Advances in millimeter-wave imaging technology for enhanced vision systems

Trex Enterprises is developing a 2/sup nd/ generation passive millimeter wave imaging system which operates in real time with a 20/spl times/30 degree field of view and a 2 K temperature sensitivity. This system is based on a pupil-plane aperture architecture. A pupil-plane architecture allows for a lower system volume and reduced number of receivers compared to focal plane systems. The system has low noise W-band amplifiers, a flat panel dielectric antenna, high sensitivity diodes and will serve as the basis for a commercially available system. Millimeter wave imaging provides enhanced vision capabilities to pilots, allowing them to see through fog and smoke and aiding in navigation, landing, and taxiing in low-visibility situations. Unlike radar, passive millimeter wave imaging provides the pilot with a display based on angle-angle data rather than range-angle data which must be interpreted into an angle-angle display. The passive system avoids problems with multi-path reflections that can create problems for active systems in close proximity to the ground. The fact that the sensor does not emit also makes it useful for military applications where the pilot wishes to avoid detection.