Performance improvement of Acoustic Echo and Noise Suppression using a priori SNR and Echo Spectrum Variance estimation Techniques

In this paper, an improved a priori SNR estimator is presented for speech enhancement in hands-free communication systems. The proposed a priori SNR estimation technique, based upon the Two-Step Noise Reduction (TSNR) algorithm, has flexibility and control over noise attenuation performance and speech distortion reduction. In addition, an efficient technique for estimating the Echo Spectrum Variance (ESV) is introduced. Simulation results demonstrate significant improvement of the Acoustic Echo and Noise Suppression (AENS) system in terms of Noise and Echo Attenuation performance and its ability to preserve the enhanced speech quality.