基于相关自适应器的EM-MWD信号检测系统设计

经EM-MWD(electromagnetic method measurement while drilling)电磁通道传输至地表的信号很微弱并且极易受到白噪声、奇异噪声、工频噪声及其谐波等干扰,导致信号特征参数提取的准确度降低,为了解决这一难题,通过对电磁波传输信道的研究,根据接收初始信号强度以及自适应检测和相关检测的特点,研究并设计了相关自适应器,并基于此设计了电磁随钻地表信号检测系统。然后用Hilbert变换求信号包络,完成了数据拟合和残差分析,并计算了信噪比、均方根误差和误码率,最后做了实验。仿真和实验结果表明,利用该检测系统,能够提高信号特征参数的准确度,达到有效降噪目的,对后续分析和研究提供了保证。

Design of EM-MWD signal detection system based on correlation and adaptive filter

The signal transmitted to ground surface through electromagnetic method measurement while drilling(EM-MWD) signal channel is very weak and suffers from the interference of white noise,pulse noise,power frequency noise and its harmonics,which results in the accuracy reduction of characteristic parameter extraction.In order to solve this problem,based on studying the electromagnetic wave transmission channel,according to the strength of received signal and characteristics of correlation and adaptive detection,the correlation and adaptive filter is studied and a detection system of EM-MWD is designed.Then the signal envelope is obtained using Hilbert transform,the data fitting and residual analysis are completed;and the root mean square error,signal to noise ratio and bit error rate are calculated.Experiment was carried out.Simulation and experiment results show that with this detection system,the accuracy of the signal characteristic parameters is improved;the purpose of effectively reducing noise is achieved,which provides a basis for the follow-up analysis and research.