Efficient interferer cancelation based on geometrical information of the reverberant environment

This paper concerns the problem of separation of wideband acoustic sources in reverberant environments. The idea is to perform separation in two stages: first we assess the position of desired and interferer sources and then we use this knowledge to steer the sensitivity of a microphone array towards the desired source. Notice, however, that the steering of a null towards its DOA is not sufficient to perform cancellation of the interferer in reverberant environments, due to reflections. For this reason, nulls of the beampattern are steered not only towards the interferer location but also towards its most important echoes. The DOAs of the echoes are predicted using a fast beam tracing algorithms. Experimental results confirm that an improvement Signal to Interference Ratio of 5 dB over Blind Source Separation techniques can be reached in a moderately reverberant environment with moving sources.