中国物理B ›› 2010, Vol. 19 ›› Issue (5): 58701-058701.doi: 10.1088/1674-1056/19/5/058701
符懋敬1, 庄建军1, 展庆波1, 邵毅1, 宁新宝1, 侯凤贞2
Fu Mao-Jing(符懋敬)a), Zhuang Jian-Jun(庄建军)a)†, Hou Feng-Zhen(侯凤贞)a)b), Zhan Qing-Bo(展庆波) a),Shao Yi(邵毅)a), and Ning Xin-Bao(宁新宝)a)
摘要: In this paper, the ensemble empirical mode decomposition ({EEMD}) is applied to analyse accelerometer signals collected during human normal walking. First, the self-adaptive feature of {EEMD} is utilised to decompose the accelerometer signals, thus sifting out several intrinsic mode functions {(IMFs}) at disparate scales. Then, gait series can be extracted through peak detection from the eigen {\rm IMF} that best represents gait rhythmicity. Compared with the method based on the empirical mode decomposition ({EMD}), the {EEMD}-based method has following advantages: it remarkably improves the detection rate of peak values hidden in the original accelerometer signal, even when the signal is severely contaminated by the intermittent noises; this method effectively prevents the phenomenon of mode mixing found in the process of {EMD}. And a reasonable selection of parameters for the stop-filtering criteria can improve the calculation speed of the {EEMD}-based method. Meanwhile, the endpoint effect can be suppressed by using the {auto regressive and moving average} model to extend a short-time series in dual directions. The results suggest that {EEMD} is a powerful tool for extraction of gait rhythmicity and it also provides valuable clues for extracting eigen rhythm of other physiological signals.
中图分类号: (Biological signal processing)