Small Unmanned Aerial Vehicles (UAVs) and drones are becoming an ever increasing threat for the aviation safety and the airport security. Consequently, the detection, localization and tracking of such targets have become key requirements for surveillance systems. However, significant challenges exist given the small size and high manoeuvrability of such targets.
In this project, the effectiveness of DVB-T based Passive Radar in detection and localization of drones is investigated aiming at monitoring airport terminal areas. For the purpose, an appropriate signal processing architecture is proposed and the effectiveness of the proposed solutions is validated on experimental datasets collected by a DVB-T based PR.
The potential of a DVB-T PR has been widely demonstrated in both air traffic control and maritime/coastal surveillance applications, [1]-[6]. With reference to the first application, the PR is able to detect and localize the typical aerial traffic up to very long range distance as well as small aircrafts (e.g. ultralights), [1]-[4]. For the maritime scenario, the sensor allows the detection, localization and imaging of vessels of different dimensions located both close to the coast and at long range distances, [2],[5]-[6]. In contrast, the passive radar detection of small UAVs represents a hot topic and few works are available in the literature. Particularly, the feasibility studies have been reported [7]-[9] suggesting the possibility to use this technology for drone detection.
The main challenging aspect to be pointed out is that, differently from aircrafts and vessels drones are often smaller than 1 square meter and mostly made of non-metallic materials. Additionally, they are characterized by high manoeuvrability and some of them fly at low velocity and low altitude. The complex motion, along with the low RCS, make the drone detection a complex task for any radar system. This means that the conventional approaches, usually employed in PR for detection, localization and tracking of aerial and naval targets, lacks the drone detection. Therefore, effective approaches, specifically tailored for this particular class of targets, need to be define and developed.
The main scope of this project is studying and developing proper methods to enable the detection of small and medium drones via a DVB-T based PR. For the purpose, a processing scheme tailored for drone detection will be proposed. Then, the effectiveness of the proposed solutions will be preliminary investigated using synthetic datasets.
Moreover, in order to validate the developed approaches in practical scenarios, dedicated acquisition campaigns will be carried out using DVB-T based passive sensor prototypes. Drones of different size flying with different trajectories will be considered. The employed targets will be all equipped with a GPS receiver that continuously record their position: this allows performing a comparison between the passive sensor results and the drone air truth. This will allow to verify the practical effectiveness of the proposed processing scheme and highlight its suitability for drone surveillance in an airport scenario.
[1] D. Poullin and M. Flecheux, "Passive 3D tracking of low altitude targets using DVB (SFN Broadcasters)," in IEEE Aerospace and Electronic Systems Magazine, vol. 27, no. 11, pp. 36-41, November 2012.
[2] T. Martelli, F. Colone, E. Tilli, and A. Di Lallo, "Multi-Frequency Target Detection Techniques for DVB-T Based Passive Radar Sensors," in Sensors 2016, Sept. 2016.
[3] F. Pignol, F. Colone and T. Martelli, "Lagrange-Polynomial-Interpolation-Based Keystone Transform for a Passive Radar," in IEEE Trans. on AES, vol. 54, no. 3, pp. 1151-1167, June 2018.
[4] F. Filippini, T. Martelli, F. Colone, R. Cardinali,"Exploiting long coherent integration times in DVB-T based passive radar systems," 2019 IEEE Radar Conference (RadarConf19), Boston, USA, April 2019.
[5] D.W O'Hagan., A. Capria, D.Petri, V.Kubica, M.Greco, F.Berizzi, A.G. Stove, "Passive Bistatic Radar (PBR) for harbour protection applications," IEEE Radar Conference 2012, Atlanta (GA), USA, May 2012.
[6] T. Martelli, F. Filippini, F. Pignol, F. Colone and R. Cardinali, "Computationally effective range migration compensation in PCL systems for maritime surveillance," 2018 IEEE Radar Conference (RadarConf18), Oklahoma City, OK, 2018, pp. 1406-1411.
[7] Y. Liu, X. Wan, H. Tang, J. Yi, Y. Cheng and X. Zhang, "Digital television based passive bistatic radar system for drone detection," IEEE Radar Conference 2017, Seattle, WA, 2017, pp. 1493-1497.
[8] D. Poullin, "Countering illegal UAV flights: passive DVB radar potentiality," International Radar Symposium 2018, Bonn, pp. 1-10.
[9] M. P. Jarabo-Amores et al., "Drone detection feasibility with passive radars," European Radar Conference 2018, Madrid, Spain, pp. 313-316.