Performance Analysis of GEO-LEO SAR ATI

Total surface current velocity vector (TSCV) plays an important role for understanding the dynamic and static sea surface process. Synthetic Aperture Radar Along Track Interferometry (SAR ATI) has its special advantages for high accuracy and large area measurement, thus it becomes a mainstream remote sensing measurement method. The successful launch of GEO SAR gives an opportunity for long time ocean current monitoring and wide area measuring, however, due to the long integration time of GEO SAR, it usually can't satisfy the limitation of de-correlation time of sea surface. To deal with this problem, a heterogeneous distributed GEO-LEO SAR system has been proposed. To analyze the ATI performance of this system, a new ATI phase model has been derived, velocity resolution, the unambiguous velocity as well as the accuracy are all considered and analyzed by full link ATI simulation. As a result, it can be concluded that GEO-LEO SAR ATI system has the potential to achieve high precision current measurement with 100-meter resolution, and the performance is closely related to the configuration parameters, besides, the influencing factors of accuracy are also showed in the simulation results.