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Portable Concealed Weapon Detection Using Millimeter Wave FMCW Radar Imaging

NCJ Number
189918
Author(s)
Yu-Wen Chang; Michael Johnson
Date Published
August 2001
Length
27 pages
Annotation
This report describes the development and performance of a fast image scanning 94GHz radar system that is suitable for portable operation and remote viewing of radar data for the unobtrusive detection of concealed weapons on persons or in abandoned bags.
Abstract
This system includes a novel fast image-scanning antenna that allows for the acquisition of medium resolution three dimensional millimeter wave images of stationary targets with frame times on the order of 1 second. The three-dimensional radar data allow for potential isolation of concealed weapons from body and environmental clutter such as nearby furniture or other people. The radar is an active system different from the millimeter wave passive imaging system that depends on millimeter wave emission/reflection contrast between the weapon and the body/clothing; therefore, the radar returned image data are the same whether indoors or outdoors. The 94 GHz radar-emitted power of approximately 1mW is low and poses no health concerns for operator or targets. The low power operation is still sufficient to penetrate heavy clothing or material. Small system size allows for easy transport and rapid deployment of the system as well as an easy migration path to future hand-held systems with a special image scan technique. A much faster scanning antenna and data acquisition system is deemed feasible for hand-held concealed weapon detection as a result of this research. 15 figures, 1 table, and 1 references