AAV MiniSAR Long-Integration-Time Imaging by Modeling Spatial Variance as Sinusoidal Series

Factors such as wind and rotors make the autonomous aerial vehicle (AAV) move away from the ideal flight trajectory, introducing complex relative movement between synthetic aperture radar (SAR) and target during long integration time, resulting in the two-dimensional space-variant defocusing characteristics of imaging. In order to form well-focused images, a motion error model based on sinusoidal series is proposed. Subsequently, through the extraction of motion error from a limited number of prominent scatters in the scene, the coefficients of the motion error model are determined, enabling precise compensation for the complex spatial variance. Validation results based on the simulated and real data of AAV SAR show that the proposed algorithm has well-focusing effect.