Impact of supervised reciprocal filter on clutter cancellation in OFDM radar

This paper investigates the impact of a supervised reciprocal filter (RF)-based range compression on clutter cancellation in orthogonal frequency-division multiplexing (OFDM) radar. Previous studies have shown that, whilst it offers improved performance in terms of range-Doppler response control, the conventional RF suffers from a significant signal-to-noise ratio loss when applied to OFDM signals, if non-OFDM batching strategy is adopted. Therefore, a series of supervision techniques for the RF have been proposed aiming to recover this loss while preserving the RF’s advantages in terms of range-Doppler sidelobes floor level, thereby allowing flexible fragmentation strategies. Nonetheless, the impact of these supervision techniques on subsequent signal processing stages, particularly clutter cancellation, needs further investigation. In fact, since any supervision strategy is inherently signal dependent, it might impact the invariant characteristic of the RF response that in turn allows low-complexity cancellation schemes to be effectively exploited. By analyzing the simulated scenario of a Digital Video Broadcasting - Terrestrial based passive radar, we investigate the advantages and limitations of different supervised RF strategies in terms of clutter suppression and target detection. The comparative analysis provides further insights into the performance of the proposed approaches and gives hints to their practical application.