Effective information extraction from high-order pseudo-random electromagnetic signals in urban environments:A case study of a rail transit engineering area in Jinan City, China
MA Zhen-Bo1(), ZHOU Chang-Yu2, RUAN Jin-Ping3, ZHANG Wen-Yan4
1. Henan Academy of Geology, Zhengzhou 450016, China 2. School of Science and Engineering, The Chinese University of Hong Kong, Shenzhen 518000, China 3. Institute of Geotechnical and Underground Engineering, Shandong University, Jinan 250000, China 4. Shandong Research Institute of Coal Geological Planning and Prospecting, Jinan 250000, China
The spectra of high-order pseudo-random electromagnetic signals encompass all the frequencies required for exploration engineering, it has the characteristics of enhancing work efficiency and strong anti-interference capability, and has been applied in electromagnetic exploration in urban environments. This study extracted effective information from high-order pseudo-random signals in the electromagnetic survey conducted in areas with strong powerline interference within the special exploration area of the Phase I engineering of the Jinan Urban Rail Transit Line 8. To efficiently extract high-quality effective information, an envelope assessment algorithm was combined with high-order pseudo-random signals. Specifically, the actual signal interference was accurately estimated by analyzing the spectral envelope values. This allows for screening received signals, thus further mitigating the impacts of powerline interference and its harmonics. As a result, more effective frequency and geoelectric information were obtained, providing abundant effective electromagnetic data for subsequent inversion and interpretation. The novel method serves as a technique for effective information extraction for future electromagnetic sounding in a complex urban environment.
马振波, 周长宇, 阮进平, 张文艳. 城市环境下的高阶伪随机电磁信号有效信息提取——以济南市某轨道交通工程区为例[J]. 物探与化探, 2024, 48(6): 1709-1719.
MA Zhen-Bo, ZHOU Chang-Yu, RUAN Jin-Ping, ZHANG Wen-Yan. Effective information extraction from high-order pseudo-random electromagnetic signals in urban environments:A case study of a rail transit engineering area in Jinan City, China. Geophysical and Geochemical Exploration, 2024, 48(6): 1709-1719.
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