2026, Vol. 7, Issue 1, Part A
Discrete Fourier transform based noise reduction in audio signals
Author(s): Wei-Chen Lin
Abstract: Audio signal quality degradation due to background noise remains a persistent challenge across communication, broadcasting, and recording industries. This research presents a spectral subtraction approach for noise reduction utilizing the Discrete Fourier Transform to separate noise components from desired audio content in the frequency domain [1]. The methodology transforms time-domain signals into frequency representations where noise characteristics can be estimated during speech pauses and subsequently subtracted from the composite spectrum. Implementation employed 2048-point DFT windows with 50% overlap and Hann windowing to minimize spectral leakage effects [2]. Testing across six distinct noise types revealed signal-to-noise ratio improvements ranging from 8.4 dB for impulsive noise to 29.4 dB for periodic hum contamination at 50/60 Hz power line frequencies. Processing efficiency achieved real-time capability on standard computing hardware, requiring only 12.4 ms to process one second of audio using optimized radix-2 FFT algorithms [3]. Perceptual quality evaluation using PESQ and STOI metrics confirmed that the noise reduction maintained speech intelligibility above 82% while achieving artifact suppression scores exceeding 71%. The spectral flooring technique with β = 0.02 effectively prevented musical noise artifacts that commonly plague spectral subtraction methods [4]. Comparative analysis against Wiener filtering demonstrated competitive performance with 23% lower computational requirements, making the DFT-based approach suitable for resource-constrained embedded applications. The research establishes practical guidelines for parameter selection based on noise characteristics and quality requirements [5].
DOI: 10.22271/27084531.2026.v7.i1a.111
Pages: 28-32 | Views: 22 | Downloads: 10
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How to cite this article:
Wei-Chen Lin. Discrete Fourier transform based noise reduction in audio signals. Int J Res Circuits Devices Syst 2026;7(1):28-32. DOI: 10.22271/27084531.2026.v7.i1a.111
