Design of W-band passive millimeter wave imaging system

A W-band passive imaging system based on focal plane array (FPA) is developed and experimented in this paper. The imager consists of a 500mm diameter parabolic reflector, and 16 feed-horns array, 16 channels FPA wideband radiometric receiver based on Direct-detection total power type, scanning mechanism, image processor and displayer. The arrangement of the feed-horns is well designed to sample the survey scene at Nyquist density in vertical direction. Its achieved angular resolution is 0.47° and the thermal sensitivity varies between 1.3 and 1.5K at integration time 2.5ms. By scanning in azimuthal direction, the system forms one frame of image with field of view (FOV) of about 60°H×8°V in 8 seconds.