Detection of Moving Targets by Passive Radar Using FM Signals on Moving Platforms

Abstract

In this study, using FM radio signals for transmitters of opportunity, detection of moving targets by passive radar on moving platforms is investigated. Ground reflectivity is modelled as discrete patch approximation with uniform distribution in phase and Rayleigh distribution in amplitude. The target echo is modelled as Doppler shifted and delayed form of the transmit signal based on the target's angular position, range, and velocity. The clutter echoes, received by surveillance antennas, are also modelled by the superposition of Doppler shifted and delayed form of the transmit signal. Displaced Phase Center Array (DPCA) method is used for clutter rejection and moving target detection. Both matched filter and reciprocal filter are used in the pulse compression stage. The performance of the proposed method is evaluated by using an improvement factor (IF). DPCA with reciprocal filter outperforms DPCA with matched filter with the improvement value of 5,1 dB due to the reciprocal filter producing timeinvariant impulse responses.