Robust Indoor Speaker Localization in the Circular Harmonic Domain

In this article, modal signal processing using circular sensor arrays has been shown to be an attractive way for speaker localization, due to the fact that it enables high flexibility in sound field analysis, which inherently supports wideband acoustic sources and provides a frequency invariant beampattern. However, the existing circular harmonic direction-of-arrival (DOA) estimation approaches suffer from the following problems: first, depending strongly on the characteristics of sensor arrays; second, the presence of singularity when using Bessel function of the first kind; and third, being sensitive to noisy and reverberant environments. To combat these problems, this article proposes a robust indoor speaker localization method that incorporates circular harmonic pseudointensity vector through joining the least-squares decomposition and the spatial processing with a small-sized sensor array. The root mean square error of DOA estimation of the proposed method is compared with those published approaches in simulations for different noise levels and reverberation times. In addition, the superior performance of the proposed indoor speaker localization method is validated by using speech recordings in a real-world acoustic environment.