Onset zone detection using coherent focusing summation over multiple geometric positions

Abstract

A method includes receiving a multichannel input signal captured in an environment of a vehicle and, for each zone in the environment, performing speech detection by converting each frame in a sequence of frames of the multichannel input signal into a plurality of frequency sub-bands each having a cross-correlation matrix (CCM). For each sub-band, the method also includes applying a focusing matrix to the CCM to generate a corrected CCM, extracting eigenvalues from the corrected CCM, and determining an eigenvalue ratio between a highest and a second highest extracted eigenvalue. The method further includes calculating a median value of the eigenvalue ratios of the plurality of frequency sub-bands, determining a difference between the respective median values of the zones, and when an absolute value of the difference between the respective median values of the zones is greater than a threshold, generating an initial detection of speech indication.