双自适应提升方法用于洞壁加速度信号消噪  

Wall acceleration signal-denoising via dual-adaptive lifting scheme

作　　者：孙轶[1] 张培仁[1] 杨自友[2] 

机构地区：[1]中国科学技术大学自动化系,合肥230027 [2]中国科学技术大学近代力学系,合肥230027

出　　处：《振动与冲击》2009年第1期14-17,共4页Journal of Vibration and Shock

摘　　要：爆炸应力波对岩土洞壁所产生的加速度随着能量和时间的变化表现出非平稳的特性。由于加速度传感器的内阻高、输出信号小,容易受到环境噪声的影响,实测加速度曲线中存在大量的噪声信号。文中采用一种双自适应提升的小波变换方法对加速度信号进行消噪处理,在提升过程中采用自适应的方法设计更新算子和预测算子,并采用半软阈值法消噪。实验结果表明,双自适应提升小波变换结合半软阈值消噪方法与传统小波变换消噪方法相比,消噪后加速度信号的信噪比(SNR)有所提高,并且保留了突变信号部分的信息量,基于提升方法也大大提高了算法灵活性,缩短计算时间。With change of energy and time,the acceleration generated by explosive stress wave on a wall demonstrates non-stationary characteristics.There is a large number of noise signals in the measured acceleration curve,due to the extremely high sensitivity of the acceleration sensor detection.An adaptive lifting wavelet transformation method for acceleration signal-denoising was developed here.In the lifting process,the adaptive method was used to design an updating operator and a predicting operator,and a half soft-threshold was exploited for denoising.The experimental results reveal that,compared with the traditional wavelet transformation method for denoising,the adaptive lifting wavelet transformation combined with the half soft-thresholding method for signal-denoising exhibits several advantages.After denoising,the signal to noise radio(SNR) of the acceleration signal was improved to some extent,the information of the sudden change signal was retained.Via the lifting scheme,the flexibility of the algorithm was enhanced substantially and the computation time was reduced as well.

关 键 词：提升方法 自适应 加速度信号 消噪 信噪比 

分 类 号：TU457[建筑科学—岩土工程]