Minimize Frequency Overlapping of Auditory Signals using Complementary Comb Filters

Abstract

Cochlear hearing impairment causes overlapping of auditory speech signals having close frequency contents. Such impairment arises due to the hardening of hearing cells that effects the frequency-splitting ability of inner ear. Person with such disabilities are unable to distinguish between speech signals with high-frequency correlation. This work proposes an implementation of complementary feedforward comb filters to reduce the overlapping of auditory signals. In auditory frequency overlapping, a lower frequency loses their identities due to presence of higher frequencies. Here, two complementary comb filters have been designed to match alternate critical bandwidths of audio signals. Results shown that presenting these alternate frequency bands to human ear in the even-odd index significantly minimizes the frequency overlapping and thereby improves audibility in the hearing impaired.