Deghosting in passive air surveillance systems

Digital Audio/Video Broadcasting (DAB/DVB-T) is already available in a large area of Europe. The advantage of using these signals for passive air surveillance is the disposability of a large range of illuminators sending an easily decodeable digital broadcast signal. In the considered multi-static scenario, one observer provides bistatic Time Difference of Arrival (TDoA), Doppler and (with limited quality) also azimuth measurements. The main task of target tracking is to handle ghosts that arise due to problems of association between illuminators, targets and measurements. To prevent enumeration and maintaining of all association possibilities, a decision criteria needs to be found to discriminate ghosts quickly and efficiently. In this paper we try to give a general understanding of the characteristics of ghosts; we derive two different Deghosting criteria and compare their performance with respect to Monte-Carlo simulations.