Dr. Diego Cristallini is Head of the Passive Radar Group at Fraunhofer FHR. He graduated cum laude in Telecommunication Engineering in May 2006 and received the Ph.D. degree in Radar Remote Sensing in April 2010 both from the University of Rome “La Sapienza”. From December 2009 to February 2015 he has been with the Array-based Radar Imaging Department of the Fraunhofer Institute for High Frequency Physics and Radar Techniques FHR in Wachtberg, Germany. Since March 2015, Diego is leading the Team on Passive Covert Radar in the Passive Radar and Anti-Jamming Techniques Department of Fraunhofer FHR, Germany. From March to June 2020, he has been visiting scientist at Defence Science and Technology (DST) Group in Edinburgh, South Australia. Dr. Cristallini serves as voluntary Reviewer for a number of international technical journals, and he is active in the scientific community serving as TPC for several international conferences related to radar. He is also a regular lecturer at the Fraunhofer International Summer School on Radar and SAR. Dr. Cristallini is co-chair of the NATO-SET 242 group on “PCL on moving platforms” and he has been lecturing for the NATO LS-243 “Passive Radar Technology”. Dr. Cristallini received the Best Paper Award at EUSAR 2014, co-authored the Best Poster Award at EUSAR 2018, and

Tutorial description

Passive radar has now become an established technology. Among current active field of research it is worth mentioning the capability to perform imaging as well as the capability of detection of small objects such as drones. Satellite Illuminators of Opportunity (IOs) such as Digital Video Broadcast – Satellite (DVB-S) as well as the exploitation of emerging broadband communication satellite constellations (e.g. Starlink or OneWeb) offer interesting characteristics to perform these two tasks. In fact, they offer relatively wide signal bandwidths for passive radars (up to 2 GHz), they operate at high carrier frequencies (namely in Ku-Band), and these so-called megaconstellations with global and continuous coverage are planned to be composed of hundreds or thousands of satellites deployed at low Earth orbits (LEO), thus offering continuous and synoptic illumination on wide and also remote areas. In particular, while the wide signal bandwidth enables high range resolutions, the high operating frequency significantly increases the system sensibility against Doppler (and micro-Doppler) modulations with respect to other conventional passive radar IOs at lower frequencies. Both these aspects offer extremely appealing characteristics for detection and imaging.

Finally, preliminary experimental measurements will be presented. All of these analyses will provide an overview of the great potential capabilities achievable by using these novel satellite constellations as illuminators of opportunity, trying also to promote further research and developments in this field that will open up new and advanced passive radar applications.