A microphone array for speech enhancement using multiresolution wavelet transform

This paper addresses the problem of enhancing a speech signal corrupted by interfering signals. A new noise reduction algorithm based on a logarithmic microphone array and the multiresolution wavelet transform is described. The proposed processing is applied in the time-spectral domain with respect to the logarithmic subband decomposition of the spectrum of each microphone signal. The advantage of the proposed method is that both the sub-array based beamforming operation and the post ltering are performed in the same transform domain without adding FFT processing. Computer simulation results show that our approach is effective for noise reduction. The technique can be used in hands-free voice communication applications operating in an adverse environment. In particular, it can be applied to improve speech signal pick-up for voice communication terminal.