Estimation of source location based on 2-D MUSIC and its application to speech recognition in cars

This paper proposes a speech recognition and an enhancement system for noisy car environments based on a microphone array. In the system, multiple microphones axe arranged in 2-dimensional space, surrounding the interior of a car, and the speaker's location is first estimated by our proposed HE (harmonic enhanced) 2-D MUSIC (MUltiple SIgnal Classification). Then, 2-D delay and sum (DS) is applied to enhance the target speech. Such pre-processing makes robust speech recognition in noisy car environments possible. In the proposed system, not only a driver, but also a fellow passenger can control car electronics by their voices no matter where they are. This is an advantage of the system as well. The results of the simulation and the preliminary experiment in a real car environment are presented to confirm the validity of our proposed system.