Optimal Fusion-Based Target Detection With Multichannel ATI SAR

In this article, an optimal fusion-based target detector with multichannel along-track interferometry (ATI) synthetic aperture radar (SAR) is investigated for ground moving target indication (GMTI) in a heterogeneous background. In the proposed method, a group of multibaseline ATI-phase tests for fully exploiting the spatial degrees of freedom (DoF) and the adaptive matched filter (AMF) test are first exploited for local target detection. Then, the global detection is designed based on Chair and Varshney’s optimal fusion rule. The optimal local detection thresholds are determined by designing the global optimization in terms of the optimal fusion rule. Therefore, the maximum target detection performance under the constant probability of false alarm (Pfa) can be achieved. To facilitate the implementation, a low-complexity solution to the global optimization and a cognitive detection framework for the proposed detector without the prior target knowledge is developed. Simulation and experimental results of the receiver operator characteristic (ROC) demonstrate its significant advantages in detecting dim targets that have a low signal-to-clutter-plus-noise ratio (SCNR) and small radial velocity in heterogeneous clutter backgrounds.