Accidental radio jamming suppression in passive radar

Bistatic passive radar based on opportunity illuminators such as FM radio, is a hotspot in the domain of radar. The direct/multi-path signals cancellation techniques(DSC) have been discussed by many scholars. These considered algorithms adopt a single-stage adaptive filter processor frame, have sufficient performance in the cancellation of the direct/multi-path interference signals from the selected transmitter. In practice, because of the complicated atmospheric propagation influence (as maritime evaporation ducts), or the active radio jamming, the single-stage DSC would be invalid. In this paper, we propose a two-stage canceller to suppress the direct interferences and the jamming of the unknown radio at the same frequency. Field experiments and simulations validate our proposition. After direct/multi-path signals being cancelled in the first stage, the second stage of the canceller can improve the jamming suppression above 20 dB.