Radar Cross-Section Analysis of In-Flight UAVs in X- and L-Band

This paper presents a comparative first-order statistical analysis of the radar cross-section (RCS) of in-flight unmanned aerial vehicles (UAVs) in the X- and L-bands. The study is based on measurements collected with a frequencymodulated continuous-wave (FMCW) radar in a rural area during the simultaneous flight of a commercial and a professionalgrade drone. The goal is to assess whether the statistical model describing the RCS fluctuations of these different consumergrade drones is influenced by factors such as drone type and the operating band. To this end, after describing the measurement setup along with the specifications of the two drones, a procedure for estimating the RCS from the collected data is provided. Then, the empirical cumulative distribution function (ECDF) of the estimated RCS data for each drone and across each frequency band is used to analyze the underlying RCS fluctuations. Regardless of the frequency band, the results highlight that the different UAVs conform to distinct RCS fluctuation models. Furthermore, these models vary between the X - and L-bands for each drone. These variations in the fluctuation models reflect both the different structural characteristics of the UAVs and the frequency dependence of the RCS, as the scatterers that compose the drone may respond differently depending on the frequency.