心磁和心电信号的混沌时间序列分析

Chaotic Time Series Analysis of Magntocardiography and Electrocardiography Signals

计算了一组心磁和心电检测信号的关联维数和最大李亚普诺夫(Lyapunov)指数.心磁和心电信号的关联维数分别在2.28±0.27和1.12±0.13范围内,最大Lyapunov指数分别在0.68±0.12和0.32±0.04范围内.对其它4组数据中心测点的计算结果也说明心磁和心电信号具有混沌特性.此外,结果显示心磁边缘测点的混沌吸引子与中心部分有明显差别,可用于分析信号的有效检测范围.

The correlation dimension （CD） and the maximum Lyapunov exponent （MLE） were explored on the basis of the magntocardiography （MCG） recordings and the synchronous electrocardiography （ECG） signals from an individual patient. The CD appears to vary between MCG and ECG, ranging 2, 28 ± 0.27 and 1.12 ± 0.13, as does the MLE, ranging 0.68 ± 0.12 and 0.32 ± 0.04. The results show that for both the MCG and ECG signals, chaos characteristics exist in the central measurement area in other four patients. The MCG chaotic attractors are different between the central portion and the margin of the chest, allowing valid t areas to be identified.