Enhancement of speech signal by originating computational iteration using SAF

Abstract

Numerous environmental sources of noise and distortion can degrade the quality of the speech signal in a communication system. This study explores the effects of these intrusive sounds on speech applications and introduces some techniques for reducing the influence of noise and, enhancing the acceptability and intelligibility of the speech signal. In this paper, a noise reduction system uses single -microphone method in time domain to improve signal to noise ratio (SNR) of noise contaminated speech. In the early phase of noise reduction, the amount of noise is estimated from the valley of the spectrum based on the harmonic properties of noisy speech, called minimum value sequences (MVS). Therefore, we use the estimated degree of noise (EDON) [1] to adjust the amplitudes of the MVS. The base of the proposed method is to estimate noise continuously on a frame-by-frame basis without the aid of voice activity detector (VAD)[2]. This research uses single-channel adaptive filter (SAF) to reduce time and cost for maximum noise reduction. For this, we propose a minimum computational iteration number (CIN) and generated an equation from set values of SNR and EDON. By adopting the proposed iteration number, the planned system becomes computationally inexpensive and the signal resurgence difficulty is limited in the silent portion. To derive the proposed iteration number equation, we use the third degree parabola equation and least squares solution for the coefficients of EDON.