructed in the time domain. With a higher computational complexity, the time domain models usually match the real mechanism well, for they require solving a set of partial differential equations for each time step. The frequency domain models, on the other hand, offer faster simulation results through transfer functions. However, due to the nonlinearity of the cochlea, the amplification mechanism cannot be described with simple linear relationships, and the results from the frequency domain models could deviate from the real mechanism. Based on the frequency model of the inner ear (Liu and Neely, 2009), this study improves the existing model by introducing the effective sensitivity of the cochlea, which could be approximated by the quasi-linear method. The frequency domain model with nonlinearity is established through this approach, providing more precise simulation results with high efficiency. The improved frequency model is capable of simulating different cochlear characteristics, including the displacement and phase of Reticular Lamina, the sensitivity ratio, and the wave number per length. Comparing with the simulation results from the previous time domain model(Liu and Neely, 2010), the improved frequency domain model in this study provides compatible results and a efficient solution to the simulation of human auditory mechanism.