Angular accuracy improvement in digital array radar with experimental analysis

Abstract

In this paper, we propose a digital array radar (DAR) capable of detecting multiple targets accurately using multiple simultaneous digital beam forming and phase comparison monopulse. The system forms 3 simultaneous beams with azimuth coverage of 68 degrees. After beam forming, 3 parallel chains of radar signal processing are applied to the input signals. The processing chains include Range FFT, Moving Target Indication (MTI), Moving Target Detection (MTD) and Constant False Alarm Rate (CFAR) algorithms. Detection report produces Target's range, azimuth and velocity information. However due to wide beam widths, the improvement in angular accuracy is required. After initial target detections, the targets are queued for digital monopulse processing for improving angular accuracy. After performing monopulse processing, the targets are displayed on a PPI. This system can detect multiple targets simultaneously in 68° field of view with angular accuracy of 3.09° (1/12 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">th</sup> of the beam width). The proposed system is realized using an analog devices' TinyRad kit.