Optimal binaural LCMV beamformers for combined noise reduction and binaural cue preservation

Besides noise reduction an important objective of binaural speech enhancement algorithms is the preservation of the binaural cues of both desired and undesired sound sources. Recently, the binaural Linearly Constrained Minimum Variance (BLCMV) beamformer has been proposed that aims to preserve the desired speech component and suppress the undesired directional interference component while preserving the binaural cues of both components. Since the performance of the BLCMV beamformer highly depends on the amount of interference rejection determined by the interference rejection parameter, in this paper we propose several performance criteria to optimize the interference rejection parameters for the left and the right hearing aid. Experimental results show how the performance of the BLCMV beamformer is affected by the different optimal parameter combinations.