多重自相关在微弱低频电磁信号检测中的应用

摘要

Low-frequency electro-magnetic signal is very important in the underground detection of the electrical structure. The signal can be attenuated after a long distances transmission, and it may be submersed by strong noise. Multi-layer autocorrelation is used to detect electromagnetic signal of weak low frequency in this paper, and compared with adaptive filtering and discrete wavelet transform. Matlab is used to make modeling and simulation and the results are compared with each means. Simulation results show that multi-layer autocorrelation can be smooth noise and extract useful signal effectively, and is better than others in majority aspects.%低频电磁信号在地下电性结构探测中具有重要作用,经过长距离传播,信号衰减,可能被淹没于噪声中.利用多重自相关检测方法,对微弱低频电磁信号进行检测,并与自适应滤波法和离散小波变换法进行对比.利用Matlab对3种算法进行仿真研究.结果表明,多重自相关法能更好抑制噪声,有效检测微弱信号,检测性能优于小波变换法和自适应滤波法.