Multi-channel systems containing a Delay&Sum-Beamformer have been previously combined with post-filters to achieve higher speech enhancement in noisy conditions. Problems occuring in the lower frequency regions were compensated by applying a Wiener weighting rule or spectral subtraction. We extend this by referring to the log-STSA rule of Ephraim-Malah. Furthermore, we introduce a psychoacustically motivated post-filter based on the one presented by Gustafsson for single-channel systems [1]. Relying on Li's subband approach [2] we derive an algorithm which exploits the advantage of multi-channel systems in order to estimate those quantities necessary for computing the psychoacoustic weighting rule.
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