Abstract
In the Arctic and Antarctic scientific expeditions, ice-penetrating radar is an effective method for studying the bedrock under the ice sheet and ice information within the ice sheet. Because of the low conductivity of ice and the relatively uniform composition of ice sheets in the polar regions, ice-penetrating radar is able to obtain deeper and more abundant data than other geophysical methods. However, it is still necessary to suppress the noise in radar data to obtain more accurate and plentiful effective information. In this paper, the entirely non-recursive Variational Mode Decomposition (VMD) is applied to the data noise reduction of ice-penetrating radar. VMD is a decomposition method of adaptive and quasi-orthogonal signals, which decomposes airborne radar data into multiple frequency-limited quasi-orthogonal Intrinsic Mode Functions (IMFs). The IMFs containing noise are then removed according to the information distribution in the IMF’s components and the remaining IMFs are reconstructed. This paper employs this method to process the real ice-penetrating radar data, which effectively eliminates the interference noise in the data, improves the signal-to-noise ratio and obtains the clearer inner layer structure of ice. It is verified that the method can be applied to the noise reduction processing of polar ice-penetrating radar data very well, which provides a better basis for data interpretation. At last, we present fine ice structure within the ice sheet based on VMD denoised radar profile.
Highlights
The Antarctic ice sheet preserves the ice depositional sequence and contains rich information about the paleoenvironment
The results obtained show that Variational Mode Decomposition (VMD) is an able method in data processing of ice-penetrating radar data
The data below the ice surface was used as test data (Figure 9a) and was processed by VMD
Summary
The Antarctic ice sheet preserves the ice depositional sequence and contains rich information about the paleoenvironment. Due to the low conductivity of ice, distinct layering and homogeneity of ice sheets, compared with other geophysical methods, the ice-penetrating radar has higher penetration capability and better internal layer resolution It characterizes numerous information and is highly efficient. In practice, the signals to be processed are often nonlinear and non-stationary (i.e., their parameters or distribution law changes with time), and they usually appear as a combination of harmonic components in the frequency domain. The ice sheet permittivity model and conductivity model are established to perform the forward simulation in order to obtain the simulated radar data, and the data is decomposed using the VMD method to observe the noise reduction effect of the method. The results obtained show that VMD is an able method in data processing of ice-penetrating radar data
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.