Direction of arrival estimation for multi-frequency FM-based Passive Bistatic Radar

In this paper we introduce a multi-frequency approach for improving target Direction of Arrival (DoA) estimation in FM radio based Passive Bistatic Radar (PBR). The joint exploitation of the waveforms of opportunity received on multiple FM radio channels in the 88-108 MHz band is shown to yield better performance in terms of detection capability and DoA estimation accuracy, since it is robust with respect to both the broadcasted radio program content and to the propagation channel conditions. To demonstrate the effectiveness of the proposed approach an experimental FM-based PBR prototype has been developed and fielded at dthe DIET Dept. of the University of Rome "La Sapienza". The acquisition campaigns that have been carried out are described together with the collected data analysis and processing. Finally, the results obtained over the collected data set for the single FM channels and after the proposed multi-frequency DoA estimation technique are reported and compared with live air traffic control registrations.