The use of a waveguide expansion to model landmine detection using acoustic to seismic coupling

Abstract

The use of a waveguide of sufficiently large radius to simplify the modeling of the infinite space response of a buried landmine to airborne sound has been investigated. It was previously determined that if the ground is modeled as an effective fluid, an efficient and rapidly converging algorithm can be obtained. The effective fluid has been replaced with an elastic solid. For such a model, this technique fails to converge sufficiently rapidly to the infinite space limit. The surface wave supported by the shear sector gets excited by the landmine. The decay of this surface wave with distance is too slow, forcing one to use a waveguide of a prohibitively large radius. In conclusion, this technique at best gives qualitative results. [Work sponsored by the U.S. Army Communications–Electronics Command, Night Vision and Electronics Sensors Directorate.]