Articles | Volume 13, issue 1
https://doi.org/10.5194/gi-13-27-2024
https://doi.org/10.5194/gi-13-27-2024
Research article
 | 
13 Feb 2024
Research article |  | 13 Feb 2024

An optimized and hybrid gating scheme for the suppression of very low-frequency radios in transient electromagnetic systems

Smith Kashiram Khare, Paul McLachlan, Pradip Kumar Maurya, and Jakob Juul Larsen

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Cited articles

Auken, E., Boesen, T., and Christiansen, A. V.: Chapter Two – A Review of Airborne Electromagnetic Methods With Focus on Geotechnical and Hydrological Applications From 2007 to 2017, Adv. Geophys., 58, 47–93, https://doi.org/10.1016/bs.agph.2017.10.002, 2017. a
Auken, E., Foged, N., Larsen, J. J., Lassen, K. V. T., Maurya, P. K., Dath, S. M., and Eiskjær, T. T.: tTEM – A towed transient electromagnetic system for detailed 3D imaging of the top 70 m of the subsurface, Geophysics, 84, E13–E22, https://doi.org/10.1190/geo2018-0355.1, 2019. a, b, c
Chen, J., Jia, W., Zhang, Y., and Lin, J.: Integrated TEM and GPR Data Interpretation for High-Resolution Measurement of Urban Underground Space, IEEE T. Instrum. Meas., 71, 1–9, https://doi.org/10.1109/TIM.2021.3134995, 2022. a, b
Chen, S., Zhang, S., Zhu, J., and Luan, X.: Accurate Measurement of Characteristic Response for Unexploded Ordnance With Transient Electromagnetic System, IEEE T. Instrum. Meas., 69, 1728–1736, https://doi.org/10.1109/TIM.2019.2917236, 2020. a
Christiansen, A. V., Auken, E., and Sørensen, K.: The transient electromagnetic method, 179–226, Springer, https://doi.org/10.1007/978-3-540-88405-7_6, 2009. a
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Short summary
Data recorded with transient electromagnetics are typically gated to improve the signal-to-noise ratio. Gating corresponds to low-pass filtering of data with the shape of the gate giving the frequency response. We show that standard gate shapes can lead to significant correlation between gates caused by distortion from VLF radios. A multi-objective cost function is used to select optimum gate shapes with less influence from radio noise. Performance is demonstrated using synthetic and field data.