Noise Reduction in Car Speech

This paper presents properties of chosen multichannel algorithms for speech enhancement in a noisy environment. These methods are suitable for hands-free communication in a car cabin. Criteria for evaluation of these systems are also presented. The criteria consider both the level of noise suppression and the level of speech distortion. The performance of multichannel algorithms is investigated for a mixed model of speech signals and car noise and for real signals recorded in a car.

Derivation of Criterion Suitable for Evaluation of Multichannel Noise Reduction Systems for Speech Processing

This paper deals with the theoretical derivation of the Noise Reduction criterion suitable for evaluation of multichannel noise reduction system performance. This criterion is suitable for noise suppression assessment and thus serves as an important step in the development of noise reduction systems. Noise reduction is evaluated in dependence on spatial coherence. The derivations are made for five basic multichannel systems, Delay and sum beamformer, Beamformer with adaptive postprocessing, Generalized sidelobe canceller, Linearly constrained beamformer, and Modified coherence filter