MATLAB Implementation for Electrical Signal Processing: Baseline Wander and Power Line Interference Removal

This paper investigates methodologies for processing electrical signals, specifically addressing baseline wander and power line interference. For baseline wander processing, we first inject 0.5Hz baseline drift into the original signal using MATLAB's signal generation functions. The contaminated signal is then filtered through a 0.5Hz high-pass filter implemented with butterworth design (butter function) and zero-phase filtering (filtfilt). We perform comparative analysis between filtered and original waveforms, accompanied by frequency response characterization using freqz function. For power line interference mitigation, we introduce 50Hz frequency contamination through sinusoidal injection, then apply a 50Hz notch filter designed with narrowband rejection characteristics. The filtering results are compared against the original signal, with detailed filter response analysis using transfer function visualization. These processing techniques enhance understanding of electrical signal properties and provide foundational support for future research in biomedical signal processing and noise reduction applications.