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Bistatic scattering from submerged unexploded ordnance lying on a sediment
J A Bucaro1, H Simpson, L Kraus
1Naval Research Laboratory, Washington, DC 20375, USA. bucaro@pa.nrl.navy.mil
The Journal of the Acoustical Society of America
|November 10, 2009
Summary
Bistatic target strength measurements for submerged unexploded ordnance (UXO) reveal strong forward and backscattered echoes. This bistatic data offers comparable or higher broadband target strength levels than monostatic measurements, aiding UXO detection.
Area of Science:
- Underwater acoustics
- Geophysics
- Radar engineering
Background:
- Previous studies measured monostatic target strengths of submerged unexploded ordnance (UXO).
- Understanding target strength is crucial for effective underwater object detection.
Purpose of the Study:
- To measure broadband bistatic target strengths (TSs) of two submerged UXO targets.
- To compare bistatic TS with monostatic measurements and theoretical predictions.
Main Methods:
- Measurements were conducted in the NRL sediment pool facility with targets proud of the sediment.
- Broadband bistatic TS was measured for 0 and 90-degree incident source directions.
- Both backscattered and forward scattered echoes were recorded over 360 degrees.
Main Results:
- Both the 5 in. rocket and 155 mm projectile exhibited strong backscattered and forward scattered highlights.
- Bistatic TS levels agreed well with predictions based on scattering models.
- Proudly placed targets showed comparable or higher broadband TS than free-field monostatic measurements.
Conclusions:
- Bistatic echo information can significantly enhance submerged UXO detection capabilities.
- Forward scattered responses provide valuable data for UXO identification.
- Bistatic measurements offer a promising approach for improving underwater acoustic sensing.
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