小波方法在油井液面检测中的应用

油井液面回波检测是石油探测的重要内容，它决定后续石油开采的成功与否。由于信号幅值小，干扰多，因而采用常规时、频域滤波方法往往不能收到良好的效果。针对这一问题，本文利用信号和干扰在小波变换下的不同变化特性及小波变换的变焦特性设计了小波去噪算法，并根据实际要求选定了小波基和分解尺度，给出了使用小波去噪方法前后的实际结果。对这些结果进行的分析比较表明，小波方法在大幅提高信噪比的同时，也保持了信号的位置信息，因而适合此类信号检测问题。

Application of Wavelet Based Method to Level Detection of Oil Wells

Level detection of oil wells is a key problem in petroleum prospecting, on which the subsequent recovery largely depends. However, because the signal is weak and disturbance is wide spread, conventional time frequency methods are of little effect. For this reason, a wavelet based denoising algorithm is designed in this article, which exploits the zooming behavior of wavelet transform and different changing trends between signal and disturbance in the wavelet transform. Proper wavelet bases and decomposing scales are chosen on actual request, along with comparison plots of original signal and denoised signal. Analysis on these results shows that the wavelet based method increases the SNR greatly, and at the same time keeps the position information of the detected signal. Therefore, it is suitable for signal detection problems of this kind.