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Resolution improving filter for time-reversal (TR) with a switching TR mirror in a halfspace
Heedong Goh1, Seungbum Koo2, Loukas F Kallivokas3
1Department of Civil, Architectural and Environmental Engineering, The University of Texas at Austin, Austin, Texas 78712, USA.
The Journal of the Acoustical Society of America
|May 4, 2019
Summary
This study introduces a data filter to improve wave energy focusing with switching time-reversal (TR) mirrors for subsurface targets, enhancing resolution in practical geophysics and medicine applications.
Area of Science:
- Geophysics
- Wave physics
- Signal processing
Background:
- Time-reversal (TR) mirrors enable efficient wave focusing for subsurface targets.
- Practical limitations like unbounded media and switching TR mirrors degrade focusing resolution.
- Applications span geophysics, hydro-geology, environmental engineering, and therapeutic medicine.
Purpose of the Study:
- To address the resolution degradation issue caused by switching time-reversal mirrors.
- To develop a data filter that overcomes the shortcomings of switching TR mirrors.
- To enhance wave energy focusing for subsurface targets in real-world scenarios.
Main Methods:
- Development of a novel data filter designed for switching time-reversal systems.
- Analysis of wave propagation and focusing in unbounded media.
- Numerical simulations to demonstrate the filter's effectiveness.
Main Results:
- The developed data filter significantly improves focusing resolution at subsurface targets.
- The filter effectively compensates for the limitations imposed by switching TR mirrors.
- Numerical examples validate the enhanced focusing capabilities.
Conclusions:
- The proposed data filter is a viable solution for improving wave energy focusing with switching TR mirrors.
- This method enhances the practical applicability of time-reversal techniques in various scientific and engineering fields.
- Further research can explore advanced filter designs and applications.
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