PC-YOLO: Moving Target Detection in Video SAR via YOLO on Principal Components

Video synthetic aperture radar could provide more valuable information than static images. However, it suffers from several difficulties, such as strong clutter, low signal-to-noise ratio, and variable target scale. The task of moving target detection is therefore difficult to achieve. To solve these problems, this paper proposes a model and data co-driven learning method called look once on principal components (PC-YOLO). Unlike preceding works, we regarded the imaging scenario as a combination of low-rank and sparse scenes in theory. The former models the global, slowly varying background information, while the latter expresses the localized anomalies. These were then separated using the principal component decomposition technique to reduce the clutter while simultaneously enhancing the moving targets. The resulting principal components were then handled by an improved version of the look once framework. Since the moving targets featured various scales and weak scattering coefficients, the hierarchical attention mechanism and the cross-scale feature fusion strategy were introduced to further improve the detection performance. Finally, multiple rounds of experiments were performed to verify the proposed method, with the results proving that it could achieve more than 30% improvement in mAP compared to classical methods.