An Improved Algorithm for Noise Reduction in Hearing Aids

Abstract

The noise reduction algorithm is a vital algorithm in hearing aids. To improve performances, an improved algorithm is proposed. For the basic perception filter, the masking tone will be audible after filtering. To solve this problem, one weighted perception filter algorithm for the simulation of the auditory mechanism is designed. Based on the basic perception filter, the priori SNR is firstly estimated by the direct decision method and then revised by the optimal smoothing factor method. The optimal value is obtained based on minimum mean square error criterion, and the gain of weighted perception filter is computed. Experiment results show that the proposed method can effectively eliminate the residual noise, reduce the interference, and improve the speech comprehension of hearing-impaired patients under the noisy environment.