A UB-ETDA-Based Spaceborne SAR Parameter Design Method for Enhanced Extended Target Detection Performance

For extended target detection, most existing spaceborne synthetic aperture radar (SAR) parameter design methods primarily focus on ensuring normal system operation, with limited consideration of the impact of SAR parameters on extended target detection performance. To enhance the extended target detection performance of spaceborne SAR from a parameter design perspective, a novel parameter design method based on an upper bound on extended target detection accuracy (UB-ETDA) is proposed, which comprehensively accounts for key factors affecting extended target detection performance, including aspect-dependent scattering characteristics of the extended target and spatial correlation properties of clutter. By employing UB-ETDA as a new performance metric to guide spaceborne SAR parameter design, the extended target detection performance of the system can be effectively improved. First, a statistical signal model for spaceborne SAR extended target detection is developed, systematically characterizing the stochastic properties of the extended target, background clutter, and noise components in SAR images. Then, the expression of UB-ETDA for SAR system is rigorously derived, along with a stable and statistically efficient numerical computation method. Finally, with UB-ETDA as the primary performance metric and existing performance metrics as constraints, a spaceborne SAR parameter design method is proposed for improving extended target detection performance. Simulation results validate the effectiveness of the proposed method.