Reference Microphone Selection for MWF-based Noise Reduction Using Distributed Microphone Arrays

Using an acoustic sensor network, consisting of spatially distributed microphones, a significant noise reduction can be achieved with the centralized multi-channel Wiener filter (MWF), which aims to estimate the desired speech component in one of the microphones, referred to as the reference microphone. However, since the distributed microphones are typically placed at different locations, the selection of the reference microphone has a significant impact on the performance of the MWF, largely depending on the position of the desired source with respect to the microphones. In this paper, different optimal and suboptimal reference selection procedures are presented, both broadband and frequency-dependent. Experiment results show that the proposed procedures yield better performance than an arbitrarily selected reference microphone.