[01] Isiaka A. Alimi, Department of Electrical and Electronics Engineering, School of Engineering and Engineering Technology, Federal University of Technology, Akure, Nigeria. [02] Tusin D. Ebinowen, Department of Electrical and Electronics Engineering, School of Engineering and Engineering Technology, Federal University of Technology, Akure, Nigeria.

The spectral subtraction (SS) method is a well-known signal enhancement technique that reduces the effect of noise in a noisy signal in order to improve the signal quality. The SS works on the principle that noise spectrum estimate over the entire speech spectrum can be subtracted from the noisy signal. However, noise does not affect the speech signal uniformly over the entire spectrum at different frequency bands. Therefore, most implementations of the basic technique lead to anomaly known as “musical” tones artifacts in the enhanced signal. The abnormality can then be perceived as residual noise and speech distortion in the resulting signal. In this paper, we propose a multi-band spectral subtraction (MBSS) method using novel noise element suppression (NES). The proposed scheme gives comparatively better performance and the computation required is minimal. Furthermore, simulation results show that the proposed algorithm removes noise without removing the relatively low amplitude signal over the entire speech spectrum.

Speech Enhancement, Musical Noise, Spectral Subtraction, Noise Element Suppression, Multi-Band, Sub-Band

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