CAJ | 학술논문

针对经验模态分解（empirical mode decomposition ，EMD）中存在的端点效应问题，提出一种边界局部特征尺度延拓的 EM D改进方法。通过计算信号边缘处与信号内部任何一段子波的匹配误差，确定信号的规律性强弱。在信号内在规律性较强的情况下，进行内在的匹配波形延拓，最大限度地维护信号的内在趋势；在信号规律性较弱的情况下，特别是信号边缘发生异常变化的情况下，只考虑边缘处的局部信息，根据边缘局部极值点的特征进行延拓，对延拓的极值点序列进行包络拟合，估计出均值曲线。该方法保证了信号有效数据的正确分解，提高了信号的分解精度，实现了EM D算法的改进。仿真实验验证了该方法能较好地抑制EM D端点效应。
침대경험모태분해（empirical mode decomposition ，EMD）중존재적단점효응문제，제출일충변계국부특정척도연탁적 EM D개진방법。통과계산신호변연처여신호내부임하일단자파적필배오차，학정신호적규률성강약。재신호내재규률성교강적정황하，진행내재적필배파형연탁，최대한도지유호신호적내재추세；재신호규률성교약적정황하，특별시신호변연발생이상변화적정황하，지고필변연처적국부신식，근거변연국부겁치점적특정진행연탁，대연탁적겁치점서렬진행포락의합，고계출균치곡선。해방법보증료신호유효수거적정학분해，제고료신호적분해정도，실현료EM D산법적개진。방진실험험증료해방법능교호지억제EM D단점효응。
For the end effects of EMD ,an improved extension method was proposed based on boundary local features .By calculating the mathcing errors between the boundary wave and any inter-nal signal wave ,the regularity strength of signal was determined .In the case that the inherent regular-ity was strong ,the internal wave form matching extension was conducted to maintain the inherent tendency to the greatest extent .While the signal was weak regularity and the signal edge was changed abnormally ,the local information at the edges was considered only to conduct the extreme point exten-sion .Thus the extreme points were used to fit envelope curve to realize extension .This method en-sures that the decomposition of valid data is correct ,and improves the decomposition accuracy .Simu-lation results show that the method can suppress end effect of EMD method .