A Tracking Method in FM Broadcast-based Passive Radar Systems

Abstract

Passive radars are popular because without the expensive, high-power-rated RF components, they are much cheaper than the active ones, nevertheless, they are much harder to detect from their electromagnetic emission. Passive radars produce so-called RV matrices in an intermediate signal processing step. Although accurate RV matrices are found in DVBT-based passive radars, the characteristics of the FM signals are not always suitable for this purpose. In those situations, further signal processing causes false alarms and unreliable plots, misleads the tracker, and consumes power for processing unnecessarily, which matters in portable setups. Passive radars also come with the advantage of a possible MIMO setup, when multiple signal sources (broadcast services for example) are reflected by multiple targets to the receiver unit. One common case is the stealth aircraft’s which form is designed to reflect the radar signal away from the active radar, but it could also reflect the signals of the available broadcast channels. Only one of these reflected signals could reveal the position of the target.