Using spherical array receivers to extract scattering coefficients of room surfaces

Scattering coefficients (SCs) are crucial for modeling room sound fields in rooms. Due to the lack of SCs on many practical surfaces and room objects, this study aims to derive a relation between surface SCs and the angulardependent<br/>SCs obtained by a spherical receiver array in the room. The work is based on a computational approach. The sound field at a spherical receiver array is computed for a room with and without surface scattering at the room<br/>boundaries. A hybrid model of the Image Source Model and the Radiosity Model is used for this purpose. The sound field on the spherical receiver is then decomposed into plane waves, leading to ambisonic impulse responses<br/>(IRs). Then, the angular-dependent SCs are derived from these ambisonic IRs in both scenarios with a coherence method. Results show that angular-dependent SCs vary significantly depending on the apparent area of scattering<br/>surfaces as seen from the receiver, and a qualitative relationship between surface SCs and angular-dependent SCs is observed. This approach offers a promising framework for quantifying the scattering properties of room boundaries<br/>based on spherical array receivers.