Robust 3D Localization and Tracking of Sound Sources Using Beamforming   and Particle Filtering
  In this paper we present a new robust sound source localization and tracking method using an array of eight microphones (US patent pending) . The method uses a steered beamformer based on the reliability-weighted phase transform (RWPHAT) along with a particle filter-based tracking algorithm. The proposed system is able to estimate both the direction and the distance of the sources. In a videoconferencing context, the direction was estimated with an accuracy better than one degree while the distance was accurate within 10% RMS. Tracking of up to three simultaneous moving speakers is demonstrated in a noisy environment. 
Jean-Marc Valin, Fran\c{c}ois Michaud, Jean Rouat
cs.RO cs.SD