UAV Detection and Localization Using Passive DVB-T Radar MFN and SFN

For now many years [1] [2], passive radars using transmitters of opportunity have been studied and their capabilities and limitations for detecting and localizing “classical” air targets are now quite well known. The most famous transmitters of opportunity considered are FM, DAB (Digital Audio Broadcasting), DVB (Digital Video Broadcasting) [3] and more recently, some studies are dealing with WiFi transmitters[4]. However, despite the advantages of such passive radar components, such systems are not in use under operational forces. Our purpose is to illustrate a new promising interest of the DVB component by taking advantages of the DVB-T low altitude detection capabilities. As such DVB-T illuminators offer interesting range resolution at short ranges and very low to low altitude, DVB-T component has to be studied and evaluated for detecting and localizing UAVs in order to protect critical and/or isolated infrastructure. At the end of 2014, many illegal drones flights were noticed among several European and none European countries showing a lack in the low altitude coverage for small slowly moving objects such as UAVs. Due to the passive DVB-T system capabilities such a survey objective could typically be addressed by such passive radar components. This paper will illustrate and analyse several UAV detections at up to 3 kilometres in different bistatic and multistatic configurations. 1.0 INTRODUCTION For a couple of years several illegal drone flights have been noticed in several countries leading to an analysis of the different surveillance systems able to cope with such malicious flights. By considering a radar survey component, such a system has to ensure :  Low and very low altitude coverage  Detection of small and very small targets (typically up to a few kilogrammes by taking into account UAV such as DJI or similar)  Detection of slow moving target with high manoeuvring capabilities  Continuous detection from a few kilometres up to quite zero (so short range radar with no blind STO-MP-SET-231 18 1 PUBLIC RELEASE PUBLIC RELEASE UAV Detection and Localization Using Passive DVB-T Radar MFN and SFN zone).  Detection 24h/24h.  Preliminary discrimination capabilities between UAV and other mobile targets. Such requirements may be fulfilled, sometimes after some adaptations, by :  Battlefield radars  Radars for monitoring the birds migration  Passive DVB-T radars. Our objective is to illustrate and demonstrate, by using several experimental results, the good behaviour of a passive DVB-T radar component for struggling against illegal UAV flights. The first chapter will briefly present the main characteristics of the DVB receiver used during the different experiments and will analyse and verify the potential interest of such a passive DVB-T component by analysing most of the different requirements mentioned above. The second chapter will illustrate the main different results obtained during the different experiments :  modulation blades that are detectable by using such DVB passive radar.  detection capabilities under several bi(multi)static configurations including a UAV detection in a SFN (Single Frequency Network) mode.  location capabilities with such a system when using a single bistatic base. In summary, this paper will focus on the validation of the passive DVB capabilities against illegal UAV flights by presenting experimental results corresponding to different (four among the five evaluated) bistatic configurations. 2.0 DVB RECEIVER CHARACTERISTICS AND COMPONENT INTEREST 2.1 DVB receiver characteristics The DVB receiver used for all the results presented here is simply based on a  Eight antenna system  Each antenna is related to an analogue receiver channel  All the eight antenna channels are digitalized  And the processing is an off-line one This system is able to record only one DVB frequency bandwidth per record. UAV Detection and Localization Using Passive DVB-T Radar MFN and SFN 18 2 STO-MP-SET-231 PUBLIC RELEASE