Spatial decomposition using adaptive beamforming to generate dynamic impulse responses for virtual sound field synthesis

Abstract

Sound field decomposition analysis of room impulse responses (IRs) was performed for temporal and spatial structures at different positions in a real hall using a 32-channel spherical microphone array. Spherical microphone arrays can be used to analyse the sound field independently of the directivity of the acoustic behaviour, and they can be used to reconstruct the sound field. Adaptive beamforming techniques, such as Minimum Variance Distortionless Response (MVDR) spatial spectrum estimate, were employed to perform directional measurements and for spatial characterization of sound. Using the estimation of spatial analysis, dynamic directional impulse responses (DDIRs) were generated that explained the influence of surfaces of the hall on strong specular reflections. From the DDIRs, various sound field patterns can be synthesized for virtual reality environment.