Department of Electronics and Communication Engineering, Pondicherry Engineering College, Puducherry-605014, India.
Biomed Phys Eng Express. 2021 Oct 8;7(6). doi: 10.1088/2057-1976/ac2aee.
Electroencephalogram (EEG) signals are crucial to Brain-Computer Interfacing (BCI). However, these are vulnerable to a variety of unintended artifacts that could negatively impact the precise brain function assessment. This paper provides a new algorithm to eliminate Electrical Shift and Linear Trend artifact (ESLT) in EEG using Singular Spectrum Analysis (SSA) and Enhanced local Polynomial (LP) Approximation-based Total Variation (EPATV). The contaminated single channel EEG is subdivided into multiple bands of frequency components by SSA. In order to acquire all LP and TV components, EPATV filtering is applied over the contaminated component frequency band. Filtered sub-signal is collected by subtracting both the LP and TV components from the component contaminated frequency band. Then, the addition of filtered sub-signal and remaining SSA frequency band components yield the final denoised EEG signal. The effectiveness of the proposed method in this paper is evaluated using the data obtained from three databases and compared with the existing methods. From the extensive simulation results, it is inferred that the algorithm discussed in the paper is effective when compared the existing methods, exhibiting a highest averaged Correlation Coefficient (CC) of 0.9534, averaged Signal to Noise Ratio (SNR) of 10.2208dB, lowest averaged Relative Root Mean Square Error (RRMSE) value 0.2787 and averaged Mean absolute Error (MAE) inband value of 0.0557. The algorithm presented in this paper may be a viable choice for extracting ESLT artifact from a small streaming section of the EEG without requirement of the initial calibration or enormous EEG data.
脑电图 (EEG) 信号对于脑机接口 (BCI) 至关重要。然而,这些信号容易受到各种意外伪影的影响,从而对精确的大脑功能评估产生负面影响。本文提出了一种使用奇异谱分析 (SSA) 和增强局部多项式 (LP) 逼近的总变差 (EPATV) 消除脑电图中电移和线性趋势伪影 (ESLT) 的新算法。通过 SSA 将受污染的单通道脑电图细分为多个频率分量带。为了获取所有 LP 和 TV 分量,在受污染的分量频带上方应用 EPATV 滤波。通过从受污染的分量频带中减去 LP 和 TV 分量来收集滤波后的子信号。然后,通过将滤波后的子信号和剩余的 SSA 频率分量相加,得到最终的去噪 EEG 信号。本文通过三个数据库获得的数据评估了所提出方法的有效性,并与现有方法进行了比较。从广泛的仿真结果推断,与现有方法相比,本文所讨论的算法是有效的,其平均相关系数 (CC) 最高为 0.9534,平均信噪比 (SNR) 为 10.2208dB,平均相对均方根误差 (RRMSE) 值最低为 0.2787,平均带内均方误差 (MAE) 值为 0.0557。与需要初始校准或大量 EEG 数据的情况相比,本文提出的算法可能是从小部分 EEG 流段中提取 ESLT 伪影的可行选择。