Design of Biquad Filter in Digital Hearing Aid

in recent years, due to the increase of hearing impairment patients, the demand for hearing aids in the market is also increasing, which put forward higher requirements for the quality and effect of hearing-aids. However, many hearing-aids cannot achieve the ideal sound processing effect because of the imperfect audio processing system, which greatly reduces the user experience. Aiming at this problem, this paper presents a method to optimize a hearing-aid system mainly by using biquad filter. In this hearing aid system, the front and back of the digital audio processing module are respectively added with the front high pass IIR filter and the post low pass IIR filter. We can adjust the filter cutoff frequency to filter out unwanted audio interference and noise, which will not only optimize signal, but also further improve the flexibility of the audio processing system. In this paper, according to the result of Matlab simulation and analysis of the system, the system can improve the hearing aid experience to a certain extent.