Robust direction of arrival estimation for speech enhancement in noisy reverberant rooms

This paper describes an eigendecomposition based approach to estimate the direction of arrival (DOA) of speech or noise sources in a reverberant room by using a microphone array. Unitary ESPRIT, a DOA estimation algorithm for narrowband signals, is applied to these wideband signals, which results in DOA estimates for each frequency. A single estimate is then obtained by means of a histogram. The estimated DOAs of the speech source are used to enhance a noisy speech signal by means of a superdirective beamformer. Experiments in a noisy reverberant room showed a higher estimation accuracy, and thus a better speech enhancement performance, at low SNRs compared to other DOA estimation techniques.