Monopulse range-doppler FMCW radar signal processing for spatial localization of moving targets

Abstract

Spatial localization of moving targets using a Monopulse/FMCW Radar system signal processing scheme is presented in this work. During many years radar sensor application has been used to measure different target parameters and consecutively leading to spatial localization systems, so that has been an active research area in many important fields, from military to civilian applications. Spatial localization of moving targets consists of sensing and estimating the coordinates where the target is located and its speed and direction. The immediate goal of this work is to measure the distance, velocity and angle parameters of each target detected basing on a set of FMCW-Radar measurements and a monopulse phase comparison method, therefore obtaining spatial localization of moving targets scheme, taking into account that the localization area should be limited depending on the radar sensor used and its features. Like this, there is a need to achieve the localization with the best possible measurement accuracy and in any situation, and this can be solved with a simple and cheap technology as mm-wave FMCW radars, that are remarkable because work-well in harsh environments and have a very high resolution for ranging, velocity and imaging method, a distance measurement resolution of 2 cm can be easily achieved over 30-40 meters working at 24GHz. Moreover the method presented is especially suited to detect very weak moving targets. Many applications where FMCW radar and Monopulse radar are playing an important role are: disaster situations of buried alive people, level-measuring systems, dimension verification systems, wall penetrating applications, air traffic control, terrain avoidance systems, etc [1]. It is clear that all cited applications could become more attractive and useful by using a suitable localization method as presented in this work. Besides the theoretical development and explanation of the proposed method, exemplary situations and measurements results will be presented to illustrate the capability of the algorithm. Real measurements will be made using a Monopulse/FSK/FMCW Radar with one transmitter / two receiver antennas at K-band. The signal evaluation was applied on a field programmable gate array (FPGA) to facilitate real time processing.