In the presence of background noise, the perceptual loudness of speech signal significantly decreases resulting in the deterioration of intelligibility and clarity. In this paper, we propose a novel approach to enhance the quality of speech signal when the additive noise cannot be directly controlled. Specifically, we propose an approach which reinforces the speech signal so that the partial loudness in each band can be maintained to the level almost the same to that measured without the effect of background noise. To find a suitable reinforcement rule, the loudness perception model proposed by Moore et al.  is adopted. Experimental results show that the loudness of the original noise-free speech can be restored by the proposed reinforcement algorithm and the proposed algorithm can enhance the perceived quality of speech signal under various noise environments.
Bibliographic reference. Shin, Jong Won / Lim, Woohyung / Sung, Junesig / Kim, Nam Soo (2007): "Speech reinforcement based on partial specific loudness", In INTERSPEECH-2007, 978-981.