A blind noise decorrelation approach with crystal arrays on designing post-filters for diffuse noise suppression

This paper describes a new framework for extracting the target signal in diffuse noise environments. We utilize crystal arrays, a certain class of symmetrical microphone arrays with crystal-like geometries, which enable interchannel decorrelation of isotropic noise without knowing the value of its covariance matrix. We refer to this decorrelation as blind noise decorrelation. Using an improved estimation of the signal power spectrum obtained by the blind noise decorrelation, the multichannel Wiener filter is properly implemented, which is the optimal estimator of the target signal in the minimum mean square error sense. Simulated experiments have shown the effectiveness of the proposed method.