A model for the temporal evolution of the spatial coherence in decaying reverberant sound fields

TL;DR

This paper develops a model for the changing spatial coherence in decaying reverberant sound fields within rectangular rooms, accounting for room properties and sensor orientation, extending beyond the isotropic assumption.

Contribution

It introduces a novel model for the spatial coherence evolution in decaying reverberant fields, incorporating room geometry and sensor orientation, and unifies isotropic models as special cases.

Findings

Model captures coherence dependence on room dimensions and surface reflectivity.

Model is independent of source and sensor positions within the room.

Includes isotropic and cylindrical models as special cases.

Abstract

Reverberant sound fields are often modeled as isotropic. However, it has been observed that spatial properties change during the decay of the sound field energy, due to non-isotropic attenuation in non-ideal rooms. In this letter, a model for the spatial coherence between two sensors in a decaying reverberant sound field is developed for rectangular rooms. The modeled coherence function depends on room dimensions, surface reflectivity and orientation of the sensor pair, but is independent of the position of source and sensors in the room. The model includes the spherically isotropic (diffuse) and cylindrically isotropic sound field models as special cases.