Improving robustness of adaptive beamforming for hearing devices


  • 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


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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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



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