Comparison of reduced-bandwidth MWF-based noise reduction algorithms for binaural hearing aids

in a binaural hearing aid noise reduction system, binaural output signals are generated by sharing information between the two hearing aids. When each hearing aid has multiple microphones and all microphone signals are transmitted between the hearing aids, a significant noise reduction can be achieved using the binaural multi-channel Wiener filter (MWF). To limit the number of signals being transmitted between the hearing aids, in order to comply with bandwidth constraints of the binaural link, this paper presents reduced-bandwidth MWF-based algorithms, where each hearing aid uses only a filtered combination of the contralateral microphone signals. One algorithm uses the output of a monaural MWF on the contralateral microphone signals, whereas a second algorithm involves a distributed binaural MWF scheme. Experimental results compare the performance of the presented algorithms.