Angular region-wise speech enhancement for hands-free speakerphone

A novel speech enhancement method using a microphone array is implemented in a hands-free speakerphone prototype. The method can emphasise sound arriving from the angular region where speakers are located (speaker region) while effectively suppressing noise located in the other angular region (noise region). The method estimates the power spectral densities (PSDs) of sound sources located in each region, then calculates a postfilter that effectively reduces the noise. In the PSD estimation, the calculation complexity is reduced to make the method suitable for real-time implementation. Experiments were conducted to examine the performance of the proposed method. A drastic dropoff occurred in the resultant directivity between the regions, while constant sensitivity was maintained within the same region.

[1]  Michael S. Brandstein,et al.  Microphone Arrays - Signal Processing Techniques and Applications , 2001, Microphone Arrays.

[2]  Shoko Araki,et al.  Subband Based Blind Source Separation , 2005 .

[3]  K. Kobayashi,et al.  Enhancement of Sounds in a Specific Directional Area Using Power Spectra Estimated from Multiple Beamforming Outputs , 2008, 2008 Hands-Free Speech Communication and Microphone Arrays.

[4]  Don H. Johnson,et al.  Array Signal Processing: Concepts and Techniques , 1993 .

[5]  C.-C. Jay Kuo,et al.  Enhanced speech separation in room acoustic environments with selected binaural cues , 2009, IEEE Transactions on Consumer Electronics.

[6]  Kobayashi Kazunori,et al.  Angular region-wise speech enhancement for hands-free speakerphone , 2012 .

[7]  Seung Ho Han,et al.  Robust GSC-based speech enhancement for human machine interface , 2010, IEEE Transactions on Consumer Electronics.

[8]  R. Zelinski,et al.  A microphone array with adaptive post-filtering for noise reduction in reverberant rooms , 1988, ICASSP-88., International Conference on Acoustics, Speech, and Signal Processing.

[9]  Heinrich Kuttruff,et al.  Room acoustics , 1973 .

[10]  Jae S. Lim,et al.  Speech enhancement , 1986, ICASSP '86. IEEE International Conference on Acoustics, Speech, and Signal Processing.