摘要
小波变换是一种具有一定时间和频率分辨率的分析方法。为了寻找更有效的去噪方法,对连续小波变换(CWT)、离散序列小波变换(DTWT)和正交小波变换(QWT)作了理论分析。结果表明:CWT对噪声具有良好的抑制作用;DTWT在通过域值处理的同时,也考虑了因噪声造成的某些信号细节的丢失;而QWT则能有效地提取淹没在噪声中的微弱信号。与传统的傅里叶变换(FT)相比较,具有显著的优点,值得关注。
The wavelet transform is a kind of multi-resolution method on finite time and frequency. In order to seek out de-noising method,this paper studied the continous wavelet transform (CWT),discrete wavelet transform (DTWT) and orthenormal wavelet transform (QWT) in theory and practice. The results showed that CWT has a good suppression function for noise. When it is going through the Valve Processing, DTWT also consider useless noise to produce some losses of particular signal; But QWT can effectively pick up the weak signal submerged in the noise. Compared with the Fourier transform, the wavelet has marked ad vantages, hence worthy of note.
出处
《浙江师范大学学报(自然科学版)》
CAS
2003年第4期345-349,共5页
Journal of Zhejiang Normal University:Natural Sciences
关键词
小波变换
去噪
域值
傅里叶变换
信号处理
电磁场
wavelet transform
de-noising
valve value
Fourier transform suppression