  In this paper, we propose an efficient technique for estimating individual
power spectral density (PSD) components, i.e., PSD of each desired sound source
as well as of noise and reverberation, in a multi-source reverberant sound
scene with coherent background noise. We formulate the problem in the spherical
harmonics domain to take the advantage of the inherent orthogonality of the
spherical harmonics basis functions and extract the PSD components from the
cross-correlation between the different sound field modes. We also investigate
an implementation issue that occurs at the nulls of the Bessel functions and
offer an engineering solution. The performance evaluation takes place in a
practical environment with a commercial microphone array in order to measure
the robustness of the proposed algorithm against all the deviations incurred in
practice. We also exhibit an application of the proposed PSD estimator through
a source septation algorithm and compare the performance with a contemporary
method in terms of different objective measures.
