Experimental Results for Mobile OFDM Radar Using NULA and Supervised Reciprocal Filter Based DPCA

In this paper, we present an experimental validation of the recently proposed Thresholded DPCA Reciprocal Filter (T-DPCA-RF) technique for moving target indication (MTI) in radar systems using OFDM waveforms and a non-uniform linear array (NULA). The main challenge in mobile OFDM radar arises from the compound effects of platform motion and data-dependent characteristics of OFDM waveforms. The T-DPCA-RF processing scheme addresses this challenge by allowing to process the received signal in batches of arbitrary length, moving beyond the previous constraint of operating over signal batches corresponding to individual OFDM symbols. In addition, being based on a reciprocal filter strategy for range compression, it mitigates the temporal variability due to the information content of the adopted waveform. This flexibility allows to achieve the so-called “perfect DPCA condition”, essential for effective clutter suppression, regardless of the platform velocity or the antenna spacings. As a result, employing multi-antenna arrays on receive, possibly with non-uniform spacings becomes practically feasible, thus enhancing detection of slow-moving targets and increasing robustness to blind velocity effects. The experimental results confirm the practical effectiveness of the T-DPCA-RF technique and demonstrate the benefits of using NULA for enhanced MTI performance.