Blind source separation and Kalman filter-based speech enhancement in a car environment

In this paper, we present a speech enhancement method as a pre-processor in a car environment. For the friendly and safe use of the voice commander in a running car, non-stationary audio signals such as music and non-candidate speech should be reduced. Our technique is a two microphone-based one. It consists of two parts, i.e., blind source separation (BSS) and Kalman filtering. Firstly, BSS is operated as a spatial filter to deal with non-stationary signals and then car noise is reduced by Kalman filtering. The algorithm performance is tested with a speech recognizer. The results show that our algorithm can be very helpful for the voice commander in a car environment.