A Novel Inverse SAR Microwave Imaging Technique using Ultra Wideband Pulsed Radar

Impulse Radar (Ultra-Wideband) based imaging technique is an attractive proposition for detecting concealed objects. It is envisaged that in an ideal industrial deployment scenario, the target object will be in motion with respect to a static radar. This is akin to Inverse Synthetic Aperture Radar (ISAR) imaging. In this paper, we demonstrate a novel motion-induced radar imaging technique, where the object under study undergoes a circular translation motion on a rotating platform. A modified delay-and-sum (DAS) algorithm is built by incorporating virtual antenna array to estimate the shape of the object and its radial and angular displacement with respect to a fixed reference point. From the reconstructed images, it is seen that the radial displacement as well as the angular locations of the object have been successfully identified. We demonstrate the detection of objects of very small radar cross section, given as
$circum\ ference/\lambda\approx 1.5$
. The work will be further extended in future to image non-metallic objects inside sealed package.