DESIGN AND DEVELOPMENT OF A SYNTHETIC APERTURE RADAR VOLUMETRIC IMAGING SYSTEM

Abstract

Synthetic aperture radar (SAR) is a widely used technique for creating high-resolution images of scenes. While SAR is primarily used for 2-D imaging, there is growing interest in developing SAR imaging for 3-D reconstructions of objects and target scenes. This can be accomplished by adding a vertical motion dimension to the synthetic aperture setup, enabling elevation compression alongside azimuth compression. By employing two orthogonal linear actuators, high-resolution imaging in all three dimensions becomes possible. This thesis describes the design and development of a track-mounted SAR system leveraging a low-cost wideband automotive radar to form high-resolution volumetric images of a near-range target scene. The automotive radar industry has transitioned to operating in the 76 to 81 GHz band, which is ideal for applications requiring short-range target detection. Therefore, this system operates at 77 GHz, enabling precise object location in 3-D space without the drawbacks associated with large bandwidths over long distances. The setup incorporates an automotive radar module, an in-house signal processing toolkit, and a control system designed to autonomously and accurately position the radar evaluation module for sending and receiving radar pulses. These pulses and their corresponding positions are processed using the backprojection algorithm to generate a volumetric image of the target scene.