Digital Hearing Aid for Sensorineural Hearing Loss : (Ski-Slope Hearing Loss)

Hearing loss, also known as hearing impairment is a partial or total inability to hear. Noise is one of the cause of hearing loss. Hearing aid is an electroacoustic device which is designed to amplify sound. 5.3 percent of earth’s population suffer from hearing loss. The functionality and technical performance of DSP hearing aids are more efficient compared to analog hearing aids. Digital hearing aids are self-adjusting and flexible. In this way, the sound it transmits matches the specific pattern of hearing loss. Adaptive filtering is used which effectively cancels out the additive noise by changing the filter coefficients over time and adapts to the changing signal characteristics according to an optimization algorithm. Gain is selectively added at higher frequency according to the person’s hearing loss profile. This allows for a convenient, detailed control of the frequency response of the hearing aid. Finally the processed signal undergoes power check to assure that the signal power is less than the threshold of pain. A spectrogram which gives a representation of how the frequency content of a signal changes with time is plotted. The MATLAB provides graphics for visualizing data and toolboxes for a wide range of engineering and scientific applications.