Abstract
The presence of a reflecting boundary modifies the free‐field backscattering response of an object. Boundary reflections increase the number of available paths for scattered sound to return to a source‐receiver. In the present work, high‐frequency tank experiments on solid aluminum cylinders demonstrate a strong boundary related backscattering response that is present for a broad range of aspect angles. To study the effects of close proximity to a flat reflecting boundary, cylinders were suspended in water near the tank’s air‐water interface. Targets were insonified from below at grazing incidence. Monostatic measurements were made as the cylinders were rotated in a plane parallel to the boundary. Some aspects of this response could be understood by modeling the region of water bounded by the cylinder top and the air‐water interface as a quasi‐2‐D waveguide. Sound incident on this region of decreasing water thickness can be reflected as from a seamount. The backscattered amplitude is strongly affected by the threshold frequency for propagation in the gap between the cylinder and the adjacent flat surface. Experiments show that the behavior of this response, as a function of target depth and aspect angle, is in qualitative agreement with this waveguide model. [Work supported by ONR.]
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: 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.
