Speech Noise Reduction System Based on Frequency Domain Ale Using Modified Dft Pair

This paper presents the speech noise reduction system based on frequency domain adaptive line enhancer using the modified DFT (MDFT) pair. The adaptive line enhancer (ALE) is effective to extract sinusoidal signals blurred by broadband noise and utilizes only one microphone; therefore, it is suitable for realization of speech noise reduction in the portable electronic devices. In the ALE, an input signal is generated by delaying a desired signal by the de-correlation parameter, which makes the noise in the input signal de-correlated with that in the desired one. In this paper, we propose to set the decorrelation parameter in the frequency domain signal and adjust it to an optimal value. Moreover, we introduce the window function for suppressing the spectral leakage in the MDFT. The performance of the proposed noise reduction system is confirmed through computer simulations.