摘要
针对传统心电检测系统存在佩戴电极不方便和电极导电膏易脱水等问题,在研究分析电容耦合工作原理的基础上,设计了一种可穿戴容性耦合电极。针对这种可穿戴容性耦合电极,提出了一种改进小波阈值去噪算法,该算法结合心电信号与噪声小波系数分布特性,采用改进阈值函数对分解后小波系数量化处理并重构心电信号。利用MIT-BIH数据库验证,该算法能有效消除心电信号中的噪声干扰,相比平滑滤波、数学形态滤波和经验模式分解信噪比提高了10.72%,均方误差减小了27.29%。心电检测实验表明可穿戴容性耦合心电信号检测系统能够准确检测出人体心电信号主要特征。
In most traditional electrocardiogram( ECG) detection procedures,wet electrodes may cause problems of inconvenience and glue dehydrates over time. The paper designs a kind of wearable capacitive coupling electrode based on the principle of coupling capacity. Due to this kind of wearable capacitive coupling electrode,an improved wavelet threshold de-noising algorithm is proposed. The algorithm uses the improved threshold function to deal with wavelet coefficients after decomposition and reconstruct ECG signal combining the characteristics of wavelet coefficients of ECG signal and noise. The MIT-BIH database was used to validate the algorithm and it indicates that the algorithm can effectively eliminate the noise. The SNR increased by 10. 72% and the RMSE reduced by 27. 29%compared to the other methods,such as,smoothing filtering,morphological filtering and empirical mode decomposition.The results of the experiment show that the system can accurately detect the main characteristics of the ECG signal.
引文
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