Calibration of an X-band commercial radar and reflectivity measurements in suburban areas

Abstract

Calibrating a radar system, i.e., establishing a precise relationship between the radar observable (the power level of the received signal) and the radar cross section (RCS, the equivalent echoing area) of the object, or surface, of interest is not a trivial task. Concerning radar observables, in this work, we are mostly interested in land clutter (bare soil and soil with vegetation of different types) and manmade objects such as buildings, lampposts, and tankers. Our aim is to calibrate a simple, lightweight X-band radar to create a map of the land clutter of a suburban and rural area, using the one around Tor Vergata University, Rome. In the frame of the vast literature on measurement and modeling of land clutter (see, for instance, the classical works in [1]–[3]), this article aims to contribute a practical methodology based on a movable, lightweight, small, and cheap marine radar and its calibration. Live results are also analyzed; they are related to RCS measurements in a typical suburban area, i.e., the one around Tor Vergata University, within the border of the Roma town district and close to the town districts of Frascati and Monteporzio Catone in the Castelli Romani area. University buildings, residential buildings, streets, highways, car-parking areas with different coatings, large and medium lampposts, bare soil, and soil with grass and trees, all in a radius of a few kilometers, make this area interesting as far as land clutter characterization is concerned. The main aims of such clutter characterization are the design and the optimal siting of X-band surveillance radars for various purposes, including the surveillance of airports (surface movements radar and apron control) and the surveillance of urban and suburban areas for detection of unauthorized drones. In all of these radar applications, a map of the clutter levels for each radar position is a useful tool.