东北大学学报（自然科学版）
東北大學學報（自然科學版）
동북대학학보（자연과학판）
Journal of Northeastern University (Natural Science)
2015年
11期
1535-1538,1547
,共5页
希尔伯特 -黄变换%经验模态分解%欠冲现象%包络线拟合%单调分段三次多项式插值
希爾伯特 -黃變換%經驗模態分解%欠遲現象%包絡線擬閤%單調分段三次多項式插值
희이백특 -황변환%경험모태분해%흠충현상%포락선의합%단조분단삼차다항식삽치
Hilbert-Huang transform%empirical mode decomposition%undershoot phenomenon%envelope fitting%monotone pieceWise cubic polynomial interpolation
针对经验模态分解(empirical mode decomposition,EMD)过程中存在的包络线拟合问题,提出了一种精确消除欠冲现象的改进算法。该算法首先确定利用三次样条插值(cubic spline interpolation,CSI)进行包络线拟合时所产生的欠冲区间,然后通过单调分段三次多项式插值法对欠冲区间包络线进行补偿。该改进的包络线能紧紧地包住原始信号,而不影响信号本身的特征,尽可能保持前包络线的平滑性。仿真结果表明,提出的方法可以有效地消除由 CSI 所造成的欠冲现象,拟合出更好的包络线,进一步提高 EMD 的分解精度。
針對經驗模態分解(empirical mode decomposition,EMD)過程中存在的包絡線擬閤問題,提齣瞭一種精確消除欠遲現象的改進算法。該算法首先確定利用三次樣條插值(cubic spline interpolation,CSI)進行包絡線擬閤時所產生的欠遲區間,然後通過單調分段三次多項式插值法對欠遲區間包絡線進行補償。該改進的包絡線能緊緊地包住原始信號,而不影響信號本身的特徵,儘可能保持前包絡線的平滑性。倣真結果錶明,提齣的方法可以有效地消除由 CSI 所造成的欠遲現象,擬閤齣更好的包絡線,進一步提高 EMD 的分解精度。
침대경험모태분해(empirical mode decomposition,EMD)과정중존재적포락선의합문제,제출료일충정학소제흠충현상적개진산법。해산법수선학정이용삼차양조삽치(cubic spline interpolation,CSI)진행포락선의합시소산생적흠충구간,연후통과단조분단삼차다항식삽치법대흠충구간포락선진행보상。해개진적포락선능긴긴지포주원시신호,이불영향신호본신적특정,진가능보지전포락선적평활성。방진결과표명,제출적방법가이유효지소제유 CSI 소조성적흠충현상,의합출경호적포락선,진일보제고 EMD 적분해정도。
Due to the envelope fitting problem exists in the process of empirical mode decomposition,an improved algorithm Was proposed Which could eliminate the undershoot phenomenon exactly.Firstly,in this improved algorithm,the cubic spline interpolation Was used to determine the regions of undershoot Which generated during the execution of envelope fitting. Secondly,the envelope intervals of undershoot regions Were compensated by the monotone pieceWise cubic polynomial interpolation.The original signal could be Wrapped tightly by this modified envelope,Which did not affect the characteristics of signal itself,and could keep the smoothness of previous envelope as Well as possible.The simulation results shoWed that the undershoot phenomenon caused by cubic spline interpolation could be effectively eliminated and the envelope could be obtained better by this algorithm.In addition,the accuracy of empirical mode decomposition could be further improved.
