Audio signal's test in designing a cost-effective hearing aid device using a microcontroller. (2016)

• Record Type: Journal Article
• Authors: Rehman, Muhammad Zia ur; Shah, Syed Irtiza Ali; Javaid, Muzzamil; Gilani, Syed Omer; Ansari, Umar
• Is Part Of: International journal of biomedical engineering and technology. Volume 20:Number 3(2016)
• Page Start: 195
• Page End: 207
• Publication Date: 2016
• Subjects: audio signals -- hearing devices -- frequency -- digital to analogue conversion -- hearing impairment -- analogue to digital converters -- microcontrollers -- human voice -- anti-aliasing filters -- pre-amplifier -- hearing aid design -- hearing aids -- rural areas -- Pakistan -- noise suppression -- frequency range; Biomedical engineering -- Periodicals; 610.28
• Languages: English
• ISSNs: 1752-6418

Abstract

A large number of hearing impaired people in rural sector of Pakistan cannot afford the high prices of digital hearing aids. Moreover, since the analogue devices amplify the speech and noise signals equally, they are not much flexible and have functional limitations. These problems can be solved with digital devices which are generally costly. In this research work, a microcontroller based cost-effective and portable hearing aid is designed and tested. The main components include sound detection circuit, microcontroller and a digital to analogue (DAC) convertor. Device is aimed to process human voice frequencies with an adjustable gain of up to 80 dB. It is tested with an input audio signal and it showed satisfactory results for low frequency signals up to 3.5 kHz which caters for the frequency range of most human voices. The system is now being developed for more effective noise suppression and broader frequency range.