A Study of Adaptive WDRC in Hearing Aids under Noisy Conditions
DOI:
https://doi.org/10.12970/2311-1917.2013.01.02.1Keywords:
Adaptive WDRC, GMAPA, speech enhancement, hearing aids, NAL-NL1.Abstract
Background noise poses a great challenge to the speech recognition capability of hearing-impaired patients fitted with hearing aid (HA) devices. In an HA system, a speech enhancement unit is generally employed to enhance the signal-to-noise ratio (SNR) of noisy speech in order to yield better speech understanding for HA users in noisy conditions. However, previous studies reported that a subsequent static amplification scheme, such as wide-dynamic-range compression (WDRC), may deteriorate the enhanced speech and thus decrease the speech recognition capability. This work examines the performance of a recently proposed adaptive WDRC (AWDRC) amplification scheme when used in conjunction with a speech enhancement method in HA signal processing. Experimental results demonstrate that when integrated with the same speech enhancement method, AWDRC outperforms WDRC, in terms of long-term SNRs, at several typical hearing loss conditions. The results suggest that AWDRC can be a better choice than WDRC when combining with speech enhancement to improve speech recognition capabilities for HA users in noisy conditions.
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