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Optimized Denoising of ECG and EEG Signals Using Discrete Wavelet Transform: A Comparative Study of Wavelet Types and Thresholding Techniques

Authors:

Mohammed Ahmed Moh., Yasin Yousif Al-Aboosi, Hussein A. Abdualnabi, Hussein Yasin Al-Aboosi

DOI:

Abstract:

Biomedical signals, specifically Electrocardiograms (ECG) and Electroencephalograms (EEG), using Particle Swarm Optimization (PSO) integrated with Discrete Wavelet Transform (DWT). Unlike traditional methods that rely on fixed thresholding, the proposed approach dynamically optimizes the selection of wavelet families (Daubechies, Coiflet, Symlet), decomposition levels, and thresholding parameters to maximize the Signal-to-Noise Ratio (SNR) while minimizing the Mean Squared Error (MSE). To ensure statistical validation, the framework was tested on 30 diverse records from the MIT-BIH and PhysioNet databases, corrupted with synthetic noise to simulate clinical interference. Results demonstrate that the PSO-optimized Symlet 8 (sym8) configuration significantly outperforms standard DWT methods, achieving an average SNR improvement of 19.88 dB for ECG and 15.57 dB for EEG. Statistical significance was confirmed via a paired t-test (p < 0.05), proving the robustness of the optimized model in preserving critical diagnostic features like the QRS complex and spike-wave discharges. This study bridges the gap between theoretical denoising and automated clinical diagnostics, offering a scalable model for real-time patient monitoring systems.

Keywords:

Biomedical Signal Processing, DWT, ECG Denoising, EEG Denoising, SNR

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