A real-time wide field of view passive millimeter-wave imaging camera

With the current upsurge in domestic terrorism, suicide bombings and the like, there is an increased interest in high technology sensors that can provide true stand-off detection of concealed articles such as guns and, in particular, explosives in both controlled and uncontrolled areas. The camera discussed in this paper is based upon passive millimeter-wave imaging (75.5-93.5 GHz) and is intrinsically safe as it uses only the natural thermal (blackbody) emissions from living beings and inanimate objects to form images with. The camera consists of four subsystems which are interfaced to complete the final camera. The subsystems are Trex's patented flat panel frequency scanned phased array antenna, a front end receiver, and phase and frequency processors to convert the antenna output (in phase and frequency space) into image space and in doing so form a readily recognizable image. The phase and frequency processors are based upon variants of a Rotman lens.