Speech intelligibility enhancement through binaural signal processing

Authors

  • Jorge Mejia National Acoustic Laboratories Sydney, Australia; The Hearing CRC, Australia
  • Harvey Dillon National Acoustic Laboratories Sydney, Australia; The Hearing CRC, Australia
  • Simon Carlile Auditory Neuroscience Laboratory, the University of Sydney, Australia

Abstract

Spatial separation of target speech from distracting sounds greatly assists the listener to segregate the sounds, and hence better understand the target speech. Consequently, listening can occur in poorer signal-to-noise ratios (SNRs). Bilateral beamformers, which combine microphone output signals from both sides of the head, can improve SNR, but in the process remove interaural difference cues, and hence remove the ability to segregate the target from distracting sounds on the basis of spatial separation. This spatial cue removal decreases the speech intelligibility bene ts provided by the beamformer. Some techniques aim to retain the spatial cues in a beamformer output but in the process constrain its directional ef ciency. An alternative technique proposed by Mejia et al., [WIPO Pub. No: WO/2007/137364 (2007)] exploits the perceptual suppression of early re ections (known as the precedence effect) through combination of omni-directional precedent sounds with highly directional processed sound. The enhancement produces intelligibility scores much higher than those produced by bilateral beamformer outputs in the absence of precedent sounds. This paper will describe the strategy of spatial enhancement and discuss the outcome from a subjective study intended to evaluate the technology.

References

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Mejia, J., Dillon, H., and Carlile S. (2007). “A method and system for enhancing the intelligibility of sounds,” WIPO Pub. No: WO/2007/137364.

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Additional Files

Published

2009-12-15

How to Cite

Mejia, J., Dillon, H., & Carlile, S. (2009). Speech intelligibility enhancement through binaural signal processing. Proceedings of the International Symposium on Auditory and Audiological Research, 2, 417–424. Retrieved from https://proceedings.isaar.eu/index.php/isaarproc/article/view/2009-42

Issue

Vol. 2 (2009): Binaural Processing and Spatial Hearing

Section

2009/4. Recent concepts in binaural cochlear-implant and hearing-aid processing

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