Chapter 9 - Detection of explosives by millimeter-wave imaging

Abstract

This Chapter discusses about Millimeter-wave imaging, which has emerged as an effective method for screening people for nonmetallic weapons including explosives. Millimeter waves are effective for personnel screening because the waves pass through common clothing materials and are reflected by the human body. Completely passive imaging systems have also been developed that rely on the natural thermal emission of millimeter waves from the body and concealed objects. Active and passive imaging systems have been developed by several research groups, with several commercial imaging sensors becoming available recently. Additional complementary systems are needed t to detect nonmetallic concealed items carried by personnel. Threats in the current environment include explosives, metallic and nonmetallic handguns, and edged weapons, as well as other tools and devices that may be incorporated into weapons. Widely implemented technologies, such as metal detectors and baggage X-ray systems, are important screening tools but will need to be augmented with new system technologies to detect the wide variety of current and future threats. Active and passive millimeter-wave imaging systems are expected to play an important role in these future explosive detection and security screening scenarios.