Affiliations: [a] Department of Electrical and Computer Engineering,
Michigan State University, East Lansing, MI 48824, USA
Correspondence:
[*]
Corresponding author: Kavitha Arunachalam, 2120 Engineering
Building, Department of Electrical and Computer Engineering, Michigan State
University, East Lansing, MI 48824, USA. Tel.: +1 517 432 1794; Fax: +1 517 353
1980; E-mail: kavithaa@egr.msu.edu
Abstract: Non-intrusive inspection (NII) systems with high throughput are
required for screening baggage, vehicles and cargo at ports of entry. Of the
existing NII techniques, systems employing X-rays have undergone rapid
evolution. Though well established, the probability of detecting contraband
goods in the radiographic image obtained using conventional high energy X-ray
systems depends on operator skill and orientation of the contraband material
inside the container. Alternative techniques employing back and forward
scattered X-rays operating at dual energy can only broadly classify objects
containing contraband material and cannot be used to uniquely locate the
contraband good. Limitations of X-ray radiography and scattererd imaging
systems could be resolved using 2D tomography systems. But, the complexities
associated with practical implementation of an X-ray CT system for screening
baggage, vehicles and cargo is far from realization. This paper presents an
X-ray imaging technique capable of providing 2D tomograms using limited-view
projections as an ideal compromise for detecting packaged, vehicle-borne and
human-borne explosives, weapons and contraband goods. Numerical simulations of
the proposed system employing L-shaped detectors and iterative reconstruction
algorithms indicate the feasibility of an alternate security screening system
to detect and uniquely locate explosives and contraband goods concealed in
cargo, baggage and vehicles.
