Improved Time Delay Estimation Exploiting Redundancy in Microphone Arrays

Authors: Dirk Bechler, Kristian Kroschel

Abstract:

In general, a set of Time Difference Of Arrival (TDOA) estimates is used for 3D passive acoustic sound source localization with microphone arrays. In real environments the reliability of TDOAestimates is degraded due to noise and room reverberation. To determine the set of TDOAs, standard methods don't take advantage of all possible microphone pairs in a microphone array, using only one set of independent time delay estimates. In this work, the redundant information lying in the remaining dependent time delays is used to improve the robustness of the TDOA estimation. Experimental results for real data recorded in a noisy and reverberant office room are presented. The proposed methods show an absolute decrease of the percentage of false TDOA estimates of about 8 %, enhancing significantly the TDOA estimate reliability.