井下套管声波通讯的小波去噪  

The wavelet denoising in downhole casing acoustic communication.

作　　者：景宇富[1] 程为彬[1] 郭颖娜[1] 霍爱清[1] 

机构地区：[1]西安石油大学电子工程学院

出　　处：《石油机械》2011年第6期33-35,93,共3页China Petroleum Machinery

基　　金：陕西省科学技术研究发展计划项目"旋转导向钻井地面下行通讯导流关键技术研究"(2010k07-09);中国石油天然气集团公司中青年创新基金项目"智能旋转垂直钻井工具稳定平台关键控制技术研究"(07E1014);陕西省教育厅专项科研计划项目"旋转导向钻井电磁转矩控制理论和技术研究"(09JK687)

摘　　要：井下套管声波通讯中,接收信号掺杂着很多高次谐波和多种噪声,声波衰减时间长,导致井下套管声波通讯抗干扰性差,通讯速率低。模拟去噪电路滤波的阈值受到电子元件参数值的限制,滤波频率单一。通过分析声波在套管中的传播特性,建立数学模型,提出利用小波分析设置信号阈值去噪法,达到消噪、缩短信号衰减周期和提高信号传输率的目的。通过仿真波形和试验波形的对比,验证了该方法的可行性。In downhole casing acoustic communication the received signals are mixed with many high harmonics and many kinds of noises,and the long period of acoustic attenuation leads to poor noise immunity and low communication rate.The simulation of the threshold of denoise circuit filtering is restricted by the parametric values of electronic components with single filtering frequency.By analyzing the transmission characteristics of acoustic waves in casing,the mathematical model was established and the denoise method of establishing signal threshold through wavelet analysis was formulated so as to achieve the purpose of denoising,shortening the signal attenuation cycle and improving signal transmission rate.Through a comparison of simulation waveform and experimental waveform,the reliability of the method was verified.

关 键 词：套管 声波 阈值去噪 小波分析 仿真 

分 类 号：TE2[石油与天然气工程—油气井工程]