Finite Impulse Response Bank Filter for Electroencephalographic Artifacts Removal


The recording of brain's electrical activity over a period of time is called electroencephalogram EEG signal. EEG became cardinal tool for diagnosing and managing malfunctions and various brain disorders. It is very complex to analyze continuous EEG signals. These signals can be categorized to different kinds according to the frequency: Delta (0.5 – 4Hz), Theta (4 -7.5Hz), Alpha (7.5 – 12Hz), Beta (12 -30Hz), and Gamma (above 30Hz). Since EEG signals are categorized by their very small amplitudes, they can be easily polluted by noise. These noises are called the artifacts. These artifacts need to be removed before processing and analyzing the EEG signal. In general, an EEG signal which represents brain neuronal activity is contaminated with noises, artifacts, and external interferences. Therefore it is important to separate the required frequency band information from such noises. Different methods for noise and artifact removing are available and implemented. Filtering these interference signals might remove some relevant EEG information, and therefore care must be taken while choosing one of the preprocessing methods. This paper presents a detail analysis of EEG de-noising using law pass Butterworth filter, packet wavelet transforms (PWT), and FIR bank filter. All the above methods are simulated and tested using MATLAB 2013 software environment and their performance evaluation can be done by measuring the parameters like SNR, PSNR, MSE and MAE. The EEG database is freely acquired from MIT-BIH arrhythmia database. This EEG signals was polluted with white random external noise. The FIR bank filter gives the optimal noise removal results according to measuring parameters.