September 1, 2001
Journal Article

Three-Dimensional Millimeter-wave Imaging for Concealed Weapon Detection


Millimeter-wave imaging techniques and systems have been developed at the Pacific Northwest National Laboratory (PNNL) for the detection of concealed weapons and contraband at airports and other secure locations. These techniques were derived from microwave holography techniques which utilize phase and amplitude information recorded over a two-dimensional aperture to reconstruct a focused image of the target. Millimeter-wave imaging is well suited to the detection of concealed weapons or other contraband carried on personnel since millimeter-waves are non-ionizing, readily penetrate common clothing material, and are reflected from the human body and any concealed items. In this paper, a wide-bandwidth, three-dimensional, holographic microwave imaging technique is described. Practical weapon detection systems for airport, or other high-throughput applications, require high-speed scanning on the order of 3 to 10 seconds. To achieve this goal, a prototype imaging system utilizing a 27-33 GHz linear sequentially switched array and a high-speed linear scanner has been developed and tested. This system is described in detail along with numerous imaging results.

Revised: April 8, 2002 | Published: September 1, 2001


Sheen D.M., D.L. McMakin, and T.E. Hall. 2001. Three-Dimensional Millimeter-wave Imaging for Concealed Weapon Detection. IEEE Transactions on Microwave Theory and Technique 49, no. 9:1581-1592. PNNL-SA-33821.