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Passive radar for terminal area surveillance: Performance feasibility study

Passive radars exploiting ambient illuminators of opportunity are developing into mature sensors that might fill roles currently requiring active primary radars. This paper considers the efficacy of on-field passive radars to provide low-altitude terminal-area surveillance at each of 4,661 unique airports within the United States, a role difficult to fill using a smaller number of more-expensive active radars. Simulations included terrain and 6,619 real-world television stations, and results indicate that modest passive radars might provide short-range accuracies similar to the ASR-11 for most of the examined approaches. Furthermore, a low-cost beacon is presented that enables in-situ signal integrity monitoring, and experimental results demonstrate short range detection of both aircraft and the beacon.