Adaptive augmented cubature Kalman filter/smoother for ECG denoising

Area of Science:

• Biomedical Engineering
• Signal Processing
• Computational Science

Background:

• Model-based Bayesian approaches are crucial for Electrocardiogram (ECG) processing.
• Accurate parameter selection, especially noise covariance matrices, is vital for filter performance.
• Existing Kalman filters struggle with diverse noise types and heart rate variability in ECG signals.

Purpose of the Study:

• To develop an adaptive augmented cubature Kalman filter/smoother (CKF/CKS) for robust ECG signal denoising.
• To enhance filter efficiency with dynamic time warping for heart rate variability.
• To reduce the computational complexity of CKF/CKS in ECG processing.

Main Methods:

• An adaptive augmented cubature Kalman filter/smoother (CKF/CKS) was developed, updating noise covariance matrices adaptively.
• Dynamic time warping was integrated to handle heart rate variability.
• Computational complexity reduction techniques were applied to the CKF/CKS.
• Performance was evaluated against Extended Kalman Filter/Smoother (EKF/EKS), Unscented Kalman Filter/Smoother (UKF/UKS), and Ensemble Kalman Filter (EnKF).
• Experiments used normal ECG segments from the MIT-BIH Normal Sinus Rhythm Database with added stationary and non-stationary noise.

Main Results:

• The proposed adaptive augmented CKF/CKS demonstrated superior denoising performance compared to EKF/EKS, UKF/UKS, and EnKF.
• Outperformance was consistent across both stationary white Gaussian noise and non-stationary muscle artifact noise.
• Key metrics including Signal-to-Noise Ratio (SNR) improvement, PRD, correlation coefficient, and MSEWPRD showed significant advantages for the proposed method.

Conclusions:

• The adaptive augmented CKF/CKS offers a significant advancement in ECG signal processing and denoising.
• The filter's adaptability to varying noise conditions and heart rate variability makes it highly effective.
• This approach provides a computationally efficient and accurate solution for enhancing ECG signal quality.