An alternate approach to adaptive beamforming using SRP-PHAT

An important application for microphone arrays is to extract high-quality output from a single wideband source in multi-source and adverse environments. Methods based on blind-source separation and beamforming have been proposed in the literature. In this paper, we propose a new algorithm for isolating sources which may be considered an alternate approach to adaptive beamforming. The proposed method assigns every time-frequency point to one of the sources in the environment or as background noise using an SRP-PHAT-based discriminator. It then creates the desired source´s output by spectrally subtracting the inappropriate time-frequency points. After giving the details of the procedure, we show results from real data from our large-aperture microphone array. Though, clearly a relatively small subset, listening results to date for two or three talkers have yielded high-quality isolations. For two talkers, in particular, results are presented which indicate that the method correctly identifies and removes about 90% of those time-frequency points where the interfering signal is dominant, without affecting the desired signal significantly.