Abstract
We present the general concept and results of a pilot study on land mine detection based on the application of Time Reverse Acoustics (TRA). Applying TRA is extremely effective at focusing seismic waves in time and space, significantly improving detection capabilities using both linear and nonlinear wave methods. The feasibility of the system was explored in the laboratory and in small scale field experiments. The system included a multi-channel TRA electronic unit developed at Artann, five speakers for seismic-wave excitation and noncontact (laser vibrometer) or contact (accelerometer) devices for measurements of the surface vibration. Experiments demonstrated the high focusing ability of the TRA system. We observed excitation of highly focused seismic waves in an area with dimensions of the order of one wavelength. In the presence of a buried mock mine, the method led to an increase in the surface vibration amplitude and to significant nonlinear distortion of the TRA focused signal. Localization via TRA depends on the frequency of excitation, the depth of the buried mine, and the form and size of a mine mock. The nonlinear acoustic effect - higher harmonic generation - provides higher contrast for the mock-mine signal-response than for the surrounding medium. We also successfully tested an inversion method of the nonlinear TRA measurements earlier developed for medical ultrasound applications.
Original language | English |
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Article number | 144 |
Pages (from-to) | 706-716 |
Number of pages | 11 |
Journal | Proceedings of SPIE - The International Society for Optical Engineering |
Volume | 5794 |
Issue number | PART II |
DOIs | |
State | Published - 2005 |
Event | Detection and Remediation Technologies for Mines and Minelike Targets X - Orlando, FL, United States Duration: 28 Mar 2005 → 1 Apr 2005 |
Keywords
- Land mine detection
- Nonlinear acoustics
- Time Reversal Acoustics