Algorithm Research And DSP Implementation For Digital Hearing Aids Based On Auditory Masking

Deafness has become a global problem, the best solution for deafness means to wear hearing aids, voice through hearing aids for reduce noise, improve human ear on the voice level of comfort. Traditional analog hearing aids, only to strengthen the human ear to the voice of perception, this simple amplification can help the patients of conduction hearing loss. But the accounting for the majority of deaf patients with SNHL in patients with virtually no benefits, it will increase the ear to feel much bad. Solving the nerve deafness in patients with hearing loss, the most critical issue is to change the distribution of audio, let patients with limited hearing to feel the voice, and the core processors of digital hearing aids can add voice algorithm, and change the distribution of voice, the birth of digital hearing aids to deaf patients is a good news.This paper focuses on the digital hearing aids of auditory masking. We use ear to the physiological characteristics-auditory masking effect of the digital hearing aids to the core algorithm, directly from the ear to the hearing of the physical to have an improvement of the human ear to the voice of comfort.This paper firstly introduces the three core algorithm for digital hearing aids, on their strengths and weaknesses. We use the speech enhancement algorithms of masking effect to the digital hearing aids. This has the advantage of directly from the people to the character- ristics of the ears, ears of the people voice perception that the maximum comfort.Auditory masking effect for voice enhancement algorithms, the paper of the original algorithm in the auditory masking threshold value is not accurate, resulting spectrum by coefficient calculation error; voice distortion caused too great a problem, an improved method of calculation. In the original spectrum by joining the formula for calculating the coefficient of revised parameters, the algorithm can reduce the voice distortion. Simulation results show that the algorithm can improve the voice signal to noise ratio also improved voice quality.Then, the traditional wide dynamic compression algorithm, in the realization of the gain spectrum ignoring the voice formant, after the spectrum gain resonance from the peak of the non-linear changes, change the resonance frequency of the peak.For this issue, we bring forward a new WDRC algorithm which is based on the estimated formant, reduce the resonance peak of nonlinear distortion and improved the auditory comfort.Finally, the three core algorithm of the digital hearing aids were verified .The using of the SEED-DEC5416 development board has heard several figures for the algorithm to make a prototype of the digital hearing aids. Practice shows that the module to meet the real-time voice and reach of digital hearing aids voice processing results.