改进的基于频率顺序的小波包消噪方法  

An Improved Wavelet Packet Denoising Method Based on Frequency Order

作　　者：张孝强[1] 鲁怀伟[1] 

机构地区：[1]兰州交通大学数理学院,甘肃兰州730070

出　　处：《兰州文理学院学报（自然科学版）》2017年第6期64-68,共5页Journal of Lanzhou University of Arts and Science(Natural Sciences)

摘　　要：针对传统小波包消噪方法消噪效果不佳、精度不高的问题,提出了一种以小波包频率顺序为基础,结合小波包分解系数能量谱和新阈值函数的消噪方法.利用小波包分解系数能量谱实现了低频段和高频段的小波包分解系数的细化处理.通过插值得到的新阈值函数,不仅克服了传统软、硬阈值函数的缺点,实现了阈值的平滑过渡,还可以在软、硬阈值函数间进行灵活的转换.仿真结果表明,与传统小波包消噪方法相比,新方法有效提高了消噪精度,保留了信号在各个频段的细节信息,减少了信号的失真,具有更好的消噪效果.Aiming at the problem that the traditional wavelet packet denoising method has poor effect and low precision,a new method based on wavelet packet frequency sequence is proposed,which combines the wavelet packet decomposition coefficient energy spectrum and the new threshold function.For one thing,by using wavelet packet decomposition coefficient energy spectrum,the wavelet packet decomposition coefficients of the low frequency and high frequency segments are processed;For another,the new threshold function can not only overcome the shortcomings of the traditional soft and hard threshold function,achieve a smooth transition of the threshold,but also can be flexible in the soft and hard threshold function.The simulation results show that compared with the traditional wavelet denoising method,the new method can improve the accuracy of signal denoising,preserve the details of information in each frequency band and reduce signal distortion.On the whole,the new method has better denoising effect.

关 键 词：小波包分析 能量谱 频率顺序 HERMITE插值 平滑度 

分 类 号：TN911.7[电子电信—通信与信息系统]