Barge-in- and noise-free spoken dialogue interface based on sound field control and semi-blind source separation

For hands-free spoken dialogue system, we propose an interface to eliminate known noise outputted by the dialogue system and unknown noise sufficiently by giving known source of the loudspeaker output. Moreover, elimination of known noise is reinforced by sound field control. The proposed method, at first, eliminates the loudspeaker output at the microphone points using sound field control with fixed filter coefficients. Next, the observed signals are processed by a source separation to eliminate both known and unknown noise. The conventional approach to combine acoustic echo canceller and adaptive beamformer requires double-talk detection (DTD) in noisy environment, which is difficult to implement. Due to no use of DTD, the proposed method works better than the conventional method in real environment. To prove this, we show in the experiment that the performance of the proposed method is superior to the performance limit of the conventional method.