Robust noise PSD estimation for binaural hearing aids in time-varying diffuse noise field

In this paper, we present an unsupervised noise PSD estimation algorithm for binaural hearing aids in a time-varying diffuse noise field. It is shown that the noise PSD can be obtained from the eigenvalues of the input covariance matrix together with the noise coherence function effective at low frequencies. To reduce the estimation bias due to fast smoothing, pre- and post-compensation methods are proposed. The proposed algorithm is able to track non-stationary noise PSD without tracking delay or underestimation problems. Its performance is independent of the target speech direction and input SNR. Results of the objective parameter evaluation demonstrate the superiority of the proposed algorithm over conventional techniques.