Extended Kalman Filter-Based Power Line Interference Canceller for Electrocardiogram Signal

Abstract

Cardiac diseases constitute a major root of global mortality and they are likely to persist. Electrocardiogram (ECG) is widely opted in clinics to detect countless heart illnesses. Numerous artifacts interfere with the ECG signal, and their elimination is vital to allow medical specialists to acquire valuable statistics from the ECG. The utmost artifact that is added to the ECG signal is power line interference (PLI). Numerous filtering methods have been employed in the literature to eliminate PLI from noisy ECG. This article proposes an extended Kalman filter (EKF)-based adaptive noise canceller (ANC) that comprises PLI frequency as a distinct model parameter. Thus, it is capable of tracking PLI with drifting frequency. The proposed canceller's performance is compared with state-space recursive least squares (SSRLSs) filter-based PLI canceling. The evaluation is carried out for four cases of PLI, that is, PLI with known amplitude and frequency, PLI with unknown amplitude and frequency, PLI with drifting amplitude and frequency, and PLI removal from a real-time ECG recording. The samples of the Massachusetts Institude of Technology (MIT)-Boston's Beth Israel Hospital (BIH) arrhythmia database are considered for the first three cases, whereas, for the fourth case, real ECG signal is taken from armed forces institude of cardiology, the national institude of heart diseases (AFIC/NIHD), Pakistan. Mean square error, frequency spectrum, and noise reduction are selected as performance metrics for comparison. Simulation results depict that the presented EKF-based ANC system outperforms the SSRLS-based ANC system and effectively eliminates PLI from ECG under all four investigated scenarios.

Pre-processing of ECG signal based on multistage filters

“…S. Tahir proposed the use of an extended Kalman filter for the purpose of canceling out the noise associated with an ECG signal [24]. The evaluation was performed for four cases of power line interference (PLI).…”

A novel fixed-point leaky sign regressor algorithm based adaptive noise canceller for PLI cancellation in ECG signals

“…A 34-bit fixed-point Normalized Least Mean Square (NLMS) and a 34-bit fixed-point Improved Proportional Normalized Least Mean Square (IPNLMS) based VLSI architectures were proposed for accurate Fetal Electro-CardioGram (FECG) and Fetal Heart Rate (FHR) processing in [14]. In [15], it was shown that the extended Kalman filter-based adaptive noise canceller system outperforms the state-space recursive least squares filter-based adaptive noise canceller system and effectively eliminates PLI from ECG signals. Moreover, the performance evaluation of both single stage and multistage adaptive noise cancellers using various adaptive algorithms was compared for the removal of 60 Hz PLI and other artifacts from the ECG signal in [16].…”