ACOUSTIC TOMOGRAPHY AND STANDING WAVE RESONANCE FOR CARGO SCREENING

This feasibility study will investigate two separate but complementary acoustic techniques for the screening of commercial cargoes. This involves sending acoustic chirp signals through cargo, whilst still on the lorry, as it passes slowly passed a measurment station at a port or other location. The two techniques would be used to image internal contents, and to identify certain objects via resonances. A specific aim is to generate a 3-dimensional representation of the internal contents of a cargo and to virtually unpack its contents via one technique - and to very quickly detect concealed voids and cavities that may contain persons and/or contraband via the second technique. These two techniques are complementary and could be used separately or simultaneously upon the same target cargo. One major advantage that these methods offer over existing technology is that comparatively they would be extremely cheap to manufacture and (very importantly when considering the nature and location of their deployment) is that they are completely safe and present little hazard to human health and are completely non-radiological and non-ionising.Another important advantage is that owing to the differences in the speed of sound through different solid metals, it would be relatively simple to readily characterise and distinguish nuclear material from other dense metals in the instance of their camouflaged transportation in clandestine shipments.