电测与仪表
電測與儀錶
전측여의표
ELECTRICAL MEASUREMENT & INSTRUMENTATION
2014年
17期
58-61
,共4页
时频分解%经验模态分解%时间尺度分层%模态分解法%Harr小波分解
時頻分解%經驗模態分解%時間呎度分層%模態分解法%Harr小波分解
시빈분해%경험모태분해%시간척도분층%모태분해법%Harr소파분해
time-frequency decomposition%empirical mode decomposition%time scale layers%the modal decomposi-tion method%Harr wavelet decomposition
经验模态分解法( EMD变换),能够从采样数据序列中提取不同时间尺度波动曲线,以达到时频分解的目的。文章对经验模态分解法的重大改进,主要体现在零平均线的求取上,它无需求上、下包络线,而直接把N点原始数据按时间尺度分段压缩,再用3次样条函数光滑插值到N点,并以此作零平均线,从而得出分层模态分解,改进了Harr小波分解。
經驗模態分解法( EMD變換),能夠從採樣數據序列中提取不同時間呎度波動麯線,以達到時頻分解的目的。文章對經驗模態分解法的重大改進,主要體現在零平均線的求取上,它無需求上、下包絡線,而直接把N點原始數據按時間呎度分段壓縮,再用3次樣條函數光滑插值到N點,併以此作零平均線,從而得齣分層模態分解,改進瞭Harr小波分解。
경험모태분해법( EMD변환),능구종채양수거서렬중제취불동시간척도파동곡선,이체도시빈분해적목적。문장대경험모태분해법적중대개진,주요체현재령평균선적구취상,타무수구상、하포락선,이직접파N점원시수거안시간척도분단압축,재용3차양조함수광활삽치도N점,병이차작령평균선,종이득출분층모태분해,개진료Harr소파분해。
Empirical mode decomposition method ( EMD transform ) can extract wave fluctuation at different time scales from sampled data sequences , therefore can achieve the purpose of time -frequency decomposition .This paper proposes a major improvement for EMD transform , which is mainly reflected in the calculation of the zero average line.The method has no demand for upper and lower envelope calculation .Instead , it piecewisely compresses the origi-nal N-point data at different time scales , and then uses cubic spline function to smoothly interpolate to N points .The result is set as zero average line , and by this way the hierarchical mode decomposition is achieved .This paper also im -proves the Harr wavelet decomposition .