东南大学学报（自然科学版）2012，Vol.42Issue(z2)：320-325,6.DOI:10.3969/j.issn.1001-0505.2012.S2.018
一种改进的最小方差自适应时延估计算法在碰摩声发射定位中的应用
Application of improved LMSTDE algorithm in location ofrub-impact acoustic emission
摘要
Abstract
Due to difficulties of source localization of rub-impact acoustic emission influenced by attenuation and strong noise in propagation process, the least mean square adaptive time delay estimate (LMSTDE) algorithm is introduced. The traditional algorithm is improved, and an improved LMSTDE algorithm which estimates the attenuation coefficient and time delay simultaneously and itera-tively is proposed. The improved algorithm adds an attenuation coefficient estimator which estimates the time delay and attenuation coefficient simultaneously and iteratively according to the error between estimated value and reference value. In order to accelerate the convergence speed, variable step size processing is used in the improved LMSTDE algorithm. When the error between the estimated value and the reference value is relatively large, the gradient of the error is used to adjust the step size; when the error is relatively small, the error signal is weighted by the forgetting factor to adjust the step size. Theoretical analysis and experimental results show that the improved LMSTDE algorithm can converge to the true value. Compared with traditional LMSTDE algorithm, the improved algorithm has better performance when the SNR is low and faster convergence speed.关键词
声发射/碰摩/定位/最小方差自适应时延估计/变步长Key words
acoustic emission/ rub-impact/ location/ least mean square adaptive time delay estimate/ variable step size分类
机械制造引用本文复制引用
邓艾东,童航,秦康,曹浩,颜喜..一种改进的最小方差自适应时延估计算法在碰摩声发射定位中的应用[J].东南大学学报（自然科学版）,2012,42(z2):320-325,6.基金项目
国家自然科学基金资助项目(51075068). （51075068）
