Performance Comparison of Bilateral and Binaural MVDR-based Noise Reduction Algorithms in the Presence of DOA Estimation Errors

With the advent of wireless technology in hearing aids, it is currently possible to not only use the microphones of the left or the right hearing aid (bilateral configuration) but to use the microphones of both hearing aids (binaural configuration) to improve speech intelligibility in noisy environments. On the one hand, since a larger number of microphones is available, a better noise reduction performance can be achieved for the binaural configuration compared to the bilateral configuration. On the other hand, the sensitivity to DOA estimation errors is increased. In this paper, we objectively evaluate the performance of a bilateral and a binaural MVDR beamformer, which is steered towards the direction of the desired speech source using a DOA estimator based on a discriminative classifier. Simulation results show that in general the binaural MVDR beamformer shows a better performance compared to the bilateral MVDR beamformer even for very low input SNRs.