Detection and identification of explosives and illicit drugs by terahertz spectroscopy technology

Terahertz(THz)radiation, which occupies a relatively unexplored portion of the electromagnetic spectrum between mid-infrared and microwave bands, offers innovative sensing and imaging technologies that can provide information unavailable through conventional methods such as microwave and X-ray techniques. Spectroscopy in the terahertz frequency range has demonstrated unique identification of both pure and military-grade explosives. Explosive and illicit drug materials have characteristic THz spectra, a fuzzy neural network for classifying explosives and illicit drugs based on different THz spectra was designed. The designed Classifier can make hard decision and soft decision for identifying 9 patterns of explosives and illicit drugs at the accuracy of 89%, The highly successful result of the experiments, coupled with availability of practical THz systems which operate outside the laboratory environment, indicate that THz technologies are promising for the identification of explosives and illicit drugs.