Robust interference suppression and blind speech beamforming in room reverberant environments

In a microphone array system where references of interference are additionally available, the unwanted signals in the received signals can be removed using Widrow´s interference-cancelling (IC) approach. However, in the presence of crosstalk, IC can result in severe cancellation of the desired speech signal. In this paper, we propose a crosstalk-resistant method for joint interference suppression and blind speech signal beamforming. The proposed method is based on the Capon blind estimation principle, and is implemented using a powerful approximation tool, namely semidefinite relaxation. Simulation results show that the proposed method yields improved mean squared error performance compared with the IC-based method.