Beamforming for a spherical-aperture microphone

Spherical microphone arrays have been recently studied for sound analysis and beamforming. Spherical microphone arrays have the advantage of spherical symmetry facilitating three-dimensional analysis. Performance of microphone arrays at the high-frequency range is typically limited by aliasing, which is a result of the spatial sampling process. A potential approach to avoid spatial aliasing is by using continuous sensors, in which spatial sampling is not required. This paper presents a beamforming technique for a continuous spherical-aperture microphone design. The beamforming technique is based on finding real-weighted coefficients for the sensor, which are required to ensure its feasibility.

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