Robust speaker DOA estimation with single AVS in bispectrum domain

For mobile speech application, speaker DOA estimation accuracy, interference robustness and compact physical size are three key factors. Considering the size, we utilized acoustic vector sensor (AVS) and proposed a DOA estimation algorithm previously [1], offering high accuracy with larger-than-15dB SNR but is deteriorated by nonspeech interferences (NSI). This paper develops a robust speaker DOA estimation algorithm. It is achieved by deriving the intersensor data ratio model of an AVS in bispectrum domain (BISDR) and exploring the favorable properties of bispectrum, such as zero value of Gaussian process and different distribution of speech and NSI. Specifically, a reliable bispectrum mask is generated to guarantee that the speaker DOA cues, derived from BISDR, are robust to NSI in terms of speech sparsity and large bispectrum amplitude of the captured signals. Intensive experiments demonstrate an improved performance of our proposed algorithm under various NSI conditions even when SIR is smaller than 0dB.