Binaural sound reproduction beamforming using spherical microphone arrays

Currently employed microphone arrays usually have a single-channel output, such that no spatial information can be perceived by a human listener. However, spatial information may trigger spatial mechanisms in the human auditory system which can improve the intelligibility. This work presents a mathematical framework for the binaural beamforming approach for the ideal and order-limited representation in the spherical harmonics domain. The performance of the proposed binaural beamformer is compared to that of a monaural maximum directivity beamformer using objective signal-based measures and subjective listening tests. It is shown that using the binaural beamformer results in higher intelligibility than the monaural beamformer.