SPATIALLY ROBUST GSC BEAMFORMING WITH CONTROLLED WHITE NOISE GAIN

Adaptive beamforming is widely used for speech enhancement in telephony and speech recognition applications. We focus on scenarios with a single desired speaker in a non-stationary environmental noise. Many modern beamformers are designed using the desired speaker transfer function (TF), or the respective relative transfer function (RTF). If the relative source position is fixed, tracking the RTF can be avoided. On top of reducing the computational complexity, this may also circumvent the beamformer from enhancing competing sources. In this work, to target such applications, we propose a technique for obtaining a spatially robust generalized sidelobe canceler (GSC) beamformer with controlled white noise gain (WNG). The proposed implementation will introduce robustness to mismatch between the assumed and actual RTFs while maintaining sufficiently large WNG. It allows for high flexibility in shaping the desired response, while maintaining low computational complexity.