EFFECT OF VARIATIONS IN MICROPHONE COVER SHAPE AND WEARING POSITION ON THE PERFORMANCE OF A HEARING-SUPPORT DEVICE MOUNTED ON EAR: SIMULATION STUDY

Morphological and positional factors that can affect the actual performance of the hearing-support (HS) devices are utilized to support the damaged hearing ability of the sensorineural hearing-impaired persons. However, there have been few studies that demonstrated the effects of variations in such design factors on the frequency response of the device experimentally. In this study, the effect of design variations in the shape of the microphone cover on the housing and the wearing position of the device mounted on the ear on the input frequency response of the device and on the performance of an embedded beamforming algorithm were investigated using a human upper body model, a hearing aid housing model, and an acoustic environment model using computer simulation. Experimental results showed that the implemented simulator could simulate the actual acoustic situations (differences less than 5 dB in audible frequency range) and that both of the response patterns of the device and beamforming algorithm were varied in accordance with the variations in the shape of the microphone cover and the mounting position of the device on the ear. These results demonstrate the necessity of additional design and algorithm fine-tuning of each (HS) device to improve its actual speech enhancement performance.