摘 要：針對(duì)經(jīng)驗(yàn)?zāi)B(tài)分解（EMD）在分解信號(hào)時(shí)存在的端點(diǎn)效應(yīng)問(wèn)題，為抑制端點(diǎn)效應(yīng)對(duì)信號(hào)分析帶來(lái)的影響，進(jìn)一步提高EMD分解準(zhǔn)確度，提出基于基因表達(dá)式編程（GEP）的EMD改進(jìn)算法。通過(guò)仿真實(shí)驗(yàn)與鏡像延拓等其他3種常用端點(diǎn)效應(yīng)抑制方法作對(duì)比，并計(jì)算評(píng)價(jià)端點(diǎn)效應(yīng)的兩個(gè)指標(biāo)，最后，通過(guò)這4種方法分別測(cè)量出原始信號(hào)的瞬時(shí)頻率以作驗(yàn)證。仿真結(jié)果表明：基于GEP的EMD改進(jìn)算法在分解信號(hào)后各分量?jī)啥税l(fā)散程度最小，評(píng)價(jià)指標(biāo)也均優(yōu)于其他3種傳統(tǒng)的改進(jìn)方法，且更加準(zhǔn)確地測(cè)量出原始信號(hào)的瞬時(shí)頻率。證明該改進(jìn)算法能更有效地抑制EMD端點(diǎn)效應(yīng)，具有更高的應(yīng)用價(jià)值。
關(guān)鍵詞：經(jīng)驗(yàn)?zāi)B(tài)分解；基因表達(dá)式編程；端點(diǎn)效應(yīng)；瞬時(shí)頻率
文獻(xiàn)標(biāo)志碼：A 文章編號(hào)：1674-5124（2015）12-0032-04
GEP-based suppression of end effect in EMD
YANG Bo， LI Shiping
（The Second Artillery Engineering College，Xi’an 710025，China）
Abstract: An improved algorithm of empirical mode decomposition （EMD） based on gene expression programming（GEP） was proposed in this paper to solve the end effect existing in the signal decomposition process of EMD and to restrain the strong impact brought of end effect on signal analysis to improve further the decomposition precision of EMD. After comparing it with three other commonly-used methods namely simulation and experiment and mirror extension， the two indicators of end effect were calculated and evaluated and the instantaneous frequency of original signals was measured and verified ultimately. The simulation results indicate that the divergence degree at both ends of each component is the lowest， the evaluation indicators are more superior， and the instantaneous frequency of the original signal measured is more precise compared with the three traditional improved methods. It has proven that this improved algorithm is more precise and practical in restraining the end effect.
Keywords: EMD； GEP； end effect； instantaneous frequency
