Optimum reference signal reconstruction for DVB-T based passive radars

The present work investigates the optimum reconstruction of the reference signal for passive coherent location (PCL) radars exploiting Digital Video Broadcasting-Terrestrial (DVB-T) signals. Reference signal reconstruction is widely used to improve the signal-to-noise ratio (SNR) in the reference signal for DVB-T based PCL radars. Reference signal reconstruction is limited since for low SNR values, the signal demodulation is not sufficiently accurate which leads to a mismatch between the reconstructed signal and the transmitted one. In this work, we propose an optimum reconstruction strategy that includes an optimum estimation of the detected quadrature amplitude modulation (QAM) symbols, specific for radar applications. To verify the proposed detection strategy, we calculated analytic models for the optimum filter and the detection statistics. The analytic models are validated through Monte-Carlo simulations. The results show that the proposed method outperforms the conventional reference signal reconstruction scheme in terms of detection probability.