Effect of interchannel coherence on conditioning and misalignment performance for stereo acoustic echo cancellation

It is well known that the performance in terms of misalignment of adaptive algorithms, in general, is dependent on the conditioning of the input signal covariance matrix. For two-channel (stereophonic) adaptive algorithms, this performance is further degraded by the high interchannel coherence between the two input signals. In this paper, we establish the relationship between interchannel coherence of the two input signals and condition of the corresponding covariance matrix for stereo acoustic echo cancellation application. We further show how this relationship affects the misalignment performance of a two-channel frequency-domain adaptive algorithm. We provide simulation results for both WGN and speech input to verify our mathematical analysis.