Time-domain Beamforming for Room Acoustics Analysis based on Reverberant Field Estimation

This paper introduces a beamforming technique for room acoustic analysis, contrasting from most conventional methods by operating in the time domain rather than the frequency domain. The technique estimates the direction of arrival of early reflections and the reverberant field using impulse responses recorded by a planar microphone array. A significant contribution is the design of a relaxed linear forward operator that models sound propagation based on the geometric setup. The proposal novelly leverages the impulsive sound waves’ sparsity in space and time simultaneously under an optimization framework. Comparative evaluations with conventional beamformers using synthetic and real data from a reverberant room validate the efficacy of the proposed technique for room acoustics analysis, highlighting its ability to discern early reflections temporally and estimate the reverberant field.