Velocity analysis of a lateral wave

Authors

DOI:

https://doi.org/10.5564/mgs.v28i56.2794

Keywords:

FDTD simulation, electromagnetic wave, CMP

Abstract

In practice, the reflected EM signal cannot be clearly observed in GPR data due to the high water content and other reasons. However, the antenna coupling signal through the ground interface is dominated in all the GPR measurements. This direct coupling signal that travels through the ground interface is called a lateral wave. The properties of the lateral wave directly depend on the subsurface properties, especially electrical parameters. We have numerically analyzed a lateral wave and its velocity. Subsequently, the relationship between lateral wave and dielectric permittivity was determined by polynomial regression. Analytically, it is challenging to analyze a lateral wave due to the parameters that can influence wave propagation. Antenna characteristics, surface roughness, etc need to be considered. Numerically, we designed a GPR system with a subsurface layer and observed a lateral wave. This numerical analysis can give a chance to use a lateral wave for near-surface soil water content. This analysis gives a more precise estimation of surface water content. Moreover, we analyze the antenna height effect that influences radar signals. We numerically observed that the GPR signal is highly affected by antenna height. The antenna height effect depended on the wavelength of the applied electromagnetic wave. By adjusting the antenna height, the unobservable GPR signal can be clearly detected.

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References

Annan, A.P. 1973. Radio Interferometry Depth Sounding: Part I -Theoretical Discussion. Geophysics, v. 38(3), p. 557-580. https://doi.org/10.1190/1.1440360

Bradford, J.H., Deeds, J.C. 2006. Ground-penetrating radar theory and application of thin-bed offset-dependent reflectivity. Geophysics, v. 71(3), K47. https://doi.org/10.1190/1.2194524

de Coster, A., Lambot, S. 2019. Full-Wave Removal of Internal Antenna Effects and Antenna-Medium Interactions for Improved Ground-Penetrating Radar Imaging. IEEE Transactions on Geoscience and Remote Sensing, v. 57(1), p. 93-103. https://doi.org/10.1109/TGRS.2018.2852486

Gerhards H., Wollschläger, U., Yu, Q., Schiwek, P., Pan, X., Roth, K. 2008. Average Soil-Water Content with Multichannel Ground-Penetrating Radar. Geophysics, v. 73(4), p. 15-23. https://doi.org/10.1190/1.2943669

King, R.W.P., Owens, M., Wu, T.T. 1992. Lateral Electromagnetic Waves. Theory and Applications to Communications, Geophysical Exploration, and Remote Sensing. 1st ed, New-York, Springer-Verlag, ISBN: 978-1-4613-9174-6

Sato, M., Takahashi, K., Asaya, Y., Iitsuka, Y. 2015. Radiation of electromagnetic wave from an antenna placed close to a boundary of materials, Simulation of GPR antenna. IEICE Technical Report, EMT2015-20, v. 115(141), p. 65-70.

Shavit, R., Rosen, E. 1995. Lateral wave contribution to the radiation from a dielectric half medium. IEEE Transactions on Antennas and Propagation, v. 43(7), p. 751-755. https://doi.org/10.1109/8.391154

Zou, L., Yi, L., Sato, M. 2020. On the Use of Lateral Wave for the Interlayer Debonding Detecting in an Asphalt Airport Pavement Using a Multistatic GPR System. IEEE Transactions on Geoscience and Remote Sensing, v. 58(6), p. 4215-4224. https://doi.org/10.1109/TGRS.2019.2961772

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Published

2023-06-09

How to Cite

Amarsaikhan, T., & Sato, M. (2023). Velocity analysis of a lateral wave. Mongolian Geoscientist, 28(56), 14–26. https://doi.org/10.5564/mgs.v28i56.2794

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