INFRARED AND MILLIMETER-WAVE SENSORS FOR MILITARY SPECIAL OPERATIONS AND LAW-ENFORCEMENT APPLICATIONS

We consider the application of infrared and millimeter-wave sensors, d eveloped for the most part during the Cold War, to the solution of pro blems encountered by military special operations units and law enforce ment personnel. These problems include detection of weapons concealed beneath clothing, through-the-wall surveillance, and wide-area surveil lance under poor lighting conditions. Key sensors used in these applic ations are infrared cameras, millimeter-wave passive and active camera s, and millimeter-wave real-aperture and holographic radars. This pape r discusses each type of sensor, describes its operation, and gives an example of its output, except in those cases where the device is earl y in its development phase and thus no outputs are available. All of t hese sensors form images, but the images are of varying quality. We co nclude with a brief discussion of methods of using multiple sensors to improve performance.