An FLMS based two-microphone speech enhancement system for in-car applications

Distributed microphone arrays enable a better compromise for the microphone position with respect to different speaker sizes. They also ensure robust noise reduction with respect to different noise sources. This paper proposes a frequency domain LMS (FLMS) based algorithm to combine the signals of two microphones. It is shown that noise correlation leads to a bias of the FLMS filter transfer function. To overcome this issue a noise cross-power estimator for estimating and correcting the filter bias is proposed.