TDOA Estimation of Speech Source in Noisy Reverberant Environments

Sound source localization is important in many applications, but noise and reverberation make the time difference of arrival (TDOA) estimation a challenging problem. In this work, we propose two novel methods to effectively estimate TDOA in noisy and reverberant environments. Our methods exploit the linear phase structure across frequencies in a steering vector (SV). To reduce potential noise and mathematical issues, we utilize absolute phases of SVs. We convert TDOA estimation into an optimization problem that is solvable by Newton's method. We conducted experimental evaluations in simulated acoustic conditions. In conditions with moderate-to-high input SNR and low reverberation, our fast-search method is superior in TDOA accuracy and is very efficient in computation. In conditions with low input SNR and high reverberation, our detailed-search method shows strong robustness and maintains advantageous performance in TDOA estimation.