摘要
对于非平稳信号,小波多尺度分解是一种有效的信号去噪方法。介绍了阈值计算的Stein的无偏风险估计子(SURE)阈值、多分辨率SURE阈值和平移不变阈值,以及硬取阈值、软取阈值估计子,同时提出了一种新的小波消噪阈值选取方法,提出了相关参数的确定原则;并与硬取阈值、软取阈值进行比较,仿真结果表明,消噪效果有明显的改观。
It is an effective method to reduce the noises by wavelet multi-scah decomposition in nonstationary signals.Threshold calculation methods,such as SURE,Multi-resolution SURE,and Translstion-Invariant thresholding, are introduced. Besides, estimate arithmetic operators,inchding hard-thresholding, soft-thresholding,are presented.In addition,a new means of threshold selections for wavelet denoising is introduced, and the principles of deciding corresponding parameters are put forward.Further more,the comparison of it with hard-thresholding and soft-thresholding are carried out. The simulations are conducted about he applications of them in digital signal denoising,and the results show the denoising effects are improved.
出处
《中国测试技术》
2006年第4期28-30,共3页
CHINA MEASUREMENT & TESTING TECHNOLOGY
关键词
小波分析
硬取阈值
软取阈值
多分辨率SURE
平移不变
信号去噪
Wavelet analysis
Hard threshold
Soft threshold
Multi-resolution SURE
Translation invariant
Signal denoising
