Time resolved synthetic aperture terahertz impulse imaging

Abstract

Using a well characterized terahertz (THz) impulse ranging system we demonstrate broad bandwidth imaging at THz frequencies using an inverse synthetic aperture deconvolution technique. The system demonstrates millimeter and submillimeter resolutions along the cross range and range axes, respectively. The range resolution, determined by the THz pulse bandwidth is 0.12 mm, while the cross range resolution is 1.2 mm; both resolutions agree well with theoretical predictions. Through imaging of cylindrical targets we demonstrate quantitative measurement of target position in the image plane within the experimental error of 0.2 mm. Imaging of geometrically scaled complex targets is demonstrated for a 1:2400 scale model ship (1 mm=24 m) corresponding to a full scale frequency bandwidth of 83–625 MHz at a distance of 840 m.