A two-microphone noise reduction scheme for hands-free telephony in a car environment

This paper introduces a new noise reduction scheme for hands-free telephony in a car environment. First, a comparative study on the investigated time-domain and frequency-domain noise reduction methods are given. Then, the proposed algorithm utilises the time-domain Double Affine Projection (DAP) algorithm based on a subband structure. The DAP algorithm with high projection-order is suggested for operation in the low-frequency band, whereas a lower projection-order of the DAP algorithm can be applied to the high-frequency band. Simulation results suggest improved performance of the proposed noise reduction scheme in terms of noise attenuation and preservation of speech spectral components of the enhanced speech signals.