基于提升小波的试井信号降噪研究

在油气井试井数据传输中,由于接收信号被噪声污染,从而影响了通信可靠性。小波变换因具有独特的时频多尺度分析特性而应用于信号降噪，但一代小波运算量大。采用运算量小的提升小波对试井信号降噪，给出了db2提升小波降噪的具体结构，在此基础上，与离散傅里叶滤波和匹配滤波两种降噪方法进行了比较。仿真结果表明，采用db2提升小波降噪效果明显，峰值信噪比高，且运算量小，有利于硬件电路的实现。

Signal de-noising by lifting wavelet in well test

The reliability of communication is reduced because the signal is contaminated by a strong noise in oil or gas well data communication. Compared with the Fourier transform, Wavelet transform can give a better signal representation using Multiresolution analysis, with balanced resolution at any time and frequency. However, the operation amount of the traditional wavelet is large, so the lifting wavelet is used. The db2 lifting wavelet structure is derived. The test results show that, compared with the discrete cosine transform filter and matching filter, db2 lifting wavelet de noising has obvious effect, the highest ratio of peak signal to noise, and the smallest amount of computation, the ease of hardware implementation.