An Improved Speech Enhancement Algorithm Based on Wavelets for Mobile Communication

This paper depicts an improved speech enhancement method based on wavelets techniques, with the goal of ameliorating the speech quality for mobile phones. In the developed algorithm, optimized filters are designed and used as mothers wavelets for the classical algorithm of speech enhancement based on discrete wavelet transform. The cutoff frequency of the optimized wavelets filters is iteratively adjusted in order to satisfy the perfect reconstruction conditions. The evaluation of performances in the term of the noise reduction and the perceptual quality proves the efficiency of the optimized algorithm in the field of the noise reduction. The developed algorithm is evaluated for different noisy conditions with stationary and non stationary noise.