PSD Estimation of Multiple Sound Sources in a Reverberant Room Using a Spherical Microphone Array

TL;DR

This paper introduces an efficient spherical microphone array-based method for estimating source PSDs in reverberant environments, enabling better multi-source separation without complex beamformer design.

Contribution

The method leverages spatial correlation of spherical harmonics to estimate PSDs, allowing for more sources and simplifying beamformer design compared to traditional approaches.

Findings

Effective in reverberant and non-reverberant rooms

Handles more sources than conventional methods

Improves source separation using estimated PSDs

Abstract

We propose an efficient method to estimate source power spectral densities (PSDs) in a multi-source reverberant environment using a spherical microphone array. The proposed method utilizes the spatial correlation between the spherical harmonics (SH) coefficients of a sound field to estimate source PSDs. The use of the spatial cross-correlation of the SH coefficients allows us to employ the method in an environment with a higher number of sources compared to conventional methods. Furthermore, the orthogonality property of the SH basis functions saves the effort of designing specific beampatterns of a conventional beamformer-based method. We evaluate the performance of the algorithm with different number of sources in practical reverberant and non-reverberant rooms. We also demonstrate an application of the method by separating source signals using a conventional beamformer and a Wiener post-filter designed from the estimated PSDs.