A Master of Science thesis in Electrical Engineering by Mansour Taghadosi entitled, "Miniaturized Low-Cost High-Performance Digital Radar," submitted in May 2015. Thesis advisors are Dr. Lutfi Albasha and Dr. Hasan Mir. Soft and hard copy available.
Digital radars offer added advantages and functionality such as higher stability and precision compared to conventional radar systems. By utilizing multiple receiver channels, digital array radars (DARs) are able to perform several functions such as tracking a specific target in space, while rejecting jammers from a certain angular location (known as spatial filtering). This is of interest in high clutter environments such as coastlines. This study aims to miniaturize a cutting-edge digital radar testbed implemented using discrete microwave components, developed earlier at the American University of Sharjah. The main objectives of the thesis are to achieve a level of practical portability for the system without compromising the overall performance and to maintain a low cost budget. Furthermore, this study presents several characteristics of digital radars and discusses the limitations and constraints faced during their design and implementation phases. The novel architecture design and implementation process of the miniaturized low-cost and high-performance S-band digital radar is presented. The proposed system is simulated through multiple software platforms including advanced design system (ADS) and advancing the wireless revolution's (AWR) visual system simulator (VSS). This report details the design and full-wave EM simulation of different types of filters specifically designed to be implemented in the radar testbed. It also explains the impedance matching procedure followed in order to minimize power losses. The overall system is first designed for the standard low-cost printed circuit board (PCB) technology, then simulated using the aforementioned software, and finally fabricated. The implemented radar testbed utilizes the stretch processing technique in order to achieve a high dynamic range over a wide signal bandwidth. The experimental measurements of the fabricated radar testbed verify a high in-band dynamic range of 75 dB across an instantaneous bandwidth of 600 MHz, corresponding to 0.25 meters of range resolution. The achieved high dynamic range is unique and has not yet been explored for the miniaturized scale of digital radar testbeds.