Improving robustness of adaptive beamforming for hearing devices

Authors

  • Alastair Moore Department of Electrical and Electronic Engineering, Imperial College, London, UK
  • Patrick Naylor Department of Electrical and Electronic Engineering, Imperial College, London, UK
  • Mike Brookes Department of Electrical and Electronic Engineering, Imperial College, London, UK

Abstract

Fixed beamforming for hearing aids is suboptimal due to mismatches in real-world situations between the assumed and encountered sound fields. Adaptive beamforming potentially provides better performance but may degrade it if the characteristics of the signal required by the design procedure are inaccurately estimated. This paper proposes a straightforward but sufficiently rich model for the sound field that can be used to increase the robustness of adaptive beamformer design. A method for estimating the model parameters is also presented. In reverberant acoustic conditions, the proposed method improves performance by > 1 dB even at −16 dB SNR, the lowest signal to noise ratio (SNR) tested. Furthermore, it is shown to be robust in a variety of acoustic conditions which do not conform to the sound field model, and to inaccurate steering of the array.

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Additional Files

Published

2020-05-01

How to Cite

Moore, A., Naylor, P., & Brookes, M. (2020). Improving robustness of adaptive beamforming for hearing devices. Proceedings of the International Symposium on Auditory and Audiological Research, 7, 305–316. Retrieved from https://proceedings.isaar.eu/index.php/isaarproc/article/view/2019-35

Issue

Section

2019/4. Novel directions in hearing-instrument technology